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Sample records for cadherin-11 controls otolith

  1. Limb neurovascular control during altered otolithic input in humans

    Science.gov (United States)

    Monahan, Kevin D.; Ray, Chester A.

    2002-01-01

    Head-down rotation (HDR), which activates the vestibulosympathetic reflex, increases leg muscle sympathetic nerve activity (MSNA) and produces calf vasoconstriction with no change in either cardiac output or arterial blood pressure. Based on animal studies, it was hypothesized that differential control of arm and leg MSNA explains why HDR does not alter arterial blood pressure. Fifteen healthy subjects were studied. Heart rate, arterial blood pressure, forearm and calf blood flow, and leg MSNA responses were measured during HDR in these subjects. Simultaneous recordings of arm and leg MSNA were obtained from five of the subjects. Forearm and calf blood flow, vascular conductances, and vascular resistances were similar before HDR, as were arm and leg MSNA. HDR elicited similar significant increases in leg (Delta 6 +/- 1 bursts min(-1); 59 +/- 16 % from baseline) and arm MSNA (Delta 5 +/- 1 bursts min(-1); 80 +/- 28 % from baseline). HDR significantly decreased calf (-19 +/- 2 %) and forearm vascular conductance (-12 +/- 2 %) and significantly increased calf (25 +/- 4 %) and forearm vascular resistance (15 +/- 2 %), with 60 % greater vasoconstriction in the calf than in the forearm. Arterial blood pressure and heart rate were not altered by HDR. These results indicate that there is no differential control of MSNA in the arm and leg during altered feedback from the otolith organs in humans, but that greater vasoconstriction occurs in the calf than in the forearm. These findings indicate that vasodilatation occurs in other vascular bed(s) to account for the lack of increase in arterial blood pressure during HDR.

  2. Molecular analysis of E-cadherin and cadherin-11 in Wilms' tumours.

    Science.gov (United States)

    Schulz, S; Becker, K F; Braungart, E; Reichmuth, C; Klamt, B; Becker, I; Atkinson, M; Gessler, M; Höfler, H

    2000-06-01

    Different studies of Wilms' tumours have demonstrated a loss of heterozygosity (LOH) of chromosome 16q ranging from 17 to 25%. In order to search for a potential tumour suppressor gene on 16q, we chose the calcium-dependent cell adhesion molecules E-cadherin and cadherin-11 as candidate genes, which are both located on the long arm of chromosome 16. E-cadherin is known to be expressed in epithelial structures, whereas cadherin-11 is supposed to be expressed in mesenchymal structures and developing epithelium, including renal tubules. For the present study, fresh frozen tissue from 30 Wilms' tumours and corresponding non-tumour tissues were analysed. Single nucleotide polymorphisms of the E-cadherin and cadherin-11 genes were chosen and analysed for allelic inactivation by polymerase chain reaction (PCR) amplification and sequence analysis. Loss of expression of one E-cadherin allele was seen in 10% (2/20) of the informative cases. Two out of 11 informative cases (18%) showed loss of expression of one cadherin-11 allele. No length alterations of either the E-cadherin or the cadherin-11 messenger RNAs were identified using reverse transcription PCR and agarose gel electrophoresis in tumour tissue. Sequencing of the entire E-cadherin coding region in seven cases showed the wild-type sequence. These data imply that E-cadherin and cadherin-11 are not likely to play typical tumour suppressor roles in Wilms' tumour. Interestingly, the E-cadherin immunohistochemistry showed a deviation from the normal reaction pattern in 50% of the cases, with 27% (8/30) showing an apical or cytoplasmic reaction and 23% (7/30) being completely negative. Northern blot analysis revealed that the overall expression of cadherin-11 is much stronger than that of E-cadherin. In several cases, the expression levels of the two genes were inversely correlated, suggesting the existence of a regulatory mechanism. Analysis of differential expression of the various cadherins and their subsequent signal

  3. ZAG-Otolith: Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control during Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, S. J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, centrifugation, and measure the time course of postflight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved with vibrotactile feedback of orientation.

  4. ZAG-Otolith: Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control during Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, S. J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, <20 cm radius), the effects of stimulus frequency (0.15 - 0.6 Hz) are examined on eye movements and motion perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. PRELIMINARY RESULTS. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. DISCUSSION. One result of this study will be to characterize the variability (gain, asymmetry) in both otolithocular responses and motion perception during variable radius centrifugation, and measure the time course of postflight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual

  5. ZAG-Otolith: Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control during Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, S. J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. PRELIMINARY RESULTS. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. DISCUSSION. One result of this study will be to characterize the variability (gain, asymmetry) in both otolithocular responses and motion perception during variable radius centrifugation, and measure the time course of postflight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved with vibrotactile feedback of orientation.

  6. Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control During Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, Scott J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, less than 20 cm radius), the effects of stimulus frequency (0.15 - 0.6 Hz) are examined on eye movements and motion perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. One result of this study will be to characterize the variability (gain, asymmetry) in both otolith-ocular responses and motion perception during variable radius centrifugation, and measure the time course of post-flight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved

  7. AP-1 Transcription Factors c-FOS and c-JUN Mediate GnRH-Induced Cadherin-11 Expression and Trophoblast Cell Invasion.

    Science.gov (United States)

    Peng, Bo; Zhu, Hua; Ma, Liyang; Wang, Yan-Ling; Klausen, Christian; Leung, Peter C K

    2015-06-01

    GnRH is expressed in first-trimester human placenta and increases cell invasion in extravillous cytotrophoblasts (EVTs). Invasive phenotypes have been reported to be regulated by transcription factor activator protein 1 (AP-1) and mesenchymal cadherin-11. The aim of our study was to investigate the roles of AP-1 components (c-FOS/c-JUN) and cadherin-11 in GnRH-induced cell invasion in human EVT cells. Phosphorylated c-FOS and phosphorylated c-JUN were detected in the cell column regions of human first-trimester placental villi by immunohistochemistry. GnRH treatment increased c-FOS, c-JUN, and cadherin-11 mRNA and protein levels in immortalized EVT (HTR-8/SVneo) cells. Moreover, GnRH treatment induced c-FOS and c-JUN protein phosphorylation and nuclear accumulation. Pretreatment with antide, a GnRH antagonist, attenuated GnRH-induced cadherin-11 expression. Importantly, basal and GnRH-induced cadherin-11 expression and cell invasion were reduced by small interfering RNA-mediated knockdown of c-FOS, c-JUN, and cadherin-11 in HTR-8/SVneo cells. Our results suggest that GnRH induces the expression and phosphorylation of the AP-1 transcription factors c-FOS and c-JUN in trophoblast cells, which contributes to GnRH-induced elevation of cadherin-11 expression and cell invasion. PMID:25794160

  8. Cadherin-11 contributes to pulmonary fibrosis: potential role in TGF-β production and epithelial to mesenchymal transition

    OpenAIRE

    Daniel J. Schneider; Wu, Minghua; Thuy T Le; Cho, Seo-Hee; Brenner, Michael B.; Blackburn, Michael R.; Agarwal, Sandeep K

    2012-01-01

    Pulmonary fibrosis, characterized by excess deposition of extracellular matrix by myofibroblasts, is a serious component of chronic lung diseases. Cadherin-11 (CDH11) is increased in wound healing and fibrotic skin. We hypothesized that CDH11 is increased in pulmonary fibrosis and contributes its development. CDH11 expression was assessed in lung tissue from idiopathic pulmonary fibrosis patients. The role of CDH11 in lung fibrosis was determined using the bleomycin model of pulmonary fibrosi...

  9. Functional loss of E-cadherin and cadherin-11 alleles on chromosome 16q22 in colonic cancer.

    Science.gov (United States)

    Braungart, E; Schumacher, C; Hartmann, E; Nekarda, H; Becker, K F; Höfler, H; Atkinson, M J

    1999-04-01

    Proteins of the cadherin family regulate cellular adhesion and motility and are believed to act as tumour suppressors. Previous studies have identified frequent mutation and allelic inactivation of the E-cadherin (cadherin-1) locus in diffuse gastric cancer. At least two other cadherin genes, P-cadherin (cadherin-3) and OB-cadherin (cadherin-11), have been mapped close to the E-cadherin gene on chromosome 16q22. As this region of the genome is frequently deleted in malignancy, multiple cadherin loci may be affected by losses of chromosome 16q22. The expression of mRNA transcripts from polymorphic alleles of the E-cadherin and cadherin-11 genes was examined in 30 cases of colonic, gastric, and renal carcinoma. In gastric cancer, loss of expression of one allele was restricted to the E-cadherin locus, whilst in renal carcinoma neither locus was affected. In colonic cancers, loss of expression of one E-cadherin allele was detected in 5 of 22 cases, whilst loss of a cadherin-11 allele was seen in 5 of 23 cases. This functional loss of cadherin gene expression may be due to gene deletion, inactivation or recombination. As no evidence of cadherin gene mutation was observed in the remaining transcripts, we can conclude that these two genes are only indirectly involved in the pathogenesis of colorectal cancer. PMID:10398117

  10. Restricted fish feeding reduces cod otolith opacity

    DEFF Research Database (Denmark)

    Høie, H.; Folkvord, A.; Mosegaard, Henrik; Li, L.; Worsøe Clausen, Lotte; Norberg, B.; Geffen, A.J.

    2008-01-01

    the otolith sections. The otolith carbonate deposited during the experimental period was generally opaque compared to the more translucent otolith material deposited prior to and after the experimental period, when the fish were kept in a pond and in sea-cages at higher temperatures. Large variations...... in otolith opacity were found between individual fish both within groups and between groups. In two of the three groups significantly more translucent otolith material was deposited in response to reduced feeding. Our results show that variations in feeding and hence fish growth resulted in variation...... in otolith opacity, but the effect was minor compared to that of variations in ambient temperature. The combined influence of these effects, which both act on fish metabolism, are most likely controlling the seasonal opacity changes observed in wild fish. Our results help explain the variations seen...

  11. The intracellular domain of cadherin-11 is not required for the induction of cell aggregation, adhesion or gap-junction formation.

    Science.gov (United States)

    Braungart, E; Hartman, E; Bechler, K; Höfler, H; Atkinson, M J

    2001-01-01

    The cadherin family of cell adhesion molecules demonstrates calcium-dependent homophilic binding, leading to cellular recognition and adhesion. The adhesion mediated by the classical type I cadherins is strengthened through catenin-mediated coupling of the cytoplasmic domain to the cytoskeleton. This cytoskeletal interaction may not be essential for the adhesion promoted by all cadherins, several of which lack cytosolic catenin-binding sequences. Cadherin-11, a classical cadherin, possesses a cytoplasmic domain that interacts with catenins, but may also occur as a variant form expressing a truncated cytoplasmic domain. To study the role of the cytoplasmic sequence in cadherin-11 mediated adhesion we have constructed and expressed a truncated cadherin-11 protein lacking the cytoplasmic domain and unable to bind beta-catenin. Expression of the truncated cadherin-11 in MDA-MB-435S human mammary carcinoma cells reduced their motility and promoted calcium-dependent cell aggregation, frequent cell contacts, and functional gap-junctions. We conclude that the intracellular catenin-binding domain of cadherin-11, and by inference cytoskeletal interaction, is not required for the initiation and formation of cell adhesion. PMID:11775026

  12. Different pH-dependencies of the two synaptic adhesion molecules N-cadherin and cadherin-11 and the possible functional implication for long-term potentiation

    DEFF Research Database (Denmark)

    Baumgartner, Werner; Osmanagic, Armin; Gebhard, Marita;

    2013-01-01

    Ca(2+) -dependent adhesion molecules, cadherins, localised at synaptic sites are critically involved in long-term potentiation (LTP). N-cadherin is thought to promote LTP whereas cadherin-11 seems to counteract LTP. Since high synaptic activity is accompanied by local transient changes of the pH ...

  13. Ontogenic and ecological control of metamorphosis onset in a carapid fish, Carapus homei: experimental evidence from vertebra and otolith comparisons.

    Science.gov (United States)

    Parmentier, Eric; Lecchini, David; Lagardere, Francoise; Vandewalle, Pierre

    2004-08-01

    In Carapus homei, reef colonisation is associated with a penetration inside a sea cucumber followed by heavy transformations during which the length of the fish is reduced by 60%. By comparing vertebral axis to otolith ontogenetic changes, this study aimed (i) to specify the events linked to metamorphosis, and (ii) to establish to what extent these fish have the ability to delay it. Different larvae of C. homei were caught when settling on the reef and kept in different experimental conditions for at least 7 days and up to 21 days: darkness or natural light conditions, presence of sea cucumber or not, and food deprivation or not. Whatever the nutritional condition, a period of darkness seems sufficient to initiate metamorphosis. Twenty-one days in natural light conditions delayed metamorphosis, whereas the whole metamorphosis process is the fastest (15 days) for larvae living in sea cucumbers. Whether the metamorphosis was initiated or not, otoliths were modified with the formation of a transition zone, whose structure varied depending on the experimental conditions. At day 21, larvae maintained in darkness had an otolith transition zone with more increments (around 80), albeit wider than those (more or less 21) of individuals kept under natural lighting. These differences in otolith growth could indicate an increased incorporation rate of released metabolites by metamorphosing larvae. However, the presence of a transition zone in delayed-metamorphosis larvae suggests that these otolith changes record the endogenously-induced onset of metamorphosis, whereas body transformations seem to be modulated by the environmental conditions of settlement. PMID:15286941

  14. OTOLITHS AND THEIR APPLICATIONS IN FISHERY SCIENCE

    Directory of Open Access Journals (Sweden)

    Paola Rodriguez Mendoza

    2006-07-01

    Full Text Available Otoliths are structures located in the inner ear cavity of all teleost fish and serve as a balance organ and also aid in hearing. They have been used traditionally to obtain information about the taxon, age and size of fishes. This is very important because age, growth rate, and mortality rate are three of the most influential life history characteristics controlling the productivity of fish populations. Besides age and growth determination, otoliths have been the object of study in many different fields, such as fish biology (hearing and balance in fishes, larval fish ecology, species identification, fish stock identification and environmental reconstruction of the fish habitat. Thus, the purpose of this paper is to provide an overview of the traditional and current applications of the otoliths. Also, a short description of the traditional methods for age determination is included.

  15. Elevated CO2 enhances otolith growth in young fish.

    Science.gov (United States)

    Checkley, David M; Dickson, Andrew G; Takahashi, Motomitsu; Radich, J Adam; Eisenkolb, Nadine; Asch, Rebecca

    2009-06-26

    A large fraction of the carbon dioxide added to the atmosphere by human activity enters the sea, causing ocean acidification. We show that otoliths (aragonite ear bones) of young fish grown under high CO2 (low pH) conditions are larger than normal, contrary to expectation. We hypothesize that CO2 moves freely through the epithelium around the otoliths in young fish, accelerating otolith growth while the local pH is controlled. This is the converse of the effect commonly reported for structural biominerals. PMID:19556502

  16. Fish otolith biomineralization process: first investigations about organic matrix and growth of Triglidae (Scorpaeniformes otoliths

    Directory of Open Access Journals (Sweden)

    Stefano Montanini

    2015-11-01

    Full Text Available Otolith formation involves rhythmic variations in the deposition and size of organic matrix framework and carbonate crystals, resulting in the formation of macroscopic translucent and opaque rings and microscopic zonations (growth increments (Morales Nin, 2000. As in most biominerals, the otolith matrix forms only 2-3 % of its weight, but it is admitted that it has a considerable importance in the otolith crystallization processes of nucleation, growth, orientation and growth control. The goal of this study is to characterize the matrix protein composition in the otoliths of Triglidae (Scorpaeniformes as a first step to understand molecular mechanisms of otolith formation according to biology and ecology of the species. In particular 500 sagittal otoliths from six gurnard species were analysed: Chelidonichthys cuculus, C. lucerna, Eutrigla gurnardus, Lepidotrigla cavillone, L. dieuzeidei and Trigloporus lastoviza. Protein contents were estimated by Bradford method and the urea 8 M extracts were loaded into a polyacrylamide gel, separated by SDS page and detected by Silver staining (Sigma followed the protocol of Borelli et al. (2001 with some modifications regarding protein precipitation that was enhanced by using TCA, trichloroacetic acid, 100% w/v. The urea soluble fractions revealed a unique large band around 50-55 kDa. Another common clear band was visible at the top of the separating gel (proteins >300/350 kDa unable to enter into the pores of polyacrylamide gels (12%. The complexity of the protein mixtures was investigated by 2-D electrophoresis (Gel TGX 4-20%; proteins were separated on the basis of both isoelectric point (pI and molecular size. A common protein pattern of 50-75 kDa were found in all gurnards showing a similar composition of organic matter even if the 2-D maps of otolith samples showed specie-specific variation in acid protein fractions in all the pairwise comparison. This result confirmed that the amino acid composition

  17. Strontium and barium uptake in aragonitic otoliths of marine fish

    Science.gov (United States)

    Bath, Gretchen E.; Thorrold, Simon R.; Jones, Cynthia M.; Campana, Steven E.; McLaren, James W.; Lam, Joseph W. H.

    2000-05-01

    Minor and trace element analyses of fish otoliths (ear stones) may provide a high-resolution reconstruction of temperature histories and trace element compositions of aquatic systems where other environmental proxies are not available. However, before otoliths can be used to reconstruct water chemistry, it is essential to validate the assumption that trace metals in otoliths are deposited in proportion to dissolved concentrations in the ambient environment. We show, using a marine fish ( Leiostomus xanthurus) reared in the laboratory under controlled experimental conditions, that otolith Sr/Ca and Ba/Ca ratios are deposited in proportion to their respective ratios in ambient waters. Temperature significantly affected Sr incorporation but did not affect Ba incorporation in otoliths. Sr/Ca partition coefficients ( DSr) were 0.182 and 0.205 at 20°C and 25°C, respectively. The partition coefficients for Ba/Ca were 0.055 at 20°C and 0.062 at 25°C. A nonlinearity in the relationship between DBa and ambient Ba concentrations suggested that extrapolation beyond the Ba levels used in the experiment was not justified. On the basis of our results, it should be possible to reconstruct Sr/Ca and Ba/Ca levels in environments inhabited by fish based on otolith chemistry. Furthermore, Sr/Ca thermometry may also be possible using fish otoliths, but validation of the temperature dependence of Sr/Ca in otoliths will be required. We believe otoliths represent an excellent, and as yet underused, record of the physicochemical properties of both modern and ancient aquatic environments.

  18. A critical period for gravitational effects on otolith formation

    Science.gov (United States)

    Wiederhold, M.; Harrison, J.

    Gravity and linear acceleration are sensed in fish by the saccule, utricle (as in mammals) and lagena, each with a solid otolith. Previous experiments in which eggs or larvae of a marine mollusk ( plysia) or fish larvae were raised on aA centrifuge, demonstrated that the size of the otolith or statoconia (in Aplysia) were reduced, in a graded manner, as the gfield was increased, suggesting that some- control mechanism was acting to normalize the weight of the mass. Pre-mated adult female swordtail fish (Xiphophorus helleri) were flown in the CEBAS aquarium system on space shuttle missions STS 89 and STS-90 (Neurolab). Developing- larvae were removed from the adult ovaries after shuttle landing. Otolith sizes were compared between ground- and flight -reared larvae of similar sizes. For later-stage swordtail larvae, with spine lengths from 3 to 6 mm from STS-90 (16 days), the growth of the otolith with increasing spine length was significantly greater in the flight - reared fish for all three otoliths, from the saccule (saggita), utricle (lapillus) and lagena (astericus). However, juvenile fish, 1 cm long at launch, showed no significant difference in otolith size between flight - and ground-reared animals. In very early stage larvae from STS-89 (9 days), with spine length of 1.5 to 3.5 mm, the utricular and saccular otoliths were actually larger in the ground-reared larvae. Thus, it appears that late-stage fish embryos reared in space do produce larger-than - normal otoliths, apparently in an attempt to c mpensate for the reduced weight ofo the test mass in space. However, the results from very early-stage larvae and juvenile fish suggest that there is a fairly short critical period during which altered gravity can affect the size of the test mass. Recent studies on the development of the inner ear of the zebrafish (Danio raria) may explain the critical period for gravitational effects on otolith growth. By 16 hours after zebrafish fertilization (at 28.5 o

  19. Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight

    Science.gov (United States)

    Moore, Steven T.

    2004-01-01

    In contrast to previous studies, post-flight measures of both otolith-ocular function and orthostatic tolerance were unimpaired in four payload crewmembers exposed to artificial gravity generated by in-flight centrifugation during the Neurolab (STS-90) mission. The aim of the current proposal is to obtain control measures of otolith and orthostatic function following short duration missions, utilizing the centrifugation and autonomic testing techniques developed for the Neurolab mission, from astronauts who have not been exposed to in-flight centrifugation. This will enable a direct comparison with data obtained from the Neurolab crew. Deficits in otolith-ocular reflexes would support the hypothesis that intermittent exposure to in-flight centripetal acceleration is a countermeasure for otolith deconditioning. Furthermore, a correlation between post-flight otolith deconditioning and orthostatic intolerance would establish an otolithic basis for this condition.

  20. Swimming Behavior and Calcium Incorporation into inner Ear Otoliths of Fish after vestibular Nerve Transection

    Science.gov (United States)

    Edelmann, E.; Anken, R.; Rahmann, H.

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium-tracer alizarin- complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated: Like neonate swordtails, type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal and the otolithic calcium incorporation in controls of the same batch was symmetrical. In type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetrical. These results stongly suggest that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. Thus, it is assumed that the mechanisms regulating otolith growth and equlibibrium differ in the two types of cichlid fish. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

  1. Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection

    Science.gov (United States)

    Edelmann, E.; Anken, R. H.; Rahmann, H.

    2004-01-01

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

  2. Vestibular reflexes of otolith origin

    Science.gov (United States)

    Wilson, Victor J.

    1988-01-01

    The vestibular system and its role in the maintenance of posture and in motion sickness is investigated using cats as experimental subjects. The assumption is that better understanding of the physiology of vestibular pathways is not only of intrinsic value, but will help to explain and eventually alleviate the disturbances caused by vestibular malfunction, or by exposure to an unusual environment such as space. The first project deals with the influence on the spinal cord of stimulation of the vestibular labyrinth, particularly the otoliths. A second was concerned with the properties and neural basis of the tonic neck reflex. These two projects are related, because vestibulospinal and tonic neck reflexes interact in the maintenance of normal posture. The third project began with an interest in mechanisms of motion sickness, and eventually shifted to a study of central control of respiratory muscles involved in vomiting.

  3. Three dimensional imaging of otoliths

    International Nuclear Information System (INIS)

    Otoliths are small structures in fish ears made of calcium carbonate which carry a record of the environment in which the fish live. Traditionally, in order to study their microchemistry by a scanning technique such as PIXE the otoliths have been either ground down by hand or thin sectioned to expose the otolith core. However this technique is subject to human error in judging the core position. In this study we have scanned successive layers of otoliths 50 and 100 μm apart by removing the otolith material in a lapping machine which can be set to a few μm precision. In one study by comparing data from otoliths from the two ears of a freshwater species we found that polishing by hand could miss the core and thus give misleading results as to the life cycle of the fish. In another example we showed detail in a marine species which could be used to build a three dimensional picture of the Sr distribution. (author)

  4. Fish otolith asymmetry: morphometry and modeling.

    Science.gov (United States)

    Lychakov, D V; Rebane, Y T; Lombarte, A; Fuiman, L A; Takabayashi, A

    2006-09-01

    Mathematical modeling suggests that relatively large values of otolith mass asymmetry in fishes can alter acoustic functionality and may be responsible for abnormal fish behavior when subjected to weightlessness during parabolic or space flight [D.V. Lychakov, Y.T. Rebane, Otolith mass asymmetry in 18 species of fish and pigeon, J. Grav. Physiol. 11 (3) (2004) 17-34; D.V. Lychakov, Y.T. Rebane, Fish otolith mass asymmetry: morphometry and influence on acoustic functionality, Hear. Res. 201 (2005) 55-69]. The results of morphometric studies of otolith mass asymmetry suppose that the absolute value and the sign of the otolith mass asymmetry can change many times during the growth of individual fish within the range +/-20% [D.V. Lychakov, Y.T. Rebane, Otolith mass asymmetry in 18 species of fish and pigeon, J. Grav. Physiol. 11 (3) (2004) 17-34; D.V. Lychakov, Y.T. Rebane, Fish otolith mass asymmetry: morphometry and influence on acoustic functionality, Hear. Res. 201 (2005) 55-69]. This implies that the adverse effects of otolith asymmetry on acoustic and vestibular functionality could change during the lifetime of an individual fish. The aims of the present article were to examine the nature of otolith mass asymmetry fluctuation and to quantify otolith mass asymmetry in a large number of teleost fishes to verify our previous measurements. A dimensionless measure of otolith mass asymmetry, chi, was calculated as the difference between the masses of the right and left paired otoliths divided by average otolith mass. Saccular otolith mass asymmetry was studied in 59 Mediterranean teleost species (395 otolith pairs), 14 Black Sea teleost species (42 otolith pairs), red drum (196 otolith pairs) and guppy (30 otolith pairs). Utricular otolith mass asymmetry was studied in carp (103 otolith pairs) and goldfish (45 otolith pairs). In accordance with our previous results the value of chi did not depend on fish size (length or mass), systematic or ecological position of the

  5. Fish movement and dietary history derived from otolith δ13C

    Science.gov (United States)

    Weber, P. K.; Finlay, J. C.; Power, M. E.; Phillis, C. C.; Ramon, C. E.; Eaton, G. F.; Ingram, B. L.

    2005-12-01

    Habitat use and food web linkages are critical data for fish conservation and habitat restoration efforts, particularly for threatened salmonids species. Otolith microchemistry has been shown to be a powerful tool for reconstructing fish movement, but over small distances (kilometers), geology-derived differences in otolith chemistry are rare. Here, we demonstrate that otolith 13C/12C ratio (i.e. δ13C) of anadromous steelhead trout can be used to distinguish residence in small streams from residence in larger streams and rivers. While previous research has shown that water dissolved inorganic carbon d13C is the primary source of carbon in otoliths, the downstream change in food δ13C in this watershed appears to be the primary control on otolith δ13C. As a result, this method can also be applied to the problem of reconstructing feeding history at a location.

  6. Fish Movement and Dietary History Derived from Otolith (delta)13C

    Energy Technology Data Exchange (ETDEWEB)

    Weber, P K; Finlay, J C; Power, M E; Phillis, C C; Ramon, C E; Eaton, G F; Ingram, B L

    2005-09-08

    Habitat use and food web linkages are critical data for fish conservation and habitat restoration efforts, particularly for threatened salmonids species. Otolith microchemistry has been shown to be a powerful tool for reconstructing fish movement, but over small distances (kilometers), geology-derived differences in otolith chemistry are rare. Here, we demonstrate that otolith {sup 13}C/{sup 12}C ratio (i.e. {delta}{sup 13}C) of anadromous steelhead trout can be used to distinguish residence in small streams from residence in larger streams and rivers. While previous research has shown that water dissolved inorganic carbon {delta}{sup 13}C is the primary source of carbon in otoliths, the downstream change in food {delta}{sup 13}C in this watershed appears to be the primary control on otolith {delta}{sup 13}C. As a result, this method can also be applied to the problem of reconstructing feeding history at a location.

  7. EPR study of sagitta otoliths of Sciaenidae fish

    International Nuclear Information System (INIS)

    otoliths crystallization process seems to be controlled by an endogenous mechanism that is common to these two fish species

  8. EPR study of sagitta otoliths of Sciaenidae fish

    Energy Technology Data Exchange (ETDEWEB)

    Beneditto, Ana Paula Madeira di; Franco, Roberto Weider de Assis [Universidade Estadual do Norte Fluminense (UENF), RJ (Brazil)

    2011-07-01

    are living. Then, we can infer that the sagitta otoliths crystallization process seems to be controlled by an endogenous mechanism that is common to these two fish species

  9. Magnetic elements in otoliths of lagena and their function

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Yasuo [Hiroshima City Hospital Affairs Bureau, Hiroshima (Japan)

    2002-07-01

    The mystery of pigeons' homing abilities has been the subject of much interest, and it is widely believed that information from the earth's magnetic field may be involved. However, no specific magnetic sensory organ has yet been identified. The recent finding of magnetic materials in the lagenal otolith of fishes and birds raises the possibility that these structures might be key elements in the elusive magnetic sensor system. For the elemental analysis inside materials, x-ray fluorescence method (Synchrotron radiation) is one of the most powerful techniques. BL4A beam line of Photo factory of KEK at Tsukuba was used for analysis of the otolith. Comparing the compositions of the three different kinds of otolith among several species of sea fishes and birds, we found that the saccular and utricular otolith rarely contain detectable levels of Fe (iron), but that Fe is present in significant quantities in the lagenal otolith of the birds. The lagenal otolith is tiny crystal that contains magnetic elements and is sensitively displaced by imposed magnetic fields, providing the animal with geomagnetic sensory input, from which the brain would infer navigational information. Behavioral experiments of the homing abilities of the pigeons involving sectioning the lagenal nerves and the magnetic interfere to their lagena were done using 30 controlled birds and 21 treated birds from the same loft of the racing pigeons. The result of homing test of the control and treated pigeons clearly indicates the magnetic influence and lagenal function to pigeon's navigation ability, and the treated pigeons were either lost or significantly delayed, while the controls returned within 30 minutes after the release. Thus the birds' lagena is unique organ, and it may be concluded that the lagena is a key element to magnetic sensory system for birds. (author)

  10. Magnetic elements in otoliths of lagena and their function

    International Nuclear Information System (INIS)

    The mystery of pigeons' homing abilities has been the subject of much interest, and it is widely believed that information from the earth's magnetic field may be involved. However, no specific magnetic sensory organ has yet been identified. The recent finding of magnetic materials in the lagenal otolith of fishes and birds raises the possibility that these structures might be key elements in the elusive magnetic sensor system. For the elemental analysis inside materials, x-ray fluorescence method (Synchrotron radiation) is one of the most powerful techniques. BL4A beam line of Photo factory of KEK at Tsukuba was used for analysis of the otolith. Comparing the compositions of the three different kinds of otolith among several species of sea fishes and birds, we found that the saccular and utricular otolith rarely contain detectable levels of Fe (iron), but that Fe is present in significant quantities in the lagenal otolith of the birds. The lagenal otolith is tiny crystal that contains magnetic elements and is sensitively displaced by imposed magnetic fields, providing the animal with geomagnetic sensory input, from which the brain would infer navigational information. Behavioral experiments of the homing abilities of the pigeons involving sectioning the lagenal nerves and the magnetic interfere to their lagena were done using 30 controlled birds and 21 treated birds from the same loft of the racing pigeons. The result of homing test of the control and treated pigeons clearly indicates the magnetic influence and lagenal function to pigeon's navigation ability, and the treated pigeons were either lost or significantly delayed, while the controls returned within 30 minutes after the release. Thus the birds' lagena is unique organ, and it may be concluded that the lagena is a key element to magnetic sensory system for birds. (author)

  11. Effect of ocean acidification on otolith development in larvae of a tropical marine fish

    Science.gov (United States)

    Munday, P. L.; Hernaman, V.; Dixson, D. L.; Thorrold, S. R.

    2011-06-01

    Calcification in many invertebrate species is predicted to decline due to ocean acidification. The potential effects of elevated CO2 and reduced carbonate saturation state on other species, such as fish, are less well understood. Fish otoliths (earbones) are composed of aragonite, and thus, might be susceptible to either the reduced availability of carbonate ions in seawater at low pH, or to changes in extracellular concentrations of bicarbonate and carbonate ions caused by acid-base regulation in fish exposed to high pCO2. We reared larvae of the clownfish Amphiprion percula from hatching to settlement at three pHNBS and pCO2 levels (control: ~pH 8.15 and 404 μatm CO2; intermediate: pH 7.8 and 1050 μatm CO2; extreme: pH 7.6 and 1721 μatm CO2) to test the possible effects of ocean acidification on otolith development. There was no effect of the intermediate treatment (pH 7.8 and 1050 μatm CO2) on otolith size, shape, symmetry between left and right otoliths, or otolith elemental chemistry, compared with controls. However, in the more extreme treatment (pH 7.6 and 1721 μatm CO2) otolith area and maximum length were larger than controls, although no other traits were significantly affected. Our results support the hypothesis that pH regulation in the otolith endolymph can lead to increased precipitation of CaCO3 in otoliths of larval fish exposed to elevated CO2, as proposed by an earlier study, however, our results also show that sensitivity varies considerably among species. Importantly, our results suggest that otolith development in clownfishes is robust to even the more pessimistic changes in ocean chemistry predicted to occur by 2100.

  12. Clinical verification of a unilateral otolith test

    Science.gov (United States)

    Wetzig, J.; Hofstetter-Degen, K.; Maurer, J.; von Baumgarten, R. J.

    In a previous study 13 we reported promising results for a new test to differentiate in vivo unilateral otolith functions. That study pointed to a need for further validation on known pathological cases. In this presentation we will detail the results gathered on a group of clinically verified vestibular defectives (verum) and a normal (control) group. The subjects in the verum group were former patients of the ENT clinic of the university hospital. These subjects had usually suffered from neurinoma of the VIIth cranial nerve or inner ear infections. All had required surgical intervention including removal of the vestibular system. The patients were contacted usually two or more years postoperatively. A group of students from the pre- and clinical phase of medical training served as control. Both groups were subjected to standardized clinical tests. These tests served to reconfirm the intra- or postoperative diagnosis of unilateral vestibular loss in the verum group. In the control group they had to establish the normalcy of the responses of the vestibular system. Both groups then underwent testing on our exccentric rotary chair in the manner described before 13. Preliminary results of the trials indicate that this test may indeed for the first time offer a chance to look at isolated otolith apparati in vivo.

  13. X-ray diffraction, XAFS and scanning electron microscopy study of otolith of a crevalle jack fish (caranx hippos)

    Energy Technology Data Exchange (ETDEWEB)

    Pattanaik, Sidhartha [Bailey Hall 703, Illinois Institute of Technology, 3101 S. Wabash Avenue, Chicago, IL 60616 (United States)]. E-mail: sidpattanaik@yahoo.com

    2005-04-01

    The otolith of a crevalle jack fish (caranx hippos) has been investigated by means of X-ray diffraction, X-ray absorption fine structure spectroscopy and scanning electron microscopy techniques. The results suggest that the biomineralization of otolith occurs predominantly in the aragonite phase. A detailed X-ray Rietveld analysis showed that the first shell Ca-O distances in otolith lay in the range 2.371-2.652 A, with each calcium atom coordinated to 9 oxygen atoms. While the average Ca-O distance remains same in both otolith and aragonite, certain Ca-O distances in otolith differ markedly from those in aragonite. Such difference reflects the remarkable degree of control that the protein matrix exercised over packing of calcium and carbonate ions to promote growth of rarer aragonite otolith. In view of the complex coordination chemistry of calcium in otoliths, the EXAFS analysis was limited to obtaining local atomic environment about calcium up to the first Ca-O shell. EXAFS data showed an asymmetric distribution of Ca-O bond distances with the centroid of distribution at 2.48 A, which is closer to the average Ca-O distance in aragonite than in calcite. The asymmetry in the Ca-O peak is consistent with an apparent departure of Ca-O distances from a near regular distribution, as expected of an aragonite otolith.

  14. X-ray diffraction, XAFS and scanning electron microscopy study of otolith of a crevalle jack fish (caranx hippos)

    International Nuclear Information System (INIS)

    The otolith of a crevalle jack fish (caranx hippos) has been investigated by means of X-ray diffraction, X-ray absorption fine structure spectroscopy and scanning electron microscopy techniques. The results suggest that the biomineralization of otolith occurs predominantly in the aragonite phase. A detailed X-ray Rietveld analysis showed that the first shell Ca-O distances in otolith lay in the range 2.371-2.652 A, with each calcium atom coordinated to 9 oxygen atoms. While the average Ca-O distance remains same in both otolith and aragonite, certain Ca-O distances in otolith differ markedly from those in aragonite. Such difference reflects the remarkable degree of control that the protein matrix exercised over packing of calcium and carbonate ions to promote growth of rarer aragonite otolith. In view of the complex coordination chemistry of calcium in otoliths, the EXAFS analysis was limited to obtaining local atomic environment about calcium up to the first Ca-O shell. EXAFS data showed an asymmetric distribution of Ca-O bond distances with the centroid of distribution at 2.48 A, which is closer to the average Ca-O distance in aragonite than in calcite. The asymmetry in the Ca-O peak is consistent with an apparent departure of Ca-O distances from a near regular distribution, as expected of an aragonite otolith

  15. X-ray diffraction, XAFS and scanning electron microscopy study of otolith of a crevalle jack fish ( caranx hippos)

    Science.gov (United States)

    Pattanaik, Sidhartha

    2005-04-01

    The otolith of a crevalle jack fish (caranx hippos) has been investigated by means of X-ray diffraction, X-ray absorption fine structure spectroscopy and scanning electron microscopy techniques. The results suggest that the biomineralization of otolith occurs predominantly in the aragonite phase. A detailed X-ray Rietveld analysis showed that the first shell Ca-O distances in otolith lay in the range 2.371-2.652 Å, with each calcium atom coordinated to 9 oxygen atoms. While the average Ca-O distance remains same in both otolith and aragonite, certain Ca-O distances in otolith differ markedly from those in aragonite. Such difference reflects the remarkable degree of control that the protein matrix exercised over packing of calcium and carbonate ions to promote growth of rarer aragonite otolith. In view of the complex coordination chemistry of calcium in otoliths, the EXAFS analysis was limited to obtaining local atomic environment about calcium up to the first Ca-O shell. EXAFS data showed an asymmetric distribution of Ca-O bond distances with the centroid of distribution at 2.48 Å, which is closer to the average Ca-O distance in aragonite than in calcite. The asymmetry in the Ca-O peak is consistent with an apparent departure of Ca-O distances from a near regular distribution, as expected of an aragonite otolith.

  16. Fish otolith mass asymmetry: morphometry and influence on acoustic functionality.

    Science.gov (United States)

    Lychakov, D V; Rebane, Y T

    2005-03-01

    The role of the fish otolith mass asymmetry in acoustic functionality is studied. The saccular, lagenar and utricular otoliths are weighted in two species of the Black Sea rays, 15 species of the Black Sea teleost fish and guppy fish. The dimensionless otolith mass asymmetry chi is calculated as ratio of the difference between masses of the right and left paired otoliths to average otolith mass. In the most fish studied the otolith mass asymmetry is within the range of -0.2 < chi < +0.2 (< 20%). We do not find specific fish species with extremely large or extremely small otolith asymmetry. The large otoliths do not belong solely to any particular side, left or right. The heavier otoliths of different otolithic organs can be located in different labyrinths. No relationship has been found between the magnitude of the otolith mass asymmetry and the length (mass, age) of the animal. The suggested fluctuation model of the otolith growth can interpret these results. The model supposes that the otolith growth rate varies slightly hither and thither during lifetime of the individual fish. Therefore, the sign of the relative otolith mass asymmetry can change several times in the process of the individual fish growth but within the range outlined above. Mathematical modeling shows that acoustic functionality (sensitivity, temporal processing, sound localization) of the fish can be disturbed by the otolith mass asymmetry. But this is valid only for the fish with largest otolith masses, characteristic of the bottom and littoral fish, and with highest otolith asymmetry. For most fish the values of otolith mass asymmetry is well below critical values. Thus, the most fish get around the troubles related to the otolith mass asymmetry. We suggest that a specific physicochemical mechanism of the paired otolith growth that maintains the otolith mass asymmetry at the lowest possible level should exist. However, the principle and details of this mechanism are still far from being

  17. Decreased otolith-mediated vestibular response in 25 astronauts induced by long-duration spaceflight.

    Science.gov (United States)

    Hallgren, Emma; Kornilova, Ludmila; Fransen, Erik; Glukhikh, Dmitrii; Moore, Steven T; Clément, Gilles; Van Ombergen, Angelique; MacDougall, Hamish; Naumov, Ivan; Wuyts, Floris L

    2016-06-01

    The information coming from the vestibular otolith organs is important for the brain when reflexively making appropriate visual and spinal corrections to maintain balance. Symptoms related to failed balance control and navigation are commonly observed in astronauts returning from space. To investigate the effect of microgravity exposure on the otoliths, we studied the otolith-mediated responses elicited by centrifugation in a group of 25 astronauts before and after 6 mo of spaceflight. Ocular counterrolling (OCR) is an otolith-driven reflex that is sensitive to head tilt with regard to gravity and tilts of the gravito-inertial acceleration vector during centrifugation. When comparing pre- and postflight OCR, we found a statistically significant decrease of the OCR response upon return. Nine days after return, the OCR was back at preflight level, indicating a full recovery. Our large study sample allows for more general physiological conclusions about the effect of prolonged microgravity on the otolith system. A deconditioned otolith system is thought to be the cause of several of the negative effects seen in returning astronauts, such as spatial disorientation and orthostatic intolerance. This knowledge should be taken into account for future long-term space missions. PMID:27009158

  18. Assessing Essential Fish Habitat in Freshwater Environments Using Otolith Chemistry: Spring River, AR.

    Science.gov (United States)

    Bickford, N. A.; Hamilton, B.; Hannigan, R. E.

    2002-12-01

    The identification of essential fish habitat within freshwater systems is critical to the management of the game fish populations. In order to accurately assess habitat we investigated the physical and chemical hydrological controls on game fish abundances and distributions with the 92-km reach of the Spring River of Arkansas. The hydrology of the river was integrated in to the chemical analyses of otolith chemistry of game fish from habitats throughout the river. Identified spatial and temporal variations in metal concentration within the Spring River are an important factor in the recognition of essential fish habitat. In the Spring River, where spatial and temporal metal concentration variations are significant, otolith chemistry has the potential to serve as a marker of essential habitat in much the same way as in estuarine and marine settings. Using otolith chemistry to identify essential habitat in freshwater systems has the potential to revolutionize ecological management strategies. Fish otolith chemistry shows both inter-species variations and spatial variations. Spatial variations in the otolith chemistry as recorded over the life of the fish allow identification of the nursery habitat and feeding range of game fish. Using otolith chemistry, particularly variations in trace element composition rather than the traditional major element ratios (i.e., Mg/Ca), we are able to identify essential habitats and provide managers data needed for conservation and preservation of these habitats.

  19. Ultrastructural aspects of otoliths and sensory epithelia of fish inner ear exposed to hypergravity

    Science.gov (United States)

    Ibsch, M.; Nindl, G.; Anken, R. H.; Körtje, K. H.; Rahmann, H.

    The present electron microscopical investigations were directed to the question, whether alterations in the gravitational force might induce structural changes in the morphology of otoliths or/and inner ear sensory epithelia of developing and adult swordtail fish (Xiphophorus helleri) that had been kept either under long-term moderate hypergravity (8 days; 3g) or under short-time extreme hypergravity (10 minutes up to 9g). The otoliths of adult and neonate swordtail fish were investigated by means of scanning electron microscopy (SEM). Macular epithelia of adult fish were examined both by SEM and transmission electron microscopy (TEM). The saccular otoliths (sagittae) of normally hatched adult fish revealed an enormous inter- (and even intra-; i.e. left vs. right) individual diversity in shape and size, whereas the otoliths of utricles (lapilli) and lagenae (asterisci) seemed to be more constant regarding morphological parameters. The structural diversity of juvenile otoliths was found to be less prominent as compared to the adults, differing from the latter regarding their peculiar crystalline morphology. Qualitative differences in the fine structure (SEM) of otoliths taken from adult and larval animals kept under 3g in comparison to 1g controls could not be observed. The SEM and TEM investigations of sensory epithelia also did not reveal any effects due to 3g stimulation. Even extreme hypergravity (more than 7g) for 10 minutes did not result in distinct pathological changes.

  20. Facilitation of barium uptake into fish otoliths: Influence of strontium concentration and salinity

    Science.gov (United States)

    de Vries, Melita C.; Gillanders, Bronwyn M.; Elsdon, Travis S.

    2005-08-01

    To reconstruct patterns of fish migration using otolith chemistry, it is essential to validate the relationship between elements in otoliths and the surrounding water, and in particular, how processes such as competition and facilitation among multiple elements influence otolith chemistry. Using a controlled laboratory experiment, juvenile black bream ( Acanthopagrus butcheri) were reared in both brackish and seawater spiked with different concentrations of Sr and Ba. The addition of Sr to the solution facilitated the uptake of Ba into otoliths of fish reared in brackish water, but not in seawater. Conversely, Ba did not facilitate nor compete with the uptake of Sr in either brackish or seawater. In brackish water, Sr incorporation into otoliths may create crystal defects within the CaCO 3 matrix, enabling greater incorporation of Ba. Ba:Ca partition coefficients (D Ba) for brackish and seawater were 0.058 and 0.136, respectively, whereas Sr:Ca partition coefficients (D Sr) for brackish and seawater were 0.463 and 0.287, respectively. The influence of Sr on Ba incorporation in fish otoliths is important to consider when reconstructing migration histories of fish, especially in brackish water environments.

  1. Dating hapuka otoliths using 210 Pb/226 Ra, with comments on dating orange roughy otoliths

    International Nuclear Information System (INIS)

    It is shown that Hapuka otoliths cannot be reliably dated using the 210 Pb/ 226 Ra method because contrary to previous assumptions, excess 210 Pb is incorporated into the outer layers of otoliths which have been taken from old fish, though the 226 Ra incorporation remains normal. This is shown to apply also to Orange Roughy otoliths. Ages based on calculations using previously published methods will be artificially old. (author). 13 refs., 2 tabs., 3 figs

  2. Radiocarbon Values From Otoliths of Regional Bottomfishes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains bomb radiocarbon dating of opakapaka (Pristipomoides filamentosus) otoliths from recent and archival collections (1978-2008). Specimens were...

  3. Factors determining δ13C and δ18O fractionation in aragonitic otoliths of marine fish

    Science.gov (United States)

    Thorrold, Simon R.; Campana, Steven E.; Jones, Cynthia M.; Swart, Peter K.

    1997-07-01

    Fish otoliths are aragonitic accretions located within the inner ear of teleost fish. The acellular nature of otoliths, along with taxon-specific shapes, chronological growth increments, and abundance in the fossil record suggest that the stable isotope chemistry of these structures may be unique recorders of environmental conditions experienced by fish in both modern and ancient water masses. To assess the factors determining δ 13C and δ 18O fractionation in fish otoliths, we reared Atlantic croaker ( Micropogonias undulatus) larvae under controlled environmental conditions. Metabolic effects apparently generated large isotopic disequilibria in the δ 13C values of M. undulatus otoliths. We found evidence of a negative regression between δ 13C- carbonate-δ 13C water (δ 13C) and temperature: δ 13C = -1.78 - 0.18 T °C However, this relationship was aliased to a degree by a positive correlation between δ 13C and somatic growth and otolith precipitation rates. Oxygen isotopes were deposited close to equilibrium with the ambient water. The relationship between temperature and the 18O/ 16O fractionation factor (α) was determined empirically to be: 1000 ln α = 18.56(10 3T K -1) - 32.54 The fractionation factor was not affected by either otolith precipitation or fish growth rates. Reconstruction of water temperature histories should, therefore, be possible from the δ 18O values of M. undulatus otoliths with a precision of 1°C, providing the δ 18O of the ambient water can be estimated.

  4. Effect of ocean acidification on otolith development in larvae of a tropical marine fish

    Directory of Open Access Journals (Sweden)

    P. L. Munday

    2011-03-01

    Full Text Available Calcification in many invertebrate species is predicted to decline due to ocean acidification. The potential effects of elevated pCO2 and reduced carbonate saturation state on other species, such as fish, are less well understood. Fish otoliths (earbones are composed of aragonite, and thus, might be susceptible to either the reduced availability of carbonate ions in seawater at low pH, or to changes in extracellular concentrations of bicarbonate and carbonate ions caused by acid-base regulation in fish exposed to high pCO2. We reared larvae of the clownfish Amphiprion percula from hatching to settlement at three pHNBS and pCO2 levels (control: pH 8.15 and 404 μatm CO2; intermediate: pH 7.8 and 1050 μatm CO2; extreme: pH 7.6 and 1721 μatm CO2 to test the possible effects of ocean acidification on otolith development. There was no effect of the intermediate treatment (pH 7.8 and 1050 μatm CO2 on otolith size, shape, symmetry between left and right otoliths, or otolith elemental chemistry, compared with controls. However, in the more extreme treatment (pH 7.6 and 1721 μatm CO2 otolith area and maximum length were larger than controls, although no other traits were affected. Our results support the hypothesis that pH regulation in the otolith endolymph of fish exposed to elevated pCO2 can lead to increased precipitation of CaCO3 in otoliths of larval fish, as proposed by an earlier study, however, our results also show that sensitivity varies considerably among species. Importantly, our results suggest that otolith development in clownfishes is robust to even the more pessimistic changes in ocean chemistry predicted to occur by 2100.

  5. Effect of ocean acidification on otolith development in larvae of a tropical marine fish

    Directory of Open Access Journals (Sweden)

    P. L. Munday

    2011-06-01

    Full Text Available Calcification in many invertebrate species is predicted to decline due to ocean acidification. The potential effects of elevated CO2 and reduced carbonate saturation state on other species, such as fish, are less well understood. Fish otoliths (earbones are composed of aragonite, and thus, might be susceptible to either the reduced availability of carbonate ions in seawater at low pH, or to changes in extracellular concentrations of bicarbonate and carbonate ions caused by acid-base regulation in fish exposed to high pCO2. We reared larvae of the clownfish Amphiprion percula from hatching to settlement at three pHNBS and pCO2 levels (control: ~pH 8.15 and 404 μatm CO2; intermediate: pH 7.8 and 1050 μatm CO2; extreme: pH 7.6 and 1721 μatm CO2 to test the possible effects of ocean acidification on otolith development. There was no effect of the intermediate treatment (pH 7.8 and 1050 μatm CO2 on otolith size, shape, symmetry between left and right otoliths, or otolith elemental chemistry, compared with controls. However, in the more extreme treatment (pH 7.6 and 1721 μatm CO2 otolith area and maximum length were larger than controls, although no other traits were significantly affected. Our results support the hypothesis that pH regulation in the otolith endolymph can lead to increased precipitation of CaCO3 in otoliths of larval fish exposed to elevated CO2, as proposed by an earlier study, however, our results also show that sensitivity varies considerably among species. Importantly, our results suggest that otolith development in clownfishes is robust to even the more pessimistic changes in ocean chemistry predicted to occur by 2100.

  6. On the influence of altered gravity on the growth of fish inner ear otoliths

    Science.gov (United States)

    Beier, Marion

    1999-09-01

    Inner ear stones (otoliths) of developing cichlid fish ( Oreochromis mossambicus) were marked with the calcium tracer alizarin-complexone (AC) at 1g-earth gravity before and after a long-term (20 days) stay of the animals at moderate hypergravity conditions (3g; centrifuge). AC deposition at the otoliths resulted in two fluorescence bands, which enclosed the area grown during exposure to altered gravity. This area was measured with regard to size and asymmetry (size difference between the left and the right stones). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens. The asymmetry concerning the lapilli was pronouncedly decreased in comparison to the 1g-controls. These findings suggest, that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector. Some of the hyper-g animals revealed a kinetotic behaviour at the transfer from hyper-g to normal 1g-earth gravity conditions, which was qualitatively similar to the behaviour observed in previous experiments at the transfer from 1g to microgravity in the course of parabolic aircraft flights. The lapillar asymmetry of kinetotic samples was found to be significantly higher than that of normally behaving experimental specimens. This result supports an earlier theoretical concept, according to which human static space sickness might be based on asymmetric utricular otoliths.

  7. Influence of hypergravity on fish inner ear otoliths: I. Developmental growth profile

    Science.gov (United States)

    Anken, R. H.; Beier, M.; Rahmann, H.

    Inner ear stones (otoliths) of larval cichlid fish Oreochromis mossambicus were marked with the calcium-tracer alizarin-complexone (AC) at 1g earth gravity before and after a 3, 7, 14 or 21 days stay of the animals at hypergravity conditions (hg; 3g, centrifuge). After the experiment, the otoliths' area between the two AC-labellings was measured with regard to size and asymmetry (size difference between the left and the right stones). Both utricular and saccular otoliths (lapilli and sagittae, respectively) continued growing in a linear way at hg, but growth was significantly slowed down as compared to parallely raised 1g-control specimens. In case of bilateral asymmetry between the corresponding otoliths its formation in hg-animals became reduced as compared to the 1g controls. The reduction of asymmetry was much more pronounced in the sagittae than in the lapilli. The latter result supports an earlier hypothesis, according to which especially a low sagittal asymmetry has a functional advantage. In general, the results strongly suggest that otolith growth is continuously regulated in dependence of the environmental gravity vector.

  8. The asymmetrical growth of otoliths in fish is affected by hypergravity.

    Science.gov (United States)

    Anken, R. H.; Kappel, T.; Rahmann, H.

    1999-12-01

    Size and asymmetry (size difference between the left and the right side) of inner ear otoliths of larval cichlid fish were determined after a long-term stay at moderate hypergravity conditions (3 g; centrifuge), in the course of which the animals completed their ontogenetic development from hatch to freely swimming. Both the normal morphogenetic development as well as the timely onset and gain of performance of the swimming behaviour was not impaired by the experimental conditions. However, both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper- g exposure as compared to parallely raised 1 g control specimens. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry concerning lapilli was pronouncedly decreased in comparison to the 1 g controls. These findings suggest, that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector.

  9. Identification of a novel matrix protein contained in a protein aggregate associated with collagen in fish otoliths.

    Science.gov (United States)

    Tohse, Hidekazu; Takagi, Yasuaki; Nagasawa, Hiromichi

    2008-05-01

    In the biomineralization processes, proteins are thought to control the polymorphism and morphology of the crystals by forming complexes of structural and mineral-associated proteins. To identify such proteins, we have searched for proteins that may form high-molecular-weight (HMW) aggregates in the matrix of fish otoliths that have aragonite and vaterite as their crystal polymorphs. By screening a cDNA library of the trout inner ear using an antiserum raised against whole otolith matrix, a novel protein, named otolith matrix macromolecule-64 (OMM-64), was identified. The protein was found to have a molecular mass of 64 kDa, and to contain two tandem repeats and a Glu-rich region. The structure of the protein and that of its DNA are similar to those of starmaker, a protein involved in the polymorphism control in the zebrafish otoliths [Söllner C, Burghammer M, Busch-Nentwich E, Berger J, Schwarz H, Riekel C & Nicolson T (2003) Science302, 282-286]. (45)Ca overlay analysis revealed that the Glu-rich region has calcium-binding activity. Combined analysis by western blotting and deglycosylation suggested that OMM-64 is present in an HMW aggregate with heparan sulfate chains. Histological observations revealed that OMM-64 is expressed specifically in otolith matrix-producing cells and deposited onto the otolith. Moreover, the HMW aggregate binds to the inner ear-specific short-chain collagen otolin-1, and the resulting complex forms ring-like structures in the otolith matrix. Overall, OMM-64, by forming a calcium-binding aggregate that binds to otolin-1 and forming matrix protein architectures, may be involved in the control of crystal morphology during otolith biomineralization. PMID:18410381

  10. Inner Ear Otolith Growth in larval Fish after Development at simulated Microgravity

    Science.gov (United States)

    Baur, U.; Hilbig, R.; Anken, R.

    It has been shown earlier that hypergravity slows down inner ear otolith growth in developing fish via a down-regulation of carbonic anhydrase reactivity as an adaptation towards altered environmental gravity We were thus prompted to elucidate whether clinorotation would possibly yield opposite effects Therefore larval siblings of cichlid fish Oreochromis mossambicus were housed in a submersed two-dimensional clinostat Two tubes with different diameters were used 10 5 mm large tube LT and 3 5 mm small tube ST experimental time-span 10 and 7 days respectively After the experiments otoliths were dissected and their size area grown during the experiments was determined planimetrically In case of the LT-clinorotated fish both utricular and saccular otoliths lapilli and sagittae respectively were significantly smaller than those of the 1g-controls In contrast ST-maintenance resulted in significantly larger otoliths lapilli only no statistical significant difference regarding sagittae observed The results from LT-clinorotation therefore indicate that the animals had in fact received hypergravity whereas the ST-data are to be interpreted as being effected by simulated microgravity conditions In conclusion otolith growth is affected by the gravitational vector in a dose-dependent manner Acknowledgement This work was financially supported by the German Aerospace Center DLR FKZ 50 WB 9997

  11. Fish Otolith Growth in 1g and 3g Depends on the Gravity Vector

    Science.gov (United States)

    Anken, R. H.; Werner, K.; Breuer, J.; Rahmann, H.

    Size and asymmetry (size difference between the left and the right side) as well as calcium (Ca) content of inner ear otoliths of larval cichlid fish Oreochromis mossambicus were determined after a long-term stay at hypergravity conditions (3g; centrifuge). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens and the absolute amount of otolith-Ca was diminished. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry concerning lapilli was markedly decreased. In the course of another experiment, larvae were raised in aquarium hatch baskets, from which one was placed directly above aeration equipment, which resulted in random water circulation shifting the fish around (``shifted'' specimens). The lapillar asymmetry of the ``stationary'' specimens showed a highly significant increase during early development when larvae were forced to lay on their sides due to their prominent yolk-sacs. In later developmental stages, when they began to swim freely, a dramatic decrease in lapillar asymmetry was apparent. Taken together with own previous findings according to which otolith growth stops after vestibular nerve transection, the results presented here suggest that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector, obviously involving a feedback loop between the brain and the inner ear

  12. Comparative studies on the influence of "simulated weigthlessness" on fish otolith growth

    Science.gov (United States)

    Brungs, Sonja; Hendrik Anken, Ralf; Li, Xiao-Yan; Hauslage, Jens; Wang, Gaohong; Liu, Yongding; Hilbig, Reinhard; Hemmersbach, Ruth

    Stimulus dependence is a general feature of all developing sensory systems. Concerning the vestibular organ of fish, it has been shown earlier that the growth of inner ear otoliths of developing Cichlid fish (Oreochromis mossambicus) and Zebrafish (Danio rerio) is slowed down by increased gravity (hypergravity) as an adaptation. Several studies proposed that otolith growth actively is adjusted via a feedback mechanism to produce a test mass of the appropriate physical capacity. Applying diminished gravity such as microgravity during spaceflight yielded an opposite effect, i.e., larger than normal otoliths in swordtails Xiphophorus helleri. Since there are no data on spaceflown early larval stages of the Cichlid fish and the Zebrafish available, these model organisms were subjected to simulated weightlessness using a submersed clinostat with one axis of rotation (O. mossambicus) and rotating-wall vessels (RWVs; O. mossambicus was maintained within a submersed RWV, which was recently developed at DLR, whereas D. rerio was kept within a modified RWV, developed by NASA). Developmental stages were subjected to clinorotation (60 rpm) and wall vessel rotation (Cichlid fish: 44 rpm; Zebrafish: 12.5 rpm; at these speeds, the larvae did neither sediment nor were they centrifuged away from the center of the RWVs) at a point of time when inner ear otolith mineralisation began. The experimental runs were discontinued when the animals hatched (O. mossambicus, stage 12, reached after 2-3 days at 22° C) or when they began to actively move within the devices (D. rerio, after 6 days at 28° C). After clinostat exposure, both utricular and saccular otoliths (Lapilli and Sagittae, respectively) of the Cichlids were significantly larger as compared to otoliths from the 1g controls. A similar result was obtained after wall vessel rotation for 3 and 6 days of the Zebrafish. These results support the idea that a feedback mechanism correlates the gravity level with the physical capacity

  13. Effect of hypergravity on the Ca/Sr composition of developing otoliths of larval cichlid fish (Oreochromis mossambicus).

    Science.gov (United States)

    Anken, R H; Ibsch, M; Breuer, J; Rahmann, H

    2001-02-01

    The amounts of calcium and strontium were measured by inductively coupled plasma mass spectrometry (ICP-MS) in saccular and utricular inner ear otoliths (sagittae and lapilli, respectively) of developing cichlid fish. These fish had been maintained for 22 days at 3-g hypergravity conditions within a centrifuge. During this time-span, the animals completed their ontogenetic development from hatch to the free-swimming stage. Neither the morphogenetic development nor the timely onset and gain of performance of the swimming behaviour was impaired by the experimental conditions. Experimental and control animals also did not differ concerning their size (total length). ICP-MS revealed that the otoliths contained significantly less calcium (in microg/otolith) after hyper-g exposure compared to parallelly raised 1-g control specimens (lapilli: 0.74+/-0.21 vs. 1.16+/-0.41; sagittae: 2.09+/-0.49 vs. 2.76+/-0.47). The content of strontium (in microg/otolith: lapilli: 0.0044+/-0.0023 vs. 0.0022+/-0.0013; sagittae: 0.0094+/-0.0026 vs. 0.0081+/-0.0016) and, consequently, the Sr/Ca ratio (Sr/Cax100) was increased (lapilli: 0.607+/-0.267 vs. 0.201+/-0.12; sagittae: 0.439+/-0.093 vs. 0.301+/-0.086). Since the calcium content can be taken as a proxy for otolith weight, and because parallelly undertaken morphometric investigations revealed smaller otoliths (maximum radius and surface area) due to hyper-g exposure, the results suggest that the growth of otoliths at hyper-g is slowed down. Since the concentration of trace elements incorporated into otoliths is likely based on the composition of the respective protein matrix, our findings suggest that the protein metabolism is affected by hypergravity. PMID:11223398

  14. Human otolith function, experiment M009

    Science.gov (United States)

    Graybiel, A.; Miller, E. F., II

    1971-01-01

    The experiments that were performed during the Gemini 5 and 7 missions resulted in quantitative information concerning otolithic function and orientation of four subjects exposed to an orbiting spacecraft environment for prolonged periods of time. Preflight counterrolling measurements revealed significant differences between crewmembers with regard to the basic magnitude of otolith response. However, after the flight, each crewmember maintained his respective preflight level of response. This was indicative that no significant change in otolithic sensitivity occurred as a result of the flight, or at least no change persisted long enough to be recorded several hours after recovery. The EVLH data recorded for each subject confirmed the observation that a coordinate space sense exists even in a weightless environment if contact cues are adequate. However, it was noted that the apparent location of the horizontal within the spacecraft may not agree necessarily with its physical correlate in the spacecraft.

  15. Estimating population age structure using otolith morphometrics

    DEFF Research Database (Denmark)

    Doering-Arjes, P.; Cardinale, M.; Mosegaard, Henrik

    2008-01-01

    known-age fish individuals. Here we used known-age Atlantic cod (Gadus morhua) from the Faroe Bank and Faroe Plateau stocks. Cod populations usually show quite large variation in growth rates and otolith shape. We showed that including otolith morphometrics into ageing processes has the potential to...... make ageing objective, accurate, and fast. Calibration analysis indicated that a known-age sample from the same population and environment is needed to obtain robust calibration; using a sample from a different stock more than doubles the error rate, even in the case of genetically highly related...... populations. The intercalibration method was successful but generalization from one stock to another remains problematic. The development of an otolith growth model is needed for generalization if an operational method for different populations is required in the future....

  16. Can analysis of Platichthys flesus otoliths provide relevant data on historical metal pollution in estuaries? Experimental and in situ approaches.

    Science.gov (United States)

    Selleslagh, Jonathan; Echard, Aurélie; Pécheyran, Christophe; Baudrimont, Magalie; Lobry, Jérémy; Daverat, Françoise

    2016-07-01

    Despite recent efforts to manage them more efficiently, estuaries are natural sinks for a wide range of metal contaminants, many of which accumulate at potentially toxic concentrations for fish populations, posing a threat to recruitment and stocks. While analysis of metal concentrations in soft tissue and water samples calls for continuous and long-term sampling operations, the use of otoliths to study metal pollution may be one way of providing a historical record of pollutant exposure. In this study, we examine the potential use of otoliths as natural tracers of metal contamination. A "cocktail" of different metals (Cd, Pb and Ni) was used to test bio-accumulation in otoliths and tissue (liver, kidney, muscle and gills) extracted from juvenile flounder (Platichthys flesus). Assessment took place under controlled conditions over a three month period, with water exposure concentrations increasing every 3weeks. The concentrations used were natural (T1), X5 (T2), X10 (T3), and null (T4). Chemical analyses were carried out using an inductively coupled plasma optical emission spectrometer ICP-OES and atomic absorption spectrometer AAS for water and tissue, while otolith microchemistry analyses were performed using a femtosecond laser ablation-high resolution inductively coupled plasma mass spectrometer (fsLA-ICP-MS-HR). Significant differences between control and exposed individuals, as well as an increase in metal concentrations according to exposure level, were observed in all tissues except in muscle tissue. Significant increases in Pb were also detected in contaminated fish otoliths compared with control specimens, with the highest concentrations occurring in T3. Cartographies of Pb distribution in otoliths of both control and contaminated fish only showed high concentrations of Pb at the edge of contaminated fish otoliths, indicating an accumulation of metal during the experiment. Although the relationships between exposure level and Pb concentration in otoliths

  17. Fish Otoliths as indicators: results of the V International Otolith Symposium (IOS2014

    Directory of Open Access Journals (Sweden)

    Audrey J. Geffen

    2015-11-01

    The traditional approach of using calcified tissues to determine fish age and therefore to determine the fish population structure has been augmented by new applications to address questions of population connectivity, migrations, and trophic ecology. These tools have become increasingly important as we transition to spatially explicit and ecosystem-level management tools. They are now extended to applications related to spatial use (essential habitats and to the use of otoliths as a record of past and present environmental conditions. Otoliths are valuable as individual bio-recorders, and – as demonstrated in the variety of presentations at the symposium – also as indicators for higher levels of organisation. The increased appreciation for otolith archives was also apparent; taking advantage of the extended otolith sampling for stock assessment and providing ample collections from different species, as well as from the fossil records.

  18. The OTOLITH Experiment - Assessment of Otolith Function During Postflight Re-adaption

    Science.gov (United States)

    Clarke, A. H.; Wood, S. J.; Schoenfeld, U.

    2010-01-01

    The ongoing "Otolith" experiment is designed to comprehensively assess the otolith function during the re-adaptation phase after spaceflight. The novel protocol includes unilateral testing of each of the two otolith organs the utricle and the saccule. To assess utricle function, the otolith-ocular response (OOR) and the subjective visual vertical (SVV) are measured during unilateral centrifugation, which permits independent stimulation of the right and left ear. Measurement of the unilateral otolith-ocular response (uOOR) yields information on the response behaviour of the right and left peripheral utricles, whereas the SVV reflects the behaviour of the entire pathway from the peripheral otolith receptors to the vestibular cortex. Thus, by comparative evaluation of the results from the two tests, the degree of peripheral versus central adaptation during the post-flight period can be determined. To assess unilateral saccule function, vestibular evoked myogenic potentials (VEMP) are recorded. Since the saccules are predominantly aligned to gravity, and interplay with the antigravity muscles, it is hypothesised that these potentials shall be altered after spaceflight. To date the study has been conducted with 5 of a planned 8 short-flight Shuttle astronauts. Preliminary results will be discussed together with those from clinical studies of dizziness patients, where the same test protocol is employed. ACKNOWLEDGEMENT This work is supported by the German Aerospace Center (Grant DLR W130729) and is conducted under the auspices of ESA, in cooperation with NASA.

  19. Not All Inner Ears are the Same: Otolith Matrix Proteins in the Inner Ear of Sub-Adult Cichlid Fish, Oreochromis Mossambicus, Reveal Insights Into the Biomineralization Process.

    Science.gov (United States)

    Weigele, Jochen; Franz-Odendaal, Tamara A; Hilbig, Reinhard

    2016-02-01

    The fish ear stones (otoliths) consist mainly of calcium carbonate and have lower amounts of a proteinous matrix. This matrix consists of macromolecules, which directly control the biomineralization process. We analyzed the composition of this proteinous matrix by mass spectrometry in a shotgun approach. For this purpose, an enhanced protein purification technique was developed that excludes any potential contamination of proteins from body fluids. Using this method we identified eight proteins in the inner ear of Oreochromis mossambicus. These include the common otolith matrix proteins (OMP-1, otolin-1, neuroserpin, SPARC and otoconin), and three proteins (alpha tectorin, otogelin and transferrin) not previously localized to the otoliths. Moreover, we were able to exclude the occurrence of two matrix proteins (starmaker and pre-cerebellin-like protein) known from other fish species. In further analyses, we show that the absence of the OMP starmaker corresponds to calcitic otoliths and that pre-cerebellin-like protein is not present at any stage during the development of the otoliths of the inner ear. This study shows O. mossambicus does not have all of the known otolith proteins indicating that the matrix proteins in the inner ear of fish are not the same across species. Further functional studies of the novel proteins we identified during otolith development are required. PMID:26559654

  20. Morphometry of fish inner ear otoliths after development at 3g hypergravity.

    Science.gov (United States)

    Anken, R H; Kappel, T; Rahmann, H

    1998-07-01

    Size and asymmetry (size difference between the left and right sides) of inner ear otoliths of larval cichlid fish were determined after a long-term stay in moderate hypergravity conditions (3g; centrifuge), in the course of which the animals completed their ontogenetic development from hatch to freely swimming. Neither the normal morphogenetic development nor the timely onset and gain of performance of swimming behaviour were impaired by the experimental conditions. However, both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure compared to 1g control specimens raised in parallel. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry of lapilli was pronouncedly decreased compared with the 1g controls. These findings suggest that growth and development of bilateral asymmetry of otoliths are guided by the environmental gravity vector. Some of the hyper-g animals revealed a kinetotic behaviour on transfer to normal 1g earth conditions, which was similar to the behaviour observed in previous experiments on the transfer from 1g to microgravity (parabolic aircraft flights). The lapillar asymmetry of kinetotic samples was found to be significantly higher than that of normally behaving experimental specimens. No differences in asymmetry of sagittae were obtained between the two groups. This supports an earlier theoretical concept, according to which human static space sickness might be based on asymmetric utricular otoliths. PMID:9726679

  1. Fish otoliths from the Paleocene of Denmark

    Directory of Open Access Journals (Sweden)

    Schwarzhans, Werner

    2003-09-01

    Full Text Available Fish otoliths are described from the Lower Paleocene (Danian and Middle Paleocene (Selandian from Sjælland in Denmark. A total of 44 species are described, 23 as newly established and nine in open nomenclature. Thirteen species (including seven new species have been obtained from the Danian poorly consolidated coral limestone at Fakse and 39 species (including 19 new species from the Selandian at localities near Copenhagen.Both stages have previously been poorly known for otoliths in the North Sea Basin, and are described from only two previous publications, i.e. Koken in 1885 from the Selandian of Copenhagen and Roedel in 1930 who described otoliths from erratic ice age boulders in north-east Germany. The original material of both workers has been revised in this bulletin.Otoliths are well known elsewhere in the North Sea Basin since Upper Paleocene (Thanetian times and are described from the London Basin and from Belgium. Palaeographic, palaeoecological and biostratigraphic implications of the otolith findings in the Paleocene of the North Sea Basin are discussed.Two new genera and 23 new species are introduced and described. The new taxa are: Genartina hauniensis n. sp., genus Anguillidarum semisphaeroides n. sp., Conger illaesus n. sp., Rhechias angulosus n. sp., genus Clupeidarum rectiventralis n. sp., genus Salmonidarum acutirostratus n. sp., Protargentinolithus procerus n. sp., Argentina longistrostris n. sp., Aulopus tortus n. sp., genus Myctophidarum schnetleri n. sp., genus ?Percopsiformorum enigmaticus n. sp., Palaeogadus sinangulatus n. sp., Molvia palaeomorpha n. sp., Protocolliolus amorphous n. sp., Coryphaenoides amager n. sp., Hymenocephalus rosenkrantzi n. sp., genus Bythitidarm rasmussenae n. sp., genus Veliferidarum harderi n. sp., genus Zeiformorum janni n. sp., Centroberyx fragilis n. sp., Scorpaena corallophilus n. sp., genus Gempylidarum merus n. sp. and Ostracion pergravis n. sp.

  2. Otolith atlas of fish of the Sinos River.

    Science.gov (United States)

    Bremm, C Q; Schulz, U H

    2014-05-01

    Otoliths are calcium carbonate structures located in the inner ear of fish; they are responsible for hearing and balance. The inner ear has three pairs of otoliths: the lapilli, the sagittae and the asterisci. The sagittae otoliths are the largest and their format is species-specific. Because of their composition, otoliths can resist to the digestive tract of ichthyophagous species, and they can be used as an important tool for identifying species of fish found in stomach contents. The purpose of this work is to provide a photographic guide of the sagittae otoliths of the main fish species from the Sinos River. This atlas consists of photographs of the sagittae otoliths of 36 species belonging to 15 families distributed in five orders. PMID:25166311

  3. Otolith-Canal Convergence In Vestibular Nuclei Neurons

    Science.gov (United States)

    Dickman, J. David; Si, Xiao-Hong

    2002-01-01

    The current final report covers the period from June 1, 1999 to May 31, 2002. The primary objective of the investigation was to determine how information regarding head movements and head position relative to gravity is received and processed by central vestibular nuclei neurons in the brainstem. Specialized receptors in the vestibular labyrinths of the inner ear function to detect angular and linear accelerations of the head, with receptors located in the semicircular canals transducing rotational head movements and receptors located in the otolith organs transducing changes in head position relative to gravity or linear accelerations of the head. The information from these different receptors is then transmitted to central vestibular nuclei neurons which process the input signals, then project the appropriate output information to the eye, head, and body musculature motor neurons to control compensatory reflexes. Although a number of studies have reported on the responsiveness of vestibular nuclei neurons, it has not yet been possible to determine precisely how these cells combine the information from the different angular and linear acceleration receptors into a correct neural output signal. In the present project, rotational and linear motion stimuli were separately delivered while recording responses from vestibular nuclei neurons that were characterized according to direct input from the labyrinth and eye movement sensitivity. Responses from neurons receiving convergent input from the semicircular canals and otolith organs were quantified and compared to non-convergent neurons.

  4. Fish otoliths analysis by PIXE: application to stock discrimination

    International Nuclear Information System (INIS)

    Fish otoliths are continuously deposited from fish birth to its death along with encoding environmental information. In order to decode the information, PIXE was adopted as trace elemental analysis of the otoliths. Strontium to calcium concentration ratios of red sea bream otoliths varied among rearing stations. The Sr/Ca ratios of Lake Biwa catfishes also varied between male and female and among fishing grounds. The PIXE analysis was applied to the fish stock discrimination. (author)

  5. Fish otoliths analysis by PIXE: application to stock discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Nobuaki; Takai, Noriyuki; Sakamoto, Wataru [Kyoto Univ. (Japan). Faculty of Agriculture; Yoshida, Koji; Maeda, Kuniko

    1996-12-31

    Fish otoliths are continuously deposited from fish birth to its death along with encoding environmental information. In order to decode the information, PIXE was adopted as trace elemental analysis of the otoliths. Strontium to calcium concentration ratios of red sea bream otoliths varied among rearing stations. The Sr/Ca ratios of Lake Biwa catfishes also varied between male and female and among fishing grounds. The PIXE analysis was applied to the fish stock discrimination. (author)

  6. Argon laser irradiation of the otolithic organ

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, T.; Nomura, Y.; Young, Y.H.; Hara, M. (Univ. of Tokyo (Japan))

    1990-12-01

    An argon laser was used to irradiate the otolithic organs of guinea pigs and cynomolgus monkeys. After stapedectomy, the argon laser (1.5 W x 0.5 sec/shot) irradiated the utricle or saccule without touching the sensory organs. The stapes was replaced over the oval window after irradiation. The animals used for acute observation were killed immediately for morphologic studies; those used for long-term observation were kept alive for 2, 4, or 10 weeks. Acute observation revealed that sensory and supporting cells were elevated from the basement membrane only in the irradiated area. No rupture of the membranous labyrinth was observed. Long-term observation revealed that the otolith of the macula utriculi had disappeared in 2-week specimens. The entire macula utricili had disappeared in 10-week specimens. No morphologic changes were observed in cochlea, semicircular canals, or membranous labyrinth. The saccule showed similar changes.

  7. Functional asymmetry estimated by measurements of otolith in fish.

    Science.gov (United States)

    Takabayashi, Akira; Ohmura-Iwasaki, Terue

    2003-12-01

    It is widely accepted that the incidence of space adaptation syndrome (SAS) is due to a mismatch of sensory information from various receptors to the central nervous system. We investigated the functional asymmetry of vestibular organ, which may caused sensory conflict in space, by measuring the weight difference of otolith between left and right side in goldfish and carp. In the goldfish utricular otolith, the maximum difference was 0.8 mg and the mean difference was 0.091 mg. The percentage of weight difference to the heavier otolith was calculated. The maximum difference was 20.57% and the mean was 3.035%. A difference exceeding 10% was found in only 2 goldfish. In the carp utricular otolith, the maximum percentage difference of weight was 24.8% and the mean was 3.491%. A difference exceeding 10% was found in only 3 carp. The maximum difference of saccular otolith was 11.8% with the mean of 6.92%, and that of lagenar otolith was 32% with the mean of 5.6% in goldfish. The close relationship of utricular otolith weight between both sides suggested that the otolith asymmetry might not be the main factor inducing SAS at least in goldfish and carp. PMID:15136751

  8. Temperature measurements from oxygen isotope ratios of fish otoliths.

    Science.gov (United States)

    Devereux, I

    1967-03-31

    Measurements have shown that the temperature of a fish's habitat can be deduced from the Oxygen isotope ratio of its otoliths (ear bones). Isotope ratios Obtained from fossil otoliths indicate a water temperature which agrees wiht that found by isotope measurements on associated benthonic foraminifera. PMID:6020293

  9. Evaluation of Response Patterns in Somatic and Otolith Features of Laboratory- Reared and Wild Clarias gariepinus Exposed to Industrial Effluent

    Directory of Open Access Journals (Sweden)

    Aina O. Adeogun

    2013-01-01

    Full Text Available This study was aimed at comparing the responses of somatic and otolith features in Clarias gariepinus under chronic exposure conditions to industrial effluents in the laboratory for 60 days and in the wild for 6 months. Fish were collected upstream and downstream bi-monthly from a river receiving composite mixtures of industrial effluent while laboratory-rearedC. gariepinus were exposed to the same effluent mixtures in 60 days static renewal/bioassay using concentrations of 6.11, 3.05 and 2.23%, respectively and control series. A total of 21 variables representing saggital otolith and somatic data from both wild and laboratory fish were subjected to factor analysis. For laboratory reared fish, PC 1 indexed as ‘otolith factor’, PC 2 indexed as ‘condition factor’ and PC 3 indexed as ‘paired fin factor’ accounted for 26.15, 19.01 and 12.55% of the total variance, respectively. For wild fish, otolith factor (PC 1 and condition factor (PC 2 accounted for 38.24 and 22.69% of the variance respectively. The first 3 components and the first 2 components for laboratory and wild fish accounted for more than 50% of total variance in data. Reliability index (Cronbach’s alpha (&alpha>0.70 showed that the ‘otolith factor’ had strong internal consistency and is reliable as a primary and viable index of stress for both laboratory and wild fish. The complementary role of condition factor in stress detection was also highlighted. The emergence of paired features (otolith, pectoral and pelvic fins as sensitive parameters in toxicity responses may be an indication of the onset of asymmetry in these structures.

  10. A review of image-based tools for automatic fish ageing from otolith features

    OpenAIRE

    Carbini, Sebastien; Chessel, Anatole; Benzinou, Abdesslam; Fablet, Ronan; Mahe, Kelig; De Pontual, Helene

    2008-01-01

    Most of European fish stocks are assessed using age-based models, and otolith interpretation for age estimations costs several million euros annually. In this context, automated ageing systems would provide a mean to 1) standardize ageing, 2) control ageing consistency within and between ageing laboratories 3) build interpreted image data bases ensuring the information conservation and sharing and 4) improve growth studies while reducing the cost of the acquisition of age data. This paper pre...

  11. Aberrant otoliths in juvenile flounder Platichthys flesus (L.

    Directory of Open Access Journals (Sweden)

    Vanessa Neves

    2015-11-01

    Full Text Available Anomalous otolith formation has been reported in freshwater and marine fish species. The prevailing anomaly is the deposition of vaterite instead of aragonite, resulting in different otolith shape and transparency. In this study we report high occurrence rates of anomalous otoliths in juvenile flounder collected in the river Minho estuary (NW Portugal. Several pairs of otoliths were randomly selected from juvenile fish collected between 2013 and 2015, in two estuarine areas, and visually inspected on both sides for the presence of anomalies. Most anomalies consisted of depressions, projections or holes in different parts of the otolith. Distribution of irregularities was examined in relation to site of collection and fish total length. At the site with higher salinity, most otolith pairs were normal. In contrast, at the tidal freshwater station, 43% of the pairs examined were abnormal. In general, both otoliths were affected but the left one presented more extreme changes. The occurrence of anomalies seems to be related to fish size since these were only found in fish smaller than 7.5 cm. Preliminary morphometric analyses indicate that abnormal otoliths have the same proportions as normal ones, but the former seem heavier, for the same sized fish. It is presently unclear how these anomalies affect fish growth or survival. Raman microspectroscopy was used to determine the mineral phases (i.e. type of CaCO3 polymorph in one normal and one abnormal otolith, revealing crystals of aragonitic-type in both cases. SEM-EDS analysis corroborated Raman results and did not reveal differences in chemical composition between abnormal and normal zones but further studies are needed.

  12. PIXE analysis of otoliths from several species of teleost fish

    International Nuclear Information System (INIS)

    In-air PIXE was used to analyze trace elements in otoliths from several species of teleost fish in order to examine the correlation between the trace elements concentrations and environmental conditions. Mn, Fe, Zn and Sr were detected accurately in the order of ppm by using the in-air PIXE. It seemed that concentrations of Sr and Zn in red sea bream otoliths increased in proportion to higher seawater temperature. In addition, there were significant differences in trace element composition between that of reared red sea bream and rockfish and that of wild ones. Preliminary results indicate that the PIXE is a powerful technique to investigate fish otoliths. (author)

  13. PIXE analysis of otoliths from several species of teleost fish

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Nobuaki; Sakamoto, Wataru [Kyoto Univ. (Japan). Faculty of Agriculture; Maeda, Kuniko

    1994-12-31

    In-air PIXE was used to analyze trace elements in otoliths from several species of teleost fish in order to examine the correlation between the trace elements concentrations and environmental conditions. Mn, Fe, Zn and Sr were detected accurately in the order of ppm by using the in-air PIXE. It seemed that concentrations of Sr and Zn in red sea bream otoliths increased in proportion to higher seawater temperature. In addition, there were significant differences in trace element composition between that of reared red sea bream and rockfish and that of wild ones. Preliminary results indicate that the PIXE is a powerful technique to investigate fish otoliths. (author).

  14. Models of the mechanical sensitivity and growth of otoliths in fish.

    Science.gov (United States)

    Kondrachuk, Alexander V

    2003-01-01

    It has been suggested that, in the fish, the change of otolith mass during development under altered gravity conditions and the growth of otoliths in normal conditions, are determined by feedback between otolith dynamics and the processes that regulate otolith growth. The hypothesis originates from an oscillator model of the otolith in which otolith mass is one of the parameters. However, the validity of this hypothesis is not obvious and has not been experimentally verified. We tested this hypothesis by comparing the oscillator model with a simplified spatially distributed model of the otolith. It was shown that in the case of a spatially distributed fixation of the otolith plate (otoconial layer) to the macular surface, the mechanical sensitivity of the otolith does not depend on the total otolith mass nor on its longitudinal size. It is determined by otolith thickness, the Young's modulus and viscosity of gel layer of the growing otolith. These parameters may change in order to maintain otolith sensitivity under conditions (such as growth or altered gravity) that change the dynamics of otolith movement. PMID:15096663

  15. The role of otolith size in hearing – Insights from cichlid fishes

    Directory of Open Access Journals (Sweden)

    Tanja Schulz-Mirbach

    2015-10-01

    Full Text Available Otolithic end organs in fishes function as accelerometers and are involved in the senses of balance and hearing (e.g. Popper et al. 2005. Otolith mass and shape are likely decisive factors influencing otolith motion, but while it is largely unknown how different shapes affect otolith movement relative to the sensory epithelium (Popper et al. 2005, greater otolith mass is predicted to result in enhanced stimulation of sensory hair cells and improved hearing (Lychakov and Rebane 2005. What few studies exist on this topic, however, yielded contradicting results in that they did or did not find a correlation between increased otolith mass and enhanced hearing (see Kéver et al. 2014. We investigated the relationship between otolith morphology (including 3D-models of otoliths based on high-resolution microCT imaging and otolith weight and hearing abilities in cichlids while comparing three species (Etroplus maculatus, Hemichromis guttatus, Steatocranus tinanti with different swimbladder morphology and hearing abilities (Schulz-Mirbach et al. 2014. We predicted Etroplus maculatus—the species that displays the best hearing sensitivities—to possess larger/heavier otoliths. As swimbladder extensions in this species are connected to the lagena, we further predicted to find heavier lagenar otoliths. Compared to H. guttatus and S. tinanti, E. maculatus showed the heaviest saccular otoliths, while lagenar otoliths were significantly thinner and lighter than in the former two species, apparently contradicting the hypothesis that the lagena and its otolith are primarily involved in improved hearing abilities. Our results support the idea that there is no ‘simple’ relationship between otolith weight, ancilliary auditory structures and hearing abilities. 3D-models of inner ears and otoliths may be ideally suited for future studies modeling complex otolith motion and thus, may provide a better understanding of how otolith morphology contributes to inner

  16. Validation of daily increment formation in otoliths for Gymnocypris selincuoensis in the Tibetan Plateau, China.

    Science.gov (United States)

    Ding, Chengzhi; Chen, Yifeng; He, Dekui; Tao, Juan

    2015-08-01

    Daily increment validation in fish otolith is fundamental to studies on fish otolith microstructure, age determination and life history traits, and thus is critical for species conservation and fishery management. However, it has never been done for Schizothoracine fish, which is the dominant component of fish fauna in the Tibetan Plateau. This study validated the daily increment formation of Gymnocypris selincuoensis, as a representative of Schizothoracine fish, by monitoring the growth of hatchery-reared larvae group and wild-caught post-yolk-sac larvae group under controlled experiments. The results from monitoring the hatchery-reared larvae group showed that sagittae and lapilli were found in yolk-sac larvae, and formed 5-7 days before hatching, but asterisci were not found until 11 days post-hatching. The first increment in sagittae and lapilli was formed in the first day after hatching. The daily periodicity of increment formation was examined and confirmed in sagittae and lapilli of both larvae groups. However, sagittae were better for age determination than lapilli for larvae at earlier days. For larval G. selincuoensis older than 50 days, lapilli were the only otolith pair suitable for larvae daily age determination. This study validated the daily increment formation in Schizothoracine fish for the first time has primary implications to other fishes from this subfamily. PMID:26380660

  17. Trace metals and otolith defects in mocha mice.

    Science.gov (United States)

    Rolfsen, R M; Erway, L C

    1984-01-01

    Mocha mice with pigment anomalies of the coat, eyes, and inner ears also have congenital otolith defects, and they exhibit progressive cochlear degeneration. Mocha mice were first reported to exhibit otolith defects comparable to those of pallid mice. Since manganese supplementation is effective in preventing the otolith defects in pallid mice and in pastel mink, we sought to establish whether or not manganese also might be effective in mocha mice. The otolith defects of mocha mice were prevented or reduced by supplementing the pregnant dams with manganese and/or zinc. The mocha mice also exhibited high perinatal mortality that was not reduced by the supplementary metals. Surviving mocha mice have behavioral anomalies associated with their inner ear defects. Preliminary observations of auditory-evoked brainstem responses and of cochlear degeneration in the mocha mice are discussed. PMID:6736600

  18. Shedding light on fish otolith biomineralization using a bioenergetic approach.

    Directory of Open Access Journals (Sweden)

    Ronan Fablet

    Full Text Available Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on biomineralization. This model resolves controversial issues and explains poorly understood observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves.

  19. Lead-Radium Activity Ratios From Otoliths of Regional Bottomfishes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains lead-radium dating of opakapaka (Pristipomoides filamentosus) otoliths from recent and archival collections (1987-2009).

  20. Shedding light on fish otolith biomineralization using a bioenergetic approach.

    Science.gov (United States)

    Fablet, Ronan; Pecquerie, Laure; de Pontual, Hélène; Høie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A L M

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on biomineralization. This model resolves controversial issues and explains poorly understood observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves. PMID:22110601

  1. Bio-PIXE marine science. Otoliths and plankton

    International Nuclear Information System (INIS)

    Otoliths and phytoplanktons have been investigated using a nuclear microprobe. A brief description of sample preparation and irradiation conditions is given. The results indicate a great potential of the technique in marine sciences. (author)

  2. Suitability of otolith microchemistry for stock separation of Baltic cod

    DEFF Research Database (Denmark)

    Heidemann, F; Marohn, L; Hinrichsen, HH; Huwer, B; Hüssy, K; Klügel, A; Böttcher, U; Hanel, R

    2012-01-01

    Microchemical otolith analyses have been shown to provide valuable information on the life history, dispersal and stock characteristics of teleost fish. In the present study, the suitability of this technique for identifying the origin and distribution of Atlantic cod Gadus morhua L. from the...... Baltic Sea was examined using laser ablation-ICPMS. The capacity to distinguish individuals from different Baltic Sea stocks and from the adjacent North Sea stock based on incoporation of stock-specific elemental fingerprints along otolith growth axes was investigated. It was further tested if different...... origins led to spawning-site specific element concentrations in otolith cores. The results indicate that microchemical analyses of Baltic cod otoliths are applicable for differentiating individuals of different stocks. Analyses of similarities including 12 element/calcium ratios resulted in significant...

  3. Modification of Otolith Reflex Asymmetries Following Space Flight

    Science.gov (United States)

    Clarke, Andrew H.; Schoenfeld, Uwe; Wood, Scott J.

    2011-01-01

    We hypothesize that changes in otolith-mediated reflexes adapted for microgravity contribute to perceptual, gaze and postural disturbances upon return to Earth s gravity. Our goal was to determine pre- versus post-fight differences in unilateral otolith reflexes that reflect these adaptive changes. This study represents the first comprehensive examination of unilateral otolith function following space flight. Ten astronauts participated in unilateral otolith function tests three times pre-flight and up to four times after Shuttle flights from landing day through the subsequent 10 days. During unilateral centrifugation (UC, +/- 3.5cm at 400deg/s), utricular function was examined by the perceptual changes reflected by the subjective visual vertical (SVV) and by video-oculographic measurement of the otolith-mediated ocular counter-roll (OOR). Unilateral saccular reflexes were recorded by measurement of collic Vestibular Evoked Myogenic Potential (cVEMP). Although data from a few subjects were not obtained early post-flight, a general increase in asymmetry of otolith responses was observed on landing day relative to pre-flight baseline, with a subsequent reversal in asymmetry within 2-3 days. Recovery to baseline levels was achieved within 10 days. This fluctuation in the asymmetry measures appeared strongest for SVV, in a consistent direction for OOR, and in an opposite direction for cVEMP. These results are consistent with our hypothesis that space flight results in adaptive changes in central nervous system processing of otolith input. Adaptation to microgravity may reveal asymmetries in otolith function upon to return to Earth that were not detected prior to the flight due to compensatory mechanisms.

  4. Alizarin marking of whitefish, Coregonus lavaretus otoliths during egg incubation

    OpenAIRE

    Eckmann, Reiner

    2003-01-01

    Alizarin red S from 200 to 5000 mg L-1 was used to mark the otoliths of whitefish embryos Coregonus lavaretus (L.) from 5 days after fertilization until shortly before hatching, to develop a method for evaluating the effect of stocking whitefish. Mark quality depended on developmental stage at the time of immersion. The best results were obtained when the otolith primordia had formed and had started aggregating to form the innermost part of the nucleus. This was verified by in vitro staining ...

  5. Pleistocene fish otoliths from the Mediterranean Basin: a synthesis

    OpenAIRE

    Girone, A.; Nolf, D.; Cappetta, H

    2006-01-01

    An overview of upper pPliocene and Pleistocene otolith assemblages is compiled on the basis of both literature data and newly collected material from several sections located mainly in southern Italy. One hundred and five taxa are listed. Additional comments are provided for taxa subject to discussion. The composition and affinities of the Mediterranean Pleistocene otolith associations (consisting mainly of deep sea fishes) is checked against the available data for Pre-Messinian, Pliocene, an...

  6. Shedding light on fish otolith biomineralization using a bioenergetic approach

    DEFF Research Database (Denmark)

    Fablet, R.; Pecquerie, L.; de Pontual, H.;

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosys...... simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves...

  7. Effect of long-term microgravity on the mineralisation of inner ear otoliths of fish - a spaceflight study

    Science.gov (United States)

    Anken, Ralf

    The "heavy bodies" (i.e., statoliths or otoliths, mainly made up of calcium carbonate and protein) in the inner ears of vertebrates transform the physical parameter "gravity" to biological signals needed for postural control. It has been shown earlier that hypergravity slows down inner ear otolith growth in developing fish (via a down-regulation of carbonic anhydrase reactivity) as an adaptation towards altered environmental gravity. We were thus prompted to elucidate whether long-term microgravity would possibly yield opposite effects. Therefore, larval siblings of cichlid fish (Oreochromis mossambicus) were housed in a bioregenerative life support system (OMEGAHAB) using green algae (Euglena gracilis) for oxygen supply. The experiment was successfully flown on the FOTON M-3 mission. Prior to launch, otoliths were stained with a fluorescent calcium tracer (Alizarin Complexone). This treatment both allowed an assessment of otolith growth (size) after recovery as well as an analysis of relocations of calcium deposits. Calcium and strontium contents were determined using inductively coupled plasma mass spectrometry. The results will be communicated at the meeting. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 0527).

  8. Effect of acetazolamide on the otolith growth of goldfish

    International Nuclear Information System (INIS)

    In order to clarify the involvement of a functional carbonic anhydrase (CA) system in the otolith formation of the goldfish, Carassius auratus, acetazolamide, a specific CA inhibitor, was injected intraperitoneally every 3 or 4 days, and its inhibitory effect on the otolith growth was examined by means of a tetracycline labelling technique. Calcium-45 deposition on the otolith was also examined after a single injection of the drug. Given in multiple doses of 50 mg per Kg of body weight, acetazolamide did not reduce the growth rate of the otolith on either dorsal or ventral side. With multiple doses of 100 mg, however, the dorsal growth was significantly depressed by 17%. The ventral growth was not affected. Similarly, calcium-45 deposition on the otolith was effectively reduced (39%) only when a dose of 100 mg was given. These results suggest that, if involved, the enzyme-catalyzed hydration or hydroxylation of CO2 is not indispensable to the carbonate formation of the otolith. (auth.)

  9. Strontium randomly substituting for calcium in fish otolith aragonite.

    Science.gov (United States)

    Doubleday, Zoë A; Harris, Hugh H; Izzo, Christopher; Gillanders, Bronwyn M

    2014-01-01

    The chemistry of fish ear bones (otoliths) is used to address fundamental questions in fish ecology and fisheries science. It is assumed that strontium (Sr), the most important element used in otolith chemistry research, is bound within the aragonitic calcium carbonate lattice of otoliths via random chemical replacement of calcium; however, this has never been tested and three other alternatives exist with regard to how Sr may be incorporated. If any variation in the mode of incorporation occurs, otolith chemistry data may be misinterpreted, impacting how fish and fisheries are understood and managed. Using X-ray absorption spectroscopy (specifically, analysis of extended X-ray absorption fine structure or EXAFS), we investigated how Sr is incorporated within fish otoliths from seven species collected from a range of aquatic environments. For comparison, aragonitic structures from other aquatic taxa (cephalopods and coral) were also analyzed. The results consistently indicated for all samples that Sr randomly replaces Ca within the aragonite lattice. This research explicitly shows how Sr is bound within otoliths and validates a fundamental and long-held assumption in aquatic research. PMID:24299165

  10. Investigating global change and fish biology with fish otolith radiocarbon

    Science.gov (United States)

    Kalish, John M.

    1994-06-01

    Fish otoliths, calcium carbonate gravity and auditory receptors in the membranous labyrinths of teleost fish, can provide radiocarbon data that are valuable to a wide range of disciplines. For example, the first pre- and post-bomb time series of radiocarbon levels from northern or southern hemisphere temperate oceans was obtained by carrying out accelerator mass spectrometry analyses on selected regions of fish otoliths. These data can provide powerful constraints on both carbon cycle models and ocean general circulation models. Because fish otoliths can serve as a proxy of radiocarbon in seawater dissolved inorganic carbon in all oceans and at most depths, there is considerable scope for further investigations of otolith radiocarbon in relation to both oceanography and global change. In addition to applications relevant to global change, fish otoliths are also valuable sources of information on the age, growth, and ecology of fishes, with age being among the most important parameters in population modelling and fisheries management. Use of the bomb radiocarbon chronometer to validate fish age determination methods offers considerable advantages over traditional forms of age validation and promises to become a standard tool in fish biology and fisheries management. Radiocarbon data from otoliths can also provide valuable information on the ecology of fishes and has already provided surprising information relevant to the ecology of some deep-sea fishes.

  11. Fish otolith contains a unique structural protein, otolin-1.

    Science.gov (United States)

    Murayama, Emi; Takagi, Yasuaki; Ohira, Tsuyoshi; Davis, James G; Greene, Mark I; Nagasawa, Hiromichi

    2002-01-01

    A collagen-like protein was identified from the otoliths of the chum salmon, Oncorhynchus keta. The otolith, composed mainly of calcium carbonate with small amount of organic matrices, is formed in the inner ear and serves as a part of the hearing and balance systems. Although the organic matrices may play important roles in the growth of otolith, little is known about their chemical nature and physiological function. In this study, a major organic component of the otolith, designated otolin-1, which may serve as a template for calcification, was purified. The sequences of two tryptic peptides from otolin-1 revealed high homology with parts of a saccular collagen which had been described previously [Davis, J.G., Oberholtzer, J.C., Burns, F.R. & Greene, M.I. (1995) Science 267, 1031-1034]. Cloning of a cDNA coding for otolin-1 revealed that the deduced amino-acid sequence contained a collagenous domain in the central part of the protein. Although collagen is the most abundant structural protein in the animal body, otolin-1 mRNA was expressed specifically in the sacculus. Immunohistochemical studies showed that otolin-1 is synthesized in the transitional epithelium and transferred to the otolith and otolithic membrane. This is the first report concerning characterization of a structural protein containing many tandem repeats of the sequence, Gly-Xaa-Yaa, typical for collagen from the biomineral composed of calcium carbonate. PMID:11856329

  12. ARE ELEMENTAL FINGERPRINTS OF FISH OTOLITHS DISTINCT AMONG GREAT LAKES COASTAL NURSERY AREAS?

    Science.gov (United States)

    Elemental composition of an otolith reflects a fish's rearing environment, so otolith geochemistry can record differences in ambient water conditions specific to habitats used during a fish's life history. Although few studies have been conducted in freshwater, trace ...

  13. Investigation of fish otoliths by combined ion beam analysis

    International Nuclear Information System (INIS)

    Complete text of publication follows. This work was implemented within the framework of the Hungarian Ion beam Physics Platform (http://hipp.atomki.hu/). Otoliths are small structures, 'the ear stones' of a fish, and are used to detect acceleration and orientation. They are composed of a combination of protein matrix and calcium carbonate (CaCO3) forming aragonite micro crystals. They have an annually deposited layered conformation with a microstructure corresponding to the seasonal and daily increments. Trace elements, such as Sr, Zn, Fe etc., are also incorporated into the otolith from the environment and the nutrition. The elemental distribution of the otolith of fresh water fish burbot (Lota lota L.) collected in Hungary was measured with Elastic Recoil Detection Analysis (ERDA), Rutherford backscattering spectrometry (RBS) and Particle Induced X-ray Emission (PIXE) at the Nuclear Microprobe Facility of HAS ATOMKI. The spatial 3D structure of the otolith could be observed with a sub-micrometer resolution. It is confirmed that the aragonite micro-crystals are covered by an organic layer and there are some protein rich regions in the otolith, too. By applying the RBSMAST code developed for RBS on macroscopic structure, it was proven that the orientation of the needle shaped aragonite crystals is considerably different at adjacent locations in the otolith. The organic and inorganic component of the otolith could be set apart in the depth selective hydrogen and calcium maps derived by micro- ERDA and micro-RBS. Similar structural analysis could be done near the surface by combining the C, O and Ca elemental maps determined by micro-PIXE measurements. It was observed that the trace metal Zn is bound to the protein component. Acknowledgements This work was partially supported by the Hungarian OTKA Grant No. T046238 and the EU cofunded Economic Competitiveness Operative Programme (GVOP-3.2.1.-2004-04-0402/3.0)

  14. Metal contents in tench otoliths: relationships to the aquatic environment.

    Science.gov (United States)

    Adami, G; Miletić, M; Siviero, P; Barbieri, P; Reisenhofer, E

    2001-01-01

    A monitoring of the quality of waters was attempted determining metal accumulation in target organs as otoliths of freshwater fish. Tenchs of age ranging between 2 and 10 years were sampled in three different canals receiving wastewater from industrial, agricultural and urban activities. Metal contents were determined in both lapilli and asterisci otoliths, using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Analytical data are reported for minor metals and for some trace metals. Al, Fe and Zn have contents depending on the environment where the fish has lived, while Na, K, Ca and Sr contents are insensitive to the different aquatic habitat. Considering the two types of otolith separately, lapilli display a different affinity for trace metals (Al, Fe and Zn), while in asterisci this affinity is matched only for zinc. The high affinity of zinc for both types of otoliths suggests using this metal for discriminating the fresh waters by checking its accumulation in otoliths, as well as correlating this accumulation with age of the fish: a negative power curve equation is proposed. Since highest concentrations are found in individuals of 2-3 yr., it is advisable to use this fish for such environmental studies. PMID:11554178

  15. Optical manipulation for optogenetics: otoliths manipulation in zebrafish (Conference Presentation)

    Science.gov (United States)

    Favre-Bulle, Itia A.; Scott, Ethan; Rubinsztein-Dunlop, Halina

    2016-03-01

    Otoliths play an important role in Zebrafish in terms of hearing and sense of balance. Many studies have been conducted to understand its structure and function, however the encoding of its movement in the brain remains unknown. Here we developed a noninvasive system capable of manipulating the otolith using optical trapping while we image its behavioral response and brain activity. We'll also present our tools for behavioral response detection and brain activity mapping. Acceleration is sensed through movements of the otoliths in the inner ear. Because experimental manipulations involve movements, electrophysiology and fluorescence microscopy are difficult. As a result, the neural codes underlying acceleration sensation are poorly understood. We have developed a technique for optically trapping otoliths, allowing us to simulate acceleration in stationary larval zebrafish. By applying forces to the otoliths, we can elicit behavioral responses consistent with compensation for perceived acceleration. Since the animal is stationary, we can use calcium imaging in these animals' brains to identify the functional circuits responsible for mediating responses to acceleration in natural settings.

  16. Bisphenol A induces otolith malformations during vertebrate embryogenesis

    Directory of Open Access Journals (Sweden)

    Demeneix Barbara

    2011-01-01

    Full Text Available Abstract Background The plastic monomer and plasticizer bisphenol A (BPA, used for manufacturing polycarbonate plastic and epoxy resins, is produced at over 2.5 million metric tons per year. Concerns have been raised that BPA acts as an endocrine disruptor on both developmental and reproductive processes and a large body of evidence suggests that BPA interferes with estrogen and thyroid hormone signaling. Here, we investigated BPA effects during embryonic development using the zebrafish and Xenopus models. Results We report that BPA exposure leads to severe malformations of the otic vesicle. In zebrafish and in Xenopus embryos, exposure to BPA during the first developmental day resulted in dose-dependent defects in otolith formation. Defects included aggregation, multiplication and occasionally failure to form otoliths. As no effects on otolith development were seen with exposure to micromolar concentrations of thyroid hormone, 17-ß-estradiol or of the estrogen receptor antagonist ICI 182,780 we conclude that the effects of BPA are independent of estrogen receptors or thyroid-hormone receptors. Na+/K+ ATPases are crucial for otolith formation in zebrafish. Pharmacological inhibition of the major Na+/K+ ATPase with ouabain can rescue the BPA-induced otolith phenotype. Conclusions The data suggest that the spectrum of BPA action is wider than previously expected and argue for a systematic survey of the developmental effects of this endocrine disruptor.

  17. Fish otoliths: do sizes correlate with taxonomic group, habitat and/or luminescence?

    Science.gov (United States)

    Paxton, J R

    2000-09-29

    Otoliths are dense structures in the ears of fishes that function in hearing and gravity perception. Otolith (sagitta) diameters, as percentages of standard length (% SL), are calculated for 247 marine fish species in 147 families and compared by taxonomic group (usually order), habitat and presence or absence of luminescence. Otolith sizes range from 0.4-31.4 mm and 0.08-11.2% SL. The eel and spiny eel orders Anguilliformes and Notacanthiformes have small to very small otoliths, as do the triggerfish order Tetraodontiformes, pipefish order Gasterosteiformes, billfish suborder Scombroidei and many of the dragonfish order Stomiiformes. The soldierfish order Beryciformes has moderate to very large otoliths. The perch order Perciformes has a wide range of otolith sizes but most have small to moderate otoliths 2-5% SL. Only 16 out of the 247 species have the relatively largest otoliths, over 7% SL. Seven out of these 16 species are also luminous from a variety of habitats. Luminous species have slightly to much larger otoliths than non-luminous species in the same family Both beryciforms and luminous fishes live in low-light environments, where acute colour vision is probably impossible. Most fishes of the epipelagic surface waters have very small otoliths, perhaps due to background noise and/or excessive movement of heavy otoliths in rough seas. Bathypelagic species usually have small otoliths and regressed or absent swimbladders. Other habitats have species with a range of otolith sizes. While the relationship between hearing ability and otolith length is unknown, at least some groups with modified swim-bladders have larger otoliths, which may be associated with more acute hearing. PMID:11079419

  18. Effects of salinity on trace elements in otoliths of Masu salmon

    International Nuclear Information System (INIS)

    PIXE was adopted for analysis of trace elements in otoliths of Masu salmon Oncorhynchus masou masou to examine relationship between trace elements and environmental salinity. The otoliths were removed from salmon juveniles reared in four values of salinity and wild ones. The otolith Sr concentrations of reared individuals are positively related to salinity and there is significant difference between freshwater and seawater. The otoliths of smolts contain more Sr than those of parrs. It seems that the Sr concentrations in otoliths of Masu salmon reflect salinity where they had stayed and show the migration pattern. (author)

  19. Provenancing fish in freshwaters of the Alpine Foreland using Sr/Ca and 87Sr/86Sr ratios in otoliths and otolith shape parameters

    OpenAIRE

    Johannes Oehm; Johanna Irrgeher

    2015-01-01

    Analysis of elemental and isotopic compositions and of the shape of fish otoliths has become an important tool in fish ecology. Highly relevant questions like origin and migration of fish over their life time cannot be answered easily with other methods. However, before otolith chemistry and shape can be applied for such kind of studies, the relation between the specific environmental conditions and both, the chemistry and shape of otoliths, needs to be understood. Therefore in this study,...

  20. Effect of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops.

    Science.gov (United States)

    Perry, Dean M; Redman, Dylan H; Widman, James C; Meseck, Shannon; King, Andrew; Pereira, Jose J

    2015-09-01

    Increasing amounts of atmospheric carbon dioxide (CO2) from human industrial activities are causing changes in global ocean carbonate chemistry, resulting in a reduction in pH, a process termed "ocean acidification." It is important to determine which species are sensitive to elevated levels of CO2 because of potential impacts to ecosystems, marine resources, biodiversity, food webs, populations, and effects on economies. Previous studies with marine fish have documented that exposure to elevated levels of CO2 caused increased growth and larger otoliths in some species. This study was conducted to determine whether the elevated partial pressure of CO2 (pCO2) would have an effect on growth, otolith (ear bone) condition, survival, or the skeleton of juvenile scup, Stenotomus chrysops, a species that supports both important commercial and recreational fisheries. Elevated levels of pCO2 (1200-2600 μatm) had no statistically significant effect on growth, survival, or otolith condition after 8 weeks of rearing. Field data show that in Long Island Sound, where scup spawn, in situ levels of pCO2 are already at levels ranging from 689 to 1828 μatm due to primary productivity, microbial activity, and anthropogenic inputs. These results demonstrate that ocean acidification is not likely to cause adverse effects on the growth and survivability of every species of marine fish. X-ray analysis of the fish revealed a slightly higher incidence of hyperossification in the vertebrae of a few scup from the highest treatments compared to fish from the control treatments. Our results show that juvenile scup are tolerant to increases in seawater pCO2, possibly due to conditions this species encounters in their naturally variable environment and their well-developed pH control mechanisms. PMID:26442471

  1. Fish age validation by radiometric analysis of otoliths

    International Nuclear Information System (INIS)

    Radiochemical analysis of aragonitic fish otoliths provides a useful approach to validating ages obtained by more common methods. The history of applications of radiometry using short-lived natural isotopes to clams, Nautilus, living corals and fish otoliths is briefly reviewed. The biogeochemical assumptions required for successful use of these techniques are discussed, and the appropriate mathematical treatments required for data analysis are outlined. Novel normalization techniques designed to widen the validity of this approach are proposed. Desirable lines of further research are also briefly discussed. 38 refs., 1 tab

  2. PIXE analysis of fish otoliths. Application to fish stock discrimination

    International Nuclear Information System (INIS)

    PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author)

  3. PIXE analysis of fish otoliths. Application to fish stock discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Nobuaki; Sakamoto, Wataru [Kyoto Univ., Kyoto (Japan). Lab. of Fisheries and Environmental Oceanography; Tateno, Koji; Yoshida, Koji

    1996-12-31

    PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author)

  4. Magnetic resonance imaging of the saccular otolithic mass.

    OpenAIRE

    Sbarbati, A; Leclercq, F; Antonakis, K; Osculati, F.

    1992-01-01

    The frog's inner ear was studied in vivo by high spatial resolution magnetic resonance imaging at 7 Tesla. The vestibule, the internal acoustic meatus, and the auditory tube have been identified. The large otolithic mass contained in the vestibule showed a virtual absence of magnetic resonance signal probably due to its composition of closely packed otoconia.

  5. Otoliths as an integral part in fossil fish taxonomy

    Directory of Open Access Journals (Sweden)

    Christoph Gierl

    2015-11-01

    Full Text Available Otoliths are small structures in the skull of fishes. They are responsible for hearing and orientation in the 3-dimensional space. They also hold valuable information regarding the taxonomy. Their outline, the shape of the sulcus and other features allow the determination of a fish even to the species level. A lot of fossil species are solely based on otoliths because of their good chance of preservation. Gobies are in this case no different. An additional challenge in gobies is their high similarity between species concerning the preservable parts. Fossil skeletons that are 20 Million years old can show only few differences compared to recent gobies. These features are often hardly recognizable due to their preservation. As a consequence many fossil gobies have been assigned to the genus Gobius sensu lato. Examples are two gobies from the Miocene of Southern Germany. They have a unique combination of characters (six branchiostegals, palatine resembling a “T”, no entopterygoid that allows the rectification of a new fossil genus but the two species are hardly distinguishable based only on the skeleton. The key hints in having two species are the otoliths. They show slight but consistent differences in their outline. This shows that otoliths can be a key feature in species identification. They should also be taken into consideration by recent fish species. Not to mention their possible phylogenetic potential that remains to be explored.

  6. Otolith geochemistry does not reflect dispersal history of clownfish larvae

    Science.gov (United States)

    Berumen, M. L.; Walsh, H. J.; Raventos, N.; Planes, S.; Jones, G. P.; Starczak, V.; Thorrold, S. R.

    2010-12-01

    Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: “self-recruiters” spawned by parents on Kimbe Island and “immigrants” that had dispersed from distant reefs (>10 km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags.

  7. Two new methods of determining radon diffusion in fish otoliths

    International Nuclear Information System (INIS)

    Otoliths are bony structures found in the ears of fish and used in the 210Pb/226Ra dating method for age determination. This paper checks the assumption that 222Rn is not lost from or added to orange roughy fish otoliths by diffusion, which would invalidate the technique. The first method of monitoring diffusion relies on measuring the gamma activity of daughter radionuclides. Otoliths were exposed to an atmosphere enriched in 222Rn for 10 days, and the supported gamma activity inside them measured allowing for various decay corrections. The calculated radon addition was (0.5 ±0.5)% of the activity of the 226Ra present. The second method used an alpha spectrometer and attempted to detect 222Rn directly outguessed from otoliths in the detector vacuum chamber. The results were consistent within errors with those of the first method and showed no loss or gain of 222Rn, supporting previous estimates of a long life-span for the orange rough y. In contrast it was found that approximately 10% of 222Rn formed in orange roughy fish scales was lost to an evacuated environment, (hence perhaps to an aqueous environment) and that for this species it could be difficult to base a dating method on analysis of scales. Nevertheless a preliminary minimum age of 57 years was obtained. The methods could be used with non-biological samples to determine 222Rn diffusion rates. (author). 17 refs., 5 figs

  8. Otolith microchemistry of tropical diadromous fishes: spatial and migratory dynamics

    Science.gov (United States)

    Smith, William E.; Kwak, Thomas J.

    2014-01-01

    Otolith microchemistry was applied to quantify migratory variation and the proportion of native Caribbean stream fishes that undergo full or partial marine migration. Strontium and barium water chemistry in four Puerto Rico, U.S.A., rivers was clearly related to a salinity gradient; however, variation in water barium, and thus fish otoliths, was also dependent on river basin. Strontium was the most accurate index of longitudinal migration in tropical diadromous fish otoliths. Among the four species examined, bigmouth sleeper Gobiomorus dormitor, mountain mullet Agonostomus monticola, sirajo goby Sicydium spp. and river goby Awaous banana, most individuals were fully amphidromous, but 9-12% were semi-amphidromous as recruits, having never experienced marine or estuarine conditions in early life stages and showing no evidence of marine elemental signatures in their otolith core. Populations of one species, G. dormitor, may have contained a small contingent of semi-amphidromous adults, migratory individuals that periodically occupied marine or estuarine habitats (4%); however, adult migratory elemental signatures may have been confounded with those related to diet and physiology. These findings indicate the plasticity of migratory strategies of tropical diadromous fishes, which may be more variable than simple categorization might suggest.

  9. Fish otoliths: daily growth layers and periodical patterns.

    Science.gov (United States)

    Panella, G

    1971-09-17

    The early-stage annual rings in otoliths from some cold-temperate fish consist of thin growth bands, the number of which corresponds to that of the days in a year. This indicates that growth takes place by daily increments. Other recurrent patterns show a fortnightly and monthly periodicity. Spawning rings are microscopically distinguishable from winter rings. PMID:5098955

  10. A review on otolith models in human perception.

    Science.gov (United States)

    Asadi, Houshyar; Mohamed, Shady; Lim, Chee Peng; Nahavandi, Saeid

    2016-08-01

    The vestibular system, which consists of semicircular canals and otolith, are the main sensors mammals use to perceive rotational and linear motions. Identifying the most suitable and consistent mathematical model of the vestibular system is important for research related to driving perception. An appropriate vestibular model is essential for implementation of the Motion Cueing Algorithm (MCA) for motion simulation purposes, because the quality of the MCA is directly dependent on the vestibular model used. In this review, the history and development process of otolith models are presented and analyzed. The otolith organs can detect linear acceleration and transmit information about sensed applied specific forces on the human body. The main purpose of this review is to determine the appropriate otolith models that agree with theoretical analyses and experimental results as well as provide reliable estimation for the vestibular system functions. Formulating and selecting the most appropriate mathematical model of the vestibular system is important to ensure successful human perception modelling and simulation when implementing the model into the MCA for motion analysis. PMID:27091675

  11. Otolith geochemistry does not reflect dispersal history of clownfish larvae

    KAUST Repository

    Berumen, Michael L.

    2010-07-01

    Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: "self-recruiters" spawned by parents on Kimbe Island and "immigrants" that had dispersed from distant reefs (>10 km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags. © 2010 Springer-Verlag.

  12. Fish inner ear otolith size and bilateral asymmetry during development.

    Science.gov (United States)

    Anken, R H; Werner, K; Ibsch, M; Rahmann, H

    1998-07-01

    Size and bilateral asymmetry (i.e. size difference between the left and the right hand side) of inner ear otoliths of larval mouthbreeding cichlid fish were determined during the ontogenetic development of larvae from hatching to the free swimming stage. Animals of two batches were raised in aquarium hatch baskets. The basket containing one batch was placed directly above aeration equipment, resulting in random water circulation within the basket, which constantly shifted the specimens around ('shifted' specimens). The second batch of animals was raised in parallel without shifting. Due to the weight of the yolk-sacs, these animals lay on their sides until the yolk-sacs were resorbed ('stationary' specimens). The groups of larvae did not differ from one another in respect of individual general development, nor in otolith size. Contrasting results were obtained regarding bilateral otolith asymmetry: In both shifted and stationary animals, asymmetry of utricular and saccular otoliths (lapilli and sagittae, respectively) ranged at comparatively low values throughout development. However, by comparison with shifted individuals, lapillar asymmetry of stationary animals showed a highly significant increase during early development when larvae were forced to lay on their sides due to their prominent yolk-sacs. In later developmental stages, when they began to swim freely, a dramatic decrease in lapillar asymmetry was apparent. These findings indicate that development of lapillar asymmetry depends on the direction of the acting gravity vector relative to the positioning of the larvae, suggesting that the size (or mass) of a given otolith is regulated via a feedback mechanism. PMID:9682810

  13. Analysis of fish otoliths by electrothermal vaporization inductively coupled plasma mass spectrometry: aspects of precipitating otolith calcium with hydrofluoric acid for trace element determination.

    Science.gov (United States)

    Arslan, Zikri

    2005-03-15

    A method is developed for determination of trace elements, including Ag, As, Cd, Co, Cr, Cu, Mn, Ni, Se, Tl and Zn, in fish otoliths by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS). Hydrofluoric acid was used to precipitate calcium resulting from acid dissolution of otolith calcium carbonate. Initial acidity of the sample solution influenced the precipitation efficiency of calcium fluoride. Up to 99.5% of Ca was precipitated in solutions that contained less than 2% (v/v) HNO(3). Recoveries of the elements obtained from spiked artificial otolith solutions were between 90 and 103%. Stabilization of the elements within the ETV cell was achieved with 0.3mug Pd/0.2mug Rh chemical modifier that also afforded optimum sensitivity for multielement determination. The method was validated by the analysis of a fish otolith reference material (CRM) of emperor snapper, and then applied to the determination of the trace elements in otoliths of several fish species captured in Raritan Bay, New Jersey. Results indicated that fish physiology and biological processes could influence the levels of Cu, Mn, Se and Zn in the otoliths of fish inhabiting a similar aqueous environment. Otolith concentrations of Cr and Ni did not show any significant differences among different species. Concentrations for Ag, As, Cd, Co and Tl were also not significantly different, but were very low indicating low affinity of otolith calcium carbonate to these elements. PMID:18969949

  14. Otoliths as recorders of palaeoenvironments: comparison of radiocarbon age and isoleucine epimerization in Pleistocene golden perch 'Macquaria ambigua' otoliths from Willandra Lakes

    International Nuclear Information System (INIS)

    Fish otoliths form by the accretion of layers of calcium carbonate and organic-rich material that often form distinctive layers over time scales ranging from days to years. These layers are not resorbed during the life of the fish and have potential to provide data relevant to both the biology of the fish and the environment to which the fish has been exposed. Environmental variability based on otoliths can be estimated through measures of stable oxygen isotopes, trace elements, and the widths of both daily and annual increments. Although otoliths can be dated based on measurement of radiocarbon by accelerator mass spectrometry this method is relatively expensive. An alternative method for dating golden perch otoliths is based on measurements of isoleucine D/L ratios. Miller and Rosewater (1995) demonstrated that golden perch otoliths are near a perfect closed system for racemization and that otoliths have potential of dating surrounding sediments older than 100 ka. Despite the suitability of these structures for racemization measurements, many of collections of Pleistocene otoliths from Willandra Lakes are not appropriate for determination of sample age. Most otoliths sampled in the region have been derived from surface collections, while it is recommended that samples should have been buried at least 1 m during most of their history. Therefore, the majority of existing otolith collections are not appropriate for geochronology or palaeothermometry. Nevertheless, when used in conjunction with radiocarbon dates, racemization data may be of value in assessing the relationship among otoliths in an assemblage. Radiocarbon ages and isoleucine D/L ratios were determined for 30 otoliths collected from Willandra Lakes. The rostrum of each otolith was analysed for D/L ratios and a portion of the posterior of the same otolith was analysed for radiocarbon by accelerator mass spectrometry. Sample weights for both analyses ranged from 14.0 to 25.6 mg. The central portion of the

  15. Otoliths as recorders of palaeoenvironments: comparison of radiocarbon age and isoleucine epimerization in Pleistocene golden perch `Macquaria ambigua` otoliths from Willandra Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Kalish, J.M.; Pritchard, C. [Australian National Univ., Canberra, ACT (Australia); Miller, G.H.; Rosewater, A. [Colorado Univ., Boulder, CO (United States). Dept. of Geological Sciences; Tuniz, C.; Lawson, E. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1997-12-31

    Fish otoliths form by the accretion of layers of calcium carbonate and organic-rich material that often form distinctive layers over time scales ranging from days to years. These layers are not resorbed during the life of the fish and have potential to provide data relevant to both the biology of the fish and the environment to which the fish has been exposed. Environmental variability based on otoliths can be estimated through measures of stable oxygen isotopes, trace elements, and the widths of both daily and annual increments. Although otoliths can be dated based on measurement of radiocarbon by accelerator mass spectrometry this method is relatively expensive. An alternative method for dating golden perch otoliths is based on measurements of isoleucine D/L ratios. Miller and Rosewater (1995) demonstrated that golden perch otoliths are near a perfect closed system for racemization and that otoliths have potential of dating surrounding sediments older than 100 ka. Despite the suitability of these structures for racemization measurements, many of collections of Pleistocene otoliths from Willandra Lakes are not appropriate for determination of sample age. Most otoliths sampled in the region have been derived from surface collections, while it is recommended that samples should have been buried at least 1 m during most of their history. Therefore, the majority of existing otolith collections are not appropriate for geochronology or palaeothermometry. Nevertheless, when used in conjunction with radiocarbon dates, racemization data may be of value in assessing the relationship among otoliths in an assemblage. Radiocarbon ages and isoleucine D/L ratios were determined for 30 otoliths collected from Willandra Lakes. The rostrum of each otolith was analysed for D/L ratios and a portion of the posterior of the same otolith was analysed for radiocarbon by accelerator mass spectrometry. Sample weights for both analyses ranged from 14.0 to 25.6 mg. The central portion of the

  16. Does DNA extraction affect the physical and chemical composition of historical cod (Gadus morhua) otoliths?

    DEFF Research Database (Denmark)

    Therkildsen, Nina Overgaard; Eg Nielsen, Einar; Hüssy, Karin;

    2010-01-01

    conflicting interests regarding how the limited and irreplaceable otolith collections should be used. To resolve this, it is important to find out whether DNA extraction damages otoliths such that they can no longer be used for other research purposes or whether individual otoliths can be used in multiple...... applications. We examined the effects of three different DNA extraction methods on the elemental composition, the morphology, and the clarity of annual growth increments for successful age estimation of Atlantic cod (Gadus morhua) otoliths that had been archived for 0–31 years. The three extraction methods...... yielded DNA of comparable quality, and none of the methods caused major damage to the otoliths. Of the element concentrations measured, only Mg and Rb showed considerable changes resulting from DNA extraction. The physical properties of the otolith (morphology and clarity of annual growth increments) were...

  17. Continental paleothermometry and seasonality using the isotopic composition of aragonitic otoliths of freshwater fishes

    Science.gov (United States)

    Patterson, William P.; Smith, Gerald R.; Lohmann, Kyger C.

    To investigate the applicability of oxygen isotope themometry using fish aragonite, the δ18O values of paired otolith and water samples were analyzed from six large modem temperate lakes. Otoliths are accretionaiy aragonitic structures which are precipitated within the sacculus of fish ears. Deep-water obligate benthic species from the hypolimnion of the Laurentian Great Lakes of North America and Lake Baikal, Siberia, provided cold-water end member values for aragonite δ18O. Warm-water values were obtained from naturally grown warm-water stenothermic species and from fish grown in aquaria under controlled conditions. These two groups, which represent growth over a temperature range of 3.2-30.3°C. were employed to determine the oxygen isotope temperature fractionation relationship for aragonite-water: 103lnα = 18.56 (±0.319)·(103)T-1 K -33.49 (±0.307). Empirical calibration of a fish aragonite thennometry equation allows its direct application to studies of paleoclimate. For example, high-resolution sampling of shallow-water eurythermic species coupled with a knowledge of the isotopic composition of meteoric waters can be used to determine seasonal temperature variation. This approach was tested using a modem shallow-water eurythermic species from Sandusky Bay, Lake Erie. Temperatures calculated from carbonate composition agree with meteorological records from the Sandusky Bay weather station for the same time period.

  18. Three-dimensional rendering of otolith growth using phase contrast synchrotron tomography.

    Science.gov (United States)

    Mapp, J J I; Fisher, M H; Atwood, R C; Bell, G D; Greco, M K; Songer, S; Hunter, E

    2016-05-01

    A three-dimensional computer reconstruction of a plaice Pleuronectes platessa otolith is presented from data acquired by the Diamond Light synchrotron, beamline I12, X-ray source, a high energy (53-150 keV) source particularly well suited to the study of dense objects. The data allowed non-destructive rendering of otolith structure, and for the first time allows otolith annuli (internal ring structures) to be analysed in X-ray tomographic images. PMID:27071346

  19. Determining the age of tropical tunas in the Indian Ocean from otolith microstructures

    OpenAIRE

    Sardenne, Fany; Dortel, Emmanuelle; Le Croizier, G.; Million, J.; Labonne, Maylis; Leroy, B.; Bodin, Nathalie; Chassot, Emmanuel

    2015-01-01

    The Indian Ocean Tuna Tagging Program (IOTTP) provided a unique opportunity to assess the viability of estimating the age of tropical tunas from the micro-structural features of otoliths. Here, we analyzed the length measurements and micro-increment counts collected for 506 sagittal otoliths, of which 343 were chemically marked with oxytetracycline, for bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares). Our results show that the otoliths of tropica...

  20. PIXE analysis of otoliths from reared red sea bream, pagrus major (temminck et schlegl)

    International Nuclear Information System (INIS)

    PIXE analysis was applied to estimate mineral concentration in red sea bream otoliths without cutting or polishing. Detected elements include Sr, Fe, Mn and Zn, which are commonly found in the otoliths in marine fishes. Strontium-Calcium concentration ratio is calculated by means of combined X-ray yields. The ratio doesn't indicate clear correlaion with mean reared seawater temperature. It is caused by the diffraction error induced by rough topographies of the otoliths surface. (author)

  1. Modelling of the static and dynamic mechanical properties of human otoliths

    OpenAIRE

    Jäger, Rudolf

    2003-01-01

    The aim of this study is a numerical investigation of the static and dynamic properties of the otoliths. The otoliths are a part of the vestibular system, located in the inner ears. They sense accelerations of the head. In the static case, information retrieved from them indicates the orientation of the head with respect to gravity. Under dynamic conditions, they provide information about the current direction and magnitude of head acceleration. Two important parts of the otoliths can be dist...

  2. Fish otoliths as archives of metal concentrations in the aquatic environment

    International Nuclear Information System (INIS)

    Full text: Little is known of the relationship between the concentrations of metals in the laminations of the fish otolith and that in the environment. It is imperative that a concentration response relationship be demonstrated if otoliths are to be used as archives of metal concentrations in the aquatic environment. The aim of this preliminary study was to determine if there was an increase in concentration of Mn in the laminations of the fish otolith when fish were exposed to an elevated level of this metal. SIMS was used to measure Mn in the otolith. The findings will be discussed

  3. An attempt to analyze fish otoliths by in-air PIXE

    Science.gov (United States)

    Arai, Nobuaki; Sakamoto, Wataru; Maeda, Kuniko

    1996-04-01

    Fish otoliths are generally composed of aragonite crystals. A large number of trace elements such as Sr, Fe, Mn, and Zn are included in the crystal. Especially, Sr enters the crystals much among those metals in the process of precipitation of the calcium carbonate. In addition, it is expected that Sr/Ca concentration ratios can indicate ambient temperature. In-air PIXE was adopted to analyze trace elements in otoliths of juvenile red sea bream. Preliminary results indicated that the Sr/Ca ratios of the otoliths increased proportional to rearing temperature and that PIXE was a fast and convenient technique for determination of several elements in fish otoliths.

  4. The relationship between trace elements in fish otoliths of wild carp and hydrochemical conditions.

    Science.gov (United States)

    Gao, Yonghua; Feng, Qingling; Ren, Dongni; Qiao, Li; Li, Shengrong

    2010-03-01

    The trace element composition of the fish otolith is an indicator of biomineralization. In contrast to other skeletal tissue, the otolith retains its entire original structure and does not absorb any elements after the fish dies. Because otoliths in carp degrade very slowly in the dead body, the information it provides on the environment is retained, even in fossil form. Here, we report our analysis of the trace elements in otoliths of carp and of the water in Donghu Lake and Longhupao Lake, Heilongjiang province, China, where the fish lived. The results revealed that the trace elements found in the carp otoliths were clearly correlated with those found in these water bodies. There were high concentrations of Au, Ba, K, Sr and Zn in both the water and otoliths; in contrast there were high levels of As, Na and Se in water, but low concentrations in otoliths. These results indicate that an analysis of the otoliths of carps provides an accurate procedure for studying the surrounding hydrochemistry conditions. The interaction of the elements during deposition was also studied. The correlation coefficients of 13 trace elements identified in the otoliths in both lakes were calculated. PMID:19093220

  5. Fish inner ear otoliths stop calcium incorporation after vestibular nerve transection.

    Science.gov (United States)

    Anken, R H; Edelmann, E; Rahmann, H

    2000-09-11

    Previous investigations revealed that the growth of fish inner ear otoliths (otolith size and calcium incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In a search for the regulating unit, the vestibular nerve was unilaterally transected in neonatal swordtail fish (Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation and thus otolith growth ceased on the operated head sides, indicating that the brain is significantly involved in regulating otolith growth. PMID:11006979

  6. Epigenetic disruption of cadherin-11 in human cancer metastasis

    OpenAIRE

    Carmona, F.Javier; Villanueva, Alberto; Vidal, August; Muñoz, Clara; Puertas, Sara; Penin, Rosa M; Gomà, Montserrat; Lujambio, Amaia; Piulats, Josep M.; Mesía, Ricard; Sánchez-Céspedes, Montse; Manós, Manel; Condom, Enric; Eccles, Suzanne A; Esteller, Manel

    2012-01-01

    Little is known about the molecular events occurring in the metastases of human tumours. Epigenetic alterations are dynamic lesions that change over the natural course of the disease, and so they might play a role in the biology of cancer cells that have departed from the primary tumour. Herein, we have adopted an epigenomic approach to identify some of these changes. Using a DNA methylation microarray platform to compare paired primary tumour and lymph node metastatic cell lines from the sam...

  7. New Insights into Fish Ecology via Nuclear Microscopy of Otoliths

    International Nuclear Information System (INIS)

    Otoliths, or earstones, are small, biogenic concretions of aragonitic calcium carbonate precipitated on a protein matrix. Otoliths form part of the hearing and balance system in teleost fishes, and grow as the fish grow, providing a continuous biochronology of growth. Various elements are entrained in minor and trace quantities. In particular, strontium is a useful scalar of habitat use when variable environmental gradients exist. By mapping elemental concentrations and ratios with the Lund nuclear microprobe, we have used strontium in many cases as a proxy for salinity, because Sr:Ca values are roughly an order of magnitude higher in marine vs most fresh waters. In addition, zinc shows strong seasonal variations in salmoniform fishes (salmons, charrs, and whitefishes have been tested to date). We present case studies of several species, and discuss exciting future directions in this research that is revolutionizing fisheries ecology

  8. New Insights into Fish Ecology via Nuclear Microscopy of Otoliths

    Science.gov (United States)

    Limburg, K. E.; Elfman, M.; Kristiansson, P.; Malmkvist, K.; Pallon, J.

    2003-08-01

    Otoliths, or earstones, are small, biogenic concretions of aragonitic calcium carbonate precipitated on a protein matrix. Otoliths form part of the hearing and balance system in teleost fishes, and grow as the fish grow, providing a continuous biochronology of growth. Various elements are entrained in minor and trace quantities. In particular, strontium is a useful scalar of habitat use when variable environmental gradients exist. By mapping elemental concentrations and ratios with the Lund nuclear microprobe, we have used strontium in many cases as a proxy for salinity, because Sr:Ca values are roughly an order of magnitude higher in marine vs most fresh waters. In addition, zinc shows strong seasonal variations in salmoniform fishes (salmons, charrs, and whitefishes have been tested to date). We present case studies of several species, and discuss exciting future directions in this research that is revolutionizing fisheries ecology.

  9. Shedding Light on Fish Otolith Biomineralization Using a Bioenergetic Approach

    OpenAIRE

    FABLET, Ronan; Pecquerie, Laure; Pontual, Hélène de; Høie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A. L. M.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent ...

  10. Shedding light on fish otolith biomineralization using a bioenergetic approach

    OpenAIRE

    Fablet, R; Pecquerie, L.; de Pontual, H.; Høie, H.; Millner, R.; Mosegaard, Henrik; Sebastiaan, A.; Kooijman, S. A. L. M.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous ...

  11. OTOLITH MASS ASYMMETRY IN CARANGOIDES CAERULEPINNATUS (RÜPPELL, 1830) (FAMILY: CARANGIDAE) COLLECTED FROM THE SEA OF OMAN

    OpenAIRE

    Laith Jawad

    2013-01-01

    The sagittae mass asymmetry was studied in the teleost Carangoides caeruleopinnatus. The value of the asymmetry was calculated as the difference between the mass of the right and left paired otoliths, divided by average otolith mass. The results show that the absolute value of X in C. caeruleopinnatus does not depend on fish length and otolith growth rate, as it does in other symmetrical fish species. However, the absolute value of otolith mass difference increases with the fish length. The v...

  12. Within-otolith variability in chemical fingerprints: implications for sampling designs and possible environmental interpretation.

    Directory of Open Access Journals (Sweden)

    Antonio Di Franco

    Full Text Available Largely used as a natural biological tag in studies of dispersal/connectivity of fish, otolith elemental fingerprinting is usually analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS. LA-ICP-MS produces an elemental fingerprint at a discrete time-point in the life of a fish and can generate data on within-otolith variability of that fingerprint. The presence of within-otolith variability has been previously acknowledged but not incorporated into experimental designs on the presumed, but untested, grounds of both its negligibility compared to among-otolith variability and of spatial autocorrelation among multiple ablations within an otolith. Here, using a hierarchical sampling design of spatial variation at multiple scales in otolith chemical fingerprints for two Mediterranean coastal fishes, we explore: 1 whether multiple ablations within an otolith can be used as independent replicates for significance tests among otoliths, and 2 the implications of incorporating within-otolith variability when assessing spatial variability in otolith chemistry at a hierarchy of spatial scales (different fish, from different sites, at different locations on the Apulian Adriatic coast. We find that multiple ablations along the same daily rings do not necessarily exhibit spatial dependency within the otolith and can be used to estimate residual variability in a hierarchical sampling design. Inclusion of within-otolith measurements reveals that individuals at the same site can show significant variability in elemental uptake. Within-otolith variability examined across the spatial hierarchy identifies differences between the two fish species investigated, and this finding leads to discussion of the potential for within-otolith variability to be used as a marker for fish exposure to stressful conditions. We also demonstrate that a 'cost'-optimal allocation of sampling effort should typically include some level of within-otolith

  13. Hierarchical structure of the otolith of adult wild carp

    International Nuclear Information System (INIS)

    The otolith of adult wild carp contains a pair of asterisci, a pair of lappilli and a pair of sagittae. Current research works are mainly restricted to the field of the daily ring structure. The purpose of this work is to explore the structural characteristics of carp's otolith in terms of hierarchy from nanometer to millimeter scale by transmission election microscope (TEM) and scanning electron microscope (SEM). Based on the observation, carp's lapillus is composed of ordered aragonite crystals. Seven hierarchical levels of the microstructure were proposed and described with the scheme representing a complete organization in detail. SEM studies show not only the clear daily growth increment, but also the morphology within the single daily increment. The domain structure of crystal orientation in otolith was observed for the first time. Furthermore, TEM investigation displays that the lapillus is composed of aragonite crystals with nanometer scale. Four hierarchical levels of the microstructure of the sagitta are also proposed. The asteriscus which is composed of nanometer scale vaterite crystals is considered to have a uniform structure.

  14. Pre- and post-bomb radiocarbon in fish otoliths

    Science.gov (United States)

    Kalish, John M.

    1993-02-01

    Measurements of radiocarbon in seawater dissolved inorganic carbon (DIC), or suitable proxies such as hermatypic corals, are a valuable source of information on carbon flux and ocean circulation. However, knowledge of the global distribution of both pre- and post-bomb radiocarbon is limited due to the sources of these data. Suitable hermatypic corals are restricted to shallow tropical and subtropical waters and oceanographic collections of seawater are prohibitively expensive. What is needed is a proxy for ocean radiocarbon that can be collected at most latitudes and depths, and which can be reliably aged. Here I report accelerator mass spectrometry analyses of radiocarbon from selected regions of fish otoliths and show that such measurements are suitable for determining both pre- and post-bomb radiocarbon in all oceans and at most depths. Radiocarbon data obtained from otoliths can extend our knowledge of carbon flux in the oceans and atmosphere and help to develop further understanding of the fate of atmospheric CO 2 and ocean circulation. The data presented here represent the first pre- and post-bomb time series of radiocarbon levels from temperate waters. Furthermore, I demonstrate that the dramatic increase in radiocarbon in the atmosphere and oceans, attributable to the atmospheric testing of thermonuclear bombs during the 1950's and 1960's, provides a chemical mark on fish otoliths that is suitable for the validation of age in fishes.

  15. Provenancing fish in freshwaters of the Alpine Foreland using Sr/Ca and 87Sr/86Sr ratios in otoliths and otolith shape parameters

    Directory of Open Access Journals (Sweden)

    Johannes Oehm

    2015-12-01

    Although the studied freshwaters were located only in a 50 km range around lake Chiemsee on a similar geological background, differences in water chemistry, fish otolith chemistry and shape were identified. Species specific differences in reflection of the Sr/Ca ratio of a specific water body were detected. Microchemical and morphological otoliths analyses complemented each other and allowed assigning fish to specific groups of waters of origin. This information provides an important basis for the further application of otolith chemistry and shape analysis in the Alpine foreland for a diverse range of ecological questions.

  16. Evaluation of thyroid-mediated otolith growth of larval and juvenile tilapia.

    Science.gov (United States)

    Shiao, Jen-Chieh; Wu, Su-Mei; Hwang, Yi-Ping; Wu, Done-Ping; Hwang, Pung-Pung

    2008-06-01

    Thyroid-mediated otolith growth in tilapia was evaluated by the ontogenic triiodothyronine (T3) profile revealed by radioimmunoassay during the first month after hatching. Thyroid hormone receptor genes (TRalpha and TRbeta) were cloned and only the expression of TRalpha mRNA, quantified by real-time PCR, was similar to the T3 profile. Variations in otolith growth showed median correlation with the T3 profile and TRalpha mRNA expression pattern. Hypothyroidism and hyperthyroidism were induced in tilapia juveniles and larvae by administration of different concentrations of thiourea (TU) and T3, respectively, for 13 days. T3 and TU had little effect on otolith growth during the larval stage. However, T3 increased otolith growth and TU retarded, or stopped, otolith growth during the juvenile stage. Furthermore, TU treatment caused permanent changes in otolith shape in the ventral area. Otolith growth recovered slowly from hypothyroidism, requiring 2 days to form an increment during the first week. These results suggest that otolith growth, at least during the juvenile stage, is regulated by the thyroid hormones and the process may be mediated by TRalpha. PMID:18515722

  17. The imprint of anthropogenic CO2 emissions on Atlantic bluefin tuna otoliths

    Science.gov (United States)

    Fraile, Igaratza; Arrizabalaga, Haritz; Groeneveld, Jeroen; Kölling, Martin; Santos, Miguel Neves; Macías, David; Addis, Piero; Dettman, David L.; Karakulak, Saadet; Deguara, Simeon; Rooker, Jay R.

    2016-06-01

    Otoliths of Atlantic bluefin tuna (Thunnus thynnus) collected from the Mediterranean Sea and North Atlantic Ocean were analyzed to evaluate changes in the seawater isotopic composition over time. We report an annual otolith δ13C record that documents the magnitude of the δ13C depletion in the Mediterranean Sea between 1989 and 2010. Atlantic bluefin tuna in our sample (n = 632) ranged from 1 to 22 years, and otolith material corresponding to the first year of life (back-calculated birth year) was used to reconstruct seawater isotopic composition. Otolith δ18O remained relatively stable between 1989 and 2010, whereas a statistically significant decrease in δ13C was detected across the time interval investigated, with a rate of decline of 0.05‰ yr- 1 (- 0.94‰ depletion throughout the recorded period). The depletion in otolith δ13C over time was associated with the oceanic uptake of anthropogenically derived CO2.

  18. Using otolith microchemistry and shape to assess the habitat value of oil structures for reef fish.

    Science.gov (United States)

    Fowler, Ashley M; Macreadie, Peter I; Bishop, David P; Booth, David J

    2015-05-01

    Over 7500 oil and gas structures (e.g. oil platforms) are installed in offshore waters worldwide and many will require decommissioning within the next two decades. The decision to remove such structures or turn them into reefs (i.e. 'rigs-to-reefs') hinges on the habitat value they provide, yet this can rarely be determined because the residency of mobile species is difficult to establish. Here, we test a novel solution to this problem for reef fishes; the use of otolith (earstone) properties to identify oil structures of residence. We compare the otolith microchemistry and otolith shape of a site-attached coral reef fish (Pseudanthias rubrizonatus) among four oil structures (depth 82-135 m, separated by 9.7-84.2 km) on Australia's North West Shelf to determine if populations developed distinct otolith properties during their residency. Microchemical signatures obtained from the otolith edge using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) differed among oil structures, driven by elements Sr, Ba and Mn, and to a lesser extent Mg and Fe. A combination of microchemical data from the otolith edge and elliptical Fourier (shape) descriptors allowed allocation of individuals to their 'home' structure with moderate accuracy (overall allocation accuracy: 63.3%, range: 45.5-78.1%), despite lower allocation accuracies for each otolith property in isolation (microchemistry: 47.5%, otolith shape: 45%). Site-specific microchemical signatures were also stable enough through time to distinguish populations during 3 separate time periods, suggesting that residence histories could be recreated by targeting previous growth zones in the otolith. Our results indicate that reef fish can develop unique otolith properties during their residency on oil structures which may be useful for assessing the habitat value of individual structures. The approach outlined here may also be useful for determining the residency of reef fish on artificial reefs, which would

  19. Assessment of D-methionine protecting cisplatin-induced otolith toxicity by vestibular-evoked myogenic potential tests, ATPase activities and oxidative state in guinea pigs.

    Science.gov (United States)

    Lo, Wu-Chia; Chang, Chih-Ming; Liao, Li-Jen; Wang, Chi-Te; Young, Yi-Ho; Chang, Yih-Leong; Cheng, Po-Wen

    2015-01-01

    To date, inadequate study has been devoted to the toxic vestibular effects caused by cisplatin. In addition, no electrophysiological examination has been conducted to assess cisplatin-induced otolith toxicity. The purposes of this study are thus two-fold: 1) to determine whether cervical vestibular-evoked myogenic potentials (VEMPs) and ocular VEMPs are practical electrophysiological methods of testing for cisplatin-induced otolith toxicity and 2) to examine if D-methionine (D-met) pre-injection would protect the otolith organs against cisplatin-induced changes in enzyme activities and/or oxidative status. Guinea pigs were intraperitoneally treated once daily with the following injections for seven consecutive days: sterile 0.9% saline control, cisplatin (5 mg/kg) only, D-met (300 mg/kg) only, or a combination of d-met (300 mg/kg) and cisplatin (5 mg/kg), respectively, with a 30 minute window in between. Each animal underwent the oVEMP and cVEMP tests before and after treatment. The changes in the biochemistry of the otolith organs, including membranous Na(+), K(+)-ATPase and Ca(2+)-ATPase, lipid peroxidation (LPO) levels and nitric oxide (NO) levels, were also evaluated. In the cisplatin-only treated guinea pigs, the mean amplitudes of the oVEMP tests were significantly (ppigs receiving both D-met and cisplatin, the amplitudes of their oVEMP tests were significantly larger (p<0.05) than those of the cisplatin-only group, but smaller (p<0.05) than those of the saline control or D-met-only group. However, no significant difference of the amplitudes of cVEMP tests was noted among the four groups. In comparison with the other three groups, the cisplatin-only group had the lowest (ps<0.05) mean Na(+), K(+)-ATPase and Ca(2+)-ATPase, and the highest (ps<0.05) LPO and NO levels. The oVEMP tests were feasible for the evaluation of cisplatin-related otolith dysfunction. D-Met attenuated the reduced ATPase activities and increased oxidative stress induced by cisplatin

  20. Variation in otolith macrostructure of Japanese flounder ( Paralichthys olivaceus): A method to discriminate between wild and released fish

    Science.gov (United States)

    Katayama, S.; Isshiki, T.

    2007-02-01

    The main objective of this study was to develop a method to discriminate between wild and hatchery-produced Japanese flounder, Paralichthys olivaceus, based on variations in otolith macrostructure. Otoliths of wild flounder were more elliptical than those of hatchery-produced fish, whereas otolith area and marginal coarseness showed no clear differences. Otolith morphometry did not vary significantly with water temperature or feeding conditions in rearing experiments. Reduced ellipticity in the otoliths of hatchery-produced fish could be caused by biotic and abiotic conditions after release. Throughout the study, it was found that otoliths of Japanese flounder reared at 15 and 20 °C regimes showed opaque zones regardless of feeding condition, while otolith of fish reared at 25 °C had translucent zones. The potential of thermal marks and secondary zones as a new mass-marking system is presented.

  1. Comparison of vertebrae and otoliths measured directly and from radiographs

    DEFF Research Database (Denmark)

    Pedersen, Jens

    1997-01-01

    It is general practice among fish ecologists to use indigestible remains such as vertebrae and otoliths in fish stomachs to determine the nature and size of their prey. However, estimation of the relationship between fish length and vertebrae size is a time consuming process when using vertebrae...... from macerated fish. The present study shows that measurement of vertebrae from radiographs of intact fish is a reliable and quick method for estimating the relationship between vertebral length and fish length from a number of reference fish. The relationship between vertebrae size and fish length was...

  2. Reproductive biology of Otolithes cuvieri (Trewavas, 1974) from Mumbai waters

    OpenAIRE

    Telvekar, P.A.; Chakraborty, S. K.; Jaiswar, A.K.

    2005-01-01

    The reproductive biology of Otolithes cuvieri (Trewavas, 1974) is reported in the present communication. The size at first maturity for the females was estimated to be 275 mm. The spawning activity was observed throughout the year with two peaks occurring in April and June. Two prominent peaks of gonadosomatic index (April and June) also support the view of two major spawning. Relative fecundity ranged from 71,574 to 79,680 eggs per 100g of body weight. Relationship of fecundity with fish len...

  3. Do otolith increments allow correct inferences about age and growth of coral reef fishes?

    Science.gov (United States)

    Booth, D. J.

    2014-03-01

    Otolith increment structure is widely used to estimate age and growth of marine fishes. Here, I test the accuracy of the long-term otolith increment analysis of the lemon damselfish Pomacentrus moluccensis to describe age and growth characteristics. I compare the number of putative annual otolith increments (as a proxy for actual age) and widths of these increments (as proxies for somatic growth) with actual tagged fish-length data, based on a 6-year dataset, the longest time course for a coral reef fish. Estimated age from otoliths corresponded closely with actual age in all cases, confirming annual increment formation. However, otolith increment widths were poor proxies for actual growth in length [linear regression r 2 = 0.44-0.90, n = 6 fish] and were clearly of limited value in estimating annual growth. Up to 60 % of the annual growth variation was missed using otolith increments, suggesting the long-term back calculations of otolith growth characteristics of reef fish populations should be interpreted with caution.

  4. Contribution of water chemistry and fish condition to otolith chemistry: comparisons across salinity environments.

    Science.gov (United States)

    Izzo, C; Doubleday, Z A; Schultz, A G; Woodcock, S H; Gillanders, B M

    2015-06-01

    This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium ((86) Sr) and barium ((137) Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish. PMID:26033292

  5. Chemical analysis of endolymph and the growing otolith: fractionation of metals in freshwater fish species.

    Science.gov (United States)

    Melancon, Sonia; Fryer, Brian J; Markham, James L

    2009-06-01

    The fractionation of metals from water to otolith is an area of research that has received relatively limited attention, especially in freshwater systems. The objectives of the present research were to study the metal partitioning between otolith and endolymph of two freshwater species: Lake trout (Salvelinus namaycush), and burbot (Lota lota). We also included the chemical analyses of water and blood from fish of the same species collected in the same area but during different years. These results provide insight regarding the partition of metals between water and fish. This is one of the first studies to provide a range of trace metal concentrations for endolymph and the growing otolith (both aragonite and vaterite) and to directly measure otolith-endolymph partition coefficients for freshwater fish. The trace elements (Mg, Sr, and Ba) most often used as otolith elemental tracers were the ones with the lowest uptake from water to blood. We found that endolymph and whole blood had similar metal concentrations, with Mg and Fe being the only elements enriched in whole blood. Results showed few significant differences in trace metal content between wild lake trout and burbot endolymph (except for K, Mg, and Ba), but significant differences existed between their aragonitic otoliths. These results suggest two different crystallization processes in these species or the presence of different proteins (and/or organic matrices) that would selectively influence elemental incorporation in the otoliths. PMID:19154085

  6. Chemical composition of saccular endolymph and otolith in fish inner ear: lack of spatial uniformity.

    Science.gov (United States)

    Payan, P; Edeyer, A; de Pontual, H; Borelli, G; Boeuf, G; Mayer-Gostan, N

    1999-07-01

    Fish otoliths provide a record of age, growth, and environmental influences. In both trout and turbot, spatial chemical investigation of the endolymph surrounding the otolith (sagitta) showed a lack of uniformity. Proteins, PO(3-)(4), and Mg(2+) were significantly more concentrated in the proximal (facing the macula) than distal zone, whereas the opposite was observed for K(+) and total CO(2) (totCO(2)). Na(+) concentration ([Na(+)]) was 20% higher in the proximal zone in trout but not in turbot. Total Ca and Cl(-) contents were uniformly distributed in both species. We propose that the endolymphatic gradients of protein and totCO(2) concentration within the endolymph are involved in the otolithic biocalcification process. Microchemical analyses of otolith sections by wavelength dispersive spectrometry showed a lack of spatial uniformity in the K/Ca and Na/Ca ratios, whereas the Sr/Ca ratio was uniform. There is a clear relationship between endolymph and otolith [K(+)], but the interpretation of the results for [Na(+)] needs further investigation. Thus the lack of uniformity in the otolith composition must be taken into account when investigating otolith microchemistry. PMID:10409265

  7. Calcium-tracers disclose the site of biomineralization in inner ear otoliths of fish

    Science.gov (United States)

    Beier, M.; Anken, R. H.; Rahmann, H.

    2004-01-01

    Since changing gravity (concerning direction and amplitude) strongly affects inner ear otolith growth and otolithic calcium incorporation in developing fish, it was the aim of the present study to locate the site of mineralization in order to gain cues and insights into the provenance of the otoliths inorganic compounds. Therefore, larval cichlid fish (Oreochromis mossambicus) were incubated in the calcium-tracer alizarin complexone (AC; red fluorescence). After maintenance in aquarium water for various periods (1, 2, 3, 6, 9 and 12 h; 1, 2, 3, 5, 6, 7, 15, 29, 36 and 87 d), the animals were incubated in the calcium-tracer calcein (CAL; green fluorescence). AC thus labeled calcium being incorporated at the beginning of the experiment and would subsequently accompany calcium in the course of a possible dislocation, whereas CAL visualized calcium being deposited right at the end of the test. Subsequently, the otoliths were analyzed using a laser scanning microscope and it was shown that the initial site of calcium incorporation was located directly adjacent to the sensory epithelium and the otolithic membrane. Later, calcium deposits were also found on further regions of the otoliths' surface area, where they had been shifted to in the course of dislocation. This finding strongly indicates that the sensory epithelium plays a prominent role in otolithic biomineralization, which is in full agreement with an own electron microscopical study [ELGRA News 23 (2003) 63].

  8. Otolith shape analysis of the austral sardine (Sprattus fuegensis in the Patagonian inner sea of Chile.

    Directory of Open Access Journals (Sweden)

    Luis A Cubillos

    2015-11-01

    Full Text Available The austral sardine has an extensive distribution within inner and outer waters along fiords, channels, and the continental shelf of the Chilean Patagonia, from Puerto Montt to Tierra del Fuego and extending to southern Argentina. With the aim of determining differences in morphology and shape of sagittal otoliths of the austral sardine, samples were obtained from inner waters of Chiloé (42ºS-43ºS, Aysén (44ºS-46ºS, Punta Arenas (54ºS, and from Argentinian waters. Traditional morphometry analysis considered length, width, area, perimeter, and size-based shape descriptors of otoliths. Instead, geometric morphometry was an outline otolith analysis on the basis of elliptic Fourier descriptors through multivariate statistical methods. Both approached showed intraspecific variability in otolith shape of austral sardine, with otoliths from inner waters of Chiloé statistically differenced from the Aysén Region, but with an important degree of mix between zones. Otoliths from Punta Arenas were excluded from the study because they were smaller, without the outline characteristic of the adult specimens. The sagittal otolith from inner waters of Chiloé exhibited an elliptical shape, defined rostrum, and concave antirostrum, while otoliths from the Aysén Región showed rounded shape along the dorsal and ventral borders, without defined postrostrum and antirostrum. The otolith rostrum of specimens from inner waters of Chiloé was very well defined, being this the main morphological trait generating differences with the rest of the zones.

  9. Calcium-Tracers disclose the Site of Biomineralisation in inner Ear Otoliths of Fish

    Science.gov (United States)

    Beier, M.; Anken, R.; Rahmann, H.

    Since changing gravity (concerning direction and amplitude) strongly affects inner ear otolith growth and otolithic calcium incorporation in developing fish, it was the aim of the present study to locate the site of mineralisation in order to gain cues and insights into the provenance of the otoliths inorganic compounds. Therefore, larval cichlid fish ( reochromis mossambicus) were incubated in theO calcium-tracer alizarin complexone (AC; red fluorescence). After maintenance in aquarium water for various periods (1h, 2h, 3h, 6h, 9h, 12h, 1d, 2d, 3d, 5d, 6d, 7d, 15d, 29d, 36d and 87d), the animals were incubated in the calcium-tracer calcein (CAL; green fluorescence). AC thus labelled calcium being incorporated at the beginning of the experiment and would subsequently accompany calcium in the course of a possible dislocation, whereas CAL visualized calcium being deposited right at the end of the test. Subsequently, the otoliths were analysed using a laser-scanning microscope and it was shown that the initial site of calcium incorporation was located directly adjacent to the sensory epithelium and the otolithic membrane. Later, calcium deposits were also found on further regions of the otoliths' surface area, where they had been shifted to in the course of dislocation. This finding strongly indicates that the sensory epithelium plays a prominent role in otolithic biomineralisation, which is in full agreement with an electron microscopical study (Ibsch et al., this issue). Future studies will address the question, as of whether either the sensory epithelium is directly involved in the provision of calcium (and possibly further inorganic compounds of the otoliths) or, in contrast, that the otoliths' proteinacious matrix exclusively exhibits nucleation centers for calcium incorporation in an area adjacent to the receptor epithelium. This work was financially supported by the German A erospace Center (DLR) e.V. (FKZ: 50 WB 9997).

  10. A bioenergetic approach to model and reconstruct individual life traits from fish otoliths

    DEFF Research Database (Denmark)

    Fablet, Ronan; Pecquerie, Laure; Høie, Hans;

    2012-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm‐following formation provides individual records of the age, the individual history, and the natural environment of extinct and living fish species. Such data are critical for ecosy...... observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves...

  11. Validation and efficacy of transgenerational mass marking of otoliths in viviparous fish larvae.

    Science.gov (United States)

    Kuroki, M; Buckley, R M; Leclair, L L; Hauser, L

    2010-07-01

    Transgenerational mass marking of viviparous fish larvae in vivo was validated by intra-muscular injection of elemental strontium chloride (SrCl(2)) in gestating females and detection of the Sr in the otoliths of developing larvae. All otoliths of brown rockfish Sebastes auriculatus larvae produced from SrCl(2)-injected females showed enriched Sr:Ca ratios near the otolith edges, and the signatures did not appear to be affected by the anterior, centre and posterior positions of larvae within the ovary. Results from the present study indicate that transgenerational marking is a highly reliable technique for marking large numbers of extremely small viviparous fish larvae. PMID:20646154

  12. Otolith Sr concentration analyzed by PIXE in Ariake estuary-dependent sea bass juveniles

    International Nuclear Information System (INIS)

    Japanese sea bass (Lateolabrax japonicus) is a typical euryhaline marine fish and frequently migrates from salt to freshwater environments during early life stages. We hypothesized that strontium concentrations in the otolith could be a useful index to examine freshwater entry because of its lower concentration in freshwater. Otoliths of Japanese sea bass juveniles collected in the Chikugo river and estuary were analyzed by Particle Induced X-ray Emission (PIXE) to see relationship between strontium concentration and ambient salinity. Strontium concentrations in otoliths of sea bass juveniles are significantly lower in the river samples than in brackish water samples. (author)

  13. Validating the use of embryonic fish otoliths as recorders of sublethal exposure to copper in estuarine sediments

    International Nuclear Information System (INIS)

    In this study we explore the use of fish otoliths (‘earbones’) as a tool for detecting exposure to heavy metals in sediments. Because otoliths are metabolically inert and incorporate chemical impurities during growth, they can potentially provide a more permanent record of pollutant exposure history in aquatic environments than soft tissues. To validate this technique we cultured embryos of a native Australian fish, the common Galaxias (Galaxias maculatus), in the laboratory on sediments spiked with copper in a concentration gradient. Our aims were to test whether exposure to copper contaminated sediments is recorded in the otoliths of embryos and determine over what range in concentrations we can detect differences in exposure. We found elevated copper levels in otoliths of embryos exposed to high copper concentrations in sediments, suggesting that otoliths can be used as a tool to track a history of exposure to elevated copper levels in the environment. -- Highlights: •Our aim was to determine if exposure to Cu is recorded in embryonic fish otoliths. •Fish eggs were cultured on Cu-spiked sediments in a gradient of concentrations. •Fish do uptake and incorporate Cu into their otoliths during development. •High sediment Cu concentrations resulted in high otolith Cu concentrations. •With further validation, otoliths could be used to track a history of Cu exposure. -- We use sediments spiked with Cu to examine the uptake of heavy metals into embryonic fish otoliths as a novel tool for tracking pollution exposure history

  14. Use of fish-otolith-length regressions to infer size of double-crested cormorant prey fish from recovered otoliths in Lake Ontario

    Science.gov (United States)

    Ross, Robert M.; Johnson, James H.; Adams, Connie M.

    2005-01-01

    To provide a method for estimating fish size from fish otoliths for forensic applications or other predictive uses, morphometric measurements were obtained from three centrarchid fishes (pumpkinseed [Lepomis gibbosus], rock bass [Ambloplites rupestris], and smallmouth bass [Micropterus dolomieu]), two percids (yellow perch [Perca flavescens] and walleye [Stizostedion vitreum]), and one clupeid (alewife [Alosa pseudoharengus]) from the eastern basin of Lake Ontario. These species are the principal or economically important prey of Double-crested Cormorants (Phalacrocorax auritus), whose diet can be determined from regurgitated digestive pellets containing fish otoliths. A fuller understanding of the ecosystem roles of cormorants requires estimation of prey-fish size, obtainable from regressions of otolith length on fish length. Up to 100 fish of each species were collected from eastern Lake Ontario and measured for total length and otolith length. Least-squares regressions of otolith length on fish length were calculated for all species, covering life-stage ranges of immature fish to large adults near maximum known size. The regressions with 95% confidence intervals may be applicable outside the Lake Ontario ecosystem if used with caution.

  15. Otolith Asymmetry and kinetotic Behaviour of Fish in Parabolic Flights and under simulated Parabolic Flight "Micro"Gravity - a Drop-Tower Experiment

    Science.gov (United States)

    Knie, M.; Hilbig, R.; Anken, R.

    We have shown earlier that some fish of a given batch reveal motion sickness a kinetosis at the transition from earth gravity to diminished gravity The percentual ratios of the various types of behaviour normal swimming and kinetotic swimming kinetotic specimens revealed looping responses LR or spinning movements SM however highly differed depending on the quality of diminished gravity Anken and Hilbig Microgravity Sci Technol 15 52-57 2004 Whereas kinetoses were exhibited by some 90 of the individuals who had experienced flights at high quality microgravity HQM 10-6g ZARM drop-tower only some 15-25 depending on the batch of all animals had shown a kinetotic behaviour during parabolic aircraft flights PFs low quality microgravity LQM 0 03-0 05g Probably LQM is sufficient for most fish to be perceived - in relation to the individual shape or weight of otoliths and thus the performance of the vestibular system - and used as a cue for postural control In striking contrast to the results gained using PF specimens according to which otolith asymmetry differences in the size and calcium incorporation of the inner ear stones between the left and right side of the body was significantly higher in kinetotic specimens as compared to normally swimming fish a comparable asymmetry between the kinetotically and normally swimming drop-tower samples could statistically not be verified Anken et al Adv Space Res submitted The present study was designed to further elucidate the role of otolith asymmetry concerning an individually different

  16. Strontium content in otoliths of common fish species in the northern Baltic Sea

    International Nuclear Information System (INIS)

    Full text: The salinity of water in the northern Baltic Sea forms a gradient as it receives fresh water from several large rivers in the north and salty water by infrequent inflows of North Sea water in the south. The salinity of brackish water in the north-south direction (700 km) changes from about 3 to 7%. In an attempt to use the salinity gradient to study migration patterns, sagittae otoliths were collected from common fish species caught at different locations along the Finnish west coast. Otoliths from fishes caught in fresh-water lakes in Finland and Estonia were also included in the study for comparison. Part of the otoliths was grind and the powder was pressed to pellets which were irradiated in air with an ion beam from the Abo Akademi cyclotron and the emitted X-rays were measured. Other otoliths were embedded in epoxy and polished to reveal the ring structure. These prepared otoliths were irradiated with the ion beam to determine elemental profiles. Furthermore, XRD was applied to study the crystal structure and to identify the minerals in the otoliths. The strontium level of water is usually related to its salinity, and as the strontium ions are able to replace calcium ions in fish otoliths [1], the strontium content in fish otoliths from the same locations is expected to be very similar. However, the PIXE analyses revealed large differences in the strontium content between otoliths from different species of fish caught at the same locations. The strontium concentration in otoliths of perch and pike from the Aland Islands was about 1600 μg/g and of common whitefish 3600 μg/g. The strontium concentration in perch otoliths from the Oravais archipelago, about 400 km north of the Aland Islands, was 1400 μg/g. Corresponding concentration in otoliths of perch and pike caught in fresh-water lakes was 200 μg/g and of common whitefish from Saadjarve 400 μg/g and from Lake Inari 1000 μg/g. Otoliths of perch contained no detectable amounts of zinc (Iower

  17. Morphology and microchemistry of the otoliths of the inner ear of anuran larvae.

    Science.gov (United States)

    Bassó, Agustín; Peltzer, Paola Mariela; Lajmanovich, Rafael Carlos; Attademo, Andrés Maximiliano; Junges, Celina María; Chialvo, Dante R

    2016-05-01

    To navigate in space most vertebrates need precise positional cues provided by a variety of sensors, including structures in the inner ear, which are exquisitely sensitive to gravity and linear acceleration. Although these structures have been described in many vertebrates, no information is available for anuran larvae. The purpose of our study was to describe, for the first time, the size, complexity and microchemistry of the saccular otoliths of the larva of 13 anuran species from central Argentina, using electron microscopy and X-ray spectroscopy (N = 65). We concluded that a) these structures differ in area, perimeter, otolith relative size and fractal dimension, but are similar in terms of their microchemistry when compared by spatial guilds, b) that nektonic species have larger otoliths than nektonic-benthic and benthic species and c) that benthic species have larger otolith relative size than nektonic-benthic and nektonic species. PMID:26899343

  18. Otolith Formation in A Mutant Medaka Fish with A Deficiency in Gravity- Sensing

    Science.gov (United States)

    Mizuno, R.; Ijiri, K.

    Formation of otoliths in Medaka fish (Oryzias latipes) were studied in the normal (wild-type) fish and in a mutant strain called ha. In the normal fish, two pairs of otoliths (Lapillus and Sagitta) are formed during embryonic development, and the most posterior otolith (Asteriscus) are formed later (about 30 days after hatching). In the mutant strain ha, though Sagittae are formed, Lapilli are absent at hatching. Asterisca are formed normally. Various abnormalities in the formation of Sagittae were detected in ha strain, however, they eventually took normal shapes and positions on the maculae. After hatching, in some ha fish, Lapilli are formed. On 30 days and 40 days after hatching, the appearance of Lapilli were examined by X-ray photography. The results showed that some fis h had a complete pair, some had only one otolith either at the right or left side, and the rest of fish lacked Lapilli completely.

  19. Otolith chemistry of prey fish consumed by a fish predator: does digestion hinder Russian doll techniques?

    Science.gov (United States)

    Phelps, Q E; Noatch, M R; Lewis, H A; Myers, D J; Zeigler, J M; Eichelberger, J S; Saltzgiver, M J; Whitledge, G W

    2009-12-01

    The effect of digestion by a predatory fish (largemouth bass Micropterus salmoides) on stable isotopic (delta(13)C and delta(18)O) and trace elemental (Sr:Ca and Ba:Ca) compositions of prey fish (bluegill Lepomis macrochirus) otoliths was investigated in a laboratory experiment. Trace element and stable-isotopic signatures of L. macrochirus otoliths were not significantly altered for up to 16 h after L. macrochirus were consumed by M. salmoides. Prey fish otoliths recovered from predator digesta can retain environmental stable isotopic and trace elemental signatures, suggesting that determination of environmental history for prey fishes by stable-isotope and trace-element analysis of otoliths recovered from stomachs of piscivorous fishes will be feasible. PMID:20738510

  20. Using data storage tags to link otolith macrostructure in Baltic cod Gadus morhua with environmental conditions

    DEFF Research Database (Denmark)

    Hüssy, Karin; Nielsen, Birgitte; Mosegaard, Henrik; Worsøe Clausen, Lotte

    2009-01-01

    We examined otolith opacity of Baltic cod in relation to environmental conditions in order to evaluate the formation mechanisms of seasonal patterns used in age determination. Adult fish were tagged with data storage tags (DSTs) and a permanent mark was induced in the otoliths by injection of a...... strontium chloride solution. Based on environmental conditions experienced, fish were classified into different behavioural types: non-reproducing 'non-spawner', and 'spawner' undertaking spawning migrations. Otolith opacity, an indicator of otolith and fish somatic growth and condition, was examined in...... expected-but in non-spawning fish only. In spawners, the general trend was a decrease in opacity from pre- to post spawning. A significant - but positive - temperature effect was only found in the pre-spawning period. The negative effects during and following spawning were not significant. In spawners...

  1. Otolith Growth and macular Carbonic Anhydrase Reactivity in larval Fish after Development at simulated Microgravity

    Science.gov (United States)

    Baur, U.; Hilbig, R.; Anken, R.

    Otolith growth in terms of mineralisation mainly depends on the enzyme carbonic anhydrase (CA). CA is located in specialized, mitochondria-rich macular cells (ionocytes), which are involved in the endolymphatic ion exchange, and the enzyme is responsible for the provision of the pH-value necessary for otolithic calcium carbonate deposition. Since it has been shown earlier that hypergravity slows down inner ear otolith growth in developing fish via a down-regulation of CA reactivity, we were prompted to elucidate whether (simulated) microgravity would possibly yield opposite effects. Therefore, larval siblings of cichlid fish (Oreochromis mossambicus) were housed in a submersed, two-dimensional clinostat (tube) during their development. Subsequently, the "physical capacity" (i.e., size) of the otoliths was measured, CA was histochemically demonstrated in ionocytes, and enzyme reactivity was determined densitometrically. The respective data will be communicated at the meeting. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 9997).

  2. Effects of simulated weightlessness on fish otolith growth: Clinostat versus Rotating-Wall Vessel

    Science.gov (United States)

    Brungs, Sonja; Hauslage, Jens; Hilbig, Reinhard; Hemmersbach, Ruth; Anken, Ralf

    2011-09-01

    Stimulus dependence is a general feature of developing sensory systems. It has been shown earlier that the growth of inner ear heavy stones (otoliths) of late-stage Cichlid fish ( Oreochromis mossambicus) and Zebrafish ( Danio rerio) is slowed down by hypergravity, whereas microgravity during space flight yields an opposite effect, i.e. larger than 1 g otoliths, in Swordtail ( Xiphophorus helleri) and in Cichlid fish late-stage embryos. These and related studies proposed that otolith growth is actively adjusted via a feedback mechanism to produce a test mass of the appropriate physical capacity. Using ground-based techniques to apply simulated weightlessness, long-term clinorotation (CR; exposure on a fast-rotating Clinostat with one axis of rotation) led to larger than 1 g otoliths in late-stage Cichlid fish. Larger than normal otoliths were also found in early-staged Zebrafish embryos after short-term Wall Vessel Rotation (WVR; also regarded as a method to simulate weightlessness). These results are basically in line with the results obtained on Swordtails from space flight. Thus, the growth of fish inner ear otoliths seems to be an appropriate parameter to assess the quality of "simulated weightlessness" provided by a particular simulation device. Since CR and WVR are in worldwide use to simulate weightlessness conditions on ground using small-sized specimens, we were prompted to directly compare the effects of CR and WVR on otolith growth using developing Cichlids as model organism. Animals were simultaneously subjected to CR and WVR from a point of time when otolith primordia had begun to calcify both within the utricle (gravity perception) and the saccule (hearing); the respective otoliths are the lapilli and the sagittae. Three such runs were subsequently carried out, using three different batches of fish. The runs were discontinued when the animals began to hatch. In the course of all three runs performed, CR led to larger than normal lapilli, whereas WVR

  3. Validation of daily increment formation in otoliths for Gymnocypris selincuoensis in the Tibetan Plateau, China

    OpenAIRE

    Ding, Chengzhi; Chen, Yifeng; He, Dekui; Tao, Juan

    2015-01-01

    Daily increment validation in fish otolith is fundamental to studies on fish otolith microstructure, age determination and life history traits, and thus is critical for species conservation and fishery management. However, it has never been done for Schizothoracine fish, which is the dominant component of fish fauna in the Tibetan Plateau. This study validated the daily increment formation of Gymnocypris selincuoensis, as a representative of Schizothoracine fish, by monitoring the growth of h...

  4. Documenting utility of paddlefish otoliths for quantification of metals using inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Long, James M.; Schaffler, James J.

    2013-01-01

    RATIONALE The otoliths of the inner ear of fishes record the environment of their surrounding water throughout their life. For paddlefish (Polyodon spathula), otoliths have not been routinely used by scientists since their detriments were outlined in the early 1940s. We sought to determine if paddlefish otoliths were useful for resolving elemental information contained within. METHODS Adult paddlefish were collected from two wild, self-sustaining populations in Oklahoma reservoirs in the Arkansas River basin. Juveniles were obtained from a hatchery in the Red River basin of Oklahoma. Otoliths were removed and laser ablation, inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify eight elements (Li, Mg, Mn, Rb, Sr, Y, Ba, and Pb) along the core and edge portions, which were analyzed for differences between otolith regions and among paddlefish sources. RESULTS Differences were found among samples for six of the eight elements examined. Otoliths from Red River basin paddlefish born in a hatchery had significantly lower amounts of Mg and Mn, but higher levels of Rb than otoliths from wild paddlefish in the Arkansas River basin. Concentrations of Y, Sr, and Ba were reduced on the edges of adult paddlefish from both reservoirs compared with the cores. CONCLUSIONS This research shows the utility of using an ICP-MS analysis of paddlefish otoliths. Future research that seeks to determine sources of paddlefish production, such as which reservoir tributaries are most important for reproduction or what proportion of the population is composed of wild versus hatchery-produced individuals, appears promising. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  5. Experimental evidence of complex relationships between the ambient salinity and the strontium signature of fish otoliths

    OpenAIRE

    Panfili, Jacques; Darnaude, A. M.; Vigliola, Laurent; Jacquart, A.; Labonne, Maylis; Gilles, Sylvain

    2015-01-01

    The otolith strontium:calcium ratio (Sr:Ca) has been widely used to assess the connectivity between fish populations in ocean, estuarine and freshwater environments as the concentration of Sr in the otoliths is strongly correlated with water salinity. This correlation was tested experimentally in hypersaline conditions by submitting the extremely euryhaline tilapia species Sarotherodon melanotheron heudelotii (Cichlidae), found throughout West African continental waters and commonly used as a...

  6. On the automatic detection of otolith features for fish species identification and their age estimation

    OpenAIRE

    Sória Pérez, José A. (José Antonio)

    2013-01-01

    This thesis deals with the automatic detection of features in signals, either extracted from photographs or captured by means of electronic sensors, and its possible application in the detection of morphological structures in fish otoliths so as to identify species and estimate their age at death. From a more biological perspective, otoliths, which are calcified structures located in the auditory system of all teleostean fish, constitute one of the main elements employed in the study and mana...

  7. Physiology of Developing Gravity Receptors and Otolith-Ocular Reflexes in Rat

    Science.gov (United States)

    Blanks, Robert H.

    1997-01-01

    This proposal had the long-term objective of examining the effects of microgravity on the physiology of the adult and developing mammalian gravity receptors. The grant outlined three-years of ground-based studies to examine. 1) the physiologic responses or otolith afferents in the adult rat and during postnatal development, and 2) the otolith organ contributions to the vertical vestibulo-ocular (VOR) and postural reflexes.

  8. An evaluation of the precision of fin ray, otolith, and scale age determinations for brook trout

    Science.gov (United States)

    Stolarski, J.T.; Hartman, K.J.

    2008-01-01

    The ages of brook trout Salvelinus fontinalis are typically estimated using scales despite a lack of research documenting the effectiveness of this technique. The use of scales is often preferred because it is nonlethal and is believed to require less effort than alternative methods. To evaluate the relative effectiveness of different age estimation methodologies for brook trout, we measured the precision and processing times of scale, sagittal otolith, and pectoral fin ray age estimation techniques. Three independent readers, age bias plots, coefficients of variation (CV = 100 x SD/mean), and percent agreement (PA) were used to measure within-reader, among-structure bias and within-structure, among-reader precision. Bias was generally minimal; however, the age estimates derived from scales tended to be lower than those derived from otoliths within older (age > 2) cohorts. Otolith, fin ray, and scale age estimates were within 1 year of each other for 95% of the comparisons. The measures of precision for scales (CV = 6.59; PA = 82.30) and otoliths (CV = 7.45; PA = 81.48) suggest higher agreement between these structures than with fin rays (CV = 11.30; PA = 65.84). The mean per-sample processing times were lower for scale (13.88 min) and otolith techniques (12.23 min) than for fin ray techniques (22.68 min). The comparable processing times of scales and otoliths contradict popular belief and are probably a result of the high proportion of regenerated scales within samples and the ability to infer age from whole (as opposed to sectioned) otoliths. This research suggests that while scales produce age estimates rivaling those of otoliths for younger (age > 3) cohorts, they may be biased within older cohorts and therefore should be used with caution. ?? Copyright by the American Fisheries Society 2008.

  9. Age, growth and distribution of the Antarctic fish Chaenocephalus aceratus based on otoliths

    OpenAIRE

    Ryszard Jacek Traczyk

    2015-01-01

    The Chaenocephalus aceratus were sampled in the summer between 1979 and 1990 at South Georgia Is. The problems of ageing Antarctic fish Channichthyidae are commonly known (Kock, 1989; Le_François, 2014; Campana, 2014) they have not scales and their bones undergo constant and large reduction (Żabrowski, 2000). It was found that the otoliths of C. aceratus show daily pattern of microincrements as otoliths of similar species Pseudochaenichthys georgianus, Champsocephalus gunnari and fishes both ...

  10. Relationships between otolith size and fish length in some mesopelagic teleosts (Myctophidae, Paralepididae, Phosichthyidae and Stomiidae).

    Science.gov (United States)

    Battaglia, P; Malara, D; Ammendolia, G; Romeo, T; Andaloro, F

    2015-09-01

    Length-mass relationships and linear regressions are given for otolith size (length and height) and standard length (LS ) of certain mesopelagic fishes (Myctophidae, Paralepididae, Phosichthyidae and Stomiidae) living in the central Mediterranean Sea. The length-mass relationship showed isometric growth in six species, whereas linear regressions of LS and otolith size fit the data well for all species. These equations represent a useful tool for dietary studies on Mediterranean marine predators. PMID:26242808

  11. Spatial Expression of Otolith Matrix Protein-1 and Otolin-1 in Normally and Kinetotically Swimming Fish.

    Science.gov (United States)

    Weigele, Jochen; Franz-Odendaal, Tamara A; Hilbig, Reinhard

    2015-10-01

    Kinetosis (motion sickness) has been repeatedly shown to affect some fish of a given clutch following the transition from 1g to microgravity or from hypergravity to 1g. This susceptibility to kinetosis may be correlated with irregular inner ear otolith growth. Otoliths are mainly composed of calcium carbonate and matrix proteins, which play an important role in the process of otolith mineralization. Here, we examine the morphology of otoliths and the expression pattern of the major otolith proteins OMP-1 and otolin-1 in a series of hypergravity experiments. In the utricle, OMP-1 is present in centripetal (medial) and centrifugal (lateral) regions of the meshwork area. In the saccule, OMP-1 was expressed within a dorsal and a ventral narrow band of the meshwork area opposite to the periphery of the sulcus acusticus. In normal animals, the spatial expression pattern of OMP-1 reaches more posteriorly in the centrifugal aspect and is considerably broader in the centripetal portion of the utricle compared to kinetotic animals. However, otolin-1 was not expressed in the utricule. In the saccule, no differences were observed for either gene when comparing normal and kinetotically behaving fish. The difference in the utricular OMP-1 expression pattern between normally and kinetotically swimming fish indicates a different otolith morphology and thus a different geometry of the otoliths resting on the corresponding sensory maculae. As the utricle is the endorgan responsible for sensing gravity, the aberrant morphology of the utricular otoliths, based on OMP-1 expression, likely leads to the observed kinetotic behavior. PMID:26096990

  12. Effects of vestibular nerve transection on the calcium incorporation of fish otoliths

    Science.gov (United States)

    Anken, Ralf H.; Edelmann, Elke; Rahmann, Hinrich

    2001-08-01

    Previous investigations revealed that the growth of fish inner ear otoliths (otolith size and calcium-incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In search for the regulating unit, the vestibular nerve was transected unilaterally in neonate swordtail fish ( Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation ceased on the transected head sides, indicating that calcium uptake is neurally regulated.

  13. Incorporation of magnesium into fish otoliths: Determining contribution from water and diet

    Science.gov (United States)

    Woodcock, S. H.; Munro, A. R.; Crook, D. A.; Gillanders, B. M.

    2012-10-01

    Magnesium is a commonly measured element in otolith chemistry analysis and is often included in the suite of elements used to discriminate fish from different environments. Poor relations between Mg in water and otolith chemistry are, however, often found. We examined the uptake of Mg into the otoliths of a freshwater fish (silver perch Bidyanus bidyanus), to determine the extent to which this element can be used to record previous environmental conditions. Silver perch fingerlings were reared for 30 days in water with four concentrations of Mg (14.5, 36.6, 52.1 and 69.6 mg L-1) and fed on a diet supplemented with a combination of natural Mg and enriched 26Mg at five concentrations (1496, 1626, 1902, 2005 and 2036 μg g-1). Enriched 26Mg was added to the diet to achieve a 26Mg/25Mg ratio that was different from the natural ratio, such that the relative contribution of water and diet to Mg incorporated into otoliths could be determined. Enriching the diet with 26Mg resulted in an isotope shift in the otolith of silver perch from the natural 26Mg/25Mg ratio of 1.10-1.42; however, this was not as high as the ratio in the diet (> 3.7) suggesting that the fish did not fully incorporate Mg from the diet. Water was the primary source of otolith Mg, contributing on average > 80% to otolith Mg (range 74-95%). The fact that Mg concentrations in the otolith did not change in response to Mg concentrations in the water or diet, indicates that Mg is likely physiologically regulated and therefore is not a reliable environmental indicator.

  14. Neuronal feedback between brain and inner ear for growth of otoliths in fish

    Science.gov (United States)

    Anken, R. H.; Edelmann, E.; Rahmann, H.

    Previous investigations revealed that fish inner ear otolith growth (concerning otolith size and calcium-incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In search for the regulating unit, the vestibular nerve was unilaterally transected in neonate swordtail fish ( Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation ceased on the transected head sides, indicating that calcium uptake is neurally regulated.

  15. Swimming Behaviour and Otolith Characteristics of wildtype and mutant Zebrafish (AIE) under diminished Gravity Conditions

    Science.gov (United States)

    Weigele, J.; Anken, R.; Hilbig, R.

    During microgravity humans often suffer from sensorimotor disorders e g motion sickness a kinetosis Using fish as vertebrate model systems we could previously provide ample evidence that the individually different susceptibility to such disorders is based on an individually differently pronounced asymmetric mineralisation calcification of inner ear stones otoliths In the course of a preliminary study we subjected mutant zebrafish Danio rerio due to malformation of the inner ear - see below - this mutant was termed Asymmetric Inner Ear AIE to diminished gravity conditions during parabolic aircraft flight PF As compared to wildtype WT animals the mutants showed a pronounced kinetotic behaviour The gross-morphology of the inner ears of AIE and WT animals strikingly differed In WT specimens the saccular otoliths were located at the periphery of the inner ear whereas the utricular stones were positioned mediad as it is usually the case in teleosts in most AIE animals dissected however the respective otoliths were positioned in an opposite arrangement Moreover the mutants sported transparent otoliths whereas the otoliths of WT specimens had an opaque appearance This finding clearly indicates that mutant otoliths differed from wildtype ones in their lattice structure i e the calcium carbonate polymorph and thus the compostion of the proteinacious matrix which is a template for calcium carbonate deposition In the course of the present study the PF experiment is scheduled to be carried out in March 2006 we intend to statistically verify

  16. Strontium and zinc concentrations in otoliths of common fish species in the northern Baltic Sea

    Science.gov (United States)

    Lill, J.-O.; Himberg, M.; Harju, L.; Ek, P.; Lindroos, A.; Wiklund, T.; Gunnelius, K.; Smått, J.-H.; Heselius, S.-J.; Hägerstrand, H.

    2014-01-01

    Otoliths of perch (Perca fluviatilis), pike (Esox lucius) and European whitefish (Coregonus lavaretus) caught at different locations in the northern Baltic Sea along the Finnish west coast and at some rivers and lakes were subjected to elemental analyses with particle induced X-ray emission and laser ablation inductively coupled plasma mass spectrometry. The strontium concentration in otoliths from whitefish (˜3300 μg/g) was 2-3 times higher than that of perch and pike (˜1400 μg/g), while within species the strontium concentration of otoliths from fish caught at different locations was in the same range. The strontium concentrations were lowest in fish from the lakes (˜450 μg/g). Whitefish otoliths contained more zinc (˜60 μg/g) than those of pike (˜30 μg/g), while the zinc concentration in perch otoliths were below the detection limit. No spatial intraspecies variations in zinc concentrations were observed. X-ray diffraction showed that the otoliths consisted of aragonite solely.

  17. Effect of water salinity on the elemental composition of otoliths from tridentiger obscurus obscurus

    International Nuclear Information System (INIS)

    The effect of water salinity on the elemental composition of sagittae (otoliths) taken from male gobiid fishes, Tridentiger obscurus obscurus, reared at a constant salinity (freshwater, 50% seawater and 100% seawater) for one month at 20degC, was studied using particle induced X-ray emission (PIXE). Nine elements were detected in the otoliths; Ca, Cl, Sr, K, P, Zn, Mn, Fe and Cu. The PIXE technique was proved to be an effective means for performing multielement analysis in small fish otoliths. The Cl, K and Sr concentrations, and each of their concentration ratios with Ca in the otoliths, were positively proportional to salinity of the fish rearing. The Mn and Zn concentrations, and Mn/Ca and Zn/Ca concentration ratios, were inversely proportional to the respective rearing salinity. No significant changes in Ca, P, Fe and Cu concentrations and P/Ca, Fe/Ca and Cu/Ca concentration ratios in the otoliths were found. These results suggest that it is possible to use the relationship between the elemental composition of otoliths and the environmental salinity as a means of reconstructing the salinity history of migratory fish. (author)

  18. Influence of hypergravity on fish inner ear otoliths: II. Incorporation of calcium and kinetotic behaviour

    Science.gov (United States)

    Beier, M.; Anken, R. H.; Rahmann, H.

    Larval siblings of cichlid fish ( Oreochromis mossambicus) were subjected to hypergravity (hg; 3g, 14 days) during development. Following the transfer to 1g (i.e., stopping the centrifuge) they were seperated into normally and kinetotically swimming individuals (the latter performed spinning movements). During hg, the animals were maintained in aquarium water containing alizarin-complexone (AC), a fluorescent calcium tracer. Densitometric measurements of AC uptake into inner ear otoliths (optical density of AC/μm 2) revealed that the kinetotic individuals had incorporated significantly more AC/calcium than the normally behaving fish. Since the amount of otolithic calcium can be taken as an approximation for otolith weight, the present results indicate that the otoliths of kinetotically swimming samples were heavier than those of the normally behaving larvae, thus exhibiting a higher absolute weight asymmetry of the otoliths between the right vs. the left side of the body. This supports an earlier concept according to which otolith (or statolith) asymmetry is the cause for kinetoses such as human static space sickness.

  19. Strontium and zinc concentrations in otoliths of common fish species in the northern Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Lill, J.-O., E-mail: jlill@abo.fi [Accelerator Laboratory, Turku PET Centre, Åbo Akademi University, Porthansgatan 3, FI-20500 Turku (Finland); Himberg, M. [Laboratory of Aquatic Pathobiology, Husö Biological Station, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Artillerigatan 6, FI-20520 Turku (Finland); Harju, L.; Ek, P. [Analytical Chemistry, Department of Chemical Engineering, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Lindroos, A. [Geology and Mineralogy, Department of Natural Sciences, Åbo Akademi University, Domkyrkotorget, FI-20500 Turku (Finland); Wiklund, T. [Laboratory of Aquatic Pathobiology, Husö Biological Station, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Artillerigatan 6, FI-20520 Turku (Finland); Gunnelius, K.; Smått, J.-H. [Physical Chemistry, Department of Natural Sciences, Åbo Akademi University, Porthansgatan 3, FI-20500 Turku (Finland); Heselius, S.-J. [Accelerator Laboratory, Turku PET Centre, Åbo Akademi University, Porthansgatan 3, FI-20500 Turku (Finland); Hägerstrand, H. [Laboratory of Aquatic Pathobiology, Husö Biological Station, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Artillerigatan 6, FI-20520 Turku (Finland)

    2014-01-01

    Otoliths of perch (Perca fluviatilis), pike (Esox lucius) and European whitefish (Coregonus lavaretus) caught at different locations in the northern Baltic Sea along the Finnish west coast and at some rivers and lakes were subjected to elemental analyses with particle induced X-ray emission and laser ablation inductively coupled plasma mass spectrometry. The strontium concentration in otoliths from whitefish (∼3300 μg/g) was 2–3 times higher than that of perch and pike (∼1400 μg/g), while within species the strontium concentration of otoliths from fish caught at different locations was in the same range. The strontium concentrations were lowest in fish from the lakes (∼450 μg/g). Whitefish otoliths contained more zinc (∼60 μg/g) than those of pike (∼30 μg/g), while the zinc concentration in perch otoliths were below the detection limit. No spatial intraspecies variations in zinc concentrations were observed. X-ray diffraction showed that the otoliths consisted of aragonite solely.

  20. Validating methods for measuring delta18O and delta13C in otoliths from freshwater fish.

    Science.gov (United States)

    Guiguer, K R R A; Drimmie, R; Power, M

    2003-01-01

    The ability of the phosphoric acid digestion technique to extract carbon dioxide from biogenic carbonates and reliably reproduce delta(18)O and delta(13)C signatures from standard reference materials (NBS-18, NBS-19) was tested and shown to produce accurate, unbiased measurements of non-biologic materials. The effects of roasting preparation methods commonly reported when analyzing biogenic carbonates were also tested in a series of experiments using reference standards and otoliths obtained from aquacultured Arctic charr and rainbow trout. Roasting had no effect on the isotope measurement of reference standards. No significant differences between mean oxygen isotope signatures from paired experiments with roasted and non-roasted fish otoliths were found. However, otolith oxygen isotope measurements were significantly enriched in comparison to rearing water-based measurements for both species. Agreement between expected isotopic equilibrium and measured otolith delta(18)O values varied as a function of roasting temperature and between species. Criteria for the selection of appropriate roasting temperatures are suggested and favour 350 degrees C in freshwater fish where unbiased estimates of average rearing water temperatures and known differences in rearing temperatures were obtained. Carbon isotopic disequilibria were observed for both species. A mixing model analysis established differences in the percentage of metabolically derived carbon in studied otoliths, with Arctic charr deriving a greater proportion of otolith delta(13)C from metabolism as a result of higher metabolic rates. PMID:12590395

  1. Magnetic materials in otoliths of bird and fish lagena and their function.

    Science.gov (United States)

    Harada, Y; Taniguchi, M; Namatame, H; Iida, A

    2001-07-01

    The mystery of the homing ability of pigeons has been the subject of much interest and it is widely believed that information from the earth's magnetic field may be involved. However, no specific magnetic sensory organ has yet been identified. The recent finding of magnetic materials in the lagenal otolith of fish and birds raises the possibility that these structures may be key elements in the elusive magnetic sensory system. For the elemental analysis of materials X-ray fluorescence using synchrotron radiation is one of the most powerful techniques available and was used in this study for analysis of the otoliths. By comparing the compositions of the three different kinds of otoliths among several species of sea fish and birds, we found that the saccular and utricular otoliths rarely contain detectable levels of iron but that iron is present in significant quantities in the lagenal otoliths of the birds. The lagenal otolith comprises tiny magnetic particles of low inertia that are displaced by imposed magnetic fields, providing the animal with geomagnetic sensory input, from which the brain would infer navigational information. PMID:11583391

  2. Integrating microsatellite DNA markers and otolith geochemistry to assess population structure of European hake (Merluccius merluccius)

    Science.gov (United States)

    Tanner, Susanne E.; Pérez, Montse; Presa, Pablo; Thorrold, Simon R.; Cabral, Henrique N.

    2014-04-01

    Population structure and natal origins of European hake were investigated using microsatellite DNA markers and otolith geochemistry data. Five microsatellites were sequenced and otolith core geochemical composition was determined from age-1 hake collected in the northeast Atlantic Ocean and the Mediterranean Sea. Microsatellites provided evidence of a major genetic split in the vicinity of the Strait of Gibraltar, separating the Atlantic and the Mediterranean populations, with the exception of the Gulf of Cádiz. Based on classification models using otolith core geochemical values, individual natal origins were identified, although with an increased error rate. Coupling genotype and otolith data increased the classification accuracy of individuals to their potential natal origins while providing evidence of movement between the northern and southern stock units in the Atlantic Ocean. Information obtained by the two natural markers on population structure of European hake was complementary as the two markers act at different spatio-temporal scales. Otolith geochemistry provides information over an ecological time frame and on a fine spatial scale, while microsatellite DNA markers report on gene flow over evolutionary time scales and therefore act on a broader spatio-temporal resolution. Thus, this study confirmed the value of otolith geochemistry to complement the assessment of early life stage dispersal in populations with high gene flow and low genetic divergence.

  3. Strontium and zinc concentrations in otoliths of common fish species in the northern Baltic Sea

    International Nuclear Information System (INIS)

    Otoliths of perch (Perca fluviatilis), pike (Esox lucius) and European whitefish (Coregonus lavaretus) caught at different locations in the northern Baltic Sea along the Finnish west coast and at some rivers and lakes were subjected to elemental analyses with particle induced X-ray emission and laser ablation inductively coupled plasma mass spectrometry. The strontium concentration in otoliths from whitefish (∼3300 μg/g) was 2–3 times higher than that of perch and pike (∼1400 μg/g), while within species the strontium concentration of otoliths from fish caught at different locations was in the same range. The strontium concentrations were lowest in fish from the lakes (∼450 μg/g). Whitefish otoliths contained more zinc (∼60 μg/g) than those of pike (∼30 μg/g), while the zinc concentration in perch otoliths were below the detection limit. No spatial intraspecies variations in zinc concentrations were observed. X-ray diffraction showed that the otoliths consisted of aragonite solely

  4. Comparative Transduction Mechanisms of Vestibular Otolith Hair Cells

    Science.gov (United States)

    Baird, Richard A.

    1994-01-01

    Hair cells in the bullfrog vestibular otolith organs regenerate following aminoglycoside ototoxicity. Hair cells in these organs are differentially sensitive to gentamicin, with saccular hair cells and hair cells in the utricular striola being damaged at lower gentamicin concentrations than hair cells in the utricular extrastriola. Regenerating hair cells in these organs have short hair bundles and can be classified into a number of phenotypes using the same morphological criteria used to identify their mature counterparts. Our studies suggest that some supporting cells can convert, or transdifferentiate,into hair cells without an intervening cell division. By stimulating these processes in humans, clinicians may be able to alleviate human deafness and peripheral vestibular disorders by regenerating and replacing lost hair cells. In vivo and in vitro studies were done on cell proliferation and hair cell regeneration.

  5. Reliable micro-measurement of strontium is the key to cracking the life-history code in the fish otolith

    Science.gov (United States)

    Markwitz, A.; Grambole, D.; Herrmann, F.; Trompetter, W. J.; Dioses, T.; Gauldie, R. W.

    2000-05-01

    The fish otolith is a calcium carbonate (usually aragonite) crystal that grows continuously by accretion over the life of the fish and unlike bone is not continuously re-metabolised. Consequently, the otolith has long been regarded as a potential store of information about the life history of an individual fish, and this information is encoded in the deposition pattern of trace elements in the otolith. The code has been difficult to crack. However, recent developments have show that: (1) Sr is one of the few non-mobile trace elements in the otolith; and (2) the pattern of Sr deposition summarises the effects of environment changes that affect the growth rate of the otolith crystal. The remaining difficulties in cracking the chemical code in the otolith have hinged about making reliable micro-measurements of the stable Sr content at spatial resolutions of 10 μm or less; this interval represents about 4-6 days of otolith growth in most species of fish. This paper describes high beam resolution 2 μm linear measurements, and 6 μm square measurements over narrow windows of about 300 μm square, and links these micro-measures to macro-measures of 2D maps of the entire surface of sections of otoliths up to 5 mm square at beam resolutions of 25 μm square. The otoliths used in this study are from the Jurel, or Peruvian Jack mackerel, Trachurus murphyi (Carangidae: Teleostei).

  6. Reliable micro-measurement of strontium is the key to cracking the life-history code in the fish otolith

    Energy Technology Data Exchange (ETDEWEB)

    Markwitz, A. E-mail: a.markwitz@gns.cri.nz; Grambole, D.; Herrmann, F.; Trompetter, W.J.; Dioses, T.; Gauldie, R.W

    2000-05-01

    The fish otolith is a calcium carbonate (usually aragonite) crystal that grows continuously by accretion over the life of the fish and unlike bone is not continuously re-metabolised. Consequently, the otolith has long been regarded as a potential store of information about the life history of an individual fish, and this information is encoded in the deposition pattern of trace elements in the otolith. The code has been difficult to crack. However, recent developments have show that: (1) Sr is one of the few non-mobile trace elements in the otolith; and (2) the pattern of Sr deposition summarises the effects of environment changes that affect the growth rate of the otolith crystal. The remaining difficulties in cracking the chemical code in the otolith have hinged about making reliable micro-measurements of the stable Sr content at spatial resolutions of 10 {mu}m or less; this interval represents about 4-6 days of otolith growth in most species of fish. This paper describes high beam resolution 2 {mu}m linear measurements, and 6 {mu}m square measurements over narrow windows of about 300 {mu}m square, and links these micro-measures to macro-measures of 2D maps of the entire surface of sections of otoliths up to 5 mm square at beam resolutions of 25 {mu}m square. The otoliths used in this study are from the Jurel, or Peruvian Jack mackerel, Trachurus murphyi (Carangidae: Teleostei)

  7. Preparation techniques alter the mineral and organic fractions of fish otoliths: insights using Raman micro-spectrometry.

    Science.gov (United States)

    Jolivet, Aurélie; Fablet, Ronan; Bardeau, Jean-François; de Pontual, Hélène

    2013-05-01

    The high spatial resolution analysis of the mineral and organic composition of otoliths using Raman micro-spectrometry involves rigorous protocols for sample preparation previously established for microchemistry and trace elements analyses. These protocols often include otolith embedding in chemically neutral resin (i.e., resins which do not contain, in detectable concentration, elements usually sought in the otoliths). Such embedding may however induce organic contamination. In this paper, Raman micro-spectrometry reveals the presence of organic contamination onto the surface obtained from the use of epoxy resin, specifically Araldite. This contamination level varies depending on otolith structures. Core and checks, known as structural discontinuities, exhibit the most important level of contaminations. Our results suggest that otolith embedding with resin affects the organic matrix of the otolith, probably through an infiltration of the resin in the crystalline structure. The interpretation of chemical otolith signatures, especially Raman otolith signatures, and stable isotope analyses should then be revised in light of these results. In this respect, we propose a method for the correction of Raman otolith signatures for contamination effects. PMID:23508582

  8. FLUCTUATING ASYMMETRY IN THE OTOLITH WIDTH OF Carangoides caeruleopinnatus (CARANGIDAE COLLECTED FROM MUSCAT CITY COAST ON THE SEA OF OMAN

    Directory of Open Access Journals (Sweden)

    Dawood Al-Mamari

    2012-10-01

    Full Text Available The fluctuating asymmetry in two otolith dimensions, the length and width of adult teleost Carangoides caeruleopinnatus were calculated. The highest asymmetry value was observed in the otolith width. The fish length groups 201-210 and 281-290 mm showed the lowest and the highest value of asymmetry respectively. In addition, few fish length groups have shown zero value for otolith size asymmetry. Different pollutants and their presence in the area appeared to be one of the reasons that cause the asymmetry in this species. A trend of increase in the asymmetry values with the fish length was noticed for the otolith length and width.

  9. OTOLITH MASS ASYMMETRY IN CARANGOIDES CAERULEPINNATUS (RÜPPELL, 1830 (FAMILY: CARANGIDAE COLLECTED FROM THE SEA OF OMAN

    Directory of Open Access Journals (Sweden)

    Laith Jawad

    2013-04-01

    Full Text Available The sagittae mass asymmetry was studied in the teleost Carangoides caeruleopinnatus. The value of the asymmetry was calculated as the difference between the mass of the right and left paired otoliths, divided by average otolith mass. The results show that the absolute value of X in C. caeruleopinnatus does not depend on fish length and otolith growth rate, as it does in other symmetrical fish species. However, the absolute value of otolith mass difference increases with the fish length. The value of x falls between -0.2 and +0.2.

  10. Reliable micro-measurement of strontium is the key to cracking the life-history code in the fish otolith

    International Nuclear Information System (INIS)

    The fish otolith is a calcium carbonate (usually aragonite) crystal that grows continuously by accretion over the life of the fish and unlike bone is not continuously re-metabolised. Consequently, the otolith has long been regarded as a potential store of information about the life history of an individual fish, and this information is encoded in the deposition pattern of trace elements in the otolith. The code has been difficult to crack. However, recent developments have show that: (1) Sr is one of the few non-mobile trace elements in the otolith; and (2) the pattern of Sr deposition summarises the effects of environment changes that affect the growth rate of the otolith crystal. The remaining difficulties in cracking the chemical code in the otolith have hinged about making reliable micro-measurements of the stable Sr content at spatial resolutions of 10 μm or less; this interval represents about 4-6 days of otolith growth in most species of fish. This paper describes high beam resolution 2 μm linear measurements, and 6 μm square measurements over narrow windows of about 300 μm square, and links these micro-measures to macro-measures of 2D maps of the entire surface of sections of otoliths up to 5 mm square at beam resolutions of 25 μm square. The otoliths used in this study are from the Jurel, or Peruvian Jack mackerel, Trachurus murphyi (Carangidae: Teleostei)

  11. Enhancement of Otolith Specific Ocular Responses Using Vestibular Stochastic Resonance

    Science.gov (United States)

    Fiedler, Matthew; De Dios, Yiri E.; Esteves, Julie; Galvan, Raquel; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar

    2011-01-01

    Introduction: Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Our goal is to develop a countermeasure based on vestibular stochastic resonance (SR) that could improve central interpretation of vestibular input and mitigate these risks. SR is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. Methods: Eye movement data were collected from 10 subjects during variable radius centrifugation (VRC). Subjects performed 11 trials of VRC that provided equivalent tilt stimuli from otolith and other graviceptor input without the normal concordant canal cues. Bipolar stochastic electrical stimulation, in the range of 0-1500 microamperes, was applied to the vestibular system using a constant current stimulator through electrodes placed over the mastoid process behind the ears. In the VRC paradigm, subjects were accelerated to 216 deg./s. After the subjects no longer sensed rotation, the chair oscillated along a track at 0.1 Hz to provide tilt stimuli of 10 deg. Eye movements were recorded for 6 cycles while subjects fixated on a target in darkness. Ocular counter roll (OCR) movement was calculated from the eye movement data during periods of chair oscillations. Results: Preliminary analysis of the data revealed that 9 of 10 subjects showed an average increase of 28% in the magnitude of OCR responses to the equivalent tilt stimuli while experiencing vestibular SR. The signal amplitude at which performance was maximized was in the range of 100-900 microamperes. Discussion: These results indicate that stochastic electrical stimulation of the vestibular system can improve otolith specific responses. This will have a

  12. The role of hair cells, cilia and ciliary motility in otolith formation in the zebrafish otic vesicle.

    Science.gov (United States)

    Stooke-Vaughan, Georgina A; Huang, Peng; Hammond, Katherine L; Schier, Alexander F; Whitfield, Tanya T

    2012-05-01

    Otoliths are biomineralised structures required for the sensation of gravity, linear acceleration and sound in the zebrafish ear. Otolith precursor particles, initially distributed throughout the otic vesicle lumen, become tethered to the tips of hair cell kinocilia (tether cilia) at the otic vesicle poles, forming two otoliths. We have used high-speed video microscopy to investigate the role of cilia and ciliary motility in otolith formation. In wild-type ears, groups of motile cilia are present at the otic vesicle poles, surrounding the immotile tether cilia. A few motile cilia are also found on the medial wall, but most cilia (92-98%) in the otic vesicle are immotile. In mutants with defective cilia (iguana) or ciliary motility (lrrc50), otoliths are frequently ectopic, untethered or fused. Nevertheless, neither cilia nor ciliary motility are absolutely required for otolith tethering: a mutant that lacks cilia completely (MZovl) is still capable of tethering otoliths at the otic vesicle poles. In embryos with attenuated Notch signalling [mindbomb mutant or Su(H) morphant], supernumerary hair cells develop and otolith precursor particles bind to the tips of all kinocilia, or bind directly to the hair cells' apical surface if cilia are absent [MZovl injected with a Su(H)1+2 morpholino]. However, if the first hair cells are missing (atoh1b morphant), otolith formation is severely disrupted and delayed. Our data support a model in which hair cells produce an otolith precursor-binding factor, normally localised to tether cell kinocilia. We also show that embryonic movement plays a minor role in the formation of normal otoliths. PMID:22461562

  13. Carbon isotopes in otolith amino acids identify residency of juvenile snapper (Family: Lutjanidae) in coastal nurseries

    KAUST Repository

    McMahon, Kelton

    2011-08-26

    This study explored the potential for otolith geochemistry in snapper (Family: Lutjanidae) to identify residency in juvenile nursery habitats with distinctive carbon isotope values. Conventional bulk otolith and muscle stable isotope analyses (SIA) and essential amino acid (AA) SIA were conducted on snapper collected from seagrass beds, mangroves, and coral reefs in the Red Sea, Caribbean Sea, and Pacific coast of Panama. While bulk stable isotope values in otoliths showed regional differences, they failed to distinguish nursery residence on local scales. Essential AA δ13C values in otoliths, on the other hand, varied as a function of habitat type and provided a better tracer of residence in different juvenile nursery habitats than conventional bulk otolith SIA alone. A strong linear relationship was found between paired otolith and muscle essential AA δ13C values regardless of species, geographic region, or habitat type, indicating that otolith AAs recorded the same dietary information as muscle AAs. Juvenile snapper in the Red Sea sheltered in mangroves but fed in seagrass beds, while snapper from the Caribbean Sea and Pacific coast of Panama showed greater reliance on mangrove-derived carbon. Furthermore, compound-specific SIA revealed that microbially recycled detrital carbon, not water-column-based new phytoplankton carbon, was the primary carbon source supporting snapper production on coastal reefs of the Red Sea. This study presented robust tracers of juvenile nursery residence that will be crucial for reconstructing ontogenetic migration patterns of fishes among coastal wetlands and coral reefs. This information is key to determining the importance of nursery habitats to coral reef fish populations and will provide valuable scientific support for the design of networked marine-protected areas. © 2011 Springer-Verlag.

  14. Near-reef elemental signals in the otoliths of settling Pomacentrus amboinensis (Pomacentridae)

    Science.gov (United States)

    Sih, Tiffany L.; Kingsford, Michael J.

    2016-03-01

    Settlement is a key life history transition for coral reef fishes, and how long a fish spends close to a reef prior to settlement is poorly understood. We used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and otolith microstructure analysis (daily increments and settlement marks) to determine the length of time larval fish spend near a reef prior to settlement. The otoliths of Pomacentrus amboinensis collected from four neighbouring reefs in the southern Great Barrier Reef showed clear and consistent differences in their elemental signatures prior to and following settlement. Elevated Ba:Ca near settlement and post-settlement was found in fish from all four reefs. However, there was individual variation in elemental profiles, with an increased otolith Ba-to-Ca ratio (near-reef signature) at settlement in 33 % of fish, and up to 8 d prior to settlement in others. Increment widths, often used as a proxy for growth, decreased approaching the settlement mark for all fish, providing further evidence for a "search phase" in larvae. We demonstrated experimentally that otoliths of fish kept in reefal or inter-reefal waters had different elemental chemistry. There were differences in the elemental composition of water samples within the study area, but no consistent trends with distance from reefs. There was poor discrimination of multi-element signatures among fish from different reefs during their pre-settlement phases. However, discrimination improved in the settlement and post-settlement phases of otoliths, indicating that reef waters and perhaps stage of ontogeny affected otolith chemistry. This study demonstrated clear near-reef elemental signatures in fish around settlement. We suggest these differences are due to a combination of water chemistry and physiological influences (e.g., growth). Combining LA-ICP-MS with otolith microstructure analysis can provide high-resolution information on the early life history of reef fishes. Further, a

  15. The Regional Patterns of Chemical Composition in the Otolith Core of Larval Fish

    Science.gov (United States)

    Chang, M. Y.; Geffen, A. J.; Nash, R. D. M.; Clemmesen, C.

    2012-04-01

    The elemental composition of fish otoliths can record the environmental information because once a trace element is deposited in the otolith; it presents a permanent record of the environmental conditions experienced by the fish at a particular time. The elemental signature of the otolith nucleus, the area lying within the first annual growth ring, is likely to be characteristic of the nursery areas of the species, and could be used as biological tracer for tracking origin and dispersal. However, ocean acidification may alter otolith growth and element incorporation, and it is important to establish baseline information about the sources of variation - both biotic and abiotic. The objectives of this study, as part of the wider CalMarO network, is to examine the regional differences in the otolith cores of selected fish species, contrast these differences with those measured between these same species in areas where their larvae co-exist and to find out the maternal effect to the chemical composition during the first forming of otoliths. The laboratory and field experiments were included to produce otolith material reflecting the maternal and regional patterns. Otolith composition was measured using laser-ablation ICPMS. For clarifying the regional patterns, juveniles from six locations and seven spawning groups along the west of the British Isles and larvae from the North Sea were sampled to distinguish the origin of spawning herring. There are three main nursery-ground groups, the Irish Sea, Scottish sea lochs and the Minch, contributing to the spawning herring in the west of the British Isles according to the otolith elemental composition data. However, the spawning origin of the North Sea herring larvae was still unclear. The otolith concentrations of Li, Na, Mg, Mn, Cu, Ru and Sr were significantly different among nursery-ground populations. Together with length-at-age data, at least two nursery-ground groups contributed to each spawning population. The

  16. Sites of calcium uptake of fish otoliths correspond with macular regions rich of carbonic anhydrase

    Science.gov (United States)

    Beier, M.; Anken, R.; Hilbig, R.

    2006-01-01

    Based on pharmacological data, it has been suggested that the enzyme carbonic anhydrase (CAH) plays a prominent role in the mineralization of fish otoliths. To directly test this proposal, the topographical distribution of CAH was histochemically analyzed in the utricular and saccular maculae of larval cichlid fish Oreochromis mossambicus. Further investigations were focussed on the sites of otolithic calcium uptake using the fluorescent calcium tracer alizarin-complexone (AC). Both in the utricle and the saccule, CAH-reactivity was prominent in regions on both sides of the sensory macula (centrifugal (cf) and centripetal (cp) areas), which reportedly contain ionocytes, specialized cells regulating the ionic composition of the endolymph. (The terms centrifugal and centripetal were chosen instead of lateral and medial, because the saccule is positioned perpendicular to the utricle; “lateral” and “medial” thus do not allow an unambiguous allocation of the respective regions.) In the saccule, the size of cf and cp did not differ from each other, whereas, in the utricle, cp was considerably larger as compared to cf (CAH-reactivity per μm2 was nearly identical in both areas of both endorgans). AC-incubation resulted in a fluorescent band on the proximal surface of the otoliths (this surface lies next to the sensory epithelium). In saccular otoliths (sagittae), the area of the band did not differ between centrifugal and centripetal otolith regions, whereas in the utricular otoliths (lapilli), the area of the centripetal AC-band was larger in size as compared to the centrifugal one (AC-fluorescence per μm2 did not differ between the areas analyzed in both types of otoliths). These results strongly suggest that calcium/carbonate uptake of otoliths takes place especially in those regions of their proximal face which are located adjacent to CAH-rich areas of the macular epithelium. It is thus concluded that CAH is directly involved in otolith calcification. The

  17. Effects of sex, stock, and environment on the shape of known-age Atlantic cod ( Gadus morhua ) otoliths

    DEFF Research Database (Denmark)

    Cardinale, M.; Doering-Arjes, P.; Kastowsky, M.; Mosegaard, Henrik

    2004-01-01

    temperature and diet regime) on otolith shape and morphometrics. Using otolith shape, cod individuals were significantly separated into Bank and Plateau stocks. Total classification success was between 79% and 85% between stocks and between 85% and 96% between environments for the different age classes. The...

  18. A new method to reconstruct fish diet and movement patterns from δ 13 C values in otolith amino acids

    KAUST Repository

    McMahon, Kelton W.

    2011-08-01

    Fish ecologists have used geochemical values in otoliths to examine habitat use, migration, and population connectivity for decades. However, it remains difficult to determine an unambiguous dietary δ 13C signature from bulk analysis of otolith. Studies to date have focused on the aragonite component of otoliths with less attention paid to the organic fraction. We describe the application of compound-specific stable isotope analysis (SIA) to analyze amino acid (AA) δ 13C values from small amounts (<1 mg) of otolith powder. We examined δ 13C values of otolith and muscle AAs from a reef-associated snapper (Lutjanus ehrenbergii (Peters, 1869)) collected along a carbon isotope gradient (isoscape) from seagrass beds to coral reefs. Carbon isotope values in otolith and muscle samples were highly correlated within and among coastal habitats. Moreover, δ 13C values of otolith AAs provided a purely dietary record that avoided dilution from dissolved inorganic carbon. Otolith AAs served as a robust tracer of δ 13C values at the base of the food web, making compound-specific SIA a powerful tool for dietary reconstructions and tracking the movement of fishes across isoscapes.

  19. Determination of interannual variability in early life history of Pleuronectes platessa (L. using otolith microstructure

    Directory of Open Access Journals (Sweden)

    Joana Filipa Moreira De Sousa

    2015-11-01

    Plaice 0-group juveniles were sampled from an inshore nursery ground (Valosen, Bodø, Norway between 2005 and 2006, and otolith microstructure was examined. For that, sagitta otoliths were mounted in microscope slides using a thermoplastic cement (crystalbond™, with the concave side down. Otoliths were then hand-ground to the otolith core using sandpaper (3, 1 µm and examined under transmitted light in a microscope linked to an image analysis system. This technique exposed the daily increments in the otoliths that once counted allowed to determine hatch dates, larval duration, settlement dates and total age of the fish. A one-month difference in hatching and settlement times was found between 2005 and 2006, occurring later in 2006, but larval stage duration was similar in both years. Compared to other areas located further south, hatching and settlement occurred earlier showing a latitudinal cline. Interannual differences in growth were also detected, with higher rates in 2006 which could be related to warmer temperatures during plaice first summer of life. Yet, growth rates were similar to other locations across the species distributional range which suggest the existence of a countergradient growth compensation mechanism in this northern population. This means that despite the lower environmental temperature at high latitudes, other factors such as productivity and photoperiod may play a key role during the growing season. Nevertheless, further work needs to be done in order to fully understand temporal variation in plaice early life dynamics.

  20. On the role of carbonic anhydrase in the early phase of fish otolith mineralization

    Science.gov (United States)

    Beier, M.; Anken, R.

    2006-01-01

    The first step in the formation of fish otoliths, calcified structures which are responsible for the internalization of gravitational information, is based on the action of so-called Tether- (T-) cells. These T-cells appear during the very early development of the inner ear and persist only a few hours. They are characterized by a kinocilium, which is in contrast to the kinocilium of the later developing sensory hair cells not mechanosensory, but binds seeding particles containing glycogen, thereby localizing otolith formation (otolith seeding). Beating cilia distributed throughout the ear agitate seeding particles, thereby inhibiting premature agglutination. In the later development, a protein matrix is formed and mineralization/crystallization takes place. Since the enzyme carbonic anhydrase (CAH) plays a prominent role in otolith mineralization (it provides carbonate for CaCO3 precipitation), we were prompted to investigate histochemically using larval cichlid fish (Oreochromis mossambicus), whether CAH might be present as early as T-cells. Indeed, CAH was present in T-cells with prominent amounts of reaction product being located along the kinocilia and around the seeding particles. These results strongly indicate that kinocilia of T-cells act as structural guides for CAH/bicarbonate transportation towards the early otoliths’ calcification sites. Besides its role in calcification, CAH in the very early stage of otolith seeding may moreover aid in the accretion process of the precursor particles.

  1. Use of an otolith-deficient mutant in studies of fish behavior in microgravity

    Science.gov (United States)

    Ijiri, K.; Mizuno, R.; Eguchi, H.

    2003-10-01

    The mutant strain ( ha) of medaka ( Oryzias latipes) lack utricular otoliths as fry, and some never form otoliths for life. The cross (Fl generation) between the strain having good eyesight and another strain having ordinary eyesight augmented visual acuity of the Fl generation. Crossing the good eyesight strain and ha mutant produced fish having good eyesight and less sensitivity to gravity in the F2 population. Their tolerance to microgravity was tested by parabolic flight using an airplane. The fish exhibited less looping and no differences in degree of looping between light and dark conditions, suggesting that loss of eyesight (in darkness) is not a direct cause for looping behavior in microgravity. The ha embryos could not form utricular otoliths. They did form saccular otoliths, but with a delay. Fry of the mutant fish lacking the utricular otoliths are highly dependent on light upon hatching and exhibit a perfect dorsal-light response (DLR). As they grow, they eventually shift from being light-dependent to being gravity-dependent. Continuous treatment of the fry with altered light direction suppressed this shift to gravity dependence. Being less dependent on gravity, these fish can serve as models in studying the differences expected for the vestibular system of fish reared in microgravity. When these fish were exposed to microgravity (parabolic flights) of an airplane, they spent far less time looping than fish reared in an ordinary light regimen.

  2. Endolymphatic calcium supply for fish otolith growth takes place via the proximal portion of the otocyst.

    Science.gov (United States)

    Ibsch, M; Anken, R; Beier, M; Rahmann, H

    2004-09-01

    The presence of calcium within the utricle of larval cichlid fish Oreochromis mossambicus was analysed by means of energy-filtering transmission electron microscopy. Electron-spectroscopic imaging and electron energy loss spectra revealed discrete calcium precipitations that were more numerous in the proximal endolymph than in the distal endolymph, clearly indicating a decreasing proximo-distal gradient. This decreasing proximo-distal gradient was also present within the proximal endolymph between the sensory epithelium and the otolith. Further calcium particles covered the peripheral proteinaceous layer of the otolith. They were especially pronounced at the proximal surface of the otolith indicating that otolithic calcium incorporation takes place here. Other calcium precipitates accumulated at the macular junctions clearly supporting an earlier assumption according to which the endolymph is supplied with calcium via a paracellular pathway. The present results clearly show that the apical region of the macular epithelium is involved in the release of calcium and that the calcium supply of the otoliths takes place via the proximal endolymph. PMID:15300493

  3. High prevalence of vaterite in sagittal otoliths causes hearing impairment in farmed fish.

    Science.gov (United States)

    Reimer, T; Dempster, T; Warren-Myers, F; Jensen, A J; Swearer, S E

    2016-01-01

    The rapid growth of aquaculture raises questions about the welfare status of mass-produced species. Sagittal otoliths are primary hearing structures in the inner ear of all teleost (bony) fishes and are normally composed of aragonite, though abnormal vaterite replacement is sometimes seen in the wild. We provide the first widespread evaluation of the prevalence of vaterite in otoliths, showing that farmed fish have levels of vaterite replacement over 10 times higher than wild fish, regardless of species. We confirm this observation with extensive sampling of wild and farmed Atlantic salmon in Norway, the world's largest producer, and verify that vateritic otoliths are common in farmed salmon worldwide. Using a mechanistic model of otolith oscillation in response to sound, we demonstrate that average levels of vaterite replacement result in a 28-50% loss of otolith functionality across most of a salmonid's known hearing range and throughout its life cycle. The underlying cause(s) of vaterite formation remain unknown, but the prevalence of hearing impairment in farmed fish has important implications for animal welfare, the survival of escapees and their effects on wild populations, and the efficacy of restocking programs based on captive-bred fish. PMID:27121086

  4. Angular oscillation of solid scatterers in response to progressive planar acoustic waves: do fish otoliths rock?

    Science.gov (United States)

    Krysl, Petr; Hawkins, Anthony D; Schilt, Carl; Cranford, Ted W

    2012-01-01

    Fish can sense a wide variety of sounds by means of the otolith organs of the inner ear. Among the incompletely understood components of this process are the patterns of movement of the otoliths vis-à-vis fish head or whole-body movement. How complex are the motions? How does the otolith organ respond to sounds from different directions and frequencies? In the present work we examine the responses of a dense rigid scatterer (representing the otolith) suspended in an acoustic fluid to low-frequency planar progressive acoustic waves. A simple mechanical model, which predicts both translational and angular oscillation, is formulated. The responses of simple shapes (sphere and hemisphere) are analyzed with an acoustic finite element model. The hemispherical scatterer is found to oscillate both in the direction of the propagation of the progressive waves and also in the plane of the wavefront as a result of angular motion. The models predict that this characteristic will be shared by other irregularly-shaped scatterers, including fish otoliths, which could provide the fish hearing mechanisms with an additional component of oscillation and therefore one more source of acoustical cues. PMID:22912710

  5. Validating the use of embryonic fish otoliths as recorders of sublethal exposure to copper in estuarine sediments.

    Science.gov (United States)

    Barbee, Nicole C; Greig, Alan; Swearer, Stephen E

    2013-07-01

    In this study we explore the use of fish otoliths ('earbones') as a tool for detecting exposure to heavy metals in sediments. Because otoliths are metabolically inert and incorporate chemical impurities during growth, they can potentially provide a more permanent record of pollutant exposure history in aquatic environments than soft tissues. To validate this technique we cultured embryos of a native Australian fish, the common Galaxias (Galaxias maculatus), in the laboratory on sediments spiked with copper in a concentration gradient. Our aims were to test whether exposure to copper contaminated sediments is recorded in the otoliths of embryos and determine over what range in concentrations we can detect differences in exposure. We found elevated copper levels in otoliths of embryos exposed to high copper concentrations in sediments, suggesting that otoliths can be used as a tool to track a history of exposure to elevated copper levels in the environment. PMID:23628888

  6. The effect of otolith malformation on behavior and cortisol levels in juvenile red drum fish (Sciaenops ocellatus).

    Science.gov (United States)

    Browning, Zoe S; Wilkes, Allison A; Moore, Erica J; Lancon, Trevor W; Clubb, Fred J

    2012-08-01

    Captive-raised red drum fish were observed with phenotypic abnormalities, including deformities of the spine, jaw, and cephalic region, that were consistent with vitamin C deficiency during the larval stage. In light of their visible exterior skeletal abnormalities, we suspected that the affected fish would also have abnormal otoliths. Otoliths are dense calcareous structures that function in fish hearing. We hypothesized that abnormal fish would have irregular otoliths that would alter behavior and cortisol levels as compared with those of phenotypically normal fish. The normal and abnormal fish had statistically significant differences in behavior, cortisol levels, and otolith volume and density. MicroCT assessment of abnormal fish revealed operculum abnormalities, malocclusions, and several types of otolith malformations. Therefore, the affected fish had not only an abnormal skeletal appearance but also significantly abnormal behavior and cortisol responses. PMID:23043776

  7. Micro-PIXE study of whole otolith of Anguilla japonica at elver stage

    Science.gov (United States)

    Zheng, Y.; Guo, H.; Wei, K.; Tang, W.; Satoh, T.; Ohkubo, T.; Yamazaki, A.; Takano, K.; Kamiya, T.; Shen, H.; Yang, M.; Mi, Y.

    2010-06-01

    Strontium and calcium contents, within the otolith of Anguilla japonica, were measured by external micro-PIXE. According to the measured metamorphic checks, each otolith was divided into three stages. Comparing with the Sr:Ca ratios in stage 2, the ratios in stage 1 had two different trends. Among these fish, it may reflect their maternal condition was not the same. The ratios in stage 3 which was corresponding to the estuarine habitat were smaller than that in any other stage which was corresponding to the ocean habitat in each otolith. Suggested by our results, the eels from the spawning site may separate into two groups when they are near to the south of Taiwan, and then move to the different estuaries in China. It could be proposed that, in general, the migration direction is from south to north along the east coast in China.

  8. PIXE analyses of polished otoliths for identification of anadromous whitefish in the Baltic Sea

    Science.gov (United States)

    Lill, Jan-Olof; Heimbrand, Yvette; Slotte, Joakim; Himberg, Mikael; Florin, Ann-Britt; Hägerstrand, Henry

    2015-11-01

    In this work we describe an application of particle-induced X-ray emission (PIXE) to the elemental analysis of polished otoliths of whitefish. Two spots on polished otoliths were irradiated; one spot in the core region of the otolith and another one close to the edge. The irradiations were performed in air with a collimated 0.5 mm proton beam. The ratio of the strontium concentrations in the two spots was used to distinguish between different ecotypes (river, sea, lake) of whitefish. Criteria on the ratios were suggested for identification of the whitefish forms. The results were compared to results of μ-beam PIXE scans as well as multi-point scans with the 0.5 mm proton beam. The measuring set-up and the results are discussed.

  9. Application of micro-PIXE to fish life history analyses: trace element analysis of otoliths

    International Nuclear Information System (INIS)

    Otoliths are biogenic, carbonate concretions which form part of the hearing/balance system in fishes. The radial growth of otoliths and the variation of trace elements along the radius appear to capture important aspects of fishes' environmental history. At the Lund Nuclear Microprobe Laboratory, we have begun to use Proton-Induced X-ray Emission spectroscopy (PIXE) for micro-elemental analysis of otoliths. The experimental procedure is discussed and a number of examples of what can be investigated are presented. In particular, movement of diadromous species (eel, menhaden, and anadromous brown trout) can be detected between fresh and brackish water by Sr/Ca ratio. This technique has also been used to identify fish that were raised in freshwater hatcheries and then released to brackish water (pike-perch example)

  10. Using otolith microstructure to analyse growth of juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.; Böttcher, U.

    2003-01-01

    relationship between fish and otolith size were found to change at settling, with an increase of fish size in relation to otolith size after settling. This change was more pronounced on the slope compared to the top of the bank. The timing of first settling at the 2 localities did not differ with respect to......Pelagic and demersal juvenile Baltic cod Gadus morhua L. were collected on the slope and the top of Rønne bank in the Baltic Sea during 2 cruises in November and December 1998. The growth, age at settling and vertical migration pattern were studied by otolith microstructure analysis. The...... fish age. At both localities, fish that hatched early in the season spent a shorter time in the pelagic stage than late-hatched fish. However, significant differences in growth rate during the pelagic stage were observed, where fish captured on the slope grew faster. On the bank, individuals with fast...

  11. Slow growth did not decouple the otolith size-fish size relationship in striped bass

    Science.gov (United States)

    Dickey, C.L.; Isely, J.J.; Tomasso, J.R.

    1997-01-01

    Eight-day-old striped bass Morone saxatilis (6.17-6.22 mm, total length) were fed twice daily at three feeding rates to produce three growth rates. Fish were sampled once per week for 4 weeks to determine total length and otolith radius. Feed ration treatments resulted in discrete size-classes of striped bass after 4 weeks with a 27% difference in mean length between the low and high feed ration treatments. No significant differences in slope or intercept for the regression of fish length on otolith radius were observed among treatments, suggesting that slow growth alone may not be sufficient to result in decoupling of the otolith size-fish size relationship in striped bass.

  12. Application of micro-PIXE to fish life history analyses: trace element analysis of otoliths

    Science.gov (United States)

    Elfman, M.; Limburg, K. E.; Kristiansson, P.; Malmqvist, K.; Pallon, J.

    1999-04-01

    Otoliths are biogenic, carbonate concretions which form part of the hearing/balance system in fishes. The radial growth of otoliths and the variation of trace elements along the radius appear to capture important aspects of fishes' environmental history. At the Lund Nuclear Microprobe Laboratory, we have begun to use Proton-Induced X-ray Emission spectroscopy (PIXE) for micro-elemental analysis of otoliths. The experimental procedure is discussed and a number of examples of what can be investigated are presented. In particular, movement of diadromous species (eel, menhaden, and anadromous brown trout) can be detected between fresh and brackish water by Sr/Ca ratio. This technique has also been used to identify fish that were raised in freshwater hatcheries and then released to brackish water (pike-perch example).

  13. Application of micro-PIXE to fish life history analyses: trace element analysis of otoliths

    Energy Technology Data Exchange (ETDEWEB)

    Elfman, M. E-mail: mikael.elfman@nuclear.lu.se; Limburg, K.E.; Kristiansson, P.; Malmqvist, K.; Pallon, J

    1999-04-02

    Otoliths are biogenic, carbonate concretions which form part of the hearing/balance system in fishes. The radial growth of otoliths and the variation of trace elements along the radius appear to capture important aspects of fishes' environmental history. At the Lund Nuclear Microprobe Laboratory, we have begun to use Proton-Induced X-ray Emission spectroscopy (PIXE) for micro-elemental analysis of otoliths. The experimental procedure is discussed and a number of examples of what can be investigated are presented. In particular, movement of diadromous species (eel, menhaden, and anadromous brown trout) can be detected between fresh and brackish water by Sr/Ca ratio. This technique has also been used to identify fish that were raised in freshwater hatcheries and then released to brackish water (pike-perch example)

  14. Micro-PIXE study of whole otolith of Anguilla japonica at elver stage

    International Nuclear Information System (INIS)

    Strontium and calcium contents, within the otolith of Anguilla japonica, were measured by external micro-PIXE. According to the measured metamorphic checks, each otolith was divided into three stages. Comparing with the Sr:Ca ratios in stage 2, the ratios in stage 1 had two different trends. Among these fish, it may reflect their maternal condition was not the same. The ratios in stage 3 which was corresponding to the estuarine habitat were smaller than that in any other stage which was corresponding to the ocean habitat in each otolith. Suggested by our results, the eels from the spawning site may separate into two groups when they are near to the south of Taiwan, and then move to the different estuaries in China. It could be proposed that, in general, the migration direction is from south to north along the east coast in China.

  15. Investigating bomb radiocarbon transport in the southern Pacific Ocean with otolith radiocarbon

    Science.gov (United States)

    Grammer, G. L.; Fallon, S. J.; Izzo, C.; Wood, R.; Gillanders, B. M.

    2015-08-01

    To explore the transport of carbon into water masses from the surface ocean to depths of ∼ 1000 m in the southwest Pacific Ocean, we generated time series of radiocarbon (Δ14C) from fish otoliths. Otoliths (carbonate earstones) from long-lived fish provide an indirect method to examine the "bomb pulse" of radiocarbon that originated in the 1950s and 1960s, allowing identification of changes to distributions of 14C that has entered and mixed within the ocean. We micro-sampled ocean perch (Helicolenus barathri) otoliths, collected at ∼ 400- 500 m in the Tasman Sea, to obtain measurements of Δ14C for those depths. We compared our ocean perch Δ14C series to published otolith-based marine surface water Δ14C values (Australasian snapper (Chrysophrys auratus) and nannygai (Centroberyx affinis)) and to published deep-water values (800-1000 m; orange roughy (Hoplostethus atlanticus)) from the southwest Pacific to establish a mid-water Δ14C series. The otolith bomb 14C results from these different depths were consistent with previous water mass results in the upper 1500 m of the southwest Pacific Ocean (e.g. World Ocean Circulation Experiment and Geochemical Ocean Sections Study). A comparison between the initial Δ14C bomb pulse rise at 400-500 m suggested a ventilation lag of 5 to 10 yr, whereas a comparison of the surface and depths of 800-1000 m detailed a 10 to 20 yr lag in the time history of radiocarbon invasion at this depth. Pre-bomb reservoir ages derived from otolith 14C located in Tasman Sea thermocline waters were ∼ 530 yr, while reservoir ages estimated for Tasman Antarctic intermediate water were ∼ 730 yr.

  16. Spatial variation in elemental composition of otoliths of three species of fish (family Sparidae)

    Science.gov (United States)

    Gillanders, B. M.; Kingsford, M. J.

    2003-08-01

    Determining the nursery habitat of fishes that have moved from estuarine nursery habitats is difficult. The elemental fingerprints of otoliths of three species of sparids were determined to investigate their utility as a natural tag of the nursery habitat. Juvenile Pagrus auratus (snapper), Rhabdosargus sarba (tarwhine) and Acanthopagrus australis (bream) were collected from two sites in each of 15, six and three estuaries, respectively, and their otoliths analysed by solution-based inductively coupled plasma-mass spectrometry. Significant differences in otolith chemistry were found for all three species of juveniles collected from different estuaries. The same patterns among estuaries were not seen for all species, although it was not possible to sample the same sites within an estuary for all species. For bream, significant differences in otolith chemistry were found among all three estuaries, whereas for tarwhine the six estuaries were separated into three groups. For snapper, a number of estuaries could be separated, but there was some overlap for other estuaries. All three species were collected from the same site within one estuary and their otoliths analysed. Significant differences were found among species, but the implication of this finding remains unclear as the three species show differences in microhabitat use and may also differ in age. Because the elemental fingerprints of juveniles vary among estuaries or groups of estuaries, the nursery or recruitment estuary of adult fish could now be determined by analysing the juvenile region of adult otoliths. Thus, connectivity between estuaries and open coastal populations could be determined. Such information will have major implications for fisheries management because it will provide information on the distance that fish have moved from their recruitment estuary and the number of estuaries that contribute to each adult population.

  17. The contribution of otoliths and semicircular canals to the perception of two-dimensional passive whole-body motion in humans.

    Science.gov (United States)

    Ivanenko, Y P; Grasso, R; Israël, I; Berthoz, A

    1997-07-01

    1. Perception of two-dimensional (2-D) whole-body passive motion in the horizontal plane was studied in twelve blindfolded healthy volunteers: pure rotation in place (180 deg), linear motion (4.5 m) and a semicircular trajectory (radius, 1.5 m; angular acceleration, 0.2 rad s-2) were applied in random sequence by means of a remote-controlled robot equipped with a racing-car seat. The seat orientation in the horizontal plane was controlled by the experimenter, independent of the robot trajectory. Thus different degrees of otolith-canal interaction were obtained. The maximal linear acceleration during the semicircular trajectory was 0.1 g; however, the linear acceleration vector was complex as it rotated relative to the subject's head. 2. In the first of two sessions, subjects were instructed to maintain an angular pointer oriented towards a remote (15 m) previously seen target during the passive movements. In the second session they had to make a drawing of the path of the perceived trajectory, after the movement was finished. 3. The results showed that, on average, the movement of the pointer matched the dynamics of the rotatory component of the 2-D motion well. This suggests that, in the range of linear accelerations used in this study, no appreciable influence of otolith input on canal-mediated perception of angular motion occurred. 4. The curvature of the drawn paths was mostly explained by the input to the semicircular canals. Subjects' reconstruction of motion did not account for the directional dynamics of the input to the otoliths occurring during passive motion. 5. This finding proves that reconstructing trajectory in space does not imply a mathematically perfect transformation of the linear and angular motion-related inputs into a Cartesian or polar 2-D representation. Physiological constraints on the interaction between motion direction and change of heading play an important role in motion perception. PMID:9234209

  18. Validation of otolith increment formation and the growth rate of fat greenling larvae

    OpenAIRE

    JOH, Mikimasa; Joh, Takashi; Matsu-ura, Teppei; Takatsu, Tetsuya

    2008-01-01

    We validated the daily formation 0f otolith increments of reared fat greenling Hexagrammos otakii larvae and examined the growth patterns of wild lavae. The mean notochord Length and otolith radius of newly hatched larvae were 8.31 mm and 273μm, respectively. Newly hatched larvae had some increments on their lapilli and a check was formed at hatching (hatch check). The relattonship between age and the number of increments formed outside the hatch chcck (NI)was linear regression (Nl=0.99Age-0....

  19. Changing otolith/fish size ratios during settlement in two tropical damselfishes

    Science.gov (United States)

    Baumann, H.; Gagliano, M.

    2011-09-01

    Otolith-fish size (O-L) relationships were analysed in recruits of two damselfish species ( Chrysiptera rollandi and Pomacentrus amboinensis) before and after cohorts had settled onto reefs surrounding Lizard Island in Australia's Great Barrier Reef. Unexpectedly, O was found to be unrelated to L in pre-settlers of both species. Settlers sampled only 12-15 days later, however, exhibited the expected isometric O-L relationship. This intriguingly rapid change—due to either variable growth, selective mortality or a combination of both—renders otolith increment widths inconsistent proxies for daily somatic growth rates in the pre- versus post-settlement stages of these pomacentrids.

  20. On the Role of the CNS in regulating the Mineralization of inner Ear Otoliths of Fish

    Science.gov (United States)

    Anken, R.

    This presentation will address recent phenomenological findings, according to which the brain obviously plays a prominent role in regulating the mineralization of fish otoliths in dependence of the gravity vector. In brief, the hypothetical model for the respective regulatory processes is as follows: Calcification of otoliths might be guided by an (efferent) neuronal modulation of (1) the release of calcium at tight junctions in the macular epithelia (2) macular carbonic anhydrase activity (which in turn is responsible for CaCO_3 deposition) (3) the chemical composition of matrix proteins This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

  1. Variation of Ca, Sr, Ba and Mg in the Otolith of Mudskipper in West Coast of Peninsular Malaysia

    OpenAIRE

    A.S. Sarimin; M.A. Ghaffar; C.A.R. Mohamed

    2009-01-01

    A study on elemental composition in the otolith of giant mudskipper, Periophthalmodon schlosseri, was done from June to October 2003. Specimens were obtained from the mangrove areas of Kuala Selangor, Sepang and Melaka in the west coast of Peninsular Malaysia. A total of 70 sagitta otoliths were analyzed to detect variation of Sr, Ba and Mg, replacing the natural chemical composition of the otolith, which is the calcium carbonate (CaCO3). The average ratio of Sr:Ca was 0.11x10-4, Ba:Ca...

  2. Factors determining variations in otolith microincrement width of demersal juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.; Böttcher, U.

    2003-01-01

    -circulation model. The best fit to observed otolith growth rates was obtained under the assumption that fish on the slope performed daily vertical migrations between the warm surface layer and the cold bottom layer. The data suggested that fish stayed in the surface layer during the first increment-pattern interval...

  3. Metals content in otoliths of Dicentrarchus labrax from two fish farms of Sicily.

    Science.gov (United States)

    Traina, A; Oliveri, E; Salvagio Manta, D; Barra, M; Mazzola, S; Cuttitta, A

    2015-06-01

    Otoliths of cultured sea bass (Dicentrarchus labrax) from two different fish farms of Sicily were collected and analyzed by using inductively coupled plasma optical emission spectroscopy. Metal content (Ba, Cd, Fe, Mg, Mn, Sr, and Zn) was measured in order to test the potential use of biogenic carbonates as proxies of dissimilar environmental conditions since the fish farms are implanted in opposite coastal marine areas (Gulf of Castellammare and Gulf of Gela) characterized by different oceanographic features and human activities. Cluster analysis discriminates samples as different groups on the basis of metal content. Results show that concentrations of Sr in the otoliths have a similar range of distribution and not significantly different between the two farms. Otherwise, Fe, Mg, Mn, and Cd show higher concentrations in otoliths collected from fish reared in the farm in the southern coast (Gulf of Gela), an area subject to a great anthropogenic pressure. Zn is the only element with higher values in the otoliths from the farm in the northern coast (Gulf of Trappeto) probably due to industrial effluent. In this work, obtained data confirm the high potential of trace elements measurements in these biogenic carbonates as proxies of different environmental conditions. PMID:25980727

  4. Marking pike fry otoliths with alizarin complexone and strontium : an evaluation of methods

    DEFF Research Database (Denmark)

    Skov, Christian; Grønkjær, P.; Nielsen, C.

    2001-01-01

    Laboratory experiments demonstrated that both alizarin complexone and strontium are useful in mass marking of pike Esox lucius fry otoliths. Visual detection of alizarin complexone marks was considered more reliable than the quantitative analysis of strontium for differentiating marked and unmarked...

  5. Lapillus otoliths of the Cathorops spixii (Spix & Agassiz, 1829 and Genidens genidens (Cuvier, 1829 (Actinopterygii - Ariidae

    Directory of Open Access Journals (Sweden)

    Barbara Maichak de Carvalho

    2014-08-01

    Full Text Available The aim of this study was to analyze the morphology and morphometry of lapillus otoliths of the catfishes Cathorops spixii and Genidens genidens from the coast of Paraná State, Brazil. We used 147 lapillus from C. spixii and 96 from G. genidens, of different size classes. Otoliths were characterized with smooth margins for both species but with different shapes: oblong for C. spixii and oval for G. genidens. The morphological differentiation between the two species is in the anterior region: rounded for C. spixii and pointed for G. genidens. The t-test results for otolith measurements were: length (t value = -2.88; p = 0.0042, height (t value = -6.87; p < 0.000001, anterior angle (t value= 9.84; p = 0.000001 and posterior angle (t value =0.41; p = 0.68. The results show that lapillus otoliths of C. spixii and G. genidens differ in the shape of the anterior region and in the anterior angle, which facilitate the differentiation between the two species in trophic ecology studies on ichthyophagous.

  6. Identifying blue whiting (Micromesistius poutassou) stock structure in the Northeast Atlantic by otolith shape analysis

    DEFF Research Database (Denmark)

    Mahe, Kélig; Oudard, Clémence; Mille, Tiphaine;

    2016-01-01

    Information on stock identification and spatial stock structure provide a basis for understanding fish population dynamics and improving fisheries management. In this study, otolith shape analysis was used to study the stock structure of blue whiting (Micromesistius poutassou) in the northeast At...

  7. Otoliths in continental shelf and slope surficial sediments off Saurashtra, Arabian Sea, India and their significance

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; John, S.; Rana, R.S.

    is in progress and will be reported in due course. This preliminary report which is the first report from the northern Arabian Sea on fossil fish otolith may help as an additional tool in the reconstruction of paleoenvironment and in assessing the latitudinal...

  8. Integration of semicircular canal and otolith information for multisensory orientation stimuli

    Science.gov (United States)

    Ormsby, C. C.; Young, L. R.

    1977-01-01

    This paper presents a model for the perception of dynamic orientation resulting from stimuli which involve both the otoliths and the semicircular canals. The model was applied to several multisensory stimuli and its predictions evaluated. In all cases, the model predictions were in substantial agreement with the known illusions or with the relevant experimental data.

  9. Experimental Evaluation of Stable Isotope Fractionation in Fish Muscle and Otoliths

    Science.gov (United States)

    We investigated an unresolved question in the use of stable isotopes to determine diet and trophic position of fish using both muscle and otoliths. We determined: i) the degree of fractionation of δ13C and δ15N between diet and muscle, and assessed if fractionation was consistent...

  10. Use of an otolith-deficient mutant in studies of fish behavior under microgravity

    Science.gov (United States)

    Ijiri, K.; Mizuno, R.; Eguchi, H.

    In Medaka (Oryzias latipes ), fish of a mutant strain (ha strain) had a malfunction in otolith-vestibular system. The phenotype is expressed when the fish have this recessive gene h a) in a homozygous fashion, and the gene is autosomal. Their( difference from the normal fish was first recognizable in their embryonic stages, with abnormally larger ear vesicles and absence of otoliths called Lapillus inside the vesicles. The time-course study was carried out for the subsequent development of their otoliths. X ray phot ographs of the fish revealed that some adult fish of ha- strain still lack a pair of Lapillus, which mainly serve in sensing the direction of gravity, while others have formed the otoliths partially or completely. Changing the light direction within each day, the ha mutant fish were reared from hatching to young fish. The fish treated showed less dependence on gravity even at the age of 50 days or more. Parabolic flight experiments were carried out to observe the fish behavior under microgravity for ha strain.

  11. Life history of the Small Sandeel, Ammodytes tobianus, inferred from otolith microchemistry. A methodological approach

    Science.gov (United States)

    Laugier, F.; Feunteun, E.; Pecheyran, C.; Carpentier, A.

    2015-11-01

    Knowledge of life history and connectivity between essential ecological habitats are relevant for conservation and management of species and some natural tracers could be used to study the lifecycles of small or short-lived marine fishes. Although sandeels are central in marine food webs and are key species, there is incomplete knowledge about population mixing and migration patterns. For the first time the use of the otolith microchemistry on sandeel species is evaluated in the case of the Small Sandeel. Variations in microchemical fingerprints of 13 trace elements are performed with a Femtosecond LA-ICPM from the core to the margin of sagittal otolith and are compared within and between otoliths extracted from 34 fishes sampled in three different sites along the coast of the south-western English Channel in France. Firstly, preliminary investigations on the validity of the method revealed that Mg/Ca was the only ratio significantly dependant on fish ontogeny and sampling season. Secondly, the Mn/Ca, Zn/Ca, and Cu/Ca ratios enabled us to significantly discriminate among sampling sites. Thirdly, microchemical fingerprints of each life stage varied significantly among sampling sites but not within them, suggesting high site fidelity over relatively short distances. Finally, the fingerprints of all life stages were significantly different from those of the larval and metamorphosis stages. The otolith microchemistry could detect change of signature relative to the shift from a pelagic behaviour to a resident bentho-pelagic behaviour during the middle of the juvenile stage in Small Sandeels. Hence, analysis of trace element fingerprints in otoliths appears to be a valuable method to further studies on ontogenic habitat change, population mixing and variation of life history and be helpful for the management at local or regional scales of short-lived species such as those belonging to other Ammodytidae.

  12. Ocean acidification alters the otoliths of a pantropical fish species with implications for sensory function.

    Science.gov (United States)

    Bignami, Sean; Enochs, Ian C; Manzello, Derek P; Sponaugle, Su; Cowen, Robert K

    2013-04-30

    Ocean acidification affects a wide diversity of marine organisms and is of particular concern for vulnerable larval stages critical to population replenishment and connectivity. Whereas it is well known that ocean acidification will negatively affect a range of calcareous taxa, the study of fishes is more limited in both depth of understanding and diversity of study species. We used new 3D microcomputed tomography to conduct in situ analysis of the impact of ocean acidification on otolith (ear stone) size and density of larval cobia (Rachycentron canadum), a large, economically important, pantropical fish species that shares many life history traits with a diversity of high-value, tropical pelagic fishes. We show that 2,100 μatm partial pressure of carbon dioxide (pCO2) significantly increased not only otolith size (up to 49% greater volume and 58% greater relative mass) but also otolith density (6% higher). Estimated relative mass in 800 μatm pCO2 treatments was 14% greater, and there was a similar but nonsignificant trend for otolith size. Using a modeling approach, we demonstrate that these changes could affect auditory sensitivity including a ∼50% increase in hearing range at 2,100 μatm pCO2, which may alter the perception of auditory information by larval cobia in a high-CO2 ocean. Our results indicate that ocean acidification has a graded effect on cobia otoliths, with the potential to substantially influence the dispersal, survival, and recruitment of a pelagic fish species. These results have important implications for population maintenance/replenishment, connectivity, and conservation efforts for other valuable fish stocks that are already being deleteriously impacted by overfishing. PMID:23589887

  13. Early Eocene SST recorded in clumped isotopic ratios of fish otoliths of North Sea Basin, Belgium

    Science.gov (United States)

    Kannan, P.; Vanhove, D.; Ghosh, P.

    2012-12-01

    Application of clumped isotope thermometry (Ghosh et al., 2007) in well preserved fish otoliths reveals environmental temperature. Fossil specimen of otoliths from marginal marine sedimentary sequence belonging to Ypresian (ca. 50.9 Ma) age reveals environmental temperature and salinity at the time of deposition. Fossil otoliths from two demersal, non-migratory species belonging to genuses namely Neobythitinorum subregularis and Paraconger papoiniti are considered here for this study. Intertaxon clumped isotope ratios allows to distinguish between the temperature habitat of fishes considered. Sedimentary record from the study area suggests large sea level changes and deposition close to shore line (Steurbaut, 2006). It was estimated that 150 kys was the time taken for deposition of the sequence from which the otolith fossils were retrieved (Steurbaut, 2006). The clumped isotope ratio and temperature estimates based on the otoliths composition are classified into two categories. Firstly, genus Neobythitinorum subregularis registering both low temperature (2 and 5°C) and high temperature (30 and 36°C) observed in eight specimens analysed. Secondly, genus Paraconger papoiniti registers warm water condition with consistent temperature of 32±2° C observed in six specimens analysed in this study. Based on the temperature estimates we conclude that North Sea water temperature was 20°C warmer compared to present day record of long time average during early Eocene. This estimate is consistent with previous estimates (Vanhove et al., 2011) based on stable isotope composition. Several hypotheses proposed previously will be explained and the inter-taxonomic variability will be explored in this presentation.

  14. Using otolith chemical and structural analysis to investigate reservoir habitat use by juvenile Chinook salmon Oncorhynchus tshawytscha.

    Science.gov (United States)

    Bourret, S L; Kennedy, B P; Caudill, C C; Chittaro, P M

    2014-11-01

    Isotopic composition of (87) Sr:(86) Sr and natural elemental tracers (Sr, Ba, Mg, Mn and Ca) were quantified from otoliths in juvenile and adult Chinook salmon Oncorhynchus tshawytscha to assess the ability of otolith microchemistry and microstructure to reconstruct juvenile O. tshawytscha rearing habitat and growth. Daily increments were measured to assess relative growth between natal rearing habitats. Otolith microchemistry was able to resolve juvenile habitat use between reservoir and natal tributary rearing habitats (within headwater basins), but not among catchments. Results suggest that 90% (n = 18) of sampled non-hatchery adults returning to the Middle Fork Willamette River were reared in a reservoir and 10% (n = 2) in natal tributary habitat upstream from the reservoir. Juveniles collected in reservoirs had higher growth rates than juveniles reared in natal streams. The results demonstrate the utility of otolith microchemistry and microstructure to distinguish among rearing habitats, including habitats in highly altered systems. PMID:25229130

  15. Torsional vestibulo-ocular reflex measurements for identifying otolith asymmetries possibly related to space motion sickness susceptibility

    Science.gov (United States)

    Peterka, Robert J.

    1993-01-01

    Recent studies have identified significant correlations between space motion sickness susceptibility and measures of disconjugate torsional eye movements recorded during parabolic flights. These results support an earlier proposal which hypothesized that an asymmetry of otolith function between the two ears is the cause of space motion sickness. It may be possible to devise experiments that can be performed in the 1 g environment on earth that could identify and quantify the presence of asymmetric otolith function. This paper summarizes the known physiological and anatomical properties of the otolith organs and the properties of the torsional vestibulo-ocular reflex which are relevant to the design of a stimulus to identify otolith asymmetries. A specific stimulus which takes advantage of these properties is proposed.

  16. Onset of maturity and cohort composition at spawning of Baltic sprat Sprattus sprattus on the basis of otolith macrostructure analysis

    DEFF Research Database (Denmark)

    Reglero, P.; Mosegaard, Henrik

    2006-01-01

    Data on catch per unit effort (CPUE) from the Danish commercial fishery showed dense aggregations of sprat Sprattus sprattus born in 1997 in the main spawning area of the Baltic Sea during May 1999. After the analysis of their otolith macrostructure, these fish were found to have a shorter distance...... to the beginning of the first winter zone compared to fish from the same cohort caught in other months. At the same time, the number of fish with large otoliths at the period of winter zone formation tended to decrease or even disappear. The otolith size at winter zone formation (O-W) was found to be...... a good predictor of sprat total length (L-T) and mass (M) in age group 0 years. Changes in the otolith size distribution over time were related to variations in cohort composition depending on the L-T and M attained during the juvenile stage. Examination of the gonads suggested two life history...

  17. Trace metal incorporation in otoliths of a territorial coral reef fish (Abudefduf saxatilis as an environmental monitoring tool

    Directory of Open Access Journals (Sweden)

    Herrera-Reveles A. T.

    2013-04-01

    Full Text Available Trace metal levels in the otolith external layer of newly Abudefduf saxatilis (Pomacentridae recruits, a common fish of the Caribbean coral reef, were examined as an indicator of recently occupied habitat from the most important coral reefs of the east of Venezuela (Mochima National Park and La Tortuga Island. These otoliths were analyzed trough an Energy-dispersive X-ray spectroscopy (EDS fixed to scanning electron microscopy (SEM. The five trace metals analyzed (Cd, Cu, Hg, Pb and Zn were found at external layer of most evaluated otoliths at all localities, in which %weight of Pb/Ca and Hg/Ca showed the highest values. These results show the bioavailability of evaluated metals at Mochima National Park and La Tortuga Island, and their significant spatial variations on otoliths make evidence of different concentration of Cd, Hg and Pb in water and/or sediments of these locations.

  18. M.I.T./Canadian vestibular experiments on the Spacelab-1 mission: 3. Effects of prolonged weightlessness on a human otolith-spinal reflex

    Science.gov (United States)

    Watt, D. G.; Money, K. E.; Tomi, L. M.

    1986-01-01

    Reflex responses that depend on human otolith organ sensitivity were measured before, during and after a 10 day space flight. Otolith-spinal reflexes were elicited by means of sudden, unexpected falls. In weightlessness, "falls" were achieved using elastic cords running from a torso harness to the floor. Electromyographic (EMG) activity was recorded from gastrocnemius-soleus. The EMG response occurring in the first 100-120 ms of a fall, considered to be predominantly otolith-spinal in origin, decreased in amplitude immediately upon entering weightlessness, and continued to decline throughout the flight, especially during the first two mission days. The response returned to normal before the first post-flight testing session. The results suggest that information coming from the otolith organs is gradually ignored by the nervous system during prolonged space flight, although the possibility that otolith-spinal reflexes are decreased independent of other otolith output pathways cannot be ruled out.

  19. M.I.T./Canadian vestibular experiments on the Spacelab-1 mission. III - Effects of prolonged weightlessness on a human otolith-spinal reflex

    Science.gov (United States)

    Watt, D. G. D.; Money, K. E.; Tomi, L. M.

    1986-01-01

    Reflex responses that depend on human otolith organ sensitivity were measured before, during and after a 10 day space flight. Otolith-spinal reflexes were elicited by means of sudden, unexpected falls. In weightlessness, 'falls' were achieved using elastic cords running from a torso harness to the floor. Electromyographic (EMG) activity was recorded from gastrocnemius-soleus. The EMG response occurring in the first 100-120 ms of a fall, considered to be predominantly otolith-spinal in origin, decreased in amplitude immediately upon entering weightlessness, and continued to decline throughout the flight, especially during the first two mission days. The response returned to normal before the first post-flight testing session. The results suggest that information coming from the otolith organs is gradually ignored by the nervous system during prolonged space flight, although the possibility that otolith-spinal reflexes are decreased independent of other otolith output pathways cannot by ruled out.

  20. The benefits of using otolith weight in statistical fish age classification: a case study of Atlantic cod species

    OpenAIRE

    Bermejo Sánchez, Sergi

    2014-01-01

    In this paper, the discriminative capability of a combination of biological and shape features for fish age classification are analyzed. In particular, the usefulness of otolith weight in several species, in combination with other features such as otolith shape features and biological features such fish length, weight and sex is evaluated. The classification performance for different state-of-the-art statistical learning classifiers (i.e. several non-linear, non-parametric classifiers such di...

  1. Testing the vestibular-ocular reflexes: abnormalities of the otolith contribution in patients with neuro-otological disease.

    OpenAIRE

    Barratt, H; Bronstein, A. M.; Gresty, M A

    1987-01-01

    Conventional vestibular rotation testing with the head centered on the axis stimulates the semicircular canals evoking compensatory eye movements. If the head is placed forwards of the axis in an eccentric position the otoliths are also stimulated by a tangential linear acceleration acting laterally to the skull. In normal subjects the additional otolithic stimulus evokes compensatory eye movements with a higher gain than with head centred, particularly for high frequency (greater than 0.1 Hz...

  2. Carbonic anhydrase is not the only factor regulating otolith mineralization in fish in dependence of the gravitational environment

    Science.gov (United States)

    Beier, M.; Anken, R.

    2006-01-01

    Earlier experiments have shown, that fish otolith growth and mineralization is slowed down by hypergravity (hg). The enzyme carbonic anhydrase (CAH) provides carbonate and, thus, plays a major role in otolith calcification. Indeed, CAH reactivity in inner ear maculae is downregulated by hg. The following experiment was designed in order to elucidate as of whether CAH is the only factor regulating otolith mineralization in dependence of the gravity vector: A first group of larval cichlid fish ( Oreochromis mossambicus) was reared in normal aquarium water at 1 g (1 g-Aq). A second group received hg (3 g, 7 days) as a physical factor to decrease CAH reactivity (3 g-Aq). A third group (1 g-AZ) was (at 1 g) treated with azetazolamide (AZ; 1 g/l), an inhibitor of CAH (the AZ-concentration used resulted in a complete inhibition of CAH as had been proven by a biochemical assessment of enzyme activity). The last group was maintained both in AZ and at hg (3 g-AZ). Both the saccular and utricular otoliths (sagittae and lapilli, respectively) of the 1 g-AZ group showed a decrease in otolith growth (surface area) as compared to the 1 g-Aq animals (1 g-AZ < 1 g-Aq). Similar results were obtained when comparing 3 g-Aq with 1 g-Aq samples (3 g-Aq < 1 g-Aq). Regarding sagittae, AZ treatment had no significant additional effect on otolith mineralization under hg (3 g-AZ = 1 g-AZ). In case of lapilli, however, growth received a further reduction when reared in 3 g-AZ (i.e., 3 g-AZ < 1 g-AZ). Thus, in lapilli, hg and AZ added their effects on otolith growth. This finding clearly indicates that hg does not only act on otolith growth via a regulation of CAH activity.

  3. Neurovestibular adaptation in the utricular otolith in fish to hypergravity exposure and re-adaptation to 1G

    Science.gov (United States)

    Boyle, R.; Popova, Ye.; Varelas, J.; Mofrad, A.

    The inner ear utricular organ senses the sum of inertial force due to head translation and head tilt relative to the gravitational vertical. A change in gravitational force has a profound effect on how an organism maintains equilibrium, and the neural response might involve the peripheral otolith receptors, the brain or both. If the influence of G leads to adaptation and subsequent re-adaptation processes in otolith function upon return to 1G, then this raises fundamental questions: does the transfer from 1G to 3G impart the opposite effects on changes of synaptic structure and gravitational sensitivity seen following G exposure? Do the effects accompanying transfer from the 3G to the 1G conditions resemble in part (as an analog) the transfer from 1G to the G? The use of well-controlled hyper-G experiments allows us to address these questions. Adult fish were placed in groups and exposed to 3G for 1, 2, 3, 4, 5, 8, 16, 24, and 32 days. Re-adaptation to 1G was studied in 3G exposure (4-and 16-day) following 1-8 day of recovery. Typically ∼60 afferents are well characterized in each fish. Directional sensitivity of each afferent defined as the vector with the magnitude measured in unit gain (imp/s/g) is determined. It allows us to consider the diagram of directional sensitivity of the whole macula. For quantitative estimates of the change of afferent sensitivity in hyper-G experiments two functions have been introduced: probability function (maximum sensitivity of each afferent is plotted as a percentage of population sensitivity whose values is less than the individual sensitivity) and the frequency function (or probability density function-PDF) of the population of afferents on the gain. These functions enable us to extract additional information about the details of evolution of gain-afferent distribution. Results to date show a biphasic pattern in reaction to 3G exposures: an initial sensitivity up-regulation (3-and 4-day) followed by a significant decrease

  4. UREA/ammonium ion removal system for the orbiting frog otolith experiment. [ion exchange resins for water treatment during space missions

    Science.gov (United States)

    Schulz, J. R.; Anselmi, R. T.

    1976-01-01

    The feasibility of using free urease enzyme and ANGC-101 ion exchange resin to remove urea and ammonium ion for space system waste water applications was studied. Specifically examined is the prevention of urea and ammonia toxicity in a 30-day Orbiting Frog Otolith (OFO) flight experiment. It is shown that free urease enzyme used in conjunction with ANGC-101 ion-exchange resin and pH control can control urea and amonium ion concentration in unbuffered recirculating water. In addition, the resin does not adversely effect the bullfrogs by lowering the concentration of cations below critical minimum levels. Further investigations on bioburden control, frog waste excretion on an OFO diet, a trade-off analysis of methods of automating the urea/ammonium ion removal system and fabrication and test of a semiautomated breadboard were recommended as continuing efforts. Photographs of test equipment and test animals are shown.

  5. Natural growth, otolith shape and diet analyses of Odontesthes nigricans Richardson (Atherinopsidae) from southern Patagonia

    Science.gov (United States)

    Lattuca, M. E.; Lozano, I. E.; Brown, D. R.; Renzi, M.; Luizon, C. A.

    2015-12-01

    Age and growth, otolith shape and diet of Odontesthes nigricans were analysed in order to provide an insight into the life history of the species and furthermore, to assess their possible use as a tool for discriminating silverside populations from the South Atlantic Ocean (Punta María) and Beagle Channel waters (Varela Bay). The age and growth analysis was performed by counting daily increments and annual marks in sagittae otoliths. Length-at-age data of individuals diet, which also showed significant site dependence. The use of all these analyses contributed to a holistic approach which maximized the likelihood of correctly identifying both O. nigricans populations in the southernmost limit of the species distribution.

  6. Spatial population structure of the Neotropical tiger catfish Pseudoplatystoma metaense: skull and otolith shape variation.

    Science.gov (United States)

    Pérez, A; Fabré, N N

    2013-05-01

    Using geometric morphometrics, the skull and otolith of tiger catfish Pseudoplatystoma metaense were analysed to identify population structure in tributaries of the Apure River (i.e. the Sarare, Caparo, Guanare, Portuguesa and San Carlos Rivers) in the Orinoco basin, Venezuela. The analyses show uniformity in skull and otolith shapes of P. metaense within and among four tributaries, with only the Caparo River showing significant differences. Within the Apure basin, the stock of P. metaense was differentiated through spawning, refuge and nursery areas. This study concludes that populations of P. metaense from each major tributary in the Orinoco basin should be considered as part of a metapopulation system for management purposes. Human disturbances in the catchment have directly reduced the spawning areas available to this species, decreased the total biomass and changed the spatial distribution of spawning areas. PMID:23639147

  7. Motion sickness and otolith sensitivity - A pilot study of habituation to linear acceleration

    Science.gov (United States)

    Potvin, A. R.; Sadoff, M.; Billingham, J.

    1977-01-01

    Astronauts, particularly in Skylab flights, experienced varying degrees of motion sickness lasting 3-5 days. One possible mechanism for this motion sickness adaptation is believed to be a reduction in otolith sensitivity with an attendant reduction in sensory conflict. In an attempt to determine if this hypothesis is valid, a ground-based pilot study was conducted on a vertical linear accelerator. The extent of habituation to accelerations which initially produced motion sickness was evaluated, along with the possible value of habituation training to minimize the space motion sickness problem. Results showed that habituation occurred for 6 of the 8 subjects tested. However, in tests designed to measure dynamic and static otolith function, no significant differences between pre- and post-habituation tests were observed. Cross habituation effects to a standard Coriolis acceleration test were not significant. It is unlikely that ground-based pre-habituation to linear accelerations of the type examined would alter susceptibility to space motion sickness.

  8. Micro-PIXE line-scan measurements of the yellow eel's otolith

    International Nuclear Information System (INIS)

    Anguilla japonica has a high economic value. The abundance had decreased significantly due to excessive fishing and change in the aquatic ecology. Life history patterns of A. japonica have been studied to prevent excessive fishing and make management plans. Strontium (Sr)-calcium (Ca) ratio along a line down the long axis from the core to the edge of the yellow eel's otolith was measured using micro proton induced X-ray emission (micro-PIXE). An efficient and precise method was proposed to locate the core where an otolith begins to grow, based on Sr concentration and distribution. Using this method, life history patterns of the yellow eels collected from Jingjiang River in China were investigated. In general, there are two types, river eels and estuarine eels.

  9. Application of a nuclear microprobe to the study of fish otoliths and scales

    International Nuclear Information System (INIS)

    We have measured the distributions of some of the elements in otoliths and scales from several species of teleost (bony) fish, with the aim of learning more about the environment of a fish at different stages in its life, and testing the validity of present methods for determining the age of a fish. The ratio of strontium to calcium in successive layers of an otolith is extremely sensitive to water temperature, so it is possible to trace the temperature history of the fish, probably including seasonal variations. The distributions of calcium and fluorine in scales differ strikingly between species and sufficiently in a single scale to suggest that environmental information may be captured there as well. (orig.)

  10. ShapeR: an R package to study otolith shape variation among fish populations.

    Science.gov (United States)

    Libungan, Lísa Anne; Pálsson, Snæbjörn

    2015-01-01

    ShapeR is an open source software package that runs on the R platform and is specifically designed to study otolith shape variation among fish populations. The package extends previously described software used for otolith shape analysis by allowing the user to automatically extract closed contour outlines from a large number of images, perform smoothing to eliminate pixel noise, choose from conducting either a Fourier or Wavelet transform to the outlines and visualize the mean shape. The output of the package are independent Fourier or Wavelet coefficients which can be directly imported into a wide range of statistical packages in R. The package might prove useful in studies of any two dimensional objects. PMID:25803855

  11. Application of a nuclear microprobe to the study of fish otoliths and scales

    Science.gov (United States)

    Coote, G. E.; Gauldie, R. W.; West, I. F.

    1991-03-01

    We have measured the distributions of some of the elements in otoliths and scales from several species of teleost (bony) fish, with the aim of learning more about the environment of a fish at different stages in its life, and testing the validity of present methods for determining the age of a fish. The ratio of strontium to calcium in successive layers of an otolith is extremely sensitive to water temperature, so it is possible to trace the temperature history of the fish, probably including seasonal variations. The distributions of calcium and fluorine in scales differ strikingly between species and sufficiently in a single scale to suggest that environmental information may be captured there as well.

  12. Application of a nuclear microprobe to the study of fish otoliths and scales

    Energy Technology Data Exchange (ETDEWEB)

    Coote, G.E. (Inst. of Nuclear Sciences, Lower Hutt (New Zealand)); Gauldie, R.W. (Hawaii Inst. of Geophysics, Honolulu (USA)); West, I.F. (Fisheries Research Centre, Wellington (New Zealand))

    1991-03-01

    We have measured the distributions of some of the elements in otoliths and scales from several species of teleost (bony) fish, with the aim of learning more about the environment of a fish at different stages in its life, and testing the validity of present methods for determining the age of a fish. The ratio of strontium to calcium in successive layers of an otolith is extremely sensitive to water temperature, so it is possible to trace the temperature history of the fish, probably including seasonal variations. The distributions of calcium and fluorine in scales differ strikingly between species and sufficiently in a single scale to suggest that environmental information may be captured there as well. (orig.).

  13. Comparative study on nano-mechanics and thermodynamics of fish otoliths.

    Science.gov (United States)

    Dongni, Ren; Yonghua, Gao; Qingling, Feng

    2013-01-01

    Fish otolith is a kind of typical natural biomineral, which is composed of calcium carbonate and organic matrix. In fresh water carp otolith, the inorganic phase of lapillus is pure aragonite, and for asteriscus it is pure vaterite. In this research, the phase composition, phase transformation, mechanical property and solubility of lapillus and asteriscus were studied. And results showed that, the organic content of lapillus was higher than that of asteriscus; the phase-transition temperature of lapillus (aragonite-calcite) and asteriscus (vaterite-calcite) both happened between 520 and 640 °C; the nano-mechanical property of lapillus was better than that of asteriscus; the solubility of asteriscus powder was higher than that of lapillus powder. PMID:25428035

  14. Modelling the mixing of herring stocks between the Baltic and the North Sea from otolith data

    DEFF Research Database (Denmark)

    Ulrich, Clara; Post, Søren Lorentzen; Worsøe Clausen, Lotte;

    2012-01-01

    Herring catches in the western Baltic, Kattegat and Skagerrak consist of a mixture of stocks, mainly North Sea autumn spawners (NSAS) and western Baltic spring spawners (WBSS), which is managed through a single TAC. Catches of these two stocks are split using otolith microstructures from Danish and...... Swedish commercial landings and surveys samples for the purpose of stock assessment. But the split estimates from sampling data are highly variable and noisy. Better understanding of the migration and exploitation patterns involved could therefore potentially improve the stock assessment as well as...... provide solutions to the complex management of this mix. The stock‐specific seasonal trends in distribution of the two main stocks from otolith data were analysed using a generalized linear mixed model (GLMM) of stock composition. The results show a clear seasonal and age‐related pattern and are...

  15. Three-dimensional organization of otolith-ocular reflexes in rhesus monkeys. II. Inertial detection of angular velocity

    Science.gov (United States)

    Angelaki, D. E.; Hess, B. J.

    1996-01-01

    1. The dynamic contribution of otolith signals to three-dimensional angular vestibuloocular reflex (VOR) was studied during off-vertical axis rotations in rhesus monkeys. In an attempt to separate response components to head velocity from those to head position relative to gravity during low-frequency sinusoidal oscillations, large oscillation amplitudes were chosen such that peak-to-peak head displacements exceeded 360 degrees. Because the waveforms of head position and velocity differed in shape and frequency content, the particular head position and angular velocity sensitivity of otolith-ocular responses could be independently assessed. 2. During both constant velocity rotation and low-frequency sinusoidal oscillations, the otolith system generated two different types of oculomotor responses: 1) modulation of three-dimensional eye position and/or eye velocity as a function of head position relative to gravity, as presented in the preceding paper, and 2) slow-phase eye velocity as a function of head angular velocity. These two types of otolith-ocular responses have been analyzed separately. In this paper we focus on the angular velocity responses of the otolith system. 3. During constant velocity off-vertical axis rotations, a steady-state nystagmus was elicited that was maintained throughout rotation. During low-frequency sinusoidal off-vertical axis oscillations, dynamic otolith stimulation resulted primarily in a reduction of phase leads that characterize low-frequency VOR during earth-vertical axis rotations. Both of these effects are the result of an internally generated head angular velocity signal of otolithic origin that is coupled through a low-pass filter to the VOR. No change in either VOR gain or phase was observed at stimulus frequencies larger than 0.1 Hz. 4. The dynamic otolith contribution to low-frequency angular VOR exhibited three-dimensional response characteristics with some quantitative differences in the different response components. For

  16. Using elemental chemistry of fish otoliths to determine connectivity between estuarine and coastal habitats

    Science.gov (United States)

    Gillanders, B. M.

    2005-07-01

    Connectivity between estuarine and coastal populations is poorly understood but fundamental to the study of population dynamics, as well as the design of effective conservation and management strategies. Naturally occurring elemental signatures (or composition) in the otoliths of fish are an ideal natural tag due to the metabolic inertness of otoliths, continuous growth including daily increments and incorporation of elements that are influenced by environmental variables. In this paper, I review the use of otolith chemistry to determine connectivity between estuarine and coastal habitats focusing on assumptions of using elemental signatures as natural tags, consequences of violating these assumptions and finally providing examples of the application of natural tags to determine connectivity. As a first step to determining connectivity, it is important to determine whether fish residing in different estuaries do in fact have different elemental signatures. Spatial differences must be determined for each species of interest since variability has been found between species collected from the same location. For retrospective determination of origins of fish, it is also necessary to ensure either that there is no temporal variation at both the small (e.g. among months within a year) and large scale (e.g. among years) or to match adults to the appropriate year class of juveniles. In addition, fish should be collected from all possible source groups contributing to the group mixture. The majority of studies that show connectivity between estuarine and open coastal populations using otolith chemistry have determined the contribution of different habitats or estuaries to the adult population, although natal homing has also been examined.

  17. Stable isotope marking of otoliths during vaccination: a novel method for mass-marking fish

    OpenAIRE

    Warren-Myers, Fletcher; Dempster, Tim; Fjelldal, Per Gunnar; Hansen, Tom; Jensen, Arne J.; Swearer, Stephen E.

    2014-01-01

    Tagging or marking of fishes enables the collection of population-based information for ecological research, yet few techniques enable 100% mark detection success. We tested a new mass-marking technique: otolith marking with enriched stable isotopes delivered during vaccination. Atlantic salmon (Salmo salar) parr were injected in either the abdominal cavity or muscle with a combination of enriched 137Ba, 86Sr and 26Mg, using 1 of 3 carrier solutions (water, vaccine, vaccine mimic). Laser abla...

  18. Analysis of matrix proteins of otolith in upside-down catfish

    Science.gov (United States)

    Ohnishi, K.; Okamoto, N.; Takahashi, A.; Ohnishi, T.

    We have previously suggested that the calcium density of the otolith in upside-down swimming Synodontis nigriventris is lower than that in upside-up swimming Synodontis multipunctatus Biol Space Sci 2002 In this study we examined EDTA-soluble matrix proteins of otolith in the utricle of the catfish S nigriventris S multipunctatus and upside-up swimming Synodontis brichadi and goldfish Carassius auratus We detected two main bands about 55 kD and 80 kD with SDS-PAGE in the 3 species of the catfish In cntrast goldfish had the about 55 kD band alone The band of about 80 kD was consisted of two sub-bands a lighter and a heavier band A lighter band was observed in S brichadi and a heavier band was observed in S nigriventris S multipunctatus had the both bands Furthermore mass spectrometric analysis showed there were some proteins of molecular weight under 14 kD The molecular weights of the proteins were different among the fishes These results suggest that many different kinds of matrix protein may cause different degree of calcification in otolith formation

  19. Juvenile life history of NE Atlantic orange roughy from otolith stable isotopes

    Science.gov (United States)

    Shephard, Samuel; Trueman, Clive; Rickaby, Rosalind; Rogan, Emer

    2007-08-01

    Otoliths of pre-recruit orange roughy ( Hoplostethus atlanticus) were sampled from different deep-water habitats ('flat' and 'hill') and areas (north and south) on the Porcupine Bank. Age-based profiles for stable isotopes of carbon (δ 13C) and oxygen (δ 18O) in these otoliths were developed, which provide a fish life-history record of water depth and metabolic activity. These profiles were consistent among all individuals implying endogenous (ontogenic) influences on the pattern. The data indicate that post-larval orange roughy are mesopelagic active foragers, early juvenile fish move into a low energy deep-demersal phase, and older pre-recruit orange roughy assume the habitat depth and metabolic rate typical of adults. Comparison of otolith stable isotope profiles among areas and habitats on the Porcupine Bank suggest that juvenile orange roughy from South 'hill' and 'flat' habitats experience differing temperature and metabolic status at certain life stages. This may reflect oceanographic and ecological divergence between the two environments and suggests fine-scale population structure that may reduce resilience to exploitation.

  20. Acoustically Induced Streaming Flows near a Model Cod Otolith and their Potential Implications for Fish Hearing

    Energy Technology Data Exchange (ETDEWEB)

    Kotas, Charlotte W [ORNL; Rogers, Peter [Georgia Institute of Technology; Yoda, Minami [Georgia Institute of Technology

    2011-01-01

    The ears of fishes are remarkable sensors for the small acoustic disturbances associated with underwater sound. For example, each ear of the Atlantic cod (Gadus morhua) has three dense bony bodies (otoliths) surrounded by fluid and tissue, and detects sounds at frequencies from 30 to 500 Hz. Atlantic cod have also been shown to localize sounds. However, how their ears perform these functions is not fully understood. Steady streaming, or time-independent, flows near a 350% scale model Atlantic cod otolith immersed in a viscous fluid were studied to determine if these fluid flows contain acoustically relevant information that could be detected by the ear s sensory hair cells. The otolith was oscillated sinusoidally at various orientations at frequencies of 8 24 Hz, corresponding to an actual frequency range of 280 830 Hz. Phaselocked particle pathline visualizations of the resulting flows give velocity, vorticity, and rate of strain fields over a single plane of this mainly two-dimensional flow. Although the streaming flows contain acoustically relevant information, the displacements due to these flows are likely too small to explain Atlantic cod hearing abilities near threshold. The results, however, may suggest a possible mechanism for detection of ultrasound in some fish species.

  1. Temporal variability in estuarine fish otolith elemental fingerprints: Implications for connectivity assessments

    Science.gov (United States)

    Reis-Santos, Patrick; Gillanders, Bronwyn M.; Tanner, Susanne E.; Vasconcelos, Rita P.; Elsdon, Travis S.; Cabral, Henrique N.

    2012-10-01

    The chemical composition of fish otoliths can provide valuable information for determining the nursery value of estuaries to adult populations of coastal fishes. However, understanding temporal variation in elemental fingerprints at different scales is important as it can potentially confound spatial discrimination among estuaries. Otolith elemental ratios (Li:Ca, Mg:Ca, Mn:Ca, Cu:Ca, Sr:Ca, Ba:Ca and Pb:Ca) of Platichthys flesus and Dicentrarchus labrax, from several estuaries along the Portuguese coast in two years and three seasons (spring, summer and autumn) within a year, were determined via Laser Ablation Inductively Coupled Plasma Mass Spectrometry. Elemental fingerprints varied significantly among years and seasons within a year but we achieved accurate classifications of juvenile fish to estuarine nursery of origin (77-96% overall cross-validated accuracy). Although elemental fingerprints were year-specific, variation among seasons did not hinder spatial discrimination. Estuarine fingerprints of pooled seasonal data were representative of the entire juvenile year class and attained high discrimination (77% and 80% overall cross-validated accuracy for flounder and sea bass, respectively). Incorporating seasonal variation resulted in up to an 11% increase in correct classification of individual estuaries, in comparison to seasons where accuracies were lowest. Overall, understanding the implications of temporal variations in otolith chemistry for spatial discrimination is key to establish baseline data for connectivity studies.

  2. Is geometric morphometrics efficient for comparing otolith shape of different fish species?

    Science.gov (United States)

    Ponton, Dominique

    2006-06-01

    The 2D shape of sagittae of Encrasicholina devisi, E. heteroloba, E. cf. punctifer, and Stolephorus indicus, four tropical Engraulididae of New Caledonia, was studied with 1) dimensionless shape descriptors (form factor, roundness, and aspect ratio); 2) elliptic Fourier analysis (EFA) and Fast Fourier Transform (FFT) of 2D outline; and 3) geometric morphometrics (GM) based on four standard landmarks and nine semi-landmarks. The largest sagittae of E. cf. punctifer were lacier, i.e., had a smaller form factor, than the sagittae of the other species. The sagittae of E. devisi and S. indicus were more roundish, and presented a lower aspect ratio, than those of E. heteroloba and E. cf. punctifer. Between-class correspondence analysis (COA) indicated that between-species inertia was the lowest when based on the 96 Fourier coefficients originating from EFA, and the highest when based on the 22 partial warps originating from GM. As otoliths of different sizes from different species presented similar shapes, relative between-species inertia increased markedly when length, width, perimeter, and area were added to the set of variables originating from EFA, FFT, or GM. Despite otoliths having only a few, sparsely located, homologous landmarks, GM appeared slightly more efficient in distinguishing the sagittae of the four species and allowed visualization of the modification of otolith shape as they grow. PMID:16526058

  3. Vesicular bodies in fish maculae are artifacts not contributing to otolith growth.

    Science.gov (United States)

    Ibsch, M; Anken, R H; Vöhringer, P; Rahmann, H

    2001-03-01

    The presence, morphology and possible origin of vesicle-like bodies (VBs) within the inner ear macular otolithic membrane of developmental stages of cichlid fish Oreochromis mossambicus and neonate (i.e. functionally fully developed except the reproductive organs) swordtail fish Xiphophorus helleri were analyzed by means of transmission and scanning electron microscopy (TEM and SEM, respectively) employing various fixation procedures. Some authors believe that these VBs are involved in the formation of the organic phase of inner ear otoliths (or statoliths in birds and mammals). Decreasing the osmolarity of the fixation medium from a value rather close to that of native fresh water fish tissue (i.e. 250 mOsm and 290--300 mOsm, respectively) to a value of fixatives mostly employed in TEM studies (ca. 190 mOsm), the amount of VBs increased and the components of sensory inner ear tissue increasingly dilated. Whilst a conventional prefixation with aldehydes followed by osmium tetroxide postfixation yielded numerous VBs, only few of them were observed when the tissue was fixed with aldehydes and osmium tetroxide simultaneously. Therefore, the results demonstrate that inner ear sensory epithelia are extremely sensitive to altering fixation media. On this background it must be concluded that VBs are fixative (i.e. glutaraldehyde) induced artificial structures, so-called membrane blisters. Thus, the protein matrix of otoliths (and possibly that of statoliths in higher vertebrates) is rather provided by secretion processes than by the release of vesicles. PMID:11223298

  4. Low interbasin connectivity in a facultatively diadromous fish: evidence from genetics and otolith chemistry.

    Science.gov (United States)

    Hughes, Jane M; Schmidt, Daniel J; Macdonald, Jed I; Huey, Joel A; Crook, David A

    2014-03-01

    Southern smelts (Retropinna spp.) in coastal rivers of Australia are facultatively diadromous, with populations potentially containing individuals with diadromous or wholly freshwater life histories. The presence of diadromous individuals is expected to reduce genetic structuring between river basins due to larval dispersal via the sea. We use otolith chemistry to distinguish between diadromous and nondiadromous life histories and population genetics to examine interbasin connectivity resulting from diadromy. Otolith strontium isotope ((87) Sr:(86) Sr) transects identified three main life history patterns: amphidromy, freshwater residency and estuarine/marine residency. Despite the potential for interbasin connectivity via larval mixing in the marine environment, we found unprecedented levels of genetic structure for an amphidromous species. Strong hierarchical structure along putative taxonomic boundaries was detected, along with highly structured populations within groups using microsatellites (FST  = 0.046-0.181), and mtDNA (ΦST  = 0.498-0.816). The presence of strong genetic subdivision, despite the fact that many individuals reside in saline water during their early life history, appears incongruous. However, analysis of multielemental signatures in the otolith cores of diadromous fish revealed strong discrimination between river basins, suggesting that diadromous fish spend their early lives within chemically distinct estuaries rather than the more homogenous marine environment, thus avoiding dispersal and maintaining genetic structure. PMID:24410817

  5. Origin of yellow kingfish, Seriola lalandi, from Lord Howe Island, Australia, inferred from otolith chemistry

    International Nuclear Information System (INIS)

    Yellowtail kingfish, Seriola lalandi (Family Carangidae), sustain important commercial and recreational fisheries in New South Wales (NSW), Australia. However, little is known about their population structure, particularly whether the kingfish around Lord Howe Island (LHI) comprise a distinct stock, separate from that of the NSW stock. We examined the otolith chemistry from juvenile kingfish collected from LHI, several NSW sites and Elizabeth and Middleton reefs (EMR) and compared those elemental signatures to the juvenile portion of adult otoliths collected from LHI to determine where the adults may have originated. Our results indicate a robust separation in otolith signatures from different locations (error rate of classification ranged from 3.5% to 9.9%), and suggest that a significant proportion of the adult kingfish sampled (28%) may have originated in the waters around LHI or nearby EMR. Further research may indicate that the management of kingfish in NSW waters could benefit from a more spatially explicit strategy. (author). 32 refs., 3 figs., 2 tabs.

  6. Population discrimination by strontium-calcium concentration ratios of sagittal otoliths taken from the Japanese flounder, Paralichthys olivaceus

    International Nuclear Information System (INIS)

    For the purpose of obtaining basic data to understand the population dynamics of the Japanese flounder, Paralichthys olivaceus, inhabiting the Sanriku coastal waters, the concentration ratios of Ca and Sr in otoliths of juvenile fishes being cultivated for releasing to the regions, and those of adult fishes captured in both the Sanriku area (Aomori, Iwate and Miyagi) and Shizuoka prefecture coastal regions (as a comparison) were analysed using a particle induced X-ray emission (PIXE) technique. The Sr/Ca ratios of otoliths taken from juvenile Japanese flounders had significant differences between Sanriku and Shizuoka sea-farming groups. The differences in otolith Sr/Ca ratios between Sanriku and Shizuoka sea-farming stations would thus differentiate flounder populations. No significant difference in otolith Sr/Ca ratios was observed among the Sanriku group. However, the values for Aomori group formed by small fishes in the Sanriku group seemed to be lower in proportion to their body size. Therefore, genetic characteristics of the juvenile Japanese flounder being reared at the sea-farming stations in Iwate and Miyagi prefectures are possibly different from those at an Aomori station. On the other hand, statistically significant differences in the otolith Sr/Ca ratios among Aomori, Iwate Miyagi and Shizuoka groups were found in the adult Japanese flounder. That is, higher values for the otolith Sr/Ca ratios were found in the groups inhabiting in the northern regions. The differences in otolith Sr/Ca ratios among these groups probably indicate that there are differences in the fish populations among these sample sites. (author)

  7. Phase difference between calcification and organic matrix formation in the diurnal growth of otoliths in rainbow trout, Salmo gairdneri

    International Nuclear Information System (INIS)

    The relative role of calcium and organic matrix deposition in the formation of daily increments in otoliths was studied in in vitro preparations of otolith-containing sacculi of rainbow trout, Salmo gairdneri. Sacculi were incubated in a Ringer solution containing both 45Ca and 3H-glutamic acid for 2 hours at 6-h intervals throughout a 24-h period and then the uptake of these isotopes was determined for both otolith and saccular tissue fractions. Serum calcium and sodium concentrations were also analyzed for diurnal variations. Serum calcium concentrations varied diurnally by 8% in a single phasic pattern, reaching a peak at dusk (1600 h) and a nadir at night (2200 h), while sodium concentrations remained almost constant throughout a 24-h period. Diurnal variation in the otolith's uptake of calcium and glutamic acid showed discrete, antiphasic cycles. The rate of calcium uptake varied in a pattern closely resembling that of serum calcium (the peak at 1600 h and the nadir at 2200 h); glutamic acid uptake remained almost constant during the daytime and peaked at night (2200 h). The results indicate that in rainbow trout daily increments of otoliths are formed by the antiphasic deposition of calcium and organic matrix

  8. On the role of the central nervous system in regulating the mineralisation of inner-ear otoliths of fish.

    Science.gov (United States)

    Anken, Ralf H

    2006-12-01

    Stato- or otoliths are calcified structures in the organ of balance and equilibrium of vertebrates, the inner ear, where they enhance its sensitivity to gravity. The compact otoliths of fish are composed of the calcium carbonate polymorph aragonite and a small fraction of organic molecules. The latter form a protein skeleton which determines the morphology of an otolith as well as its crystal lattice structure. This short review addresses findings according to which the brain obviously plays a prominent role in regulating the mineralisation of fish otoliths and depends on the gravity vector. Overall, otolith mineralisation has thus been identified to be a unique, neuronally guided biomineralisation process. The following is a hypothetical model for regulation of calcification by efferent vestibular neurons: (1) release of calcium at tight junctions in the macular epithelia, (2) macular carbonic anhydrase activity (which in turn is responsible for carbonate deposition), (3) chemical composition of matrix proteins. The rationale and evidence that support this model are discussed. PMID:17180502

  9. FUNCTION-MORPHOLOGICAL Investigations of Fish Inner Ear Otoliths as Basis for Interpretation of Human Space Sickness

    Science.gov (United States)

    Edelmann, Elke

    2002-02-01

    In man, altered gravity may lead to a vestibular dysfunction causing space motion sickness. A hypothesis was developed, according to which asymmetric inner ear statoliths might be the morphological basis of space sickness. The animal model, fish, revealed further information: inner ear "stone" (otolith) growth is dependent on the amplitude and the direction of gravity, regulated by a negative feedback mechanism. The present study was focused on the question, where the regulation centre of adaptive otolith growth may be situated. Therefore, the vestibular nerve was unilaterally transected in neonate swordtail fish ( Xiphophorus helleri). As growth marker, the calcium tracer alizarin-complexone was used. It was found that otolith growth had ceased on the operated head sides indicating that the brain is significantly involved in regulating otolith growth. About 2 weeks after nerve transection, otoliths had regained normal growth, probably due to nerve regeneration. Concerning fish, it has now to be tested, if this regeneration is affected by altered gravity, e.g. in a long-term experiment on the International Space Station. Regarding mammals, it has to be proved if asymmetric statoliths are the basis of kinetosis and whether or not the mammalian brain has an effect on statolith growth in the course of compensating altered gravity.

  10. Up-Down Chair: A novel mechatronic device to assess otolith function in patients with vestibular disorders.

    Science.gov (United States)

    Luciani, Lorenzo Bassi; Martelli, Dario; Monaco, Vito; Genovese, Vincenzo; Micera, Silvestro

    2016-03-01

    This paper describes a novel mechatronic platform, named "Up-Down Chair" (UDC), aimed at investigating otolith function in patients with vestibular disorders. The UDC was designed to provide a wide range of repeatable and controllable vertical oscillations of the head whose kinematic features match those encountered during daily activities. The following parameters were assessed to characterize the performance of the UDC: accordance between expected and measured kinematics in both loaded and unloaded conditions; Dynamic Visual Acuity (DVA) of a group of 15 healthy subjects who were asked to identify a set of Snellen optotypes while being repeatedly moved at different perturbation intensities. Results revealed a good agreement between expected and measured kinematic patterns, and excellent reliability of DVA assessed across enrolled participants. In addition, we observed that the proposed paradigm was effective in inducing oscillopsia in enrolled subjects and that the frequency of the oscillation significantly induced blurred vision during the experimental tests. The UDC appears to be usable as a complementary vestibular clinical test to investigate the effects of therapeutic treatments while applying a wide range of physiological stimuli compatible with those encountered during daily activities. PMID:26806396

  11. Ecological study of the migration of eel by synchrotron radiation induced X-ray fluorescence imaging of otoliths

    International Nuclear Information System (INIS)

    Synchrotron radiation-induced X-ray fluorescence imaging is suitable for determining the distribution of trace elements in fish otoliths. The Sr/Ca ratio in an otolith is an indicator of salinity changes and can be used to clarify the migration history of the eel, a catadromous fish. The otoliths of eel collected from the Tone and Elbe rivers exhibited a typical catadromous pattern, i.e. birth and breeding occurred in the ocean, but the remainder of their lives was spent in fresh water. In contrast, eels from the East China Sea and North Sea exhibited an unusual sea-locking phenomenon, as they appear to have remained in marine habitats throughout their lives. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. Ecological study of the migration of eel by synchrotron radiation induced X ray fluorescence imaging of otoliths

    Science.gov (United States)

    Nakai, Izumi; Iwata, Raita; Tsukamoto, Katsumi

    1999-01-01

    Synchrotron radiation-induced X-ray fluorescence imaging is suitable for determining the distribution of trace elements in fish otoliths. The Sr/Ca ratio in an otolith is an indicator of salinity changes and can be used to clarify the migration history of the eel, a catadromous fish. The otoliths of eel collected from the Tone and Elbe rivers exhibited a typical catadromous pattern, i.e. birth and breeding occurred in the ocean, but the remainder of their lives was spent in fresh water. In contrast, eels from the East China Sea and North Sea exhibited an unusual sea-locking phenomenon, as they appear to have remained in marine habitats throughout their lives.

  13. Coupling otolith microstructure analysis and hydrographic backtracking suggests a mechanism for the 2000s North Sea herring recruitment failure

    DEFF Research Database (Denmark)

    Ross, Stine Dalmann; Payne, Mark; Worsøe Clausen, Lotte; Nash, Richard D.M.

    2012-01-01

    The North Sea autumn spawning herring (Clupea harengus) has, since the 2002 year class, shown an unprecedented sequence of ten years of sharply reduced recruitment, in spite of a high spawning biomass and low fishing mortality. Recent work has identified this reduction in recruitment level (or st...... demonstrates how coupling two different techniques (otolith microstructure analysis and hydrographic modelling) can yield unique insights into fish ecology......The North Sea autumn spawning herring (Clupea harengus) has, since the 2002 year class, shown an unprecedented sequence of ten years of sharply reduced recruitment, in spite of a high spawning biomass and low fishing mortality. Recent work has identified this reduction in recruitment level (or....... Individual larval growth rates, averaged over the 30 days prior to capture, were estimated for 200 larval otoliths from four different years using a model‐based analysis of the ring widths. The otolith measurements were complemented with additional information derived from hydrographic backtracking models (e...

  14. Short-term clearing of opaque otoliths from larval fish Transparentación de otolitos de larvas de peces

    Directory of Open Access Journals (Sweden)

    César Flores Coto

    2005-06-01

    Full Text Available A simple technique for otolith of larval fishes is described. After fixing the otolith with some resin and drying, lift one edge of the resin and add 1-2 drops of xylene. The otolith becomes transparent and allows counting the growth rings before the xylene evaporates.Se describe una técnica sencilla para transparentar otolitos de larvas de peces. Después de fijar los otolitos con alguna resina y dejar secar, se levanta la resina en algún punto y se agrega 1-2 gotas de Xilol. El otolito se transparenta y permite contar los anillos de crecimiento, antes de que el xilol se evapore.

  15. Stable lead isotope ratios from distinct anthropogenic sources in fish otoliths: a potential nursery ground stock marker.

    Science.gov (United States)

    Spencer, K; Shafer, D J; Gauldie, R W; DeCarlo, E H

    2000-11-01

    Variations measured in the lead (Pb) stable isotope ratios in otoliths of juvenile tropical reef fish Scarus perspiculatus, Abudefduf abdominalis and Dascyllus albisella reflect mixing of anthropogenic lead from the Kaneohe Bay watershed and 'background' lead characteristic of the adjacent ocean. The otoliths and water samples collected in a transect across the bay demonstrated nearly identical Pb isotopic trends. The Pb isotopic composition of the watershed has a low 206Pb/204Pb signature primarily reflecting past combustion of tetra-ethyl Pb additive in fuels. Ocean water not contaminated by this watershed signature has a different, high 206Pb/204Pb isotopic composition, similar to previously measured Asian anthropogenic aerosols and natural eolian dusts, where the anthropogenic signal dominates. Where a history of past anthropogenic Pb contamination exists, it may be possible to use the ratios of Pb stable isotopes in fish otoliths to reconstruct the nursery grounds of fish. PMID:11118937

  16. Isotopic signatures of otoliths and the stock structure of canary rockfish along the Washington and Oregon coast

    International Nuclear Information System (INIS)

    Highlights: ► Otoliths of 120 canary rockfish were analyzed for δ18O and δ13C. ► δ18O and δ13C values of the otoliths ranged from −0.2‰ to +1.7‰ and −5.4‰ to −1.4‰. ► No separation was observed from the isotopic data and δ18O vs. δ13C correlation. ► No significant difference was computed between WA and OR samples especially in δ13C. ► Canary rockfish may belong to a single spawning stock or population coast-wide. - Abstract: Canary rockfish are one of the commercially important rockfish species along the US Pacific coast. Yet little is known about their life history and stock structure. In this study 120 canary rockfish otoliths were collected from waters off the Washington and Oregon coast and subjected to stable O and C isotope (δ18O and δ13C) analyses. One powder sample was taken from the nucleus of each otolith, and the other from the 5th annual ring. Data from otolith nuclei can provide information on the natal sources and spawning stock separations, while data from age-1 to age-5 may indicate changes in fish habitat. Overall the δ18O values in otoliths of canary rockfish ranged from −0.2‰ to +1.7‰, whereas δ13C values of the same samples ranged from −5.4‰ to −1.4‰. The isotopic data and correlation of δ18O versus δ13C did not show clear separation between Washington and Oregon samples, similar to those for a previous study on yelloweye rockfish from the same region. These results suggest that canary rockfish may belong to a single spawning stock or population along the Washington and Oregon coast

  17. Ultrastructure of lamellae, mineral and matrix components of fish otolith twinned aragonite crystals: implications for estimating age in fish.

    Science.gov (United States)

    Gauldie, R W

    1999-05-01

    Atomic force microscopy (AFM) of the crystalline ultrastructure of otoliths fromPagrus major(Sparidae),Macruronus novaezelandiae(Merlucciidae),Oncorhynchus tshawytscha(Salmonidae),Sebastes alutus(Scorpaenidae), andHoplostethus atlanticus(Trachichthyidae) showed regular deposition of lamellae in the size range 13-490 nm. The orientation of lamellae in the {010} plane was the same as lamellae in crystals of mineral aragonite. Lamellae in mineral aragonite were in the size range 15-45 nm. Lamellae observed in the otolith ofM. novaezelandiaeby transmission electron microscopy showed a range of widths (25-225 nm) similar to lamellae observed by AFM. The observed lamella widths were in the size range that has been described for sub-daily and daily microincrements in otoliths. Observed lamellae widths were also in the size range of alpha-recoil trajectories of(222)Rn and provide a potential diffusion sink correction for the(222)Rn losses in radionuclide method of ageing otoliths. Comparison of the orientations of lamellae to templates based on the Bragg unit cell structure of twinned aragonite indicated that the lamellae resulted from polysynthetic twinning on the {010} aragonite crystal face. Additional cyclic twinning occurred on the {110} face of the aragonite crystal and sometimes led to pseudohexagonal crystals, whose sizes were orders of magnitude larger than lamellae. The organic matrix of the otolith was visible by atomic force and transmission electron microscopy at the nanometer level of resolution, but the organic matrix was confined to the {110} twinning plane of symmetry of the otolith crystal. PMID:18627853

  18. Elemental composition of otoliths from migrating chum salmon, Oncorhynchus keta, captured at the Kitakami river and Ishinomaki Bay

    International Nuclear Information System (INIS)

    The elemental composition (Ca, Sr, Zn and Fe) of otoliths from migrating chum salmon, Oncorhynchus keta, captured at the Kitakami river and Ishinomaki Bay was analyzed to understand the migratory history using a particle induced X-ray emission (PIXE) technique. The Sr/Ca ratio of salmon otoliths was lower (less than 1 x 10-3) in the portion formed in a freshwater environment and higher (approximately 4.8 x 10-3) in a sea water environment. When the fish migrated from sea water into a freshwater environment, the otoliths' Sr/Ca ratios significantly increased. The highest values were found in the fish captured at the lower part of the Kitakami river (about 20 km upriver from the mouth). The values from the fish captured at the upper part of the Kitakami river (about 200 km upriver from the mouth) were also not less than those of the fish captured at Ishinomaki Bay. Abnormally high otolith Sr/Ca ratios for these upriver-migrating fish, when compared to the values from non-migrating salmon inhabiting stable environmental (salinity and temperature) conditions, provided evidence that they were stressed. No significant changes in the otoliths' Zn/Ca ratios were found, while these values were inversely proportional to the Sr/Ca ratios. However, a rapid drop in the Zn/Ca ratio and an increase in the Sr/Ca ratio was observed in some individuals in which higher values for the Fe/Ca were found. These results suggest that these otolith parameters don't exactly reflect the salinity and temperature history in upriver-migrating chum salmon because the physiological mechanism of incorporation of Sr, Zn and Ca within the otolith of those fish is abnormal, though for fish in non-stressful conditions the Sr/Ca and the Zn/Ca ratios in otoliths are effective indices for predicting the history of environmental conditions experienced by the fish in the past. Regarding the relationship between the Sr/Ca and the Zn/Ca ratios, and also the Fe/Ca ratio, there is a possibility that they are

  19. Uptake of Trace Elements in Aragonitic Otoliths of an Estuarine Dependent Fish, Spotted Seatrout, from surface waters of Chesapeake Bay.

    Science.gov (United States)

    Dorval, E.; Jones, C.; Hannigan, R.; Sako, A.

    2002-05-01

    Seagrass beds in Chesapeake Bay are critical habitats for early life stages of Spotted seatrout, {\\Cynoscion nebulosus}. Spotted seatrout spawn in surface waters in the Bay during late spring and thereafter their larvae settle in seagrass beds where the juveniles spend three to four months. These habitats provide refuge and food for larvae and juveniles, influencing growth, mortality, and survival rates. Identification of essential seagrass habitats for estuarine-dependent fish is of primary importance given the current decline in habitat quality. We hypothesized that the geochemistry of surface waters in Chesapeake Bay is different along both the latitudinal and longitudinal gradients, and that we could use trace elements in otoliths as a natural tag to differentiate survivors among seagrass beds. We investigated the relationship between water and otolith trace element chemistry and we present here some preliminary results. From July to September 2001 we collected surface waters during spring tide from seagrass beds and around the mouth of the Potomac, Rappahannock, and York river. Waters were filtered through a 0.45 uM filter and acidified to pH < 2 with ultrapure nitric acid. In September, we collected juvenile fish in seagrass beds along the Western and Eastern shores, Tangier and Smith Islands. From each individual fish one sagittal otolith was extracted, cleaned with milli-Q water, soaked for 5 minutes in ultrapure hydrogen peroxide, rinsed, and sonicated. All dried and cleaned otoliths were dissolved in ultrapure nitric acid. We used trace metal clean procedures to process both water and otoliths and trace elements were measured by sector field ICP-MS. Both waters and otoliths showed distinct chemical signatures among seagrass beds, and samples could be classified with high accuracy to their respective sites of collection. For most seagrass beds Ba/Ca, Rb/Ca, V/Ca showed inverse relationship between water and otolith whereas Sr/Ca was positively correlated

  20. Defining fish nursery habitats: an application of otolith elemental fingerprinting in Tampa Bay, Florida

    Science.gov (United States)

    Ley, Janet A.; McIvor, Carole C.; Peebles, Ernst B; Rolls, Holly; Cooper, Suzanne T.

    2009-01-01

    Fishing in Tampa Bay enhances the quality of life of the area's residents and visitors. However, people's desire to settle along the Bay's shorelines and tributaries has been detrimental to the very habitat believed to be crucial to prime target fishery species. Common snook (Centropomus undecimalis) and red drum (Sciaenops ocellatus) are part of the suite of estuarine fishes that 1) are economically or ecologically prominent, and 2) have complex life cycles involving movement between open coastal waters and estuarine nursery habitats, including nursery habitats that are located within upstream, low-salinity portions of the Bay?s tidal tributaries. We are using an emerging microchemical technique -- elemental fingerprinting of fish otoliths -- to determine the degree to which specific estuarine locations contribute to adult fished populations in Tampa Bay. In ongoing monitoring surveys, over 1,000 young-of-the-year common snook and red drum have already been collected from selected Tampa Bay tributaries. Using laser ablation-inductively coupled plasma - mass spectrometry (LA-ICP-MS), we are currently processing a subsample of these archived otoliths to identify location-specific fingerprints based on elemental microchemistry. We will then analyze older fish from the local fishery in order to match them to their probable nursery areas, as defined by young-of-the-year otoliths. We expect to find that some particularly favorable nursery locations contribute disproportionately to the fished population. In contrast, other nursery areas may be degraded, or act as 'sinks', thereby decreasing their contribution to the fish population. Habitat managers can direct strategic efforts to protect any nursery locations that are found to be of prime importance in contributing to adult stocks.

  1. Fish otolith geochemistry, environmental conditions and human occupation at Lake Mungo, Australia

    Science.gov (United States)

    Long, Kelsie; Stern, Nicola; Williams, Ian S.; Kinsley, Les; Wood, Rachel; Sporcic, Katarina; Smith, Tegan; Fallon, Stewart; Kokkonen, Harri; Moffat, Ian; Grün, Rainer

    2014-03-01

    Fish otoliths from the Willandra Lakes Region World Heritage Area (south-western New South Wales, Australia) have been analysed for oxygen isotopes and trace elements using in situ techniques, and dated by radiocarbon. The study focused on the lunettes of Lake Mungo, an overflow lake that only filled during flooding events and emptied by evaporation, and Lake Mulurulu, which was part of the running Willandra Creek system. Samples were collected from two different contexts: from hearths directly associated with human activity, and isolated surface finds. AMS radiocarbon dating constrains the human activity documented by five different hearths to a time span of less than 240 years around 19,350 cal. BP. These hearths were constructed in aeolian sediments with alternating clay and sand layers, indicative of fluctuating lake levels and occasional drying out. The geochemistry of the otoliths confirms this scenario, with shifts in Sr/Ca and Ba/Ca marking the entry of the fish into Lake Mungo several years before their death, and a subsequent increase in the δ18O by ˜4‰ indicating increasing evaporation of the lake. During sustained lake-full conditions there are considerably fewer traces of human presence. It seems that the evaporating Lake Mungo attracted people to harvest fish that might have become sluggish through oxygen starvation in an increasingly saline water body (easy prey hypothesis). In contrast, surface finds have a much wider range in radiocarbon age as a result of reworking, and do not necessarily indicate evaporative conditions, as shown by comparison with otoliths from upstream Lake Mulurulu.

  2. Otolith shape analysis as a tool for stock identification of the southern blue whiting, Micromesistius australis

    Directory of Open Access Journals (Sweden)

    Javier Leguá

    2013-07-01

    Full Text Available The southern blue whiting, Micromesistius australis (Norman, 1937, is an important demersal resource associated with the slope and continental shelf of southern Chile, Argentina and the Malvinas/Falkland Islands. Recent studies have reported schools of adult fish from Atlantic waters migrating along the southern Chilean coast in mid-winter, moving northwards to spawn in August (47°-51°S, and then returning to Atlantic waters, presumably to feed. The migratory pattern suggests the presence of one or more stock units associated with the South American coast. In the present study, "otolith morphometry" is used to determine the stock structure of M. australis based on applications of basic size descriptors (SDs (area, perimeter and otolith size, shape indices (SIs (circularity, squareness, shape factor, roundness, ellipticity, and normalised elliptical Fourier descriptors (NEFDs. Samples were collected during the winter and spring of 2010, during the reproductive period, in the economic zone of southern Chile (36°-57°S, in the Pacific Ocean and around the Falkland Islands economic zone (50°-52°S in the Atlantic Ocean. Analyses were conducted to include the effects of size, sex and age. A stepwise canonical discriminant analysis showed that fish were successfully discriminated with SDs, SIs and NEFDs. In this analysis, 86.4% and 70.1% of the fish were correctly classified as belonging to the Atlantic and Pacific stocks, respectively. A multivariate analysis of variance showed that the mean values of the NEFDs, SDs, and SIs did not vary significantly between sexes within areas (P > 0.05, but varied significantly between the Pacific and Atlantic oceans (P < 0.05. These results highlighted that otolith shape analysis can be a useful tool to evaluate the potential level of mixing in feeding areas where both stocks, the Pacific and Atlantic units, are expected to co-occur.

  3. A Multiagent System for Edge Detection and Continuity Perception on Fish Otolith Images

    Science.gov (United States)

    Guillaud, Anne; Troadec, Herve; Benzinou, Abdesslam; Le Bihan, Jean; Rodin, Vincent

    2002-12-01

    We present an algorithm for fish otolith growth ring detection using a multiagent system. Up to now, the identification of growth rings, for age estimation, is routinely achieved by human readers, but this task is tedious and depends on the reader subjectivity. One of the major problems encountered during an automatic contour detection is the lack of ring continuity perception. We present an approach to improve this continuity perception based on a 2D reconstruction of rings using a multiagent system. The originality of the approach is to use local edge detection achieved by agents and combine it with continuity perception that active contours allow.

  4. A Multiagent System for Edge Detection and Continuity Perception on Fish Otolith Images

    Directory of Open Access Journals (Sweden)

    Anne Guillaud

    2002-07-01

    Full Text Available We present an algorithm for fish otolith growth ring detection using a multiagent system. Up to now, the identification of growth rings, for age estimation, is routinely achieved by human readers, but this task is tedious and depends on the reader subjectivity. One of the major problems encountered during an automatic contour detection is the lack of ring continuity perception. We present an approach to improve this continuity perception based on a 2D reconstruction of rings using a multiagent system. The originality of the approach is to use local edge detection achieved by agents and combine it with continuity perception that active contours allow.

  5. The use of otolith microstructure to estimate age in adult Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Hinrichsen, H.H.; Fey, D.P.;

    2010-01-01

    be tightly coupled to the annual cycle in environmental temperature at a depth of 30–60 m, where G. morhua predominantly reside. Between 135 and 200 increments occurred within the different zones, with a non-significant trend towards lower increment numbers and widths with distance from the primary...... primordium of the otolith. Increment formation apparently ceased at temperatures <5–6° C, but growth during the cold months corresponded closely with estimated growth rates. The increment patterns seemed to reflect annual cycles in environmental temperature, and the count of the increment cycles may thus be...... a promising tool for the determination of the true age of Baltic G. morhua....

  6. FLUCTUATING ASYMMETRY IN THE OTOLITH WIDTH AND LENGTH OF ADULT TELEOST (Beryx splendens LOWE, 1834 (FAMILY: BERCIDAE COLLECTED FROM THE ARABIAN SEA COASTS OF SULTANATE OF OMAN

    Directory of Open Access Journals (Sweden)

    H.K. Albusaidi

    2010-10-01

    Full Text Available Fluctuating asymmetry was described for the otolith width and length of adult teleost Beryx splendens. The results showed that the level of asymmetry of the otolith width was the highest among the two asymmetry values obtained for the otolith of B. splendens. For the otolith width character, the results showed that the level of asymmetry at its highest value in fish ranging in length between 191–200 mm and in its lowest value in fish ranging in length between 121–180 mm. For the otolith length, the highest value of asymmetry is noticed in fish ranging in length between 231–244 mm and the lowest value in fish within the length of 121–190 mm. The possible cause of the asymmetry in this species has been discussed in relation to different pollutants and their presence in the area. No trend of increase in the asymmetry values with the fish length was noticed for the otolith width, but there is a weak trend of increase with the fish length in case of otolith length character.

  7. High resolution micromill sampling for analysis of fish otoliths by ICP-MS: effects of sampling and specimen preparation on trace element fingerprints.

    Science.gov (United States)

    Arslan, Zikri; Secor, David H

    2008-09-01

    Otoliths are calcified structures in the head of fish that record environmental information about fish's life history. Gathering the elemental information from the core of an otolith corresponding to the juvenile period of fish's life is critical to discriminate the adult fish to their natal habitats reliably. A high resolution micromill has been used to isolate the otolith core from a whole otolith for elemental analysis. The effects of micromilling procedures (e.g., sectioning, embedding and drilling) on contamination to otolith trace element levels were examined using paired blackfin tuna (Thunnus atlanticus) otoliths. Otoliths were decontaminated by dilute hydrogen peroxide and nitric acid throughout to remove surface contamination. A preconcentration procedure was used to determine the trace elements from the small core material by ICP-MS. It was found that micromilling procedures introduce significant contamination to otoliths, especially for Al, Cu, Pb and Zn. The sectioning procedure caused significant contamination for Co and Cu, while the embedding procedure resulted in contamination for nearly all trace elements (Al, Cd, Co, Cu, Ga, Mn, Ni, Pb, V and Zn). The combined sectioning, embedding and drilling procedure also resulted in contamination for most trace elements. Despite the contamination across all procedural steps, the decontamination procedure effectively removed the surface contamination with the exception of Pb and Zn. Bias (e.g., residual contamination) on Pb was small in comparison to overall concentration of Pb expected to occur in fish otoliths, therefore, its effect may be minor in discriminating individuals. Bias on Zn was larger that could limit its application in discriminating individuals. PMID:18640714

  8. Distribution of otoliths in surficial sediments of the U.S. Atlantic Continental Shelf and slope and potential for reconstructing Holocene fish stocks

    Science.gov (United States)

    Elder, Kathryn L.; Jones, Glenn A.; Bolz, George

    1996-06-01

    We examined more than 1100 surface sediment samples from the Atlantic continental margin of the United States to determine the feasibility of using fossil fish otoliths as diagnostic tools in reconstructing paleoenvironments and latitudinal distribution of fish stocks during the Holocene. Although 63% of the 1107 samples collected were from shelf areas (<140 m), the total number of shelf-derived otoliths represents only 0.3% of the entire sampled assemblage. The majority of otoliths occurred on the continental slope (400-2000 m), with a maximum concentration in sediments at 500 to 600-m water depth. Otoliths of the most commonly occurring species, Ceratoscopelus maderensis, exhibit a marked distributional boundary just south of Cape Hatteras, North Carolina (33°N), which mimics the distribution of their living counterparts. North of this boundary, C. maderensis constitutes greater than 70% of the preserved otolith assemblage, whereas more southerly regions contain no otoliths of this species. Although C. maderensis typically migrates diurnally over a depth of 300-600 m, otoliths taken from live-captured C. maderensis exhibit Δ14C values comparable to that of the dissolved inorganic carbon (DIC) of surface seawater in the study area. Accelerator mass spectrometry radiocarbon analyses of cooccurring otoliths and planktonic foraminifera from a sediment core collected south of Martha's Vineyard (40°15'N 70°51'W, 265 m) demonstrate temporal concordance throughout the Holocene. Otoliths appear to be viable, underutilized paleoceanographic tools. Specimens are found in sufficient abundance to permit temporal reconstructions of the distribution of C. maderensis and potentially several other icthyospecies along the U.S. Atlantic continental margin.

  9. Micro-ERDA, micro-RBS and micro-PIXE techniques in the investigation of fish otoliths

    Energy Technology Data Exchange (ETDEWEB)

    Huszank, R. [Institute of Nuclear Research of the Hungarian Academy of Sciences, P.O. Box 51, H-4001 Debrecen (Hungary)], E-mail: huszank@atomki.hu; Simon, A. [Institute of Nuclear Research of the Hungarian Academy of Sciences, P.O. Box 51, H-4001 Debrecen (Hungary); Szilagyi, E. [KFKI Research Institute for Particle and Nuclear Physics, P.O. Box 49, H-1525 Budapest (Hungary); Keresztessy, K. [Department of Fish Culture, Institute of Environmental and Landscape Management, Szent Istvan University, Pater K.u.1, H-2103 Goedoello (Hungary); Kovacs, I. [KFKI Research Institute for Particle and Nuclear Physics, P.O. Box 49, H-1525 Budapest (Hungary)

    2009-06-15

    Elemental distribution in the otolith of the fresh water fish burbot (Lota lota L.) collected in Hungary was measured with Elastic Recoil Detection Analysis (ERDA), Rutherford Backscattering Spectrometry (RBS) and as a complementary technique, Particle-Induced X-ray Emission (PIXE) with a focussed ion beam of 1.5 x 1.5 {mu}m{sup 2} spot size. The organic- and inorganic-rich regions of the otolith are distinguished and they are presented as hydrogen and calcium maps at depth regions of 0-70, 70-140 and 140-210 nm. The textured surface of the sample and its porosity were characterized from the effect on the RBS spectra. The oxygen and carbon PIXE elemental maps can also be used to identify the organic- and inorganic-rich regions of the otolith. The calcium map was found to be more homogeneous because the otolith structure is averaged in a larger depth. The trace elements Fe, Zn and Sr were detected only in very low concentration by micro-PIXE.

  10. Micro-ERDA, micro-RBS and micro-PIXE techniques in the investigation of fish otoliths

    Science.gov (United States)

    Huszank, R.; Simon, A.; Szilágyi, E.; Keresztessy, K.; Kovács, I.

    2009-06-01

    Elemental distribution in the otolith of the fresh water fish burbot ( Lota lota L .) collected in Hungary was measured with Elastic Recoil Detection Analysis (ERDA), Rutherford Backscattering Spectrometry (RBS) and as a complementary technique, Particle-Induced X-ray Emission (PIXE) with a focussed ion beam of 1.5 × 1.5 μm 2 spot size. The organic- and inorganic-rich regions of the otolith are distinguished and they are presented as hydrogen and calcium maps at depth regions of 0-70, 70-140 and 140-210 nm. The textured surface of the sample and its porosity were characterized from the effect on the RBS spectra. The oxygen and carbon PIXE elemental maps can also be used to identify the organic- and inorganic-rich regions of the otolith. The calcium map was found to be more homogeneous because the otolith structure is averaged in a larger depth. The trace elements Fe, Zn and Sr were detected only in very low concentration by micro-PIXE.

  11. Exposure histories derived from selenium in otoliths of three cold-water fish species captured downstream from coal mining activity.

    Science.gov (United States)

    Friedrich, Lisa A; Orr, Patricia L; Halden, Norman M; Yang, Panseok; Palace, Vince P

    2011-10-01

    Establishing exposure to contaminants within a given environment is often difficult for fish species with large home ranges. Chemical analyses of muscle or visceral tissue are useful indicators of recent exposure, but depuration, metabolic transformation, and tissue redistributions can alter temporal resolution. Otoliths are metabolically stable and thus provide complete chemical records within their calcified tissues that, when coupled to the annular structure, can provide temporal resolution for exposure to trace metals. Otoliths from bull trout, cutthroat trout, and mountain whitefish from an area rich in seleniferous soils and with active coal mining activity were analyzed for selenium to determine any history of exposure to elevated levels of selenium. Selenium concentrations in otolith primordia tended to be low, indicating that these fish emerged in low selenium areas. Later life stages showed peaks of high Se concentrations, suggesting that individuals moved into areas of increased selenium later in life. Individuals captured from the same area had a wide variety of selenium exposure profiles, indicating that these fish do not move en masse into and out of high-selenium areas. Year-to-year variability of selenium exposure patterns within an otolith suggests inconsistent utilization of high- and low-selenium areas by the individual. The inconsistent exposure profiles for these fish, in addition to their home range of tens of kilometres, indicate that soft tissue concentrations, while useful indicators of recent exposure, cannot be relied upon to provide a life history recording of exposure. PMID:21899824

  12. Micro-ERDA, micro-RBS and micro-PIXE techniques in the investigation of fish otoliths

    International Nuclear Information System (INIS)

    Elemental distribution in the otolith of the fresh water fish burbot (Lota lota L.) collected in Hungary was measured with Elastic Recoil Detection Analysis (ERDA), Rutherford Backscattering Spectrometry (RBS) and as a complementary technique, Particle-Induced X-ray Emission (PIXE) with a focussed ion beam of 1.5 x 1.5 μm2 spot size. The organic- and inorganic-rich regions of the otolith are distinguished and they are presented as hydrogen and calcium maps at depth regions of 0-70, 70-140 and 140-210 nm. The textured surface of the sample and its porosity were characterized from the effect on the RBS spectra. The oxygen and carbon PIXE elemental maps can also be used to identify the organic- and inorganic-rich regions of the otolith. The calcium map was found to be more homogeneous because the otolith structure is averaged in a larger depth. The trace elements Fe, Zn and Sr were detected only in very low concentration by micro-PIXE.

  13. Connectivity between migrating and landlocked populations of a diadromous fish species investigated using otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Ingrid Tulp

    Full Text Available Smelt Osmerus eperlanus has two different life history strategies in The Netherlands. The migrating population inhabits the Wadden Sea and spawns in freshwater areas. After the closure of the Afsluitdijk in 1932, part of the smelt population became landlocked. The fresh water smelt population has been in severe decline since 1990, and has strongly negatively impacted the numbers of piscivorous water birds relying on smelt as their main prey. The lakes that were formed after the dike closure, IJsselmeer and Markermeer have been assigned as Natura 2000 sites, based on their importance for (among others piscivorous water birds. Because of the declining fresh water smelt population, the question arose whether this population is still supported by the diadromous population. Opportunities for exchange between fresh water and the sea are however limited to discharge sluices. The relationship between the diadromous and landlocked smelt population was analysed by means of otolith microchemistry. Our interpretation of otolith strontium ((88Sr patterns from smelt specimens collected in the fresh water area of Lake IJsselmeer and Markermeer, compared to those collected in the nearby marine environment, is that there is currently no evidence for a substantial contribution from the diadromous population to the spawning stock of the landlocked population.

  14. Partial migration of grey mullet (Mugil cephalus) on Australia's east coast revealed by otolith chemistry.

    Science.gov (United States)

    Fowler, Ashley M; Smith, Shannen M; Booth, David J; Stewart, John

    2016-08-01

    Partial migration affects the ecology and evolution of animal populations, and is an important consideration for the management of harvested species, yet the phenomenon is understudied in fish. We provide the first insights into partially diadromous migration of grey mullet (Mugil cephalus) in Australia by examining the otolith chemistry of old individuals (aged 7-10 years) from two regions on the east coast. Strontium and Barium concentrations were measured across the otolith using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and indicated considerable diversity in migratory histories among individuals. Only 15% of individuals made repeated movements from estuaries to the marine environment, consistent with the annual spawning run in the region. The remainder either made irregular movements between salinity environments (70%), or resided in estuaries or fresh water for their entire life following the early juvenile stage (15%). The patterns are consistent with 'skipped spawning' partial migration, where a proportion of the mature population forgoes spawning each year. If confirmed, the behavior may afford the east coast population of M. cephalus some resilience to fishing pressure on the annual spawning run. PMID:27344396

  15. Comparative study on nano-mechanics and thermodynamics of fish otoliths

    International Nuclear Information System (INIS)

    Fish otolith is a kind of typical natural biomineral, which is composed of calcium carbonate and organic matrix. In fresh water carp otolith, the inorganic phase of lapillus is pure aragonite, and for asteriscus it is pure vaterite. In this research, the phase composition, phase transformation, mechanical property and solubility of lapillus and asteriscus were studied. And results showed that, the organic content of lapillus was higher than that of asteriscus; the phase-transition temperature of lapillus (aragonite–calcite) and asteriscus (vaterite–calcite) both happened between 520 and 640 °C; the nano-mechanical property of lapillus was better than that of asteriscus; the solubility of asteriscus powder was higher than that of lapillus powder. - Highlights: ► The nano-mechanical property of lapillus (aragonite) was better than that of asteriscus (vaterite). ► The phase-transition temperature of lapillus and asteriscus were both between 520 and 640 °C. ► The solubility property of asteriscus powder was better than that of lapillus powder.

  16. Connectivity between migrating and landlocked populations of a diadromous fish species investigated using otolith microchemistry.

    Science.gov (United States)

    Tulp, Ingrid; Keller, Marieke; Navez, Jacques; Winter, Hendrik V; de Graaf, Martin; Baeyens, Willy

    2013-01-01

    Smelt Osmerus eperlanus has two different life history strategies in The Netherlands. The migrating population inhabits the Wadden Sea and spawns in freshwater areas. After the closure of the Afsluitdijk in 1932, part of the smelt population became landlocked. The fresh water smelt population has been in severe decline since 1990, and has strongly negatively impacted the numbers of piscivorous water birds relying on smelt as their main prey. The lakes that were formed after the dike closure, IJsselmeer and Markermeer have been assigned as Natura 2000 sites, based on their importance for (among others) piscivorous water birds. Because of the declining fresh water smelt population, the question arose whether this population is still supported by the diadromous population. Opportunities for exchange between fresh water and the sea are however limited to discharge sluices. The relationship between the diadromous and landlocked smelt population was analysed by means of otolith microchemistry. Our interpretation of otolith strontium ((88)Sr) patterns from smelt specimens collected in the fresh water area of Lake IJsselmeer and Markermeer, compared to those collected in the nearby marine environment, is that there is currently no evidence for a substantial contribution from the diadromous population to the spawning stock of the landlocked population. PMID:23922803

  17. Strontium isotopes in otoliths of a non-migratory fish (slimy sculpin): Implications for provenance studies

    Science.gov (United States)

    Brennan, Sean R.; Fernandez, Diego P.; Zimmerman, Christian E.; Cerling, Thure E.; Brown, Randy J.; Wooller, Matthew J.

    2015-01-01

    Heterogeneity in 87Sr/86Sr ratios of river-dissolved strontium (Sr) across geologically diverse environments provides a useful tool for investigating provenance, connectivity and movement patterns of various organisms and materials. Evaluation of site-specific 87Sr/86Sr temporal variability throughout study regions is a prerequisite for provenance research, but the dynamics driving temporal variability are generally system-dependent and not accurately predictable. We used the time-keeping properties of otoliths from non-migratory slimy sculpin (Cottus cognatus) to evaluate multi-scale 87Sr/86Sr temporal variability of river waters throughout the Nushagak River, a large (34,700 km2) remote watershed in Alaska, USA. Slimy sculpin otoliths incorporated site-specific temporal variation at sub-annual resolution and were able to record on the order of 0.0001 changes in the 87Sr/86Sr ratio. 87Sr/86Sr profiles of slimy sculpin collected in tributaries and main-stem channels of the upper watershed indicated that these regions were temporally stable, whereas the Lower Nushagak River exhibited some spatio-temporal variability. This study illustrates how the behavioral ecology of a non-migratory organism can be used to evaluate sub-annual 87Sr/86Sr temporal variability and has broad implications for provenance studies employing this tracer.

  18. Comparative study on nano-mechanics and thermodynamics of fish otoliths

    Energy Technology Data Exchange (ETDEWEB)

    Dongni, Ren; Yonghua, Gao [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Qingling, Feng, E-mail: biomater@mail.tsinghua.edu.cn [Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2013-01-01

    Fish otolith is a kind of typical natural biomineral, which is composed of calcium carbonate and organic matrix. In fresh water carp otolith, the inorganic phase of lapillus is pure aragonite, and for asteriscus it is pure vaterite. In this research, the phase composition, phase transformation, mechanical property and solubility of lapillus and asteriscus were studied. And results showed that, the organic content of lapillus was higher than that of asteriscus; the phase-transition temperature of lapillus (aragonite-calcite) and asteriscus (vaterite-calcite) both happened between 520 and 640 Degree-Sign C; the nano-mechanical property of lapillus was better than that of asteriscus; the solubility of asteriscus powder was higher than that of lapillus powder. - Highlights: Black-Right-Pointing-Pointer The nano-mechanical property of lapillus (aragonite) was better than that of asteriscus (vaterite). Black-Right-Pointing-Pointer The phase-transition temperature of lapillus and asteriscus were both between 520 and 640 Degree-Sign C. Black-Right-Pointing-Pointer The solubility property of asteriscus powder was better than that of lapillus powder.

  19. Defective skeletogenesis and oversized otoliths in fish early stages in a changing ocean.

    Science.gov (United States)

    Pimentel, Marta S; Faleiro, Filipa; Dionísio, Gisela; Repolho, Tiago; Pousão-Ferreira, Pedro; Machado, Jorge; Rosa, Rui

    2014-06-15

    Early life stages of many marine organisms are being challenged by rising seawater temperature and CO₂ concentrations, but their physiological responses to these environmental changes still remain unclear. In the present study, we show that future predictions of ocean warming (+4°C) and acidification (ΔpH=0.5 units) may compromise the development of early life stages of a highly commercial teleost fish, Solea senegalensis. Exposure to future conditions caused a decline in hatching success and larval survival. Growth, metabolic rates and thermal tolerance increased with temperature but decreased under acidified conditions. Hypercapnia and warming amplified the incidence of deformities by 31.5% (including severe deformities such as lordosis, scoliosis and kyphosis), while promoting the occurrence of oversized otoliths (109.3% increase). Smaller larvae with greater skeletal deformities and larger otoliths may face major ecophysiological challenges, which might potentiate substantial declines in adult fish populations, putting in jeopardy the species' fitness under a changing ocean. PMID:24625652

  20. Spatial and temporal variability in the otolith chemistry of the Brazilian snapper Lutjanus alexandrei from estuarine and coastal environments.

    Science.gov (United States)

    Aschenbrenner, A; Ferreira, B P; Rooker, J R

    2016-07-01

    Otolith chemistry of juvenile and adult individuals of the Brazilian snapper Lutjanus alexandrei was measured to assess the utility of natural markers for investigating individual movements. Individuals were collected over a 3-year period (2010-2012) along the north-eastern coast of Brazil from both estuarine (juvenile to sub-adult stages) and coastal (sub-adult to adult stages) areas. Six elements ((7) Li, (24) Mg, (55) Mn, (59) Co, (88) Sr and (137) Ba) were measured in sectioned otoliths of L. alexandrei using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Edge composition analysis indicated that element:Ca ratios in the otoliths of juvenile and sub-adult L. alexandrei from estuaries were not significantly different among the three consecutive years (2010, 2011 and 2012), suggesting that physicochemical conditions within the nursery area investigated were temporally stable. Similarly, apart from two elements (Ba and Co), element:Ca ratios for larger L. alexandrei inhabiting coastal waters were also similar. In contrast, otolith chemistry of similar sized L. alexandrei from estuarine and coastal areas was significantly different (based on recently accreted material). Otolith Mn:Ca and Ba:Ca were both significantly higher for L. alexandrei collected in estuaries compared to fish from adjacent coastal reefs, while the opposite trend was observed for Sr:Ca. Given the pronounced differences in otolith chemistry between estuarine and coastal areas, element:Ca transects were constructed from the core to margin of the otoliths for adults (age 7+ years) collected on reefs to determine the timing of movement (ontogenetic migration) from estuarine to coastal areas. Based on observed patterns of decline for both Mn:Ca and Ba:Ca, it appears that L. alexandrei begin the move to more coastal habitats (i.e. lower element:Ca ratios) after age 2 years. The patterns observed for this species highlight the importance of conserving connectivity between

  1. RELATIONSHIPS BETWEEN FISH LENGTH AND OTOLITH LENGTH, WIDTH AND WEIGHT OF THE INDIAN MACKEREL Rastrelliger kanagurta (CUVIER, 1817 COLLECTED FROM THE SEA OF OMAN

    Directory of Open Access Journals (Sweden)

    L. A Jawad

    2011-07-01

    Full Text Available The relationships between otolith dimensions and fish size (Fish total and fork lengths for the teleost species, Rastrelliger kanagurta (Cuvier, 1817 collected from the vicinity of Muscat City at Oman Sea were examined and found to be linear. Otolith morphometric observations included length, weight and width were correlated with the total and fork lengths of the fish. Regression models relating each otolith morphometric parameter to the two fish lengths are provided. The significance of each parameter for estimating fish length was examined. The length, width and weight of otolith appeared to have the best discrimination for estimating total and fork length of fish as well as the easiest parameters to measure.

  2. Fully-automated identification of fish species based on otolith contour: using short-time Fourier transform and discriminant analysis (STFT-DA).

    Science.gov (United States)

    Salimi, Nima; Loh, Kar Hoe; Kaur Dhillon, Sarinder; Chong, Ving Ching

    2016-01-01

    Background. Fish species may be identified based on their unique otolith shape or contour. Several pattern recognition methods have been proposed to classify fish species through morphological features of the otolith contours. However, there has been no fully-automated species identification model with the accuracy higher than 80%. The purpose of the current study is to develop a fully-automated model, based on the otolith contours, to identify the fish species with the high classification accuracy. Methods. Images of the right sagittal otoliths of 14 fish species from three families namely Sciaenidae, Ariidae, and Engraulidae were used to develop the proposed identification model. Short-time Fourier transform (STFT) was used, for the first time in the area of otolith shape analysis, to extract important features of the otolith contours. Discriminant Analysis (DA), as a classification technique, was used to train and test the model based on the extracted features. Results. Performance of the model was demonstrated using species from three families separately, as well as all species combined. Overall classification accuracy of the model was greater than 90% for all cases. In addition, effects of STFT variables on the performance of the identification model were explored in this study. Conclusions. Short-time Fourier transform could determine important features of the otolith outlines. The fully-automated model proposed in this study (STFT-DA) could predict species of an unknown specimen with acceptable identification accuracy. The model codes can be accessed at http://mybiodiversityontologies.um.edu.my/Otolith/ and https://peerj.com/preprints/1517/. The current model has flexibility to be used for more species and families in future studies. PMID:26925315

  3. Oxygen isotopic distribution along the otolith growth axis by secondary ion mass spectrometry: Applications for studying ontogenetic change in the depth inhabited by deep-sea fishes

    Science.gov (United States)

    Shiao, Jen-Chieh; Itoh, Shoichi; Yurimoto, Hisayoshi; Iizuka, Yoshiyuki; Liao, Yun-Chih

    2014-02-01

    This study using tuna otoliths as working standards established a high lateral resolution and precision analysis to measure δ18Ootolith by secondary ion mass spectrometry. This analytical approach of the ion probe was applied to deep-sea fishes to reconstruct the likely depths inhabited by the fishes at different life history stages based on the measured δ18Ootolith values as a proxy of water temperature. Dramatic increases up to 5-6‰ in δ18Ootolith, representing a temperature decrease of approximately 20 °C, were detected in a blind cusk eel (Barathronus maculatus) otolith and in the otoliths of Synaphobranchus kaupii during leptocephalus metamorphosis to glass eel, inferred from the drop of otolith Sr/Ca ratios and increase of otolith growth increment width. δ18Ootolith profiles clearly divided the fish's life history into a planktonic stage in the mixed layer of the ocean and a benthic stage on the deep-sea ocean bottom. The habitat shift signal was recorded within a 150 μm width of otolith growth zone, which was too narrow to be clearly detected by mechanical drilling and conventional isotopic ratio mass spectrometry. However, variations down to -7‰ were found in δ18Ootolith profiles as the result of Cs2+ beam sputter in the core and larval portions of the otoliths. Carbon mapping by electron probe microanalyzer and staining by toluidine blue suggested abundant proteins existed in the areas with anomaly negative δ18Ootolith values, which cannot be interpreted as a habitat change but due to the isotopic fractionation by O emission from the proteins. These results implied that careful design and understanding of the chemical composition of the analytical areas or tracks on the heterogeneous otolith was essential for highly accurate and precise analysis.

  4. Otolith Trace Elemental Analyses of South American Austral Hake, Merluccius australis (Hutton, 1872) Indicates Complex Salinity Structuring on their Spawning/Larval Grounds

    OpenAIRE

    Brickle, Paul; Schuchert, Pia C.; Arkhipkin, Alexander I.; Malcolm R Reid; Randhawa, Haseeb S.

    2016-01-01

    Trace element signatures of otolith edges and cores from 335 austral hake (Merluccius autralis) were analysed using LA-ICPMS from samples collected in Chilean and Falkland Islands' waters, in order to provide potential insights into stock discrimination and migrations. Fish were caught in two locations in Chile and four locations in the south-west of the Falkland Islands Shelf. Univariate and multivariate analyses of trace element signatures in the edges of otoliths, representing adult fish, ...

  5. A novel method to develop an otolith microchemistry model to determine striped bass habitat use in the San Francisco Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Phillis, C C; Ostrach, D J; Gras, M; Yin, Q; Ingram, B L; Zinkl, J G; Weber, P K

    2006-06-14

    Otolith Sr/Ca has become a popular tool for hind casting habitat utilization and migration histories of euryhaline fish. It can readily identify habitat shifts of diadromous fish in most systems. Inferring movements of fish within estuarine habitat, however, requires a model of that accounts of the local water chemistry and the response of individual species to that water chemistry, which is poorly understood. Modeling is further complicated by the fact that high marine Sr and Ca concentrations results in a rapid, nonlinear increase in water Sr/Ca and {sup 87}Sr/{sup 86}Sr between fresh and marine waters. Here we demonstrate a novel method for developing a salinity-otolith Sr/Ca model for the purpose of reconstructing striped bass (Morone saxatilis) habitat use in the San Francisco Bay estuary. We used correlated Sr/Ca and {sup 87}Sr/{sup 86}Sr ratios measurements from adult otoliths from striped bass that experienced a range of salinities to infer striped bass otolith Sr/Ca response to changes in salinity and water Sr/Ca ratio. Otolith {sup 87}Sr/{sup 86}Sr can be assumed to accurately record water {sup 87}Sr/{sup 86}Sr because there is no biological fractionation of Sr isotopes. Water {sup 87}Sr/{sup 86}Sr can in turn be used to estimate water salinity based on the mixing of fresh and marine water with known {sup 87}Sr/{sup 86}Sr ratios. The relationship between adjacent analyses on otoliths of Sr/Ca and {sup 87}Sr/{sup 86}Sr by LA-ICP-MS and MC-ICP-MS (r{sup 2} = 0.65, n = 66) is used to predict water salinity from a measured Sr/Ca ratio. The nature of this non-linear model lends itself well to identifying residence in the Delta and to a lesser extent Suisun Bay, but does not do well locating residence within the more saline bays west of Carquinez Strait. An increase in the number of analyses would improve model confidence, but ultimately the precision of the model is limited by the variability in the response of individual fish to water Sr/Ca.

  6. Evaluation of chemical markers for age validation of western Baltic cod (Gadus morhua otoliths

    Directory of Open Access Journals (Sweden)

    Sven Stötera

    2015-11-01

    Baltic cod were intraperitoneally injected with the different chemicals and kept for 47 days in netpens. The lowest mortality and best ring formation was observed at 100mg/kg cod wet weight compared to 50 and 25mg/kg wet weight (TET only. Preliminary analysis suggests that the simultaneous injection of TET and STR decreases the visibility of TET-rings. This is probably due to a binding interaction between both markers in the body of the fish, so that less TET is bound in the otolith. The use of tetracycline hydrochloride in the concentrations of 50 mg/kg and 100 mg/kg fish were considered the most appropriate to mark Baltic cod for age validation in large-scale mark-recapture experiments. TET and STR should not be injected together.

  7. Micro-PIXE analysis of fish otoliths. Methodology and evaluation of first results for stock discrimination

    International Nuclear Information System (INIS)

    Micro-PIXE has been used to measure the trace element distribution in otoliths from several species of ocean fish, in order to investigate its possible use in stock discrimination. Trace elements detected include Sr, Fe, Mn, Ni, Zn, Cu, Se, Cd, Br, Hg and Pb. Trace elements Na, K, Cl, S and Cl were detected with the electron microprobe. The high sensitivity of PIXE demands a meticulous sample preparation procedure to avoid contamination problems. Practical problems associated with the application of the technique were investigated in detail. Preliminary results indicate that most trace elements except Sr, are present at close to the limits of detection at few ppm, but biologically significant data can be obtained for stock discrimination applications. (author)

  8. Micro-PIXE analysis of fish otoliths. Methodology and evaluation of first results for stock discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Sie, S.H. [Commonwealth Scientific and Industrial Research Organization, North Ryde, NSW (Australia). Div. of Exploration Geoscience; Thresher, R.E.

    1992-12-31

    Micro-PIXE has been used to measure the trace element distribution in otoliths from several species of ocean fish, in order to investigate its possible use in stock discrimination. Trace elements detected include Sr, Fe, Mn, Ni, Zn, Cu, Se, Cd, Br, Hg and Pb. Trace elements Na, K, Cl, S and Cl were detected with the electron microprobe. The high sensitivity of PIXE demands a meticulous sample preparation procedure to avoid contamination problems. Practical problems associated with the application of the technique were investigated in detail. Preliminary results indicate that most trace elements except Sr, are present at close to the limits of detection at few ppm, but biologically significant data can be obtained for stock discrimination applications. (author).

  9. Otolith microstructure analysis to resolve seasonal patterns of hatching and settlement in western Baltic cod

    DEFF Research Database (Denmark)

    Rehberg-Haas, Sabine; Hammer, Cornelius; Hillgruber, Nicola;

    2012-01-01

    differentiate between true annuli and secondary structures such as settlement checks. Otoliths were collected from fish off Fehmarn Island in 2008 and 2009, and were examined for macrostructural and microstructural patterns using light and scanning electron microscopy. All fish examined were age-0. Back......-calculation of hatch dates indicated hatching from April to June and from February to August in 2008 and 2009, respectively. Juveniles formed either one or two translucent rings. The first translucent ring started to form ∼3 months post-hatch and was interpreted as a settlement check, since it appeared to be a...... February and May, but were merged in those fish where settlement coincided with the seasonally formed second ring...

  10. Fine-scale oscillatory banding in otoliths from arctic charr (Salveninus alpinus) and pike (Esox lucius)

    Energy Technology Data Exchange (ETDEWEB)

    Meldrum, A. [Oak Ridge National Lab., TN (United States); Halden, N.M. [Univ. of Manitoba, Winnipeg (Canada). Dept. of Geological Sciences

    1997-12-31

    Transmission electron microscopy of otoliths from the inner ear of arctic charr and pike has revealed the presence of fine banding on the scale of several nanometers. The thickness of the bands was observed to vary in different portions of the sample, and some areas were not banded. EDS analysis could not detect chemical differences within the bands, but electron diffraction showed that the crystallographic orientation of the bands is related by a lattice mismatch. Previously, banding on the scale of 50 to 100 microns was observed by SEM in otoliths from arctic charr and was attributed to seasonal variations in growth. The fine-scale banding observed in this study, however, is unlikely to represent a daily variation. Electron diffraction from the pike samples shows that the material is composed of CaCO{sub 3} having the both the vaterite and aragonite structure, and hydrous CaCO{sub 3} was also observed. The large-scale banding previously identified by SEM was not observed in the TEM despite attempts to intersect the boundaries of the micron-sized layers. The interaction of the electron beam with the sample material was investigated by conducting several electron-irradiation experiments. The electron beam was observed to interact strongly with the sample and caused the precipitation of cubic CaO from the calcium carbonate matrix. Bright-field imaging showed the development of fine grained ({approximately} 5 nm) randomly oriented crystallites which accumulated with increasing electron dose. These initial results suggest that the precipitation of CaO is not driven by electron-beam beating. Previously, a similar phase-change phenomenon has been observed in hydroxyapatite from dental enamel. Other Ca-bearing biominerals may therefore also be expected to be sensitive to electron irradiation.

  11. Otolith morphometrics distinguish difficult species of rockfishes in the Gulf of Alaska

    Directory of Open Access Journals (Sweden)

    Jeremy P Harris

    2015-12-01

    Full Text Available The oceans around Alaska are home to at least 40 species of rockfishes (Sebastidae. A number of these species are commercially important and are subject to strict catch limitations. However, regulators are hindered by the fact that some species are difficult to distinguish based on external characteristics and can only be conclusively identified using genetics. The rougheye (S. aleutianus and blackspotted (S. melanostictus rockfishes are one such example. Survey evidence suggests that these species segregate by depth, and that the shallower blackspotted is more prevalent in the fishery, raising concern that managing the species as a mixed stock might mask detrimental effects to the blackspotted population. This study examines otolith shape and morphometric analysis as tools for distinguishing these closely related species. Seven hundred and thirty-eight rockfish specimens were collected, their identity verified via genetic analysis, and their ages read. We then analyzed the data using several procedures including simple morphometrics and non-dimensional shape indices. We found that simple logistic regression across eight parameters was sufficient to correctly identify the species for more than 90% of the specimens. The use of shape indices did not improve prediction accuracy, but did eliminate allometric correlations among the predictor variables, which may be useful in some cases. A crucial aspect of the analysis is the inclusion of interactions with age in the model, which improved discrimination success. This may suggest an unrecognized difference in the growth rates of these species. Overall, we are capable of predicting species identity with fewer than 5% errors, which is sufficient to allow for separate management plans for the species. As such, we recommend that otolith stock discrimination techniques like these could provide an easy and effective way to discriminate many difficult-to-identify stocks, and further recommend that age data

  12. Complex life histories of fishes revealed through natural information storage devices: case studies of diadromous events as recorded by otoliths

    Science.gov (United States)

    Elfman, M.; Limburg, K. E.; Kristiansson, P.; Svedäng, H.; Westin, L.; Wickström, H.; Malmqvist, K.; Pallon, J.

    2000-03-01

    Diadromous fishes - species that move across salinity gradients as part of their life repertoire - form a major part of coastal and inland fisheries. Conventional mark-recapture techniques have long been used to track their movements, but give incomplete information at best. On the other hand, otoliths (ear-stones) of fishes can provide a complete record of major life history events, as reflected both in their microstructure and elemental composition. Strontium, which substitutes for calcium in the aragonite matrix of otoliths, is a powerful tracer of salinity histories in many migratory fishes. We measured Sr and Ca with a nuclear microprobe (PIXE) and show examples (eel, Anguilla anguilla; brown trout, Salmo trutta; American shad, Alosa sapidissima) of how the technique has solved several mysteries within fisheries biology.

  13. Slave to the rhythm: seasonal signals in otolith microchemistry reveal age of eastern Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Hüssy, Karin; Gröger, J.; Heidemann, F.;

    2016-01-01

    Annual growth zones in cod otoliths from the eastern Baltic stock are less discrete than in other cod stocks leading to biased age reading, which recently led to a failure of age-based assessment in the eastern Baltic cod stock. In this study, we explored the applicability of minor and trace...... element patterns in cod otoliths for age determination. By first identifying elements of interest in a stock without ageing problems, western Baltic cod, we then tested their applicability on another stock without ageing problems, North Sea cod, and finally applied this knowledge to estimate age of......, the same patterns in Cu, Zn, Rb, Mg, and Mn signals occurred. All eastern Baltic cod with low visual contrast between growth zones exhibited clearly defined synchronous cycles in Cu, Zn, Rb and Pb. Using a combined finite differencing method and structural break models approach, the statistical...

  14. Complex life histories of fishes revealed through natural information storage devices: case studies of diadromous events as recorded by otoliths

    International Nuclear Information System (INIS)

    Diadromous fishes - species that move across salinity gradients as part of their life repertoire - form a major part of coastal and inland fisheries. Conventional mark-recapture techniques have long been used to track their movements, but give incomplete information at best. On the other hand, otoliths (ear-stones) of fishes can provide a complete record of major life history events, as reflected both in their microstructure and elemental composition. Strontium, which substitutes for calcium in the aragonite matrix of otoliths, is a powerful tracer of salinity histories in many migratory fishes. We measured Sr and Ca with a nuclear microprobe (PIXE) and show examples (eel, Anguilla anguilla; brown trout, Salmo trutta; American shad, Alosa sapidissima) of how the technique has solved several mysteries within fisheries biology

  15. Three-dimensional organization of otolith-ocular reflexes in rhesus monkeys. I. Linear acceleration responses during off-vertical axis rotation

    Science.gov (United States)

    Angelaki, D. E.; Hess, B. J.

    1996-01-01

    1. The dynamic properties of otolith-ocular reflexes elicited by sinusoidal linear acceleration along the three cardinal head axes were studied during off-vertical axis rotations in rhesus monkeys. As the head rotates in space at constant velocity about an off-vertical axis, otolith-ocular reflexes are elicited in response to the sinusoidally varying linear acceleration (gravity) components along the interaural, nasooccipital, or vertical head axis. Because the frequency of these sinusoidal stimuli is proportional to the velocity of rotation, rotation at low and moderately fast speeds allows the study of the mid-and low-frequency dynamics of these otolith-ocular reflexes. 2. Animals were rotated in complete darkness in the yaw, pitch, and roll planes at velocities ranging between 7.4 and 184 degrees/s. Accordingly, otolith-ocular reflexes (manifested as sinusoidal modulations in eye position and/or slow-phase eye velocity) were quantitatively studied for stimulus frequencies ranging between 0.02 and 0.51 Hz. During yaw and roll rotation, torsional, vertical, and horizontal slow-phase eye velocity was sinusoidally modulated as a function of head position. The amplitudes of these responses were symmetric for rotations in opposite directions. In contrast, mainly vertical slow-phase eye velocity was modulated during pitch rotation. This modulation was asymmetric for rotations in opposite direction. 3. Each of these response components in a given rotation plane could be associated with an otolith-ocular response vector whose sensitivity, temporal phase, and spatial orientation were estimated on the basis of the amplitude and phase of sinusoidal modulations during both directions of rotation. Based on this analysis, which was performed either for slow-phase eye velocity alone or for total eye excursion (including both slow and fast eye movements), two distinct response patterns were observed: 1) response vectors with pronounced dynamics and spatial/temporal properties

  16. Coprecipitation with calcium hydroxide for determination of iron in fish otoliths by collision cell ICP-MS.

    Science.gov (United States)

    Daniels, Stephanie L; Arslan, Zikri

    2007-05-01

    A method has been described for the determination of iron from fish otoliths containing high levels of calcium by collision cell technology (CCT) ICP-MS. Iron (Fe) in otolith solutions was quantitatively coprecipitated with small amounts of calcium hydroxide by adding 1.0 M sodium hydroxide solution. The performance of CCT-ICP-MS pressurized with He/H(2) cell gas was investigated on the elimination of Ca-based spectral interferences at m/z 54, 56 and 57. Molecular ion interferences at m/z 54 and 56 were reduced by 2 orders of magnitude. However, the interferences at m/z 57 increased by the same amount in the presence of Ca in solutions owing to the formation of (40)Ca(16) OH(+) through reactions with H(2) in collision cell, indicating that (57)Fe was not suitable for the determination of Fe from otoliths. Results for (56)Fe suffered significantly from interferences of Ca-based molecular ions when the Ca concentration in solution exceeded 100 microg ml(-1), for which matrix-matched calibration was required for accurate determination. CCT with the aid of He/H(2) cell gas proved to be very effective in eliminating the interferences ((40)Ar(14)N(+) and (40)Ca(14)N(+)) at m/z 54. Presence of Ca up to 300 microg ml(-1) had virtually no effect on the ion signals of (54)Fe, which with low background signals, afforded accurate determination of Fe from otoliths by using aqueous external standards. PMID:17294508

  17. Elemental patterns in red hind (Epinephelus guttatus) otoliths from Bermuda and Puerto Rico reflect growth rate, not temperature

    OpenAIRE

    Sadovy, Y; Severin, KP

    1994-01-01

    Sodium, sulfur, calcium, and strontium concentrations were measured (with an electron microprobe across sectioned wild red hind (Epinephelus guttatus) otoliths from Puerto Rico and Bermuda. A single inverse relationship between strontium/calcium (Sr/Ca) ratios and log body growth rate describes the data from both localities. Patterns in Sr/Ca ratios have been used to infer temperature histories of individual fish; our data indicate that there is not a single Sr/Ca-temperature relationship cap...

  18. Life history inhomogeneity in Baltic Sea whitefish populations revealed by otolith strontium signatures – identification of stocked fish

    Directory of Open Access Journals (Sweden)

    Henry Hägerstrand

    2015-11-01

    The strontium concentrations in the otolith cores of whitefish from River Tornionjoki were higher than that of the four otoliths with low core strontium from fishes caught at sea (Table 1. Supposing that this latter group represent stocked fish raised in freshwater ponds, the vast majority of River Tornionjoki whitefish is naturally reproduced fish. This is plausible because in River Tornionjoki, the major whitefish spawning river in Finland, no larger stocking have been made since 1990s (Jokikokko and Huhmarniemi 2014. In conclusion, the concentration of otolith core strontium differs in whitefish hatched in fresh-water and in whitefish hatched in river water or in brackish Baltic Sea water. This difference can be used to reveal stocked whitefish. Barium concentration may be an even better indicator in this respect than strontium, as previous results indicate (Hägerstrand et al., 2015. Stocked river spawning whitefish appear in large amount at the southern feeding grounds around the Åland Islands, as already indicated by e.g. Leskelä et al. (2009.

  19. Role of irregular otolith afferents in the steady-state nystagmus during off-vertical axis rotation

    Science.gov (United States)

    Angelaki, D. E.; Perachio, A. A.; Mustari, M. J.; Strunk, C. L.

    1992-01-01

    1. During constant velocity off-vertical axis rotations (OVAR) in the dark a compensatory ocular nystagmus is present throughout rotation despite the lack of a maintained signal from the semicircular canals. Lesion experiments and canal plugging have attributed the steady-state ocular nystagmus during OVAR to inputs from the otolith organs and have demonstrated that it depends on an intact velocity storage mechanism. 2. To test whether irregularly discharging otolith afferents play a crucial role in the generation of the steady-state eye nystagmus during OVAR, we have used anodal (inhibitory) currents bilaterally to selectively and reversibly block irregular vestibular afferent discharge. During delivery of DC anodal currents (100 microA) bilaterally to both ears, the slow phase eye velocity of the steady-state nystagmus during OVAR was reduced or completely abolished. The disruption of the steady-state nystagmus was transient and lasted only during the period of galvanic stimulation. 3. To distinguish a possible effect of ablation of the background discharge rates of irregular vestibular afferents on the velocity storage mechanism from specific contributions of the dynamic responses from irregular otolith afferents to the circuit responsible for the generation of the steady-state nystagmus, bilateral DC anodal galvanic stimulation was applied during optokinetic nystagmus (OKN) and optokinetic afternystagmus (OKAN). No change in OKN and OKAN was observed.(ABSTRACT TRUNCATED AT 250 WORDS).

  20. Age Determination of Microlepidotus brevipinnis (Steindachner, 1869 (Pisces: Haemulidae in the Coast of Jalisco, Mexico, by Reading Otoliths and Scales

    Directory of Open Access Journals (Sweden)

    E.G. Cabral-Solis

    2010-01-01

    Full Text Available This study deals with age determination of the brassy grunt Microlepidotus brevipinnis by reading otoliths (sagittae and scales which allowed the identification of 13 age groups. Growth of otoliths and scales is proportional to the growth of the fish. The time of formation of fast and slow growth bands in sagittae, as well as the time of ring formation in the scales is one year. The highest growth in length of this species takes place during the first year of life, in which the organism reaches 125.0 mm, this reduces natural mortality of the individuals by decreasing depredation. Growth in weight of this species is isometric. Sexual differentiation of the organisms is apparent after the age of two years and there were differences in the average length for each age in scales and otoliths for males and females. The age of other members of the Haemulidae family were compared with those obtained in the present study and M. brevipinnis reaches its oldest age in 13 years. It occupies a middle point (442.4 mm in relation to the total lengths of other haemulids in the Mexican Pacific coast.

  1. Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques: lead-radium and bomb radiocarbon dating.

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, A H; Kerr, L A; Cailliet, G M; Brown, T A; Lundstrom, C C; Stanley, R D

    2007-11-04

    Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from southeast Alaska to southern California, but localized stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from about 20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and lifespan estimates remain largely unvalidated. Typical age validation techniques have limited application for canary rockfish because they are deep dwelling and may be long lived. In this study, the unaged otolith of the pair from fish aged at the Department of Fisheries and Oceans Canada was used in one of two age validation techniques: (1) lead-radium dating and (2) bomb radiocarbon ({sup 14}C) dating. Age estimate accuracy and the validity of age estimation procedures were validated based on the results from each technique. Lead-radium dating proved successful in determining a minimum estimate of lifespan was 53 years and provided support for age estimation procedures up to about 50-60 years. These findings were further supported by {Delta}{sup 14}C data, which indicated a minimum estimate of lifespan was 44 {+-} 3 years. Both techniques validate, to differing degrees, age estimation procedures and provide support for inferring that canary rockfish can live more than 80 years.

  2. Electronmicroscopic Investigations on the Role of Vesicle-like Bodies in Inner Ear Maculae for Fish Otolith Growth

    Science.gov (United States)

    Ibsch, M.; Vöhringer, P.; Anken, R. H.; Rahmann, H.

    The presence, morphology and possible origin of vesicle-like bodies (VBs) within the inner ear otolithic membrane of developmental stages of cichlid fish Oreochromis mossambicus and adult swordtail fish Xiphophorus helleri was analysed by means of transmission and scanning electron microscopy (TEM and SEM, respectively) employing various fixation procedures. The VBs are believed to be involved in the formation of the otolith (or statolith in birds and mammals) regarding the supply of the otolith's organic material. Increasing the osmolarity of the fixation medium decreased the number of VBs seen. Decalcification ended up in a complete disappearance of the VBs. Whilst a fixation with glutaraldehyde followed by OS04 fixation yielded numerous VBs, only few of them were observed when the tissue was fixed with glutaraldehyde and OSO4 simultaneously. Therefore, the results strongly suggest that the VBs are fixative (i.e., glutaraldehyde) induced artifacts, so-called blisters. With this, the supply of an oto- or statolith's organic material remains obscure. Possibly, it is provided by secretion from the supporting cells as has been hypothesized earlier

  3. Growth conditions of 0-group plaice Pleuronectes platessa in the western Wadden Sea as revealed by otolith microstructure analysis

    Science.gov (United States)

    Cardoso, Joana F. M. F.; Freitas, Vânia; de Paoli, Hélène; Witte, Johannes IJ.; van der Veer, Henk W.

    2016-05-01

    Growth studies based on population-based growth estimates are limited by the fact that they do not take into account differences in age/size structure within the population. To overcome these problems, otolith microstructure analysis is often used to estimate individual growth. Here, we analyse growth of 0-group plaice in the western Wadden Sea in two years: a year preceded by a mild winter (1995) and a year preceded by a severe winter (1996). Growth was analysed by combining information on individual growth based on otolith analysis with predictions of maximum growth (= under optimal food conditions) based on a Dynamic Energy Budget model. Otolith analysis revealed that settlement occurred earlier in 1995 than in 1996. In both years, one main cohort was found, followed by a group of late settlers. No differences in mean length-at-age were found between these groups. DEB modelling suggested that growth was not maximal during the whole growing season: realized growth (the fraction of maximum growth realized by 0-group plaice) declined in the summer, although this decline was relatively small. In addition, late settling individuals exhibited lower realized growth than individuals from the main cohort. This study confirms that growth conditions for 0-group plaice are not optimal and that a growth reduction occurs in summer, as suggested in previous studies.

  4. Estimating contemporary early life-history dispersal in an estuarine fish: integrating molecular and otolith elemental approaches.

    Science.gov (United States)

    Bradbury, I R; Campana, S E; Bentzen, P

    2008-03-01

    Dispersal during the early life history of the anadromous rainbow smelt, Osmerus mordax, was examined using assignment testing and mixture analysis of multilocus genotypes and otolith elemental composition. Six spawning areas and associated estuarine nurseries were sampled throughout southeastern Newfoundland. Samples of adults and juveniles isolated by > 25 km displayed moderate genetic differentiation (F(ST) ~ 0.05), whereas nearby ( 80% self-assignment) with nearby runs self-assigning at rates between 50 % and 70%. Assignment and mixture analysis of juveniles using adult baselines indicated high local recruitment at several locations (70-90%). Nearby (< 25 km) estuaries at the head of St Mary's Bay showed mixtures of individuals (i.e. 20-40% assignment to adjacent spawning location). Laser ablation inductively coupled mass spectrometry transects across otoliths of spawning adults of unknown dispersal history were used to estimate dispersal among estuaries across the first year of life. Single-element trends and multivariate discriminant function analysis (Sr:Ca and Ba:Ca) classified the majority of samples as estuarine suggesting limited movement between estuaries (< 0.5%). The mixtures of juveniles evident in the genetic data at nearby sites and a lack of evidence of straying in the otolith data support a hypothesis of selective mortality of immigrants. If indeed selective mortality of immigrants reduces the survivorship of dispersers, estimates of dispersal in marine environments that neglect survival may significantly overestimate gene flow. PMID:18321254

  5. Interannual variations in the hatching pattern, larval growth and otolith size of a sand-dwelling fish from central Chile

    Science.gov (United States)

    Rodríguez-Valentino, Camilo; Landaeta, Mauricio F.; Castillo-Hidalgo, Gissella; Bustos, Claudia A.; Plaza, Guido; Ojeda, F. Patricio

    2015-09-01

    The interannual variation (2010-2013) of larval abundance, growth and hatching patterns of the Chilean sand stargazer Sindoscopus australis (Pisces: Dactyloscopidae) was investigated through otolith microstructure analysis from samples collected nearshore (<500 m from shore) during austral late winter-early spring off El Quisco bay, central Chile. In the studied period, the abundance of larval stages in the plankton samples varied from 2.2 to 259.3 ind. 1000 m-3; larval abundance was similar between 2010 and 2011, and between 2012 and 2013, but increased significantly from 2011 to 2012. The estimated growth rates increased twice, from 0.09 to 0.21 mm day-1, between 2011 and 2013. Additionally, otolith size (radius, perimeter and area), related to body length of larvae, significantly decreased from 2010 to 2012, but increases significantly in 2013. Although the mean values of microincrement widths of sagitta otoliths were similar between 2010 and 2011 (around 0.6-0.7 μm), the interindividual variability increases in 2011 and 2013, suggesting large environmental variability experienced by larvae during these years. Finally, the hatching pattern of S. australis changed significantly from semi-lunar to lunar cycle after 2012.

  6. Otolith chemistry of fishes from Kosi Bay, South Africa: A preliminary multiple analytical methods approach to reconstruct fish migrations

    Science.gov (United States)

    Holbach, Andreas; Cowley, Paul D.; Kramar, Utz; Neumann, Thomas

    2012-08-01

    Over exploitation of fish stocks in coastal areas is a subject of global concern. Increasing numbers of traditional fish traps, recreational fishing effort and unknown extents of illegal gillnetting are blamed for the declining abundance of estuarine-dependent fish species in the Kosi Bay estuarine lake system in KwaZulu-Natal, South Africa. Otoliths from four important fishery species (Lutjanus argentimaculatus, Pomadasys commersonnii, Acanthopagrus vagus, and Rhabdosargus sarba) and water samples collected from throughout the Kosi Bay system were analyzed for trace element constituents and δ18O values, in an attempt to reconstruct fish movements. The applied microscopic X-ray fluorescence analysis proved valuable in detecting μm-scale spatially resolved Sr/Ca ratio distributions across otolith thin sections. Sr/Ca ratios and δ18O in otoliths correlated well with ambient water conditions and, thus, enabled us to reconstruct migratory histories of individual fish in the estuarine lake system. The findings are representative of the known biology of these species, although exact spatial and temporal ranges of migrations remain unclear. Interestingly, samples of two species (L. argentimaculatus and R. sarba) did not show any clue of migrations back to sea, which would be necessary for successful spawning. Further laboratory and field investigations with larger sample sizes are necessary to detect fishery impacts on migratory behavior at a population level.

  7. Parameterization of a multiagent system for roof edge detection: an application to growth ring detection on fish otoliths

    Science.gov (United States)

    Guillaud, Anne; Benzinou, Abdessalam; Troadec, Herve; Rodin, Vincent; Le Bihan, Jean

    2000-03-01

    In this paper we present a method of segmentation using a multiagent system, and an application to fish otolith growth ring detection. The otoliths images are composed of alternative concentric dark and light rings, the number of which increases with the age of the fish. Up to now, the identification of growth rings, for age estimation, is routinely achieved by human readers, but this task is tedious and depends on the reader's subjectivity. The system proposed here is composed of several agents whose individual task is to detect local extremes on a grayscale image. For this aim the agents are provided with sensors on the gray levels of the image. By computing the mean gray level of two sensors placed in front of it, the agent, if it searches for light rings (respectively dark) will decide to turn in the direction of the lighter (respectively darker) sensor. The path of the agents has been tested as a roof edge detector, using the Canny criteria: good detection, good localization, and low multiple response, in order to choose the best parameters ruling the agents behavior, according to the image structures. Tests have been first achieved on synthetic images, and then on otoliths images.

  8. Influence of DNA isolation from historical otoliths on nuclear-mitochondrial marker amplification and age determination in an overexploited fish, the common sole (Solea solea L.).

    Science.gov (United States)

    Cuveliers, E L; Bolle, L J; Volckaert, F A M; Maes, G E

    2009-05-01

    Historical otolith collections are crucial in assessing the evolutionary consequences of natural and anthropogenic changes on the demography and connectivity of commercially important fish species. Hence, it is important to define optimal protocols for purifying DNA from such valuable information sources while avoiding any damage to the physical structure of the otolith. Before being able to conclude on the harmlessness of a method, it is important to validate protocols on different kinds of otoliths by testing purification methodologies under standardized conditions. Here we compare the effect of two DNA extraction methods on the success in identifying the age in an overexploited marine fish, the common sole (Solea solea L.). To ensure optimal future population genetic and demographic analyses, we assessed DNA quantity and tested the DNA quality by investigating the amplification success of a mitochondrial and nuclear marker. Our results show that the choice of the DNA extraction method had a significant effect on the success of using these otoliths in age and growth analyses. Standard commercial and published protocols resulted in a severe damaging of the otolith structure, hampering accurate preparation and analyses of the morphological structures of the otoliths. Shortening the lysis time and lowering the EDTA (ethylene diamine tetraacetic acid) and SDS (sodium dodecylsulphate) concentration turned out to be beneficial for the stability of otolith structure, while maintaining an overall high DNA quality measured through polymerase chain reaction amplification success. We therefore recommend that care should be taken when choosing the extraction method for a molecular study on archived samples, in order to enable the maximal use of information embedded in historical material. PMID:21564731

  9. Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS).

    Science.gov (United States)

    Kenduzler, Erdal; Ates, Mehmet; Arslan, Zikri; McHenry, Melanie; Tchounwou, Paul B

    2012-05-15

    A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH(4)) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH(3)Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg(0)) with 1 × 10(-4)% (m/v) NaBH(4). CH(3)Hg(I) required a minimum of 0.5% (m/v) NaBH(4) for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH(3)Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg L(-1) Hg(II) solution. The detection limits were 4.2 and 6.4 ng L(-1) (ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO(3) (99.99%) spiked with Hg(II) and CH(3)HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100°C. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH(3)Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg g(-1) for the red emperor and 0.021 ± 0.003 μg g(-1) for the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was

  10. Age estimation of juvenile European hake Merluccius merluccius based on otolith microstructure analysis: a slow or fast growth pattern?

    Science.gov (United States)

    Pattoura, P; Lefkaditou, E; Megalofonou, P

    2015-03-01

    The main goal of this study was to examine otolith microstructure and to estimate the age and growth of European hake Merluccius merluccius from the eastern Mediterranean Sea. One hundred and twenty-nine specimens ranging from 102 to 438 mm in total length (LT ) were used. Age estimations were based on the study of the otolith microstructure, which was revealed after grinding both frontal sides of otoliths. The enumerations of the daily growth increments (DGI) as well as their width (WDGI ) measurements were made on calibrated digital images. The number of DGI in otoliths ranged between 163 and 717. Four phases in the WDGI evolution were distinguished: (1) larval-juvenile pelagic phase, with an increasing trend in WDGI up to the 60th DGI, (2) settlement phase, with a short-term deceleration in WDGI between the 61st and 150th DGI, (3) juvenile demersal phase, characterized by a stabilization of WDGI from 151st to 400th DGI and (4) adult phase, with a decreasing trend in WDGI after the 400th DGI. Age, sex and month of formation were found to affect the WDGI in all phases, with the exception of age at the juvenile demersal phase. The power curve with intercept model described best the relationship of M. merluccius LT with age (TDGI ), according to Akaike criteria, revealing differences in growth between females [LT = 65 · 36(TDGI )(0 · 40) - 388 · 55] and males [LT = 69 · 32(TDGI )(0 · 37) - 352 · 88] for the sizes examined. The mean daily growth rates were 0·61 mm day(-1) for females and 0·52 mm day(-1) for males, resulting in an LT of 283 and 265 mm at the end of their first year of life. In comparison with previous studies on the Mediterranean Sea, the results of this study showed a greater growth rate, similar to results from tagging experiments and otolith microstructure analyses for M. merluccius in other geographic areas. PMID:25545134

  11. Spatio-temporal and interspecific variation in otolith trace-elemental fingerprints in a temperate estuarine fish assemblage

    Science.gov (United States)

    Swearer, Stephen E.; Forrester, Graham E.; Steele, Mark A.; Brooks, Andrew J.; Lea, David W.

    2003-04-01

    We tested whether estuarine fishes have site-specific differences in the concentrations of trace elements in their otoliths that can be used as 'fingerprints' to identify them to their estuary of origin. To evaluate the robustness of this approach, we tested whether elemental fingerprints were consistent among individuals of five species that were collected in 1996 from three temperate estuaries in southern California. We also tested whether elemental fingerprints were consistent between spring and autumn 1996 for three species in one of the sites, Carpinteria Marsh. The species evaluated comprised a mid-water-dwelling smelt ( Atherinops affinis), two benthic gobies ( Clevelandia ios and Ilypnus gilberti), and two flatfish ( Paralichthys californicus and Hypsopsetta guttulata). The concentrations of six elements (Mn, Cu, Zn, Sr, Ba, and Pb) were determined in the otoliths using inductively coupled plasma-mass spectrometry (ICP-MS). Within estuaries, the five species exhibited strong variation in elemental concentration, indicating substantial interspecific differences in otolith environmental history. When the five fish species were considered separately, multivariate (MANOVA) and univariate (ANOVA) analyses of variance indicated that the elemental composition of otoliths differed significantly among the estuaries in four of the five species. Based on linear discriminant function analyses (DFA), differences were strong enough that trace element composition could be used to accurately assign fish to their site of origin [mean (range): 93.5% (74-100%)]. However, elemental signatures within Carpinteria Marsh were not consistent between spring and autumn 1996, and this was reflected in a substantial reduction in the accuracy of assigning fish to their true site of origin. When we compared site differences between fish species (site×species interactions), the elemental fingerprints were most similar between closely related species (e.g. the two gobies and the two

  12. Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS)†

    Science.gov (United States)

    Kenduzler, Erdal; Ates, Mehmet; Arslan, Zikri; McHenry, Melanie; Tchounwou, Paul B.

    2012-01-01

    A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH4) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH3Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg0) with 1×10−4% (m/v) NaBH4. CH3Hg(I) required a minimum of 0.5% (m/v) NaBH4 for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH3Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg L−1 Hg(II) solution. The detection limits were 4.2 and 6.4 ng L−1 (ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO3 (99.99%) spiked with Hg(II) and CH3HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100 oC. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH3Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg g−1 for the red emperor and 0.021 ± 0.003 μg g−1 for the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was very low suggesting a

  13. Species and life-history affects the utility of otolith chemical composition to determine natal stream-of-origin in Pacific salmon

    Science.gov (United States)

    Zimmerman, Christian E.; Swanson, Heidi K.; Volk, Eric C.; Kent, Adam J.R.

    2013-01-01

    To test the utility of otolith chemical composition as a tool for determining the natal stream of origin for salmon, we examined water chemistry and otoliths of juvenile and adult Chum Salmon Oncorhynchus keta and Coho Salmon O. kisutch from three watersheds (five rivers) in the Norton Sound region of Alaska. The two species are characterized by different life histories: Coho Salmon rear in freshwater for up to 3 years, whereas Chum Salmon emigrate from freshwater shortly after emergence. We used laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) to quantify element: Ca ratios for Mg, Mn, Zn, Sr, and Ba, and we used multicollector LA-ICP-MS to determine 87Sr:86Sr ratios in otolith regions corresponding to the period of freshwater residence. Significant differences existed in both water and otolith elemental composition, suggesting that otolith composition could be used to discriminate the natal origin of Coho Salmon and Chum Salmon but only when 87Sr:86Sr ratios were included in the discriminant function analyses. The best discriminant model included 87Sr:86Sr ratios, and without 87Sr:86Sr ratios it was difficult to discriminate among watersheds and rivers. Classification accuracy was 80% for Coho Salmon and 68% for Chum Salmon, indicating that this method does not provide sufficient sensitivity to estimate straying rates of Pacific salmon at the scale we studied.

  14. Distinguishing wild vs. stocked lake trout (Salvelinus namaycush) in Lake Ontario: Evidence from carbon and oxygen stable isotope values of otoliths

    Science.gov (United States)

    Schaner, T.; Patterson, W.P.; Lantry, B.F.; O'Gorman, R.

    2007-01-01

    We investigated the potential for using carbon and oxygen isotope values of otolith carbonate as a method to distinguish naturally produced (wild) lake trout (Salvelinus namaycush) from hatchery-reared lake trout in Lake Ontario. We determined δ 13C(CaCO3) and δ 18O(CaCO3) values of otoliths from juvenile fish taken from two hatcheries, and of otoliths from wild yearlings. Clear differences in isotope values were observed between the three groups. Subsequently we examined otoliths from large marked and unmarked fish captured in the lake, determining isotope values for regions of the otolith corresponding to the first year of life. Marked (i.e., stocked) fish showed isotope ratios similar to one of the hatchery groups, whereas unmarked fish, (wild fish or stocked fish that lost the mark) showed isotope ratios similar either to one of the hatchery groups or to the wild group. We interpret these data to suggest that carbon and oxygen isotope values can be used to determine the origin of lake trout in Lake Ontario, if a catalogue of characteristic isotope values from all candidate years and hatcheries is compiled.

  15. Atlas of marine bony fish otoliths (Sagittae of Southeastern - Southern Brazil Part I: Gadiformes (Macrouridae, Moridae, Bregmacerotidae, Phycidae and Merlucciidae; Part II: Perciformes (Carangidae, Sciaenidae, Scombridae and Serranidae

    Directory of Open Access Journals (Sweden)

    Carmen Lucia Del Bianco Rossi-Wongtschowski

    2014-01-01

    Full Text Available The drawings, detailed pictures, precise descriptions and measurements that characterize otoliths must be made available for studies in various areas, including taxonomy, phylogeny, ecology, fisheries, paleontology, diversity, predator-prey relationships and modeling. The Collection of Teleostei Fish Otoliths of Southeastern-Southern Brazil (COSS-Brasil of IOUSP contains 45,000 pairs of otoliths from 210 species. This publication is the first in a series that will constitute an atlas of Teleostei otoliths for southeastern-southern Brazil and presents the results of the morphologic and morphometric analyses of 11 Gadiformes and 36 Perciformes species by means of the most commonly used features, measurements and indices. Three otoliths of each species were illustrated and photographed whenever possible. The frequency of occurrence was calculated for each characteristic by total length classes (TL, and the ontogenetic differences were analyzed (multiple χ2 test; significance 0.05. Morphometric analyses were conducted for each characteristic per total length (TL class and for the whole sample, and the ontogenetic differences were analyzed.

  16. Three-dimensional organization of otolith-ocular reflexes in rhesus monkeys. III. Responses To translation

    Science.gov (United States)

    Angelaki, D. E.

    1998-01-01

    The three-dimensional (3-D) properties of the translational vestibulo-ocular reflexes (translational VORs) during lateral and fore-aft oscillations in complete darkness were studied in rhesus monkeys at frequencies between 0.16 and 25 Hz. In addition, constant velocity off-vertical axis rotations extended the frequency range to 0.02 Hz. During lateral motion, horizontal responses were in phase with linear velocity in the frequency range of 2-10 Hz. At both lower and higher frequencies, phase lags were introduced. Torsional response phase changed more than 180 degrees in the tested frequency range such that torsional eye movements, which could be regarded as compensatory to "an apparent roll tilt" at the lowest frequencies, became anticompensatory at all frequencies above approximately 1 Hz. These results suggest two functionally different frequency bandwidths for the translational VORs. In the low-frequency spectrum (frequency independent. At higher frequencies however, both horizontal and torsional response sensitivity and phase exhibit a similar frequency dependence, suggesting a common role during head translation. During up-down motion, vertical responses were in phase with translational velocity at 3-5 Hz but phase leads progressively increased for lower frequencies (>90 degrees at frequencies frequency response characteristics of the translational VORs were fitted by "periphery/brain stem" functions that related the linear acceleration input, transduced by primary otolith afferents, to the velocity signals providing the input to the velocity-to-position neural integrator and the oculomotor plant. The lowest-order, best-fit periphery/brain stem model that approximated the frequency dependence of the data consisted of a second order transfer function with two alternating poles (at 0.4 and 7.2 Hz) and zeros (at 0.035 and 3.4 Hz). In addition to clearly differentiator dynamics at low frequencies (less than approximately 0.5 Hz), there was no frequency bandwidth

  17. Oldest isotopically characterized fish otoliths provide insight to Jurassic continental climate of Europe

    Science.gov (United States)

    Patterson, William P.

    1999-03-01

    Large, shallow, epeiric seas and adjacent lagoons such as those described herein likely played a significant role in moderating Jurassic coastal and continental climate. Jurassic (Bathonian) ocean surface temperatures in Scotland have been calculated from δ18O(CaCO3) values of a suite of the oldest well-preserved fish otoliths analyzed to date. Otolith δ18O values range from -4.7‰ to -1.9‰ (Vienna Peedee belemnite, VPDB), while δ13C(CaCO3) values vary from -5.4‰ to +1.5‰ (VPDB), representing the oldest stable isotopic record of paleodiet, paleoecology, and fish migration to date. Using a global ocean δ18O(H2O) value of -1.0‰ (Vienna standard mean ocean water, VSMOW) for an ice-free Jurassic, fish species that migrated from estuarine to open marine water record time-averaged temperatures of 23 °C. Estuarine fish, assuming a similar temperature, record variation in δ18O(H2O) values from -3.7‰ to -2.0‰ (VSMOW). That significant mixing of fresh water and seawater occurred in the Jurassic in Scotland is in general agreement with data presented by others (molluscan fauna, lithostratigraphy, paleogeography, and paleocirculation models). The δ18O values and temperatures derived in this study correspond to the meteorologic and hydrologic parameters of a mid-latitude maritime climate with low seasonality, a mean temperature of 23 °C, and abundant precipitation and humidity. The δ18O(H2O) values calculated from estuarine fish indicate that rainfall must have a δ18O(H2O) value lower than -3.7‰ (VSMOW). Values of δ18O and δ13C suggest an environment hydrologically similar to that observed in the Everglades of south Florida or the estuaries of south Texas, both notable fish nurseries today. However, sea-surface temperatures were lower than those of modern Florida or Texas as evidenced by reduced evaporative enrichment of δ18O(H2O) values.

  18. Ion microprobe measurement of strontium isotopes in calcium carbonate with application to salmon otoliths

    Science.gov (United States)

    Weber, P.K.; Bacon, C.R.; Hutcheon, I.D.; Ingram, B.L.; Wooden, J.L.

    2005-01-01

    The ion microprobe has the capability to generate high resolution, high precision isotopic measurements, but analysis of the isotopic composition of strontium, as measured by the 87Sr/ 86Sr ratio, has been hindered by isobaric interferences. Here we report the first high precision measurements of 87Sr/ 86Sr by ion microprobe in calcium carbonate samples with moderate Sr concentrations. We use the high mass resolving power (7000 to 9000 M.R.P.) of the SHRIMP-RG ion microprobe in combination with its high transmission to reduce the number of interfering species while maintaining sufficiently high count rates for precise isotopic measurements. The isobaric interferences are characterized by peak modeling and repeated analyses of standards. We demonstrate that by sample-standard bracketing, 87Sr/86Sr ratios can be measured in inorganic and biogenic carbonates with Sr concentrations between 400 and 1500 ppm with ???2??? external precision (2??) for a single analysis, and subpermil external precision with repeated analyses. Explicit correction for isobaric interferences (peak-stripping) is found to be less accurate and precise than sample-standard bracketing. Spatial resolution is ???25 ??m laterally and 2 ??m deep for a single analysis, consuming on the order of 2 ng of material. The method is tested on otoliths from salmon to demonstrate its accuracy and utility. In these growth-banded aragonitic structures, one-week temporal resolution can be achieved. The analytical method should be applicable to other calcium carbonate samples with similar Sr concentrations. Copyright ?? 2005 Elsevier Ltd.

  19. On Strongly Coupled Linear Elliptic Systems with Application to Otolith Membrane Distortion

    Directory of Open Access Journals (Sweden)

    I. K. Youssef

    2008-01-01

    Full Text Available Problem Statement: In this research, the author discussed the problems associated with the approximation of the mixed derivative terms appearing in strongly coupled linear elliptic systems by the finite difference method over irregular domains. To avoid the appearance of mixed derivative terms the author introduced a reformulation for the system through introducing a new dependent variable which adds one supplementary (simple differential equation to the system but does not change its elliptic character. Approach: The basic idea in the reformulation is the direct generation of the Laplacian operator which has an efficient finite difference treatment. Results: Two finite difference formulae with symmetric appearance approximating the first order derivatives on curved boundaries up to O(h2 are established, that can be considered as a generalization to the well known central formula. Applications to the otolith membrane model have proved the reliability and efficiency of the present treatment in comparison with other methods. Conclusions/Recommendations: Although, this treatment has increased the number of algebraic equations approximating the system linearly 3n instead of 2n, the overall accuracy is increased quadratically. The band width of matrix of coefficients of the algebraic system is decreased and there is no need to interpolate along the diagonals due to the absence of mixed derivatives. The treatment is promising and other extensions are mentioned.

  20. Hair cell regeneration in the bullfrog vestibular otolith organs following aminoglycoside toxicity

    Science.gov (United States)

    Baird, Richard A.; Torres, M. A.; Schuff, N. R.

    1994-01-01

    Adult bullfrogs were given single intraotic injections of the aminoglycoside antibiotic gentamicin sulfate and sacrificed at postinjection times ranging from 0.5 to 9 days. The saccular and utricular maculae of normal and injected animals were examined in wholemount and cross-section. Intraotic 200 (mu) M gentamicin concentrations resulted in the uniform destruction of the hair bundles and, at later times, the cell bodies of saccular hair cells. In the utriculus, striolar hair cells were selectively damaged while extrastriolar hair cells were relatively unaffected. Regenerating hair cells, identified in sectioned material by their small cell bodies and short, well-formed hair bundles, were seen in the saccular and utricular maculae as early as 24-48 h postinjection. Immature versions of mature hair cell types in both otolith organs were recognized by the presence of absence of a bulbed kinocilia and the relative lengths of their kinocilia and longest sterocilia. Utricular hair cell types with kinocilia longer than their longest stereocilia were observed at earlier times than hair cell types with shorter kinocilia. In the same sacculus, the hair bundles of gentamicin-treated animals, even at 9 days postinjection, were significantly smaller than those of normal animals. The hair bundles of utricular hair cells, on the other hand, reached full maturity within the same time period.

  1. Convergence of limb, visceral, and vertical semicircular canal or otolith inputs onto vestibular nucleus neurons

    Science.gov (United States)

    Jian, B. J.; Shintani, T.; Emanuel, B. A.; Yates, B. J.

    2002-01-01

    The major goal of this study was to determine the patterns of convergence of non-labyrinthine inputs from the limbs and viscera onto vestibular nucleus neurons receiving signals from vertical semicircular canals or otolith organs. A secondary aim was to ascertain whether the effects of non-labyrinthine inputs on the activity of vestibular nucleus neurons is affected by bilateral peripheral vestibular lesions. The majority (72%) of vestibular nucleus neurons in labyrinth-intact animals whose firing was modulated by vertical rotations responded to electrical stimulation of limb and/or visceral nerves. The activity of even more vestibular nucleus neurons (93%) was affected by limb or visceral nerve stimulation in chronically labyrinthectomized preparations. Some neurons received non-labyrinthine inputs from a variety of peripheral sources, including antagonist muscles acting at the same joint, whereas others received inputs from more limited sources. There was no apparent relationship between the spatial and dynamic properties of a neuron's responses to tilts in vertical planes and the non-labyrinthine inputs that it received. These data suggest that non-labyrinthine inputs elicited during movement will modulate the processing of information by the central vestibular system, and may contribute to the recovery of spontaneous activity of vestibular nucleus neurons following peripheral vestibular lesions. Furthermore, some vestibular nucleus neurons with non-labyrinthine inputs may be activated only during particular behaviors that elicit a specific combination of limb and visceral inputs.

  2. Preliminary results of Sr:Ca ratios of Coilia nasus in otoliths by micro-PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, L. [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China); Guo, H. [Institute of Life Science, Shanghai Fisheries University, Shanghai 200090 (China); Shen, H. [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China)]. E-mail: haoshen@fudan.edu.cn; Li, X. [Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201800 (China); Tang, W. [Institute of Life Science, Shanghai Fisheries University, Shanghai 200090 (China); Liu, J. [Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201800 (China); Jin, J. [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China); Mi, Y. [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China)

    2007-07-15

    Coilia nasus, distributed in Changjiang River as well as northwest Pacific, has a high economic value owing to its delicacy and nutritional value. Recently, the fishing yields in Changjiang River have decreased dramatically due to excessive fishing and changes in the aquatic ecology. In order to prevent excessive fishing effectively, the life history pattern of C. nasus should be known in detail. Ootoliths contain much information about a fish's life history, because elemental concentrations remain unaltered after deposition, and can be analysed. C. nasus collected from Jing Jiang (lower reaches of the Changjiang River) and Jiu Duan Sha (the estuary of the Changjiang River) were studied by measuring Sr:Ca ratios in their otoliths using micro-PIXE. On average, the Sr:Ca ratios of estuarine C. nasus were found to be higher. The Sr:Ca ratios were higher in the core regions and lower in the outermost marginal regions, and shows fluctuations in certain regions. Possible corresponding life history patterns are discussed.

  3. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization.

    Science.gov (United States)

    Ren, Dongni; Li, Zhuo; Gao, Yonghua; Feng, Qingling

    2010-10-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH2 and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH2 and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different. PMID:20844320

  4. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization

    Energy Technology Data Exchange (ETDEWEB)

    Ren Dongni; Li Zhuo; Gao Yonghua; Feng Qingling, E-mail: biomater@mail.tsinghua.edu.c [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2010-10-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH{sub 2} and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH{sub 2} and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  5. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization

    International Nuclear Information System (INIS)

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH2 and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH2 and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  6. Preliminary results of Sr:Ca ratios of Coilia nasus in otoliths by micro-PIXE

    International Nuclear Information System (INIS)

    Coilia nasus, distributed in Changjiang River as well as northwest Pacific, has a high economic value owing to its delicacy and nutritional value. Recently, the fishing yields in Changjiang River have decreased dramatically due to excessive fishing and changes in the aquatic ecology. In order to prevent excessive fishing effectively, the life history pattern of C. nasus should be known in detail. Ootoliths contain much information about a fish's life history, because elemental concentrations remain unaltered after deposition, and can be analysed. C. nasus collected from Jing Jiang (lower reaches of the Changjiang River) and Jiu Duan Sha (the estuary of the Changjiang River) were studied by measuring Sr:Ca ratios in their otoliths using micro-PIXE. On average, the Sr:Ca ratios of estuarine C. nasus were found to be higher. The Sr:Ca ratios were higher in the core regions and lower in the outermost marginal regions, and shows fluctuations in certain regions. Possible corresponding life history patterns are discussed

  7. In search of the dead zone: Use of otoliths for tracking fish exposure to hypoxia

    Science.gov (United States)

    Limburg, Karin E.; Walther, Benjamin D.; Lu, Zunli; Jackman, George; Mohan, John; Walther, Yvonne; Nissling, Anders; Weber, Peter K.; Schmitt, Axel K.

    2015-01-01

    Otolith chemistry is often useful for tracking provenance of fishes, as well as examining migration histories. Whereas elements such as strontium and barium correlate well with salinity and temperature, experiments that examine manganese uptake as a function of these parameters have found no such correlation. Instead, dissolved manganese is available as a redox product, and as such, is indicative of low-oxygen conditions. Here we present evidence for that mechanism in a range of habitats from marine to freshwater, across species, and also present ancillary proxies that support the mechanism as well. For example, iodine is redox-sensitive and varies inversely with Mn; and sulfur stable isotope ratios provide evidence of anoxic sulfate reduction in some circumstances. Further, S may be incorporated trophically whereas other elements appear to be taken up directly from water. This research suggests a potential means to identify individual fish exposure to hypoxia, over entire lifetimes. With further testing and understanding, in the future fish may be able to be used as "mobile monitors" of hypoxic conditions.

  8. Composition and properties of the soluble organic matrix of the otolith of a marine fish: Gadus morhua Linne, 1758 (Teleostei, Gadidae).

    Science.gov (United States)

    Dauphin, Y; Dufour, E

    2003-03-01

    The soluble matrix of the sagittal otolith of the cod Gadus morhua was analyzed using UV and IR spectroscopy, liquid chromatography and electrophoresis. This matrix is a complex mixture of proteins and glycoproteins, with a large range of molecular weights. High weights (>1000 kDa) are shown for the first time in water-soluble matrix of otolith. However, the 2D denaturing electrophoresis and large range of sorting used in high performance liquid chromatography columns do not separate the soluble matrix to well-defined molecular weights. The IR data indicate that several conformations are present and the main part of the sugars is not sulfated. Additionally, electrophoresis data show that the acidity of the sugar components is higher than that of the proteins. Despite the relative scarcity of literature data, our study of G. morhua suggests that the chemical composition of otolith soluble organic matrix may differ among species. PMID:12600664

  9. Linking growth to environmental histories in central Baltic young-of-the-year sprat, Sprattus sprattus : an approach based on otolith microstructure analysis and hydrodynamic modelling

    DEFF Research Database (Denmark)

    Baumann, H.; Hinrichsen, H.H.; Voss, R.; Stepputtis, D.; Grygiel, W.; Worsøe Clausen, Lotte; Temming, A.

    2006-01-01

    Otolith microstructure analysis and hydrodynamic modelling were combined to study growth patterns in young-of-the-year (YoY) sprat, Sprattus sprattus, which were sampled in October 2002 in the central Baltic Sea. The observed 'window of survival', approximated by the distribution of back...... predominantly comprised of individuals which grew faster during the larval stage. Daily mean temperatures, experienced across the entire YoY population, were derived from Lagrangian particle simulations and correlated with (1) detrended otolith growth and (2) back-calculated, daily somatic growth rates of...... survivors. The results showed that abrupt changes in ambient temperature can be detected in the seasonal pattern of otolith growth, and that higher temperatures led to significantly faster growth throughout the entire age range of YoY sprat...

  10. The Otolith Group’s “Monuments to Dead Television.” Independent Cinema and the Migrant Experience in Europe between Television and the Museum

    Directory of Open Access Journals (Sweden)

    Beatrice Ferrara

    2014-04-01

    Full Text Available “Monument to dead television” is the expression the British collective The Otolith Group uses to define its activity of recuperating long-lost quality films, and re-screening them in contemporary art museums and gallery spaces. What these films share is a cinematic vocation and a complex approach to the question of memory and migration in Europe, and to the role of images as testimonies or documents. This essay explores The Otolith Group’s interest in such forgotten archives of modern television in order to unearth their significance for contemporary museums today.

  11. Radiocarbon in otoliths of yelloweye rockfish (Sebastes ruberrimus): a reference time series for the coastal waters of southeast Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Kerr-Ferrey, L A; Andrews, A H; Frantz, B R; Coale, K H; Brown, T A; Cailliet, G M

    2003-10-14

    Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon ({sup 14}C) signal in the environment that has provided a useful tracer and chronological marker in oceanic systems and organisms. The bomb-generated {sup 14}C signal retained in fish otoliths can be used as a permanent, time-specific recorder of the 14C present in ambient seawater, making it a useful tool in age validation of fishes. The goal of this study was to determine {sup 14}C levels in otoliths of the age-validated yelloweye rockfish (Sebastes ruberrimus) to establish a reference time series for the coastal waters of southeast Alaska. Radiocarbon values from the first year's growth of 43 yelloweye rockfish otoliths were plotted against estimated birth year to produce a 14C time series for these waters spanning 1940 to 1990. The time series shows the initial rise of bomb 14C occurred in 1958 in coastal southeast Alaskan waters and {sup 14}C levels rose relatively rapidly to peak {Delta}{sup 14}C values (60-70%) between 1966 and 1971, with a subsequent declining trend through the end of the record in 1990 (-3.2%). In addition, the radiocarbon data, independent of the radiometric study, confirms the longevity of the yelloweye rockfish up to a minimum of 44 years and strongly supports higher age estimates. The yelloweye rockfish record provides a {sup 14}C chronology that will be useful for the interpretation of {sup 14}C accreted in biological samples from these waters and in future rockfish age validation studies.

  12. The mangrove nursery paradigm revisited: otolith stable isotopes support nursery-to-reef movements by Indo-Pacific fishes.

    Directory of Open Access Journals (Sweden)

    Ismael A Kimirei

    Full Text Available Mangroves and seagrass beds have long been perceived as important nurseries for many fish species. While there is growing evidence from the Western Atlantic that mangrove habitats are intricately connected to coral reefs through ontogenetic fish migrations, there is an ongoing debate of the value of these coastal ecosystems in the Indo-Pacific. The present study used natural tags, viz. otolith stable carbon and oxygen isotopes, to investigate for the first time the degree to which multiple tropical juvenile habitats subsidize coral reef fish populations in the Indo Pacific (Tanzania. Otoliths of three reef fish species (Lethrinus harak, L. lentjan and Lutjanus fulviflamma were collected in mangrove, seagrass and coral reef habitats and analyzed for stable isotope ratios in the juvenile and adult otolith zones. δ(13C signatures were significantly depleted in the juvenile compared to the adult zones, indicative of different habitat use through ontogeny. Maximum likelihood analysis identified that 82% of adult reef L. harak had resided in either mangrove (29% or seagrass (53% or reef (18% habitats as juveniles. Of adult L. fulviflamma caught from offshore reefs, 99% had passed through mangroves habitats as juveniles. In contrast, L. lentjan adults originated predominantly from coral reefs (65-72% as opposed to inshore vegetated habitats (28-35%. This study presents conclusive evidence for a nursery role of Indo-Pacific mangrove habitats for reef fish populations. It shows that intertidal habitats that are only temporarily available can form an important juvenile habitat for some species, and that reef fish populations are often replenished by multiple coastal habitats. Maintaining connectivity between inshore vegetated habitats and coral reefs, and conserving habitat mosaics rather than single nursery habitats, is a major priority for the sustainability of various Indo Pacific fish populations.

  13. San Francisco Estuary Striped Bass Migration History Determined by Electron-microprobe Analysis of Otolith Sr/Ca Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Ostrach, D J; Phillis, C C; Weber, P K; Ingram, B L; Zinkl, J G

    2004-09-17

    Habitat use has been shown to be an important factor in the bioaccumulation of contaminants in striped bass. This study examines migration in striped bass as part of a larger study investigating bioaccumulation and maternal transfer of xenobiotics to progeny in the San Francisco Estuary system. Habitat use, residence time and spawning migration over the life of females (n = 23) was studied. Female striped bass were collected between Knights Landing and Colusa on the Sacramento River during the spawning runs of 1999 and 2001. Otoliths were removed, processed and aged via otolith microstructure. Subsequently, otoliths were analyzed for strontium/calcium (Sr/Ca) ratio using an electron-microprobe to measure salinity exposure and to distinguish freshwater, estuary, and marine habitat use. Salinity exposure during the last year before capture was examined more closely for comparison of habitat use by the maternal parent to contaminant burden transferred to progeny. Results were selectively confirmed by ion microprobe analyses for habitat use. The Sr/Ca data demonstrate a wide range of migratory patterns. Age of initial ocean entry differs among individuals before returning to freshwater, presumably to spawn. Some fish reside in freshwater year-round, while others return to more saline habitats and make periodic migrations to freshwater. Frequency of habitat shifts and residence times differs among fish, as well as over the lifetime of individual fish. While at least one fish spent its final year in freshwater, the majority of spawning fish spent their final year in elevated salinity. However, not all fish migrated to freshwater to spawn in the previous year. Results from this investigation concerning migration history in striped bass can be combined with contaminant and histological developmental analyses to better understand the bioaccumulation of contaminants and the subsequent effects they and habitat use have on fish populations in the San Francisco Estuary system.

  14. Water temperature and fish growth: otoliths predict growth patterns of a marine fish in a changing climate.

    Science.gov (United States)

    Rountrey, Adam N; Coulson, Peter G; Meeuwig, Jessica J; Meekan, Mark

    2014-08-01

    Ecological modeling shows that even small, gradual changes in body size in a fish population can have large effects on natural mortality, biomass, and catch. However, efforts to model the impact of climate change on fish growth have been hampered by a lack of long-term (multidecadal) data needed to understand the effects of temperature on growth rates in natural environments. We used a combination of dendrochronology techniques and additive mixed-effects modeling to examine the sensitivity of growth in a long-lived (up to 70 years), endemic marine fish, the western blue groper (Achoerodus gouldii), to changes in water temperature. A multi-decadal biochronology (1952-2003) of growth was constructed from the otoliths of 56 fish collected off the southwestern coast of Western Australia, and we tested for correlations between the mean index chronology and a range of potential environmental drivers. The chronology was significantly correlated with sea surface temperature in the region, but common variance among individuals was low. This suggests that this species has been relatively insensitive to past variations in climate. Growth increment and age data were also used in an additive mixed model to predict otolith growth and body size later this century. Although growth was relatively insensitive to changes in temperature, the model results suggested that a fish aged 20 in 2099 would have an otolith about 10% larger and a body size about 5% larger than a fish aged 20 in 1977. Our study shows that species or populations regarded as relatively insensitive to climate change could still undergo significant changes in growth rate and body size that are likely to have important effects on the productivity and yield of fisheries. PMID:24862838

  15. Evaluation of Response Patterns in Somatic and Otolith Features of Laboratory- Reared and Wild Clarias gariepinus Exposed to Industrial Effluent

    OpenAIRE

    Adeogun, Aina O.; Taofeek A. Babatunde; Azubuike V. Chukwuka

    2013-01-01

    This study was aimed at comparing the responses of somatic and otolith features in Clarias gariepinus under chronic exposure conditions to industrial effluents in the laboratory for 60 days and in the wild for 6 months. Fish were collected upstream and downstream bi-monthly from a river receiving composite mixtures of industrial effluent while laboratory-rearedC. gariepinus were exposed to the same effluent mixtures in 60 days static renewal/bioassay using concentrations of 6.11, 3.05 and 2.2...

  16. Life history traits of the fish community in Lake Annecy: evidence from the stable isotope composition of otoliths

    Directory of Open Access Journals (Sweden)

    Gerdeaux D.

    2015-01-01

    Full Text Available Stable isotope analysis (SIA of fish otoliths shows great potential for exploring the ecology of fish, but this method has not been applied to the study of lacustrine fish communities. Both sequential and whole-otolith SIAs were performed on six fish species of Lake Annecy and their results compared to muscle SIA. The first purpose of these investigations was to test the use of δ18Ooto values for reconstructing fish thermal history and delimiting spatial distribution in a stratified lake. Comparison of species-specific fractionation equations and the general equation developed for freshwater fishes showed that the general one was the best suited for thermal estimation of Lake Annecy fishes and suggested that inter-specific differences or specific “vital effects” are not the only reason for apparent difference in fractionation. Thermal estimations based on SIA were consistent with descriptions of thermal habitats in the literature, except in the case of roach (Rutilus rutilus. Based on the current results, roach appears to live in a colder habitat than do perch (Perca fluviatilis. The high water transparency and thermal stratification of Lake Annecy could explain this distribution. Moreover, perch juveniles were found to live in two different thermal niches. This finding highlights the great plasticity of the species. Second, the potential use of δ13Coto values to reconstruct variation in diet and metabolism was assessed. The proportion of metabolic carbon (M contributing to otolith carbon varies markedly among species. Comparison with δ13Cmuscle values shows no direct relationship between δ13Coto and diet at either the intra-individual or the inter-specific level. A strong linear relationship between either M or the isotopic offset between otolith and muscle (Δδ13Coto - muscle and δ18Ooto values was found; this relationship reveals the dependence of M on the ambient temperature at which the species occurs. This relationship might be

  17. 210Pb/226Ra disequilibria in otoliths of blue grenadier, (Macruronus novaezelandiae); problems associated with radiometric aging

    International Nuclear Information System (INIS)

    Otoliths from blue grenadier (Macruronus novaezelandiae), which had been aged previously by annuli analysis, were analysed for the naturally occurring radionuclides 210Pb and 226Ra in an attempt to independently verify their age. It is concluded that the radiometric technique could not be applied to determine age because the results showed that 226Ra was not incorporated at a constant rate throughout the life of M. novaezelandiae. Uptake of 226Ra was greater in juveniles than in adult fish. This was probably due to the juvenile phase inhabiting inshore/estuarine waters. 20 refs., 1 tab., 2 figs

  18. Head movements suggest canal and otolith projections are activated during galvanic vestibular stimulation.

    Science.gov (United States)

    Kim, J

    2013-12-01

    Three-dimensional changes in the angular orientation of the head were monitored during galvanic vestibular stimulation (GVS) delivered through electrodes implanted bilaterally in the tensor tympani muscle of the guinea-pig middle ear. Bilateral GVS was delivered by passing current between both ears with the anode situated in one ear and the cathode in the other ear. Unilateral GVS was also delivered between one ear and an indifferent electrode on the skull. Constant-current stimulation caused the head to tilt predominantly within the roll and yaw planes toward an ear stimulated with anodal current and away from an ear stimulated with cathodal current. No significant head tilt in the pitch plane was observed with either bilateral or unilateral GVS. Bilateral GVS was found to induce significantly greater roll head tilt (RHT) and yaw head tilt (YHT) than the same intensity of unilateral anodal or cathodal GVS, but not the sum of responses induced by the two polarities of unilateral GVS. Significant asymmetries were observed in the responses of YHT and RHT for unilateral anodal and cathodal GVS; unilateral cathodal stimulation generated greater head deviation compared with the same intensity of unilateral anodal stimulation. These asymmetric responses are consistent with activation of irregularly discharging afferents, which have been shown previously to exhibit asymmetric responses for anodal and cathodal GVS (Kim and Curthoys, 2004). Together with the observations of previous guinea-pig studies, the results suggest that head movements induced by GVS may be mediated by irregularly discharging afferents innervating the otoliths, and possibly the horizontal semicircular canals. PMID:24021920

  19. Use of otoliths to estimate size at sexual maturity in fish

    Directory of Open Access Journals (Sweden)

    Carlos Sérgio Agostinho

    2000-01-01

    Full Text Available The viability of an alternative method for estimating the size at sexual maturity of females of Plagioscion squamosissimus (Perciformes, Sciaenidae was analyzed. This methodology was used to evaluate the size at sexual maturity in crabs, but has not yet been used for this purpose in fishes. Separation of young and adult fishes by this method is accomplished by iterative adjustment of straight-line segments to the data for length of the otolith and length of the fish. The agreement with the estimate previously obtained by another technique and the possibility of calculating the variance indicates that in some cases, the method analyzed can be used successfully to estimate size at sexual maturity in fish. However, additional studies are necessary to detect possible biases in the method.A viabilidade de uma metologia alternativa para a estimativa do tamanho de maturação sexual de fêmeas de Plagioscion squamosissimus (Perciformes, Sciaenidae foi analisada. Esta metodologia tem sido utilizada para avaliar o tamanho da maturação sexual em caranguejos mas ainda não havia sido utilizada em peixes com este objetivo. A separação dos peixes jovens e adultos por este método é feita pelo ajuste iterativo de segmentos de reta aos dados de comprimento do otólito e comprimento do peixe. A concordância com a estimativa obtida previamente utilizando outra técnica e a possibilidade do cálculo da variância indica que em alguns casos o método analisado pode ser utilizado com sucesso para estimar o tamanho de maturação sexual em peixes, mas outros estudos são necessários para se detectar possíveis bias do método.

  20. Use of otolith strontium:calcium and zinc:calcium ratios as an indicator of the habitat of Percophis brasiliensis Quoy & Gaimard, 1825 in the southwestern Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    Esteban Avigliano

    2015-03-01

    Full Text Available We evaluate the simultaneous use of Sr: Ca and Zn: Ca ratios of the sagitta otolith as a potential indicator of the habitat of Percophis brasiliensis along a latitudinal gradient in the southwestern Atlantic Ocean (34-42ºS and 51-67ºW, in order to reliably identify fish stocks. Fish were collected in three sampling sites: Argentine-Uruguayan Common Fishing Zone (AUCFZ, El Rincón (ER and San Matías Gulf (SMG. The otolith Sr:Ca and Zn:Ca ratios were determined by ICP-OES and EDTA volumetric method. The otolith Sr:Ca ratio was similar in the three sampling sites, while the Zn:Ca ratio was significantly higher in AUCFZ than in ER and SMG for all age groups. The discriminant analysis showed an association between the otolith Sr:Ca and Zn:Ca ratios from ER and SMG. Present results suggest the potential occurrence of two fish stocks of P. brasiliensis in the study area.

  1. Is otolith microchemistry (Sr: Ca and Ba:Ca ratios) useful to identify Mugil curema populations in the southeastern Caribbean Sea?

    Science.gov (United States)

    Avigliano, E; Callicó-Fortunato, R; Buitrago, J; Volpedo, A V

    2015-11-01

    The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area. PMID:26628220

  2. A novel length back-calculation approach accounting for ontogenetic changes in the fish length - otolith size relationship during the early life of sprat (Sprattus sprattus)

    DEFF Research Database (Denmark)

    Guenther, Claudia C.; Temming, Axel; Baumann, Hannes;

    2012-01-01

    An individual-based length back-calculation method was developed for juvenile Baltic sprat (Sprattus sprattus), accounting for ontogenetic changes in the relationship between fish length and otolith length. In sprat, metamorphosis from larvae to juveniles is characterized by the coincidence of low......, which is supposed to be critical in determining recruitment strength in Baltic sprat....

  3. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus elucidated by otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Michio Fukushima

    Full Text Available The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus, two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr and barium (Ba showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  4. Daily growth increments in otoliths of juvenile black rockfish, Sebastes melanops: an evaluation of autoradiography as a new method of validation

    International Nuclear Information System (INIS)

    This study evaluates the commonly used oxytetracycline hydrochloride (OTC) and an alternate chemical, the radioisotope calcium-45, in terms of their success as time-markers to validate daily growth increment formation in the otoliths of juvenile black rockfish, Sebastes melanops

  5. Geographical origin of Amazonian freshwater fishes fingerprinted by ⁸⁷Sr/⁸⁶Sr ratios on fish otoliths and scales.

    Science.gov (United States)

    Pouilly, Marc; Point, David; Sondag, Francis; Henry, Manuel; Santos, Roberto V

    2014-08-19

    Calcified structures such as otoliths and scales grow continuously throughout the lifetime of fishes. The geochemical variations present in these biogenic structures are particularly relevant for studying fish migration and origin. In order to investigate the potential of the (87)Sr/(86)Sr ratio as a precise biogeochemical tag in Amazonian fishes, we compared this ratio between the water and fish otoliths and scales of two commercial fish species, Hoplias malabaricus and Schizodon fasciatus, from three major drainage basins of the Amazon: the Madeira, Solimões, and Tapajós rivers, displaying contrasted (87)Sr/(86)Sr ratios. A comparison of the (87)Sr/(86)Sr ratios between the otoliths and scales of the same individuals revealed similar values and were very close to the Sr isotopic composition of the local river where they were captured. This indicates, first, the absence of Sr isotopic fractionation during biological uptake and incorporation into calcified structures and, second, that scales may represent an interesting nonlethal alternative for (87)Sr/(86)Sr ratio measurements in comparison to otoliths. Considering the wide range of (87)Sr/(86)Sr variations that exist across Amazonian rivers, we used variations of (87)Sr/(86)Sr to discriminate fish origin at the basin level, as well as at the sub-basin level between the river and savannah lakes of the Beni River (Madeira basin). PMID:24971992

  6. Beyond the transect: an alternative microchemical imaging method for fine scale analysis of trace elements in fish otoliths during early life.

    Science.gov (United States)

    McGowan, Nicole; Fowler, Ashley M; Parkinson, Kerryn; Bishop, David P; Ganio, Katherine; Doble, Philip A; Booth, David J; Hare, Dominic J

    2014-10-01

    Microchemical analysis of otolith (calcified 'ear stones' used for balance and orientation) of fishes is an important tool for studying their environmental history and management. However, the spatial resolution achieved is often too coarse to examine short-term events occurring in early life. Current methods rely on single points or transects across the otolith surface, which may provide a limited view of elemental distributions, a matter that has not previously been investigated. Imaging by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) permits microchemical analyses of short-term events in early life with high (97% was achieved using a multi-point non matrix-matched calibration of National Institute of Standards and Technology (NIST) 610 and 612 (trace elements in glass) using Longerich's calculation method against the matrix-matched standard FEBS-1 (powdered red snapper [Lutjanus campechanus] otolith). The spatial resolution achieved in the otolith corresponded to a time period of 2 ± 1 days during the larval phase, and 4 ± 1 days during the post-settlement juvenile phase. This method has the potential to improve interpretations of early life-history events at scales corresponding to specific events. While the images showed gradients in Sr and Ba across the larval settlement zone more clearly than single transects, the method proved sample homogeneity throughout the structure; demonstrating that 2D scanning has no significant advantage over line scans. PMID:25046609

  7. Vestibulo-Ocular Responses to Vertical Translation using a Hand-Operated Chair as a Field Measure of Otolith Function

    Science.gov (United States)

    Wood, S. J.; Campbell, D. J.; Reschke, M. F.; Prather, L.; Clement, G.

    2016-01-01

    The translational Vestibulo-Ocular Reflex (tVOR) is an important otolith-mediated response to stabilize gaze during natural locomotion. One goal of this study was to develop a measure of the tVOR using a simple hand-operated chair that provided passive vertical motion. Binocular eye movements were recorded with a tight-fitting video mask in ten healthy subjects. Vertical motion was provided by a modified spring-powered chair (swopper.com) at approximately 2 Hz (+/- 2 cm displacement) to approximate the head motion during walking. Linear acceleration was measured with wireless inertial sensors (Xsens) mounted on the head and torso. Eye movements were recorded while subjects viewed near (0.5m) and far (approximately 4m) targets, and then imagined these targets in darkness. Subjects also provided perceptual estimates of target distances. Consistent with the kinematic properties shown in previous studies, the tVOR gain was greater with near targets, and greater with vision than in darkness. We conclude that this portable chair system can provide a field measure of otolith-ocular function at frequencies sufficient to elicit a robust tVOR.

  8. The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish.

    Science.gov (United States)

    Wenger, Amelia S; Whinney, James; Taylor, Brett; Kroon, Frederieke

    2016-01-01

    Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change. PMID:27350589

  9. Micro-PIXE analysis of strontium in Arctic char, Salvelinus alpinus, otoliths from Quttinirpaaq National Park, Nunavut, Canada

    International Nuclear Information System (INIS)

    Arctic char, Salvelinus alpinus, exhibit either lake resident or anadromous (sea-run) life histories. Anadromy is less prevalent at the northern and southern extremes of the distribution. Effective conservation and management of char requires knowledge of life histories exhibited by individuals and populations. Micro-PIXE line-scans were used to determine the distribution of strontium (Sr) in otoliths from which life history patterns were determined for Arctic char from 10 lakes in Quttinirpaaq National Park in the Canadian High Arctic. Although most populations were lake resident as expected, the data indicated that a component of the char population from one lake was anadromous. This represents the most northerly known char population to exhibit anadromy. Mean Sr concentrations in otoliths of char from all populations, as determined by point analysis and also from line-scan data, showed no significant differences between the methods. Mean Sr concentrations (from point analysis) showed significant differences between some of the populations. These differences combined with other analyses (e.g. morphometrics, genetics) can be used to differentiate biological populations. Thus, micro-PIXE analysis is a useful tool for assessing diversity in Arctic char and contributing to their management and conservation in the park

  10. Evidence of estuarine nursery origin of five coastal fish species along the Portuguese coast through otolith elemental fingerprints

    Science.gov (United States)

    Vasconcelos, Rita P.; Reis-Santos, Patrick; Tanner, Susanne; Maia, Anabela; Latkoczy, Christopher; Günther, Detlef; Costa, Maria José; Cabral, Henrique

    2008-08-01

    Connectivity is a critical property of marine populations, particularly for species with segregated juvenile and adult habitats. Knowledge of this link is fundamental in understanding population structure and dynamics. Young adults of commercially important fish species Solea solea, Solea senegalensis, Platichthys flesus, Diplodus vulgaris and Dicentrarchus labrax were sampled off the Portuguese coast in order to establish preliminary evidence of estuarine nursery origins through otolith elemental fingerprints. Concentrations of Li, Na, Mg, K, Mn, Cu, Zn, Sr, Ba and Pb in the otolith section corresponding to juvenile's nursery life period were determined through laser ablation inductively coupled plasma mass spectrometry. Element: Ca ratios in coastal fish differed significantly amongst collection areas, except for Platichthys flesus, and were compared with the elemental fingerprints previously defined for age 0 juveniles in the main estuarine nurseries of the Portuguese coast. Identification of nursery estuaries was achieved for four of the species. Assigned nursery origins varied amongst species and differences in the spatial scale of fish dispersal were also found. Diplodus vulgaris was not reliably assigned to any of the defined nurseries. Overall, results give evidence of the applicability of estuarine habitat tags in future assessments of estuarine nursery role. Research developments on the links between juvenile and adult habitats should contribute for the integrated management and conservation of nurseries and coastal stocks.

  11. Sensory perception. [role of human vestibular system in dynamic space perception and manual vehicle control

    Science.gov (United States)

    1974-01-01

    The effect of motion on the ability of men to perform a variety of control actions was investigated. Special attention was given to experimental and analytical studies of the dynamic characteristics of the otoliths and semicircular canals using a two axis angular motion simulator and a one axis linear motion simulator.

  12. Vestibular Stimulation for ADHD: Randomized Controlled Trial of Comprehensive Motion Apparatus

    Science.gov (United States)

    Clark, David L.; Arnold, L. Eugene; Crowl, Lindsay; Bozzolo, Hernan; Peruggia, Mario; Ramadan, Yaser; Bornstein, Robert; Hollway, Jill A.; Thompson, Susan; Malone, Krista; Hall, Kristy L.; Shelton, Sara B.; Bozzolo, Dawn R.; Cook, Amy

    2008-01-01

    Objective: This research evaluates effects of vestibular stimulation by Comprehensive Motion Apparatus (CMA) in ADHD. Method: Children ages 6 to 12 (48 boys, 5 girls) with ADHD were randomized to thrice-weekly 30-min treatments for 12 weeks with CMA, stimulating otoliths and semicircular canals, or a single-blind control of equal duration and…

  13. Beyond the transect: An alternative microchemical imaging method for fine scale analysis of trace elements in fish otoliths during early life

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Nicole [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); CCFS ARC Centre of Excellence, Department of Earth and Planetary Sciences, Macquarie University, Sydney (Australia); Fowler, Ashley M.; Parkinson, Kerryn [Fish Ecology Laboratory, School of the Environment, University of Technology, Sydney, New South Wales (Australia); Bishop, David P. [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Ganio, Katherine [Florey Department of Neuroscience and Mental Health, University of Melbourne, Victoria (Australia); Doble, Philip A. [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Booth, David J. [Fish Ecology Laboratory, School of the Environment, University of Technology, Sydney, New South Wales (Australia); Hare, Dominic J., E-mail: dominic.hare@uts.edu.au [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Florey Department of Neuroscience and Mental Health, University of Melbourne, Victoria (Australia)

    2014-10-01

    Microchemical analysis of otolith (calcified ‘ear stones’ used for balance and orientation) of fishes is an important tool for studying their environmental history and management. However, the spatial resolution achieved is often too coarse to examine short-term events occurring in early life. Current methods rely on single points or transects across the otolith surface, which may provide a limited view of elemental distributions, a matter that has not previously been investigated. Imaging by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) permits microchemical analyses of short-term events in early life with high (< 10 μm) resolution, two-dimensional (2D) visualization of elemental distributions. To demonstrate the potential of this method, we mapped the concentrations of Sr and Ba, two key trace elements, in a small number of juvenile otoliths of neon damselfish (Pomacentrus coelestis) using an 8 μm beam diameter (laser fluence of 13.8 ± 3.5 J cm{sup −2}). Quantification was performed using the established method by Longerich et al. (1996), which is applied to 2D imaging of a biological matrix here for the first time. Accuracy of > 97% was achieved using a multi-point non matrix-matched calibration of National Institute of Standards and Technology (NIST) 610 and 612 (trace elements in glass) using Longerich's calculation method against the matrix-matched standard FEBS-1 (powdered red snapper [Lutjanus campechanus] otolith). The spatial resolution achieved in the otolith corresponded to a time period of 2 ± 1 days during the larval phase, and 4 ± 1 days during the post-settlement juvenile phase. This method has the potential to improve interpretations of early life-history events at scales corresponding to specific events. While the images showed gradients in Sr and Ba across the larval settlement zone more clearly than single transects, the method proved sample homogeneity throughout the structure; demonstrating that 2D

  14. Beyond the transect: An alternative microchemical imaging method for fine scale analysis of trace elements in fish otoliths during early life

    International Nuclear Information System (INIS)

    Microchemical analysis of otolith (calcified ‘ear stones’ used for balance and orientation) of fishes is an important tool for studying their environmental history and management. However, the spatial resolution achieved is often too coarse to examine short-term events occurring in early life. Current methods rely on single points or transects across the otolith surface, which may provide a limited view of elemental distributions, a matter that has not previously been investigated. Imaging by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) permits microchemical analyses of short-term events in early life with high (< 10 μm) resolution, two-dimensional (2D) visualization of elemental distributions. To demonstrate the potential of this method, we mapped the concentrations of Sr and Ba, two key trace elements, in a small number of juvenile otoliths of neon damselfish (Pomacentrus coelestis) using an 8 μm beam diameter (laser fluence of 13.8 ± 3.5 J cm−2). Quantification was performed using the established method by Longerich et al. (1996), which is applied to 2D imaging of a biological matrix here for the first time. Accuracy of > 97% was achieved using a multi-point non matrix-matched calibration of National Institute of Standards and Technology (NIST) 610 and 612 (trace elements in glass) using Longerich's calculation method against the matrix-matched standard FEBS-1 (powdered red snapper [Lutjanus campechanus] otolith). The spatial resolution achieved in the otolith corresponded to a time period of 2 ± 1 days during the larval phase, and 4 ± 1 days during the post-settlement juvenile phase. This method has the potential to improve interpretations of early life-history events at scales corresponding to specific events. While the images showed gradients in Sr and Ba across the larval settlement zone more clearly than single transects, the method proved sample homogeneity throughout the structure; demonstrating that 2D scanning

  15. Daily otolith growth and ontogenetic geochemical signatures of age-0 anchovy (Engraulis encrasicolus in the Gulf of Cádiz (SW Spain.

    Directory of Open Access Journals (Sweden)

    I. A. CATALÁN

    2015-01-01

    Full Text Available The European anchovy fishery in the Gulf of Cádiz (ICES Division IXa South is largely influenced by age-0 individuals. Knowledge of young of the year growth dynamics is crucial for management, yet data on daily growth are lacking in the area. Linking growth patterns to the environment requires information on habitat occupancy through ontogeny of the fish that reach the fishery, as anchovy use different areas of the Gulf and the Guadalquivir Estuary through development. We describe the growth dynamics of age-0 anchovy through otolith microstructure analysis, and couple these data with data on microchemical signals in the otoliths to shed light into habitat use and growth dynamics in the area. Age-0 anchovy captured in September, 2011 in the Gulf ranged from 3 to 6 months old for similar sizes, with average growth rates varying twofold. Individual non-linear growth curves showed that maximum otolith growth was positively correlated with the date of spawning, which in turn was negatively correlated with the time to reach maximum growth. There was no correlation between growth parameters and body length or condition (Fulton K at capture. The strontium:calcium (Sr/Ca and magnesium:calcium (Mg/Ca ratios were significantly lower at the edge of the otolith (approximately the age of capture than at ages corresponding to larval and early juveniles (<60 days old, but values fell within typical estuarine-dwelling species. The barium:calcium ratio (Ba/Ca increased significantly in the edge of the otolith, which possibly resulted from residency in highly productive coastal waters or from ontogenetic effects. The variance in otolith elemental ratios was larger at otolith back-calculated ages around 50 days old, age which coincides with the presumed closer dependence of estuarine waters. Our data are a first step towards understanding the contribution of the estuarine system to the fishery of anchovy in the Gulf. The limitations of the approach and future

  16. Effects of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops from laboratory experiment studies from 2011-08-24 to 2011-10-19 (NODC Accession 0117506)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains laboratory experiment data that were collected to examine the effects of elevated levels of CO2 on the growth, survival, otolith (ear...

  17. Stable isotopes from Benthic foraminifera and Fish otoliths as proxies for Orbital Climate Forcing and Seasonality Changes during the Middle Eocene to Late Oligocene in the shallow marine North Sea Basin

    Science.gov (United States)

    de Man, Ellen; Ivany, Linda; van Simaeys, Stefaan; Steurbaut, Etienne; Vandenberghe, Noel

    2010-05-01

    Stable isotopes from Benthic foraminifera and Fish otoliths as proxies for Orbital Climate Forcing and Seasonality Changes during the Middle Eocene to Late Oligocene in the shallow marine North Sea Basin

  18. An otolith microchemistry study of possible relationships between the origins of leptocephali of European eels in the Sargasso Sea and the continental destinations and relative migration success of glass eels

    OpenAIRE

    Martin, J; Daverat, F.; C. Pécheyran; Als, T. D.; FEUNTEUN E.; Réveillac, E.

    2010-01-01

    Little is known about the extent to which Atlantic eels coming from different European rivers converge on the same spawning site. Our aim was to evaluate the spatial homogeneity of eel spawning area(s) with an otolith microchemistry approach. This work compared the elemental signatures of otolith's core region of Anguilla anguilla leptocephali caught in the Sargasso Sea in 2007 with those of glass eels and elvers sampled in European estuaries during 2006, 2008 and 2009. Using laser ablation i...

  19. Otolith analysis of pre-restoration habitat use by Chinook salmon in the delta-flats and nearshore regions of the Nisqually River Estuary

    Science.gov (United States)

    Lind-Null, Angie; Larsen, Kim

    2010-01-01

    The Nisqually Fall Chinook population is one of 27 salmon stocks in the Puget Sound (Washington) evolutionarily significant unit listed as threatened under the federal Endangered Species Act (ESA). Extensive restoration of the Nisqually River delta ecosystem is currently taking place to assist in recovery of the stock as juvenile Fall Chinook salmon are dependent on the estuary. A pre-restoration baseline that includes the characterization of life history strategies, estuary residence times, growth rates, and habitat use is needed to evaluate the potential response of hatchery and natural origin Chinook salmon to restoration efforts and to determine restoration success. Otolith analysis was selected as a tool to examine Chinook salmon life history, growth, and residence in the Nisqually River estuary. Previously funded work on samples collected in 2004 (marked and unmarked) and 2005 (unmarked only) partially established a juvenile baseline on growth rates and length of residence associated with various habitats (freshwater, forested riverine tidal, emergent forested transition, estuarine emergent marsh, delta-flats and nearshore). However, residence times and growth rates for the delta-flats (DF) and nearshore (NS) habitats have been minimally documented due to small sample sizes. The purpose of the current study is to incorporate otolith microstructural analysis using otoliths from fish collected within the DF and NS habitats during sampling years 2004-08 to increase sample size and further evaluate between-year variation in otolith microstructure. Our results from this analysis indicated the delta-flats check (DFCK) on unmarked and marked Chinook samples in 2005-08 varied slightly in appearance from that seen on samples previously analyzed only from 2004. A fry migrant life history was observed on otoliths of unmarked Chinook collected in 2005, 2007, and 2008. Generally, freshwater mean increment width of unmarked fish, on average, was smaller compared to marked

  20. OTOLITH MICROCHEMISTRY INDICATES UNEXPECTED PATTERNS OF RESIDENCY AND ANADROMY IN BLUEBACK HERRING, ALOSA AESTIVALIS, IN THE HUDSON AND MOHAWK RIVERS.

    Directory of Open Access Journals (Sweden)

    LIMBURG K. E.

    2001-07-01

    PIXE, providing a detailed time series of data on the Sr:Ca, and thus habitat use history, of the fish. We also analyzed otoliths of Mohawk and Hudson River young-of-year (YOY. The Sr:Ca ratios of Mohawk YOY are slightly but significantly higher than those of Hudson YOY. Life history transects for 51 adults show complex patterns of Sr:Ca, indicating that many of the fish move into salt water at least for brief periods. However, many fish appear to spend extended parts of their post-YOY lives in fresh water, and at least two adults (caught in the Mohawk near Rome, NY appear never to have changed habitats at all. This is thus the first demonstration of residency in Mohawk River herring.

  1. Estudo preliminar da utilização de otólitos de Cynoscion acoupa sobre o processo de neoformação óssea em ratos Preliminary study of using otoliths of Cynoscion acoupa upon the process of bone regeneration in rats

    Directory of Open Access Journals (Sweden)

    Daisy Pereira Valido

    2010-08-01

    Full Text Available INTRODUÇÃO: Otólitos são concrescências calcárias presentes no ouvido interno de peixes. Por serem ricos em minerais considerados essenciais ao processo de mineralização óssea sobre uma matriz proteica (otolina, sugere-se que otólitos poderiam funcionar como biominerais. OBJETIVO: Avaliar a capacidade de regeneração de defeitos ósseos tratados com preparado gelatinoso estéril de otólitos. MATERIAL E MÉTODO: O experimento foi realizado com 20 ratos Wistar, distribuídos aleatoriamente em dois grupos, nos quais se realizou defeito ósseo na tíbia, sendo o grupo 1 (G1 experimental, cujas lojas ósseas foram preenchidas com preparado de otólitos, e o grupo 2 (G2 controle, cujas lojas ósseas não receberam tratamento adicional. Os animais foram sacrificados 14 dias após os procedimentos cirúrgicos; as tíbias foram removidas, fixadas em formalina a 10%, descalcificadas em ácido nítrico a 5% e processadas histologicamente. Antes dos sacrifícios, foram coletadas amostras sanguíneas para avaliação das dosagens séricas de cálcio (Ca e fosfatase alcalina (Alkp. RESULTADOS: As secções histológicas revelaram que o trabeculado ósseo neoformado mostrou-se mais denso e com atividade osteorreabsortiva periosteal menos conspícua no grupo experimental. Entretanto, não demonstraram diferenças estatisticamente significativas na área de neoformação óssea entre G1 (1,9 ± 0,3 mm² e G2 (1,5 ± 0,4 mm² (p = 0,0617. Os parâmetros bioquímicos (Ca e Alkp apresentaram-se dentro dos limites de normalidade. DISCUSSÃO/CONCLUSÃO: Os dados sugerem que os otólitos podem desempenhar papel adjuvante na dinâmica da regeneração óssea.INTRODUCTION: Otoliths are calcareous concrescences present in the inner ear of fishes. Since they are rich in minerals considered essential to the bone mineralization process on a protein matrix (otolin, it has been suggested that otoliths may work as biominerals. OBJECTIVE: The objective in this study

  2. Evaluation of otolith shape as a tool for stock discrimination in marine fishes using Baltic Sea cod as a case study

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Albertsen, Christoffer Moesgaard; Eg Nielsen, Einar; Hansen, Jakob Hemmer; Eero, Margit

    2016-01-01

    In the Western Baltic Sea two genetically distinct cod stocks “Eastern Baltic cod” and “Western Balticcod” occur with considerable mixing of stocks. In this study we evaluated the applicability of otolithshape analysis for classification of individuals caught in the mixed stock cod fishery, using...... SNP (singlenucleotide polymorphism) based genetic assignment of otolith shape baselines. We further developeda management aimed approach for mixed stock assignment by robust stochastic baseline selection andposterior bias correction by individual reassignment of the least likely classifications into...... the alternatestock. Classification criteria selected by Monte Carlo runs of Linear Discriminant Analysis were capturedby otolith area and 20 Elliptic Fourier Descriptors of primarily low frequency harmonics. Classificationsuccess was considerably lower when using a baseline of spawning individuals...

  3. Micro-PIXE analysis of trace element variation in otoliths from fish collected near acid mine tailings: Potential for monitoring contaminant dispersal

    International Nuclear Information System (INIS)

    Otoliths from fish sampled proximal to acid mine tailings located near Sherridon, Manitoba contain elevated abundances of Zn, Mn, Fe and Cu. Sr is also present in amounts ranging from 250 to 1200 ppm with the actual levels dependent on the lake from which fish were taken. Previous work on analyzing Zn and Mn suggests Zn will typically vary between 50 and ∼100 ppm (in marine and non-marine species) and Mn between 10 and ∼100 ppm. Otoliths analyzed in this study contain up to ∼1000 ppm Zn and up to ∼400 ppm Mn; Fe is present, ranging between 50 and 100 ppm and Cu is typically 40-50 ppm. Water samples showed variation in these elements depending on proximity to the tailings

  4. Micro-PIXE analysis of trace element variation in otoliths from fish collected near acid mine tailings: Potential for monitoring contaminant dispersal

    Science.gov (United States)

    Saquet, M.; Halden, N. M.; Babaluk, J.; Campbell, J. L.; Nejedly, Z.

    2002-04-01

    Otoliths from fish sampled proximal to acid mine tailings located near Sherridon, Manitoba contain elevated abundances of Zn, Mn, Fe and Cu. Sr is also present in amounts ranging from 250 to 1200 ppm with the actual levels dependent on the lake from which fish were taken. Previous work on analyzing Zn and Mn suggests Zn will typically vary between 50 and ˜100 ppm (in marine and non-marine species) and Mn between 10 and ˜100 ppm. Otoliths analyzed in this study contain up to ˜1000 ppm Zn and up to ˜400 ppm Mn; Fe is present, ranging between 50 and 100 ppm and Cu is typically 40-50 ppm. Water samples showed variation in these elements depending on proximity to the tailings.

  5. Micro-PIXE analysis of trace element variation in otoliths from fish collected near acid mine tailings: Potential for monitoring contaminant dispersal

    Energy Technology Data Exchange (ETDEWEB)

    Saquet, M.; Halden, N.M. E-mail: nm_halden@umanitoba.ca; Babaluk, J.; Campbell, J.L.; Nejedly, Z

    2002-04-01

    Otoliths from fish sampled proximal to acid mine tailings located near Sherridon, Manitoba contain elevated abundances of Zn, Mn, Fe and Cu. Sr is also present in amounts ranging from 250 to 1200 ppm with the actual levels dependent on the lake from which fish were taken. Previous work on analyzing Zn and Mn suggests Zn will typically vary between 50 and {approx}100 ppm (in marine and non-marine species) and Mn between 10 and {approx}100 ppm. Otoliths analyzed in this study contain up to {approx}1000 ppm Zn and up to {approx}400 ppm Mn; Fe is present, ranging between 50 and 100 ppm and Cu is typically 40-50 ppm. Water samples showed variation in these elements depending on proximity to the tailings.

  6. PALEOBATHYMETRIC INTERPRETATION OF THE FISH OTOLITHS FROM THE LOWER - MIDDLE QUATERNARY DEPOSITS OF KEPHALLONIA AND ZAKYNTHOS ISLANDS (IONIAN SEA, WESTERN GREECE)

    OpenAIRE

    KONSTANTINA AGIADI; MARIA TRIANTAPHYLLOU; ANGELA GIRONE; VASSILIS KARAKITSIOS; MICHAEL DERMITZAKIS

    2010-01-01

    Fish otoliths are herein used to estimate the depositional depth of the Early - Middle Pleistocene deposits at SE Zakynthos and SW Kephallonia Islands (Ionian Sea, Western Greece), through comparison with the modern bathymetric distributions of the identified fish taxa. These estimates provide a more detailed picture of the depth variations for the Gelasian - Ionian stage interval in the study areas. The Lower Pleistocene marine deposits of the Gerakas Formation (SE Zakynthos Island, Ionian S...

  7. Methods for estimating a critical value for determining the freshwater/estuarine habitat residence of American eels from otolith Sr:Ca data

    Science.gov (United States)

    Jessop, B. M.; Shiao, J. C.; Iizuka, Y.

    2013-11-01

    Linear discriminant analysis (LDA) and habitat discrimination critical value (HDCV) methods are alternatives for evaluating the migratory history, such as the proportion of residence in freshwater (%fwr) and estuarine/marine habitats, of individual American eels (Anguilla rostrata) via the analysis of otolith Sr:Ca data. The LDA process requires Sr:Ca data from both freshwater and estuarine/marine groups while the mean + cSD method requires only a freshwater standard. For the two group (freshwater, estuarine/marine), single predictor variable (Sr:Ca) case, the LDA process defaults to Fisher's linear discriminant where the HDCV equals the average of the group mean Sr:Ca values. The difference between freshwater and estuarine resident eel mean otolith Sr:Ca values, based on 13 published studies and the current study (n = 14), decreased with increasing freshwater group otolith mean (r = 0.80, p sample sizes of otolith Sr:Ca values used in the discriminant process of estimating a HDCV, while statistically significant, had trivial effect sizes that were likely of little biological consequence. However, larger sample sizes are preferred over smaller sample sizes. Estimates of %fwr increased with increases in the HDCV. Differences in %fwr estimates over a range of HDCVs were highly statistically significant and effect sizes increased with increased HDCV difference. As HDCV levels increased, growth rate estimates increased for a given %fwr value. A HDCV difference of ≤0.5 × 10-3 produced a small effect size. Accurate estimation of a HDCV is fundamental to the assessment of the habitat residence and inter-habitat movement of American eels and perhaps of other diadromous fishes and helps minimize bias in dependent estimates of other useful statistics such as the percentage of freshwater residence (%fwr) and growth rate.

  8. Comparison of the elemental composition of different hard parts (otoliths, scales, fin rays, vertebrae and eye lenses) of freshwater fish using ICPMS

    Science.gov (United States)

    Kirchmaier, Leo; Irrgeher, Johanna; Prohaska, Thomas; Zitek, Andreas

    2013-04-01

    Elemental and isotopic fingerprints of different hard parts of fish are a powerful tool to gain life history information of individual fish. Most of these structures, like otoliths, scales, fin rays and vertebrae show incremental growth, allowing for a time resolved analysis of this information using e.g. laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS). Scales and fin-rays serve as important non-lethal alternatives to otoliths. Additional structures without incremental growth such as eye lenses might contain complementary information. However, there is a lack of solid matrix-matched reference materials that are needed to quantify elemental concentrations using LA-ICPMS. In this study we determined the elemental composition ("elemental fingerprint") of otoliths, scales, fin rays, vertebrae and eye lenses from freshwater fish of the Danube catchment using microwave-assisted digestion and solution based inductively coupled plasma mass spectrometry in order to gain information on the natural concentration ranges of various elements of interest in such samples. The investigation has focused on macro (Ca, Mg and P), minor and trace elements (Ba, Cu, Mn, Pb, Sr and Zn). Method validation was performed using the following certified reference materials (CRMs): riverine water (NRC SLRS-5), bone ash (NIST SRM 1400), bone meal (NIST SRM 1486) and fish otolith (NRC FEBS-1). Significant differences in elemental concentrations among different hard parts analyzed were found suggesting that different structures might be suited for a particular research purpose e.g. tracing environmental pollution. Based on this work, the preparation of in-house certified matrix-matched reference materials (co-precipitated hydroxyapatite calibration standards pressed to pellets) is established allowing for the quantification of the elemental concentration on a time resolved level in different hard parts by direct solid sampling via laser.

  9. The use of Pb-210/Ra-226 and Th-228/Ra-228 dis-equilibria in the ageing of otoliths of marine fish

    International Nuclear Information System (INIS)

    Naturally-occurring isotopes of radium are ideally suited as tracers for chemical uptake in the calcified tissues of marine organisms since radium is a water soluble, bio-geochemical analogue for calcium. Assays designed to exploit this uptake mechanism can be used to determine the longevity of certain species of fish. Measurements of Pb-210/Ra-226 disequilibria in the otoliths of redfish have revealed that this species of fish can live to ages in excess of 75 years in coastal waters off Nova Scotia, Canada. Measurements of the Th-228/Ra-228 disequilibria in the otoliths of the much shorter-lived silver hake and flying fish may provide estimates of longevity on time scales of 0-10 years, which could then be used to evaluate the accuracy of currently-used ageing models based on otolith annulus counts. Age determinations of fish based on natural radioisotopes can result in significant improvements in the assessment and management of certain fisheries resources. (author)

  10. Determination of trace elements in scallop and fish otolith by instrumental neutron activation analysis using anti-coincidence and coincidence counting methods

    International Nuclear Information System (INIS)

    Trace element concentrations in scallop reference material and fish otolith certified reference materials prepared at the National Institute for Environmental Studies (NIES) of Japan were determined by instrumental neutron activation analysis (INAA). Nine aliquots of scallop sample (ca. 252∼507 mg) and five aliquots of fish otolith sample (ca. 502 ∼ 988 mg) and comparative standards were irradiated for a short time (10 s) at a thermal neutron flux of 1.5 x 1012 n cm-2s-1 (pneumatic transfer) and for a long time (6 h) at a thermal neutron flux of 3.7 x 1012n cm-2s-1 (central thimble) in the Rikkyo University Research Reactor (100 kW). The irradiated samples were measured by conventional γ-ray spectrometry using a coaxial Ge detector, and by anti-coincidence and coincidence γ-ray spectrometry with a coaxial Ge detector and a well-type NaI (Tl) detector to determine as many trace elements as possible with high sensitivity. The concentrations of 34 elements of the NIES No.15 scallop reference material and 16 elements of the NIES No.22 fish otolith CRM were determined. Using the coincidence counting method to determine Se, Ba and Hf, the lower limit of the determination was improved by 2 times compared with the conventional counting method. (author)

  11. Morphological and biochemical analyses of otoliths of the ice-fish Chionodraco hamatus confirm a common origin with red-blooded species.

    Science.gov (United States)

    Motta, Chiara Maria; Avallone, Bice; Balassone, Giuseppina; Balsamo, Giuseppe; Fascio, Umberto; Simoniello, Palma; Tammaro, Stefania; Marmo, Francesco

    2009-01-01

    The morphology and composition of the three otoliths of the Antarctic ice-fish Chionodraco hamatus were studied by scanning electron microscopy and X-ray diffraction. The composition of the sagitta, lapillus and asteriscus protein matrices was also analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, western blots and confocal laser scanning microscopy to reveal the presence of and to localize the calcium-binding proteins calmodulin, calbindin and S-100. Morphological results indicated that the otoliths in this ice-fish were similar to those of Trematomus bernacchii, a red-blooded Antarctic species [B. Avallone et al. (2003) J. Submicrosc. Cytol. Pathol. 35, 69-76], but rather different from those of other teleosts. These two Antarctic species possessed a completely vateritic asteriscus, whereas their sagitta and lapillus were made mostly of aragonite. Parallel analysis of protein patterns in C. hamatus and T. bernacchii revealed that the sagitta significantly differed from the lapillus and asteriscus in both species. The sagitta did not contain the S-100 protein and showed calmodulin and calbindin located in discontinuous or incremental zones, respectively. These results demonstrate that the otoliths of C. hamatus and T. bernacchii share more resemblances than differences and support the idea of a common origin of these species. PMID:19166478

  12. In Situ Determination of Trace Elements in Fish Otoliths by Laser Ablation Double Focusing Sector Field Inductively Coupled Plasma Mass Spectrometry Using a Solution Standard Addition Calibration Method

    Science.gov (United States)

    Chen, Z.; Jones, C. M.

    2002-05-01

    Microchemistry of fish otoliths (fish ear bones) is a very useful tool for monitoring aquatic environments and fish migration. However, determination of the elemental composition in fish otolith by ICP-MS has been limited to either analysis of dissolved sample solution or measurement of limited number of trace elements by laser ablation (LA)- ICP-MS due to low sensitivity, lack of available calibration standards, and complexity of polyatomic molecular interference. In this study, a method was developed for in situ determination of trace elements in fish otoliths by laser ablation double focusing sector field ultra high sensitivity Finnigan Element 2 ICP-MS using a solution standard addition calibration method. Due to the lack of matrix-match solid calibration standards, sixteen trace elements (Na, Mg, P, Cr, Mn, Fe, Ni, Cu, Rb, Sr, Y, Cd, La, Ba, Pb and U) were determined using a solution standard calibration with Ca as an internal standard. Flexibility, easy preparation and stable signals are the advantages of using solution calibration standards. In order to resolve polyatomic molecular interferences, medium resolution (M/delta M > 4000) was used for some elements (Na, Mg, P, Cr, Mn, Fe, Ni, and Cu). Both external calibration and standard addition quantification strategies are compared and discussed. Precision, accuracy, and limits of detection are presented.

  13. Otolith Trace Elemental Analyses of South American Austral Hake, Merluccius australis (Hutton, 1872 Indicates Complex Salinity Structuring on their Spawning/Larval Grounds.

    Directory of Open Access Journals (Sweden)

    Paul Brickle

    Full Text Available Trace element signatures of otolith edges and cores from 335 austral hake (Merluccius autralis were analysed using LA-ICPMS from samples collected in Chilean and Falkland Islands' waters, in order to provide potential insights into stock discrimination and migrations. Fish were caught in two locations in Chile and four locations in the south-west of the Falkland Islands Shelf. Univariate and multivariate analyses of trace element signatures in the edges of otoliths, representing adult fish, were not able to distinguish between samples collected in Chile and the Falkland Islands. Cluster analyses based on Ward's similarity/distance metric suggested that it was possible to identify two groups from core signatures. Further analyses of this perceived clustering of the core concentrations revealed that this was largely due to the wide spread of Sr/Ca ratios in the otoliths' cores. Gaussian finite mixtures using MCMC methods confirmed that Sr/Ca ratios form two separate distributions with significantly different mean values while concentrations of other elements showed no evidence of the presence of two or more distributions. The results suggest that there is only one spawning stock of austral hake with spawning situated in and around the Chilean fjords (43°30'S- 47°S and the variation in Sr/Ca ratios likely suggests complex salinity structuring in this area.

  14. Otolith Trace Elemental Analyses of South American Austral Hake, Merluccius australis (Hutton, 1872) Indicates Complex Salinity Structuring on their Spawning/Larval Grounds.

    Science.gov (United States)

    Brickle, Paul; Schuchert, Pia C; Arkhipkin, Alexander I; Reid, Malcolm R; Randhawa, Haseeb S

    2016-01-01

    Trace element signatures of otolith edges and cores from 335 austral hake (Merluccius autralis) were analysed using LA-ICPMS from samples collected in Chilean and Falkland Islands' waters, in order to provide potential insights into stock discrimination and migrations. Fish were caught in two locations in Chile and four locations in the south-west of the Falkland Islands Shelf. Univariate and multivariate analyses of trace element signatures in the edges of otoliths, representing adult fish, were not able to distinguish between samples collected in Chile and the Falkland Islands. Cluster analyses based on Ward's similarity/distance metric suggested that it was possible to identify two groups from core signatures. Further analyses of this perceived clustering of the core concentrations revealed that this was largely due to the wide spread of Sr/Ca ratios in the otoliths' cores. Gaussian finite mixtures using MCMC methods confirmed that Sr/Ca ratios form two separate distributions with significantly different mean values while concentrations of other elements showed no evidence of the presence of two or more distributions. The results suggest that there is only one spawning stock of austral hake with spawning situated in and around the Chilean fjords (43°30'S- 47°S) and the variation in Sr/Ca ratios likely suggests complex salinity structuring in this area. PMID:26727274

  15. Before the flood: Miocene otoliths from eastern Amazon Pirabas Formation reveal a Caribbean-type fish fauna

    Science.gov (United States)

    Aguilera, Orangel; Schwarzhans, Werner; Moraes-Santos, Heloísa; Nepomuceno, Aguinaldo

    2014-12-01

    The Pirabas Formation of Early Miocene age represents the final stage of the central western Atlantic carbonate platform in northeastern South America, predating the emplacement of the Amazon delta system. The otolith-based fossil fish fauna is represented by 38 species typical of a shallow marine environment. A total of 18 species are described new to science from the families Congridae, Batrachoididae, Bythitidae, Sciaenidae and Paralichthyidae. The fish fauna was associated with high benthic and planktic primary productivity including seagrass meadows, calcareous algae and suspension-feeders. The break of todays shallow marine bioprovince at the Amazonas delta mouth is not evident from the fish fauna of the Pirabas Fm., which shows good correlation with the Gatunian/proto-Caribbean bioprovince known from an only slightly younger time window in Trinidad and Venezuela. Differences observed to those Early Miocene faunal associations are interpreted to be mainly due to stratigraphic and geographic and not environmental differences. We postulate that the emergence of the Amazonas river mouth close to its present day location has terminated the carbonate cycle of the Pirabas Fm. and pushed back northwards a certain proportion of the fish fauna here described.

  16. Solid phase extraction for analysis of biogenic carbonates by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS): an investigation of rare earth element signatures in otolith microchemistry

    International Nuclear Information System (INIS)

    Uptake of trace elements into fish otoliths is governed by several factors such as life histories and environment in addition to stock and species differences. In an attempt to elucidate the elemental signatures of rare earth elements (REEs) in otoliths, a solid phase extraction (SPE) protocol was used in combination with electrothermal vaporization (ETV) as a sample introduction procedure for the determinations by inductively coupled plasma quadrupole mass spectrometry (ICP-MS). Effects of various parameters, such as carrier gas flow rate, atomization temperature and chemical modification, were examined for optimization of the conditions by ETV-ICP-MS. Atomization was achieved at 2800 deg. C. Lower temperatures (i.e. 2600 deg. C) resulted in severe memory problems due to incomplete atomization. Palladium was used as a chemical modifier. It was found that an increase in Pd concentration up to 0.5 μg in the injection volume (70 μl) led up to four-fold enhancement in the integrated signals. This phenomenon is attributed to the carrier effect of Pd rather than the stabilization since no significant losses were observed for high temperature drying around 700 deg. C even in the absence of Pd. Preconcentration was performed on-line at pH 5 by using a mini-column of Toyopearl AF-Chelate 650M chelating resin, which also eliminated the calcium matrix of otolith solutions. After preconcentration of 6.4 ml of solution, the concentrate was collected in 0.65 ml of 0.5% (v/v) HNO3 in autosampler cups, and then analyzed by ETV-ICP-MS. The method was validated with the analysis of a fish otolith certified reference material (CRM) of emperor snapper, and then applied to samples. Results obtained from otoliths of fish captured in the same habitat indicated that otolith rare earth element concentrations are more dependent on environmental conditions of the habitat than on species differences

  17. Growth changes in plaice, cod, haddock and saithe in the North Sea: a comparison of (post-)medieval and present-day growth rates based on otolith measurements

    Science.gov (United States)

    Bolle, Loes J.; Rijnsdorp, Adriaan D.; van Neer, Wim; Millner, Richard S.; van Leeuwen, Piet I.; Ervynck, Anton; Ayers, Richard; Ongenae, Ellen

    2004-05-01

    Fishing effort has strongly increased in the North Sea since the mid-19th century, causing a substantial reduction in the population size of exploited fish stocks. As fisheries research has developed simultaneously with the industrialisation of the fisheries, our knowledge of population dynamics at low levels of exploitations is limited. Otoliths retrieved from archaeological excavations offer a unique opportunity to study growth rates in the past. This study compares historical and present-day growth rates for four commercially important demersal fish species. A total of 2532 modern otoliths (AD 1984-1999) and 1286 historical otoliths (AD 1200-1925) obtained from archaeological excavations in Belgium and Scotland were analysed. Comparison of the growth patterns between eras revealed a major increase in growth rate of haddock, whereas growth changes were not observed in saithe and only in the smaller size classes of plaice and cod. Comparison of our results with literature data indicates that the observed growth rate changes in plaice and cod occurred within the 20th century. Apparently the onset of industrialised fisheries has not greatly affected the growth of plaice, cod and saithe populations in the North Sea. This result contradicts the expectation of density-dependent limitation of growth during the era of pre-industrialised fishing, but is in agreement with the concentration hypothesis of Beverton (Neth. J. Sea Res. 34 (1995) 1) stating that species which concentrate spatially into nursery grounds during their early life-history may 'saturate' the carrying capacity of the juvenile habitat even though the adult part of the population is not limited by the adult habitat.

  18. Length-weight relationships and relative conditions of two sciaenids Otolithes cuvieri Trewavas and Johnius elongatus Mohan from the Karachi coast

    OpenAIRE

    Shamsul Hoda, S.M.; Ajazuddin, S.

    1993-01-01

    Estimates of length-weight relationship in Otolithes cuvieri justify separate equations for males (log W =-5.0100+3.1365 log L) and females (log W =-5.2000+3.1006 log L). Relative condition factor "Kn" was found to be 0.877-1.946 in males and 0.879-1.328 in females. High "Kn" values during March to September at 180-220 mm TL in either sexes are indicative of the maturation of gonads. Separate equations for length-weight relationship are also justified for males (log W = -5.1126 + 3.0690 log L...

  19. Some aspects of reproductive biology of two sciaenids, Otolithes cuvieri Trewavas and Johnius elongatus Mohan: maturation, spawning, sex ratio and fecundity

    OpenAIRE

    Shamsul Hoda, S.M.; Ajazuddin, S.

    1992-01-01

    The gonads of Otolithes cuvieri and Johnius elongatus are described in seven maturity stages. O. Cuvieri spawns once a year from April to September as evidence by ova diameter frequency distribution and GSI values. 50% maturity is attained at 210mm TL in males and 200mm TL in females. Fecundity ranged from 2387 to 104379 with a mean value of 33502. Log-Log relationship between fecundity and total lenght, body weight and ovary weight were determined. An overall sex ratio of 1.54:1.00 was unequ...

  20. [Isotopic composition of the delta-18O--delta-13C from the otoliths of reef fish from Taiaro (Tuamotu, French Polynesia): isotopic and biological implications].

    Science.gov (United States)

    Blamart, Dominique; Escoubeyrou, Karine; Juillet-Leclerc, Anne; Ouahdi, Rabia; Lecomte-Finiger, Raymonde

    2002-02-01

    Nuclei (larval stage) and outer parts (adult stage) of fish otoliths from the Taiaro closed lagoon (French Polynesia) and adjacent ocean have been analysed for the C-O isotopic compositions. delta 18O values of the nuclei of both populations indicate that isotopic equilibrium is reached. This implies that the lagoonal fish population has done its complete biological cycle in the lagoon and represents an adaptation in a closed system. delta 18O values of the outer parts show a slight isotopic disequilibrium (< 0.2@1000) interpreted in term of vital effect. All the delta 13C values exhibit a strong isotopic disequilibrium related to metabolic activity. PMID:11980181

  1. Glacial- interglacial temperature change based on 13C18O carbonate bond with in fish bone otoliths from Red Sea sediments

    Science.gov (United States)

    Ghosh, P.; Eiler, J.; Feeney, R.

    2006-12-01

    Determining the past record of temperature and salinity of ocean surface waters is essential for understanding past changes in climate, such as those which occur across glacial-interglacial transitions. As a useful proxy, the clumped isotope of CO2 in carbonate (13C18O16O or ?47) from inorganic precipitation experiment has been shown to reflect surface temperature with high degree of confidence (Ghosh et al., 2006). The last glacial cycle was characterized by climate fluctuations, but the extent of any associated changes in global sea level (or, equivalently, ice volume) remains elusive. High stands of sea level can be reconstructed from dated fossil and isotopic analyses of foraminifera and terapods, and these data are complemented by a compilation of global sea-level estimates based on deep-sea oxygen isotope ratios. Salinity derived from the records of oxygen isotopes ratios, however, contains uncertainties due to lack of information about the sea surface temperature change. Here we used combination of clumped isotopes technique and oxygen isotope measurement from fish otoliths (Myctophiformes; lanternfishes) extracted from two piston cores (Ku et al., 1969) (CH-154 and CH-153) to understand the temperature evolution and salinity variation of Red Sea water (300-800m) during the last 70 k.y. We analyzed well preserved unaltered otoliths from 7 different stratigraphic horizons from sediment core CH-154. Our preliminary observation suggests ~20 degree Celsius differences in sea water temperatures between glacial and interglacial time. We showed that the region has experienced fluctuation in climatic and tectonic processes during glacial interglacial time and the otoliths developed within the fishes captured the information about temperature change and salinity variation. Our results indicate a drop in temperature and restricted exchange of water with the open ocean during glaciations. The Red Sea environment was also highly saline even during the interglacial event

  2. Stable isotope compositions (O-C) of reef fish otoliths from the Taiaro lagoon (Tuamotu, French Polynesia): isotopic and biologic implications

    International Nuclear Information System (INIS)

    Nuclei (larval stage) and outer parts (adult stage) of fish otoliths from the Taiaro closed lagoon (French Polynesia) and adjacent ocean have been analysed for the C-O isotopic compositions. δ18O values of the nuclei of both populations indicate that isotopic equilibrium is reached. This implies that the lagoonal fish population has done its complete biological cycle in the lagoon and represents an adaptation in a closed system. δ18O values of the outer parts show a slight isotopic disequilibrium (13C values exhibit a strong isotopic disequilibrium related to metabolic activity. (authors)

  3. Eastern Ionian Sea paleoceanographic conditions during the Plio - Pleistocene as revealed through the study of fish otoliths

    Science.gov (United States)

    Agiadi, K.; Triantaphyllou, M. V.; Girone, A.; Karakitsios, V.; Dermitzakis, M. D.

    2009-04-01

    Fish otoliths from the SE Zakynthos and SW Kephallonia islands (Eastern Ionian Sea) provide new evidence for the reconstruction of the paleoceanographic conditions during the Late Pliocene - Early Pleistocene interval. The forty - six fish taxa identified in the sediments of the study areas are separated in tropical, subtropical, temperate and subpolar ecological groups occupying surface, intermediate and deep water layers, based on their modern geographic and bathymetric distributions. During the Late Pliocene, the presence of Chlorophthalmus agassizi in the Eastern Ionian Sea probably denotes temperate oligotrophic conditions. At about 1.96 Ma B.P the high contribution of the bathypelagic Electrona risso, whose modern contribution is limited by the 10-15° C isotherms and productivity greater than 50gC/m2y (Whitehead et al., 1984), is combined with the increased presence of the deeper water species Maurolicus muelleri and Benthosema glaciale, which are mostly known from the high temperate - subpolar zones of today's oceans (Whitehead et al., 1984; Mytilineou et al., 2005). The nutrient-rich intermediate water layers at this time thus overlie colder deep waters, much like today (Malanotte-Rizzoli et al., 1997). In addition, the high abundance of representatives of the genus Diaphus could imply warmer surface conditions (Whitehead et al., 1984). The situation around 1.93 Ma, throughout the water column, is much more homogenous, signified by the introduction of Hygophum hygomii in the deeper water layers, as well as the decrease in relative abundance of Benthosema glaciale, perhaps due to a certain increase in deep water temperate. However, the most dominant species by far in the assemblage remains Ceratoscopelus maderensis, a purely temperate meso-bahtypelagic species (D'Onghia et al., 2004). At around 1.9Ma, there is a marked increase in the relative abundance of tropical taxa, namely Diaphus taaningi and Bregmaceros sp., which occupy the upper 500 meters of the

  4. Dichelyne (Dichelyne) spinigerus sp. nov. (Nematoda: Cucullanidae) from the marine fish Otolithes ruber (Sciaenidae) off Iran and first description of the male of Philometra otolithi Moravec et Manoharan, 2013 (Nematoda: Philometridae)

    Czech Academy of Sciences Publication Activity Database

    Moravec, František; Khosheghbal, M.; Pazooki, J.

    2014-01-01

    Roč. 59, č. 2 (2014), s. 229-237. ISSN 1230-2821 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : parasitic nematode * Dichelyne * Philometra * marine fish * Otolithes * Iran Subject RIV: EG - Zoology Impact factor: 0.905, year: 2014

  5. Migratory patterns of exotic brown trout Salmo trutta in south-western Hokkaido, Japan, on the basis of otolith Sr:Ca ratios and acoustic telemetry.

    Science.gov (United States)

    Honda, K; Arai, T; Kobayashi, S; Tsuda, Y; Miyashita, K

    2012-02-01

    Acoustic telemetry and microchemical analysis of otolith strontium-calcium ratios were used to evaluate how exotic brown trout Salmo trutta have responded to Japanese riverine environments of south-western Hokkaido by observing their migratory patterns. The existence of anadromous S. trutta was also verified. Most S. trutta caught in rivers for otolith analysis were freshwater residents (95·6%), whereas those caught in the sea were mainly smolts (91·3%), which had just migrated from rivers during spring. Anadromous S. trutta (n = 6) were captured in rivers and in the sea, confirming the existence of mature pre- and post-spawning fish. According to telemetry results, both mature and immature S. trutta used the river in winter, and their estimated sea-run timings showed individual differences. Through the combination of these two methods, migratory patterns on various spatio-temporal scales were observed. This first documentation of the presence of both male and female anadromous S. trutta in the same region within Japan indicated the risk of further colonization of exotic S. trutta via oceanic migration. PMID:22268438

  6. Individual Behavioral Adaptability to Diminished G-Forces and Calcium Uptake of Inner ear Otoliths in Fish. A Sounding Rocket Experiment (TX 48)

    Science.gov (United States)

    Knie, Miriam; Shcherbakov, Denis; Hilbig, Reinhard

    2013-02-01

    In the course of the TEXUS 45 experiment we were able to show that the time-course of a habituation to diminished gravity depends on the respective G-level HQM (high quality microgravity, 10-4g) vs. LQM (low quality microgravity, 10-2g) and on the symmetric morphology of the gravity sensing components of the inner ear. An individually different regulation of inner ear otolith calcification plays a role in this process. With this study, the results of the TEXUS 45 flight were validated for another g-level (9x10-4g). In the course of the behavioural investigations we were able to show that most fish could adapt to these μg condition. Fish experiencing permanently 9x10-4g during the whole flight exhibit less kinetotic movements and from this we conclude, that they might use this minimal g-force for orientation. Furthermore these behavioural data were correlated with the morphology of otoliths (Lapilli and Sagittae).

  7. PALEOBATHYMETRIC INTERPRETATION OF THE FISH OTOLITHS FROM THE LOWER - MIDDLE QUATERNARY DEPOSITS OF KEPHALLONIA AND ZAKYNTHOS ISLANDS (IONIAN SEA, WESTERN GREECE

    Directory of Open Access Journals (Sweden)

    KONSTANTINA AGIADI

    2010-03-01

    Full Text Available Fish otoliths are herein used to estimate the depositional depth of the Early - Middle Pleistocene deposits at SE Zakynthos and SW Kephallonia Islands (Ionian Sea, Western Greece, through comparison with the modern bathymetric distributions of the identified fish taxa. These estimates provide a more detailed picture of the depth variations for the Gelasian - Ionian stage interval in the study areas. The Lower Pleistocene marine deposits of the Gerakas Formation (SE Zakynthos Island, Ionian Sea were deposited at average depths of 400-450 meters, with eustacy playing an important role in the depth variability, between 1.95-1.73 Ma. An uplifting episode, followed by subsidence takes place between 1.73-1.66 Ma, taking the area to 200-300 meters of depth, and then back to 400-500 meters. However, the area seems uplifted again to 200-400 meters later on in the Calabrian stage (1.25-0.97 Ma. Sedimentation of the Akrotiri deposits (NW Kephallonia Island, Ionian Sea, during the same chronostratigraphic interval, took place in a similar setting. At the Early Pleistocene (1.95-1.73 Ma this basin reached depths of 400-450 meters, with uplift and following subsidence taking place between 1.73-1.66 Ma. Overall, the application of fish otolith paleobathymetry in the study areas provide a detailed picture of the depth variations for the Early Quaternary interval and refine the currently hypothesized pattern of tectonic movements. 

  8. Otolith Trace Elemental Analyses of South American Austral Hake, Merluccius australis (Hutton, 1872) Indicates Complex Salinity Structuring on their Spawning/Larval Grounds

    Science.gov (United States)

    Brickle, Paul; Schuchert, Pia C.; Arkhipkin, Alexander I.; Reid, Malcolm R.; Randhawa, Haseeb S.

    2016-01-01

    Trace element signatures of otolith edges and cores from 335 austral hake (Merluccius autralis) were analysed using LA-ICPMS from samples collected in Chilean and Falkland Islands' waters, in order to provide potential insights into stock discrimination and migrations. Fish were caught in two locations in Chile and four locations in the south-west of the Falkland Islands Shelf. Univariate and multivariate analyses of trace element signatures in the edges of otoliths, representing adult fish, were not able to distinguish between samples collected in Chile and the Falkland Islands. Cluster analyses based on Ward’s similarity/distance metric suggested that it was possible to identify two groups from core signatures. Further analyses of this perceived clustering of the core concentrations revealed that this was largely due to the wide spread of Sr/Ca ratios in the otoliths’ cores. Gaussian finite mixtures using MCMC methods confirmed that Sr/Ca ratios form two separate distributions with significantly different mean values while concentrations of other elements showed no evidence of the presence of two or more distributions. The results suggest that there is only one spawning stock of austral hake with spawning situated in and around the Chilean fjords (43°30’S– 47°S) and the variation in Sr/Ca ratios likely suggests complex salinity structuring in this area. PMID:26727274

  9. Otolith asymmetry and kinetotic behaviour of fish at high-quality microgravity: A drop-tower experiment

    Science.gov (United States)

    Anken, R.; Forster, A.; Baur, U.; Feucht, I.; Hilbig, R.

    2006-01-01

    contrast to the results gained using PF specimens, according to which otolith asymmetry (differences in the size of the inner ear stones between the left and right side of the body) was significantly higher in kinetotic specimens as compared to normally swimming fish, asymmetry did not differ between the SM, LR and normally swimming drop-tower samples. This finding is discussed on the basis of the especially low gravity environment in the drop-tower experiment.

  10. Mutant Medaka fish having a deficiency in otolith-vestibular system and their behavior in microgravity.

    Science.gov (United States)

    Ijiri, K

    2000-07-01

    Vestibular and visual senses are two major factors fish use for controlling their posture under 1 G conditions. From various studies in the past (parabolic flights and some ground-laboratory experiments), I came to have a hypothesis that "heavily eye-dependent" fish are tolerant to microgravity (micro-G). Theoretically, for "heavily eye-dependent" fish, the following three types may exist. (a) Fish having good eyesight, and having an ordinary sensitivity to gravity, (b) Fish having an ordinary eyesight, and having less sensitivity to gravity, (c) Fish having good eyesight, and having less sensitivity to gravity. In Medaka fish (Oryzias latipes), these three types have successfully been obtained. In this paper, the behavior of such different types of Medaka fish under micro-G will be studied by use of parabolic flights of an airplane. The ground-laboratory experiments are also reported, which focus on the contribution of both vestibular and visual senses to the posture control for each of three types of Medaka fish. PMID:12697536

  11. Kinetotic behaviour and otolith asymmetry of fish under "low quality microgravity" - a drop-tower experiment at 0.03-0.05g

    Science.gov (United States)

    Anken, Ralf; Knie, Miriam; Hilbig, Reinhard; Anken, Ralf

    We have shown earlier that some fish of a given batch reveal motion sickness (a kinetosis) at the transition from earth gravity to diminished gravity. The percentual ratios of the various types of behaviour (normal swimming and kinetotic swimming; kinetotic specimens revealed looping responses/LR or spinning movements/SM), however, highly differed depending on the quality of diminished gravity. Whereas kinetoses were exhibited by some 90 In striking contrast to the results gained using PF specimens, according to which otolith asymmetry (differences in the size and calcium incorporation of the inner ear stones between the left and right side of the body) was significantly higher in kinetotic specimens as compared to normally swimming fish, a comparable asymmetry between kinetotically and normally swimming drop-tower samples (HQM) could statistically not be verified. The present study was designed to further elucidate the role of otolith asymmetry concerning an individually different susceptibility to kinetoses. In order to test, whether the differing results between the PF and the drop-tower experiment were based exclusively on the differing quality of diminished gravity, or, if further parameters of the PF and the drop-tower environment (e.g., vibrations and changing accelerations during PFs or the brisk compression of the drop-capsule at its release) need to be taken into consideration to explain the earlier results, drop-tower flights were performed at LQM. This simulation of PF "micro"gravity was carried out in housing larval cichlid fish (Oreochromis mossambicus) within a centrifuge at 0.03-0.05g during the drop-tower flights. The percentual ratios of the swimming behaviour at drop-tower LQM ranged between those of PF LQM and (drop-tower) HQM. This indicates that many normally swimming fish during PFs use cues other than the residual gravity (e.g., vibrations detected by the lateral line organ) for orientation. Furthermore, looping responses seem to be

  12. Otolith ocular reflex function of the tangential nucleus in teleost fish.

    Science.gov (United States)

    Suwa, H; Gilland, E; Baker, R

    1999-05-28

    In teleost fish, the tangential nucleus can be identified as a compact, separate cell group lying ventral to the VIIIth nerve near the middle of the vestibular complex. Morphological analysis of larval and adult hindbrains utilizing biocytin and fluorescent tracers showed the tangential nucleus to be located entirely within rhombomeric segment 5 with all axons projecting into the contralateral MLF. Combined single-cell electrophysiology and morphology in alert goldfish found three classes of neurons whose physiological sensitivity could be readily correlated with rotational axes about either the anterior (45 degrees), posterior (135 degrees), or horizontal (vertical axis) semicircular canals. Tangential neurons could be distinguised from those in semicircular-canal specific subnuclei by an irregular, spontaneous background of 10-15 sp/s and sustained static sensitivity after +/- 4 degrees head displacements. Each axis-specific tangential subtype terminated appropriately onto oculomotor subnuclei responsible for either vertical, torsional, or horizontal eye movements and, in a few cases, axon collaterals descended in the MLF toward the spinal cord. We hypothesize, therefore, that the tangential nucleus consists of 3 axis-specific phenotypes that process gravitoinertial signals largely responsible for controlling oculomotor function, but that also in part, maintain body posture. PMID:10409097

  13. Sagittal otolith morphology and daily increment analysis of Setipinna taty from L(u)si Fishing Ground%吕四渔场黄鲫耳石形态及日龄分析

    Institute of Scientific and Technical Information of China (English)

    张健; 刘必林; 陈小康; 彭永章

    2011-01-01

    根据2009年5月在吕四渔场单桩张网采集的231尾黄鲫幼鱼,对其耳石形态和储存信息进行分析.结果显示,耳石全长范围为1.88~4.91 mm,平均3.75mm;耳石重量范围为0.8~13.7 mg,平均6.4 mg.黄鲫耳石全长和叉长拟合生长方程为LOA=2.6322 ln(L)-8.2612.耳石全长与耳石重量关系式为WO=0.196×LOA-2.6186.黄鲫年龄范围为60~258 d,优势年龄组为90~150 d,占总体的69.5%;叉长与年龄拟合线性生长方程为L=0.2034 ×A+69.12.孵化日期为1月至3月,主要集中在2月份,占总体的83.6%.%231 Setipinna taty individuals were sampled by single-stake stownet fishery from Ltsi Fishing Ground in the south of the Yellow Sea to analyze sagittal otolith morphology and information contained. The results indicated that the otolith length ranged from 1.88 to 4.91 mm with mean of 3.75 mm and otolith weight ranged from 0.8 to 13.7 mg with mean of 6.4mg. Observation of the otoliths of Setipinna taty showed that the growth equation was fitted by the all otolith length (LoA, mm) and fork length as follows, LOA =2.6322 In(L) -8. 2612. The relationship between LoA and otolith weight (Wo, mg) was Wo =0. 196 ×OAL-2.6186. It is induced that the age range of the Setipinna taty individuals measured was 60 -258 days, in which 90 ~ 150 days dominated the age range, accounting for 69.5%. The linear growth equation between fork length and age (day) was L =0. 2034 ×A + 69.12. The estimated hatch dates of Setipinna taty in the south of the Yellow Sea were distributed between January and March and 83.6% concentrated in February.

  14. North Atlantic ecosystem shifts revealed by cod otolith δ15N and δ13C chronologies

    DEFF Research Database (Denmark)

    Pedersen, Jens Brøgger; Nielsen, Jens Munk; Steingrund, Petur;

    Changes in climate and exploitation have caused large fluctuations in the productivity of many North Atlantic cod populations and the collapse of many cod fisheries. These fluctuations are most likely due to a combined effect of physical processes and changes in ecosystem trophic structure. To...... study the link between environmental changes and ecosystem trophic structure we developed δ15N and δ13C chronologies by analyzing the organic matrix of cod otoliths from the Faroe Shelf cod population (1950-2010) and the Nuuk Fjord cod population (1927-2009). Significant correlations between δ15N & δ13C...... annual mean values over time were seen in both ecosystems, suggesting δ15N & δ13C values were affected by the same overall processes. There were significant effects of climate variables (temperature, Atlantic Multi-decadal Oscillation (AMO) and Sub Polar Gyre index) on δ15N and δ13C chronologies in both...

  15. Otolith growth of Springer's demoiselle, Chrysiptera springeri (Pomacentridae, Allen & Lubbock), on a protected and non-protected coral reef

    DEFF Research Database (Denmark)

    Retzel, A.; Hansen, A.D.; Grønkjær, P.

    2007-01-01

    The structural complexity of coral reefs is important for their function as shelter and feeding habitats for coral reef fishes, but physical disturbance by human activities often reduce complexity of the reefs by selectively destroying fragile and more complex coral species. The damselfish Springer......'s demoiselle Chrysiptera springeri primarily utilize complex coral heads for shelter and are hence vulnerable to human disturbance. In order to evaluate the potential effect of habitat degradation on juvenile fish growth, coral reef cover, fish age at settling and otolith growth, juvenile Springer's demoiselle...... was investigated on a protected and non-protected coral reef in Darvel Bay, Borneo. The protected reef had higher coverage of complex branching corals and exhibited a more complex 3-dimensional structure than the non-protected reef. Springer's demoiselle settled at the same age on non-protected and...

  16. A method for improving the efficiency of proton microprobe profiling of strontium in otoliths using a vacuum compatible NaI detector

    International Nuclear Information System (INIS)

    The precision of proton microprobe measurements of Sr in otoliths by proton induced X-ray emission (PIXE) has been improved significantly by use of a large area low resolution NaI(Tl) detector. This is achieved by scanning the sample simultaneously with a high resolution Si(Li) detector to measure the main constituent Ca and to confirm the absence of other elements in the counting window used by the large area detector. In our experimental setup the count rate for Sr was improved by a factor of 30. We took advantage of this to improve precision and achieve higher sample throughput in studies of diadromous fish, i.e. those whose life cycles may include both marine and freshwater stages

  17. What can otolith shape analysis tell us about population structure of the European sardine, Sardina pilchardus, from Atlantic and Mediterranean waters?

    Science.gov (United States)

    Jemaa, Sharif; Bacha, Mahmoud; Khalaf, Gaby; Dessailly, David; Rabhi, Khalef; Amara, Rachid

    2015-02-01

    The European sardine, Sardina pilchardus, exhibits a complex population structure, which has produced conflicting results in previous genetic studies. Despite its importance in the fisheries industry, stock delineation for management and conservation purposes is still a matter of debate throughout the distribution range of the species. This study examines whether otolith shapes are more efficient than genetic markers to detect population structure in pelagic species with large population sizes. Sardines were analyzed from 15 sampling localities in the Northeast Atlantic and Mediterranean Sea covering almost the whole distribution range of the species. A combination of otolith shape indices and elliptic Fourier descriptors was investigated by multivariate statistical procedures. Within the studied area, three distinct groups were identified with an overall correct classification of 77%. Group A: northern Mediterranean Sea and Gulf of Gabès; group B: Atlantic Morocco-south Alboran-Algero-provençal coasts; and group C: European Atlantic coast. The Almeria-Oran front and the Gibraltar strait are not an efficient barrier for sardine population separation as there seems to be exchanges between populations of the south-western Mediterranean Sea and those of the Moroccan Atlantic Ocean coast or Gulf of Cadiz. The results are discussed in relation to environmental conditions, oceanographic features, and physical barriers to dispersal in the study area, and compared with those obtained by previous genetic, morphometric, and meristic data. For pelagic species with high gene flow, present results highlighted the need to take into account the identification of phenotypic stocks to ensure sustainable fishery benefits and efficient conservation as they may have unique demographic properties and responses to exploitation.

  18. Analysis of biogenic carbonates by inductively coupled plasma-mass spectrometry (ICP-MS). Flow injection on-line solid-phase preconcentration for trace element determination in fish otoliths

    Energy Technology Data Exchange (ETDEWEB)

    Arslan, Z.; Paulson, A.J. [National Oceanic and Atmospheric Administration (NOAA), Northeast Fisheries Science Center (NFSC), James J. Howard Marine Sciences Laboratory, Highlands, NJ (United States)

    2002-04-01

    The aragonite deposits within the ear bones (otoliths) of teleost fish retain a chemical signal reflecting the life history of fish (similar to rings of trees) and the nature of fish habitats. Otoliths dissolved in acid solutions contain high concentrations of calcium and a variety of proteins. Elimination of matrix salts and organic interferences during preconcentration is essential for accurate determination of trace elements in otolith solutions by inductively coupled plasma-quadrupole mass spectrometry. An iminodiacetate-based chelating resin (Toyopearl AF-Chelate 650 M) has been used for on-line preconcentration and matrix separation for the determination of 31 transition and rare elements. Successful preconcentration of the elements was achieved at pH 5 by on-line buffering, except Mn which required pH 8.8. Sample solutions were loaded on to the column for 1 min at 3.2 mL min{sup -1}, and then eluted directly into the mass spectrometer with 4% v/v nitric acid. This procedure enabled up to 25-fold preconcentration with successful removal of the calcium matrix. The effect of heat-assisted oxidation with concentrated nitric acid was investigated to eliminate the organic matrix. It was found that heating to dryness after dissolution and further mineralization with the acid significantly improved the retention of the transition elements. The method was validated by analysis of a certified reference material produced from saggittal otoliths of emperor snapper (Lutjanus sebae), and then applied to the determination of trace metal concentrations in juvenile bluefin tuna (Thunnus thynnus) from the Western Pacific Ocean. (orig.)

  19. Using otoliths from a non-migratory fish (Slimy sculpin - Cottus cognatus) to evaluate temporal and spatial variability in 87Sr/86Sr ratios of river waters from a large and remote watershed in southwest AK, USA - the Nushagak River

    Science.gov (United States)

    Brennan, S.; Fernandez, D. P.; Zimmerman, C.; Cerling, T. E.; Wooller, M. J.

    2013-12-01

    Heterogeneity in 87Sr/86Sr ratios of river-dissolved strontium (Sr) across geologically diverse watersheds and landscapes is a useful tool for investigating provenance, connectivity and movement patterns of various materials and organisms. Evaluating temporal variation across watersheds at different spatial scales is expensive and difficult, especially in remote areas, but is necessary to accurately interpret Sr isotopic data. We used the time-keeping properties inherent to otoliths, the ever-growing aragonitic auditory structure of teleost fish, from non-migratory Slimy sculpin (Cottus cognatus) to evaluate seasonal and inter-annual temporal variability in 87Sr/86Sr ratios of river waters throughout a large watershed in remote Alaska, USA - the Nushagak River. Using laser ablation multi-collector inductively coupled plasma mass-spectrometry, 87Sr/86Sr ratios were measured from core to edge of otoliths from Slimy sculpin (n = 20) ranging in age from 3 to 6 years old captured at various sites within the Nushagak River watershed. Generalized additive models (GAMs) of 87Sr/86Sr profiles indicate that the majority of individuals (n = 14) exhibit no significant isotopic variation (p > 0.05) from core to edge of otoliths, though some did exhibit significant isotopic variation (n = 6, p << 0.05). In some instances, sculpin caught at the same site showed characteristically different 87Sr/86Sr profiles, which we interpret as variations in the micro-movements and life histories of these fish versus time-dependent changes in the 87Sr/86Sr ratio of water at a particular site. This study illustrates the use of otoliths from non-migratory fish to evaluate seasonal and inter-annual variability in 87Sr/86Sr ratios of river-dissolved Sr at multiple spatial scales within a watershed.

  20. Analysis of biogenic carbonates by inductively coupled plasma-mass spectrometry (ICP-MS). Flow injection on-line solid-phase preconcentration for trace element determination in fish otoliths.

    Science.gov (United States)

    Arslan, Z; Paulson, A J

    2002-04-01

    The aragonite deposits within the ear bones (otoliths) of teleost fish retain a chemical signal reflecting the life history of fish (similar to rings of trees) and the nature of fish habitats. Otoliths dissolved in acid solutions contain high concentrations of calcium and a variety of proteins. Elimination of matrix salts and organic interferences during preconcentration is essential for accurate determination of trace elements in otolith solutions by inductively coupled plasma-quadrupole mass spectrometry. An iminodiacetate-based chelating resin (Toyopearl AF-Chelate 650 M) has been used for on-line preconcentration and matrix separation for the determination of 31 transition and rare elements. Successful preconcentration of the elements was achieved at pH 5 by on-line buffering, except Mn which required pH 8.8. Sample solutions were loaded on to the column for 1 min at 3.2 mL min(-1), and then eluted directly into the mass spectrometer with 4% v/v nitric acid. This procedure enabled up to 25-fold preconcentration with successful removal of the calcium matrix. The effect of heat-assisted oxidation with concentrated nitric acid was investigated to eliminate the organic matrix. It was found that heating to dryness after dissolution and further mineralization with the acid significantly improved the retention of the transition elements. The method was validated by analysis of a certified reference material produced from saggittal otoliths of emperor snapper ( Lutjanus sebae), and then applied to the determination of trace metal concentrations in juvenile bluefin tuna ( Thunnus thynnus) from the Western Pacific Ocean. PMID:12012188

  1. Estimating the proportion of river and sea spawning whitefish in catches from the brackish Gulf of Bothnia (Baltic Sea by gill raker counting, genotyping and otolith chemistry analysis

    Directory of Open Access Journals (Sweden)

    Henry Hägerstrand

    2015-11-01

    Full Text Available European whitefish (Coregonus lavaretus is a commercially and recreationally important species in the Gulf of Bothnia (Figure 1, where the salinity of the surface water increases from ~2 ‰ to ~6 ‰ in the north-south (~725 km direction. Two sympatric ecotypes with similar outer features occur: stationary sea spawning whitefish and migrating anadromous river spawning whitefish (Lehtonen 1981. The two types mix in sea away from breeding locations and off breeding time. River spawning whitefish can undertake long feeding and spawning migrations, e.g. between the north and the south of the gulf. The river spawning whitefish abundantly occur at feeding grounds in the south where they stay for years, until maturing. Mainly due to anthropogenic destruction of the spawning rivers, the river spawning whitefish has diminished during last decades and is presently listed among endangered species (Helcom 2013. A reliable assessment of the two ecotypes and their subpopulations is a prerequisite for taking effective actions for stock preservation. In order to compare methods for whitefish ecotype identification we undertook genotyping, otolith chemistry analysis and gill raker counting on river and sea spawning whitefish populations. Materials and methods. Whitefish to undergo spawning was sampled from rivers along the Finnish west coast (river spawners and at sea from known spawning sites close to the southern feeding grounds at the Åland Islands and the Archipelago Sea (sea spawners (Himberg et al. 2015, Figure 1. Gill rakers were counted on the left outer arch. Data on gill raker number was also collected from literature. Genetic diversity was assessed by nine microsatellite markers (Ozerov et al. 2015. Two methods were used for otolith (sagittae chemistry analysis. Otoliths were dissolved and analyzed for elemental concentrations with ICP-OES (Hägerstrand et al. 2015, or polished to the core and analyzed for core strontium concentration by PIXE

  2. Age estimations of wild pallid sturgeon (Scaphirhynchus albus, Forbes & Richardson 1905) based on pectoral fin spines, otoliths and bomb radiocarbon: inferences on recruitment in the dam-fragmented Missouri River

    Science.gov (United States)

    Braaten, P. J.; Campana, S. E.; Fuller, D. B.; Lott, R. D.; Bruch, R. M.; Jordan, G. R.

    2015-01-01

    An extant stock of wild pallid sturgeon Scaphirhynchus albus persists in the fragmented upper Missouri River basin of Montana and North Dakota. Although successful spawning and hatch of embryos has been verified, long-term catch records suggest that recruitment has not occurred for several decades as the extant stock lacks juvenile size classes and is comprised exclusively of large, presumably old individuals. Ages of 11 deceased (death years 1997–2007) wild S. albus (136–166 cm fork length) were estimated based on pectoral fin spines, sagittal otoliths and bomb radiocarbon (14C) assays of otoliths to test the hypothesis that members of this stock are old and to provide inferences on recruitment years that produced the extant stock. Age estimations based on counts of presumed annuli were about 2 years greater for otoliths (mean = 51 years, range = 43–57 years) than spines (mean = 49 years, range = 37–59 years). Based on 14C assays, confirmed birth years for all individuals occurred prior to 1957, thus establishing known longevity of at least 50 years. Estimated age based on presumed otolith annuli for one S. albus was validated to at least age 49. Although 14C assays confirmed pre-1957 birth years for all S. albus, only 56% of estimated ages from spines and 91% of estimated ages from otoliths depicted pre-1957 birth years. Both ageing structures were subject to under-ageing error (up to 15 years). Lack of or severe curtailment of S. albus recruitment in the upper Missouri River basin since the mid-1950s closely parallels the 1953–1957 timeframe when a mainstem reservoir was constructed and started to fill. This reservoir may function as a system-wide stressor to diminish recruitment success of S. albus in the upper Missouri River basin.

  3. Controlling

    OpenAIRE

    Lohnická, Jitka

    2009-01-01

    This thesis deals with the description and analysis of controlling methods in one unnamed company, which is the subsidiary of multinational corporation. Controlling, its function, objectives and controlling methods are theoretically defined in the thesis. The practical part of the thesis is focused on methods of planning in the company, its system of calculations, responsibility centres and reporting.

  4. Stable isotope compositions (O-C) of reef fish otoliths from the Taiaro lagoon (Tuamotu, French Polynesia): isotopic and biologic implications; Composition isotopique {delta}{sup 18}O-{delta}{sup 13}C des otolithes des populations de poissons recifaux de Taiaro (Tuamotu, Polynesie francaise): implications isotopiques et biologiques

    Energy Technology Data Exchange (ETDEWEB)

    Blamart, D.; Juillet-Leclerc, A.; Ouahdi, R. [Centre National de la Recherche Scientifique (CEA-CNRS), Lab. des Sciences du Climat et de l' Environnement, 91 - Gif-sur-Yvette (France); Escoubeyrou, K.; Lecomte-Finiger, R. [Universite de Perpignan, Lab. d' Ichtyoecologie Tropicale et Mediterraneenne, ESA 8046 CNRS-EPHE, 66 - Perpignan (France)

    2002-02-01

    Nuclei (larval stage) and outer parts (adult stage) of fish otoliths from the Taiaro closed lagoon (French Polynesia) and adjacent ocean have been analysed for the C-O isotopic compositions. {delta}{sup 18}O values of the nuclei of both populations indicate that isotopic equilibrium is reached. This implies that the lagoonal fish population has done its complete biological cycle in the lagoon and represents an adaptation in a closed system. {delta}{sup 18}O values of the outer parts show a slight isotopic disequilibrium (< 0.2%0) interpreted in term of vital effect. All the {delta}{sup 13}C values exhibit a strong isotopic disequilibrium related to metabolic activity. (authors)

  5. Residence time and drift patterns of larval June sucker Chasmistes liorus in the lower Provo River as determined by otolith microstructure.

    Science.gov (United States)

    Ellsworth, C M; Belk, M C; Keleher, C J

    2010-08-01

    Estimates of age derived from daily ring counts from otoliths and capture rates of larval June sucker Chasmistes liorus were used to determine the relationship between discharge rates of the Provo River and residence time and patterns of larval drift. During 1997, larval drift occurred over a 22 day period when discharge rates were low (mean +/-s.d. 3.2 +/- 0.0 m(3) s(-1)). In 1998, larval drift occurred in two separate events over a 40 day period. Discharge was higher during the first larval drift period (19 days; 24.8 +/- 1.3 m(3) s(-1)) and lower during the second larval drift period (17 days; 7.0 +/- 0.9 m(3) s(-1)). In 1997, no larval fish were collected at the lowermost transect on the Provo River (nearest Utah Lake), and few larvae >21 days of age were found. During the first drift period of 1998, larval C. liorus were collected at all transects, and mean age of larvae collected between upstream and downstream transects increased by c. 7 days. During the second drift period of 1998, only a few were collected in the lowermost transects, and age did not increase with proximity to the lake. Patterns in catch and age distribution of larval C. liorus in the lower Provo River suggest that recruitment failure occurs during the larval drift period in years with insufficient discharge to transport larvae into the lake. PMID:20701638

  6. New insights about the population structure of the blue jack mackerel (Trachurus picturatus in the NE Atlantic using otolith stable isotope ratios

    Directory of Open Access Journals (Sweden)

    Cláudia Moreira

    2015-11-01

    Full Text Available The blue jack mackerel Trachurus picturatus is a pelagic fish widely distributed in the NE Atlantic and also found in the Mediterranean and Black Seas. It is an economically important resource in the Macaronesian islands of Azores, Madeira and Canaries, but despite its fishery value and ecological importance, fluctuations in the landings are difficult to explain since studies regarding the population dynamics, stocks structure, fish movements and habitat connectivity are inexistent. The populations of marine pelagic fishes, in particular the migratory ones, such as T. picturatus,, may be erroneously considered an homogenous population unit because they show broad geographic distributions, large population sizes and high migratory movements. Stable isotope ratios, namely δ18O and δ13C, measured by standard mass spectrometric techniques in whole otolith samples of T. picturatus adults sampled in the fishery grounds of the Islands of Azores, Madeira and Canaries, and at the Portuguese mainland (Matosinhos, Peniche and Portimão during the spring-summer of 2013 were analysed. The 18O signatures followed the general tendency taking into account the seawater temperatures of the sampling regions. 13C signatures showed however differences between the oceanic or continental origin of the fish. Both variables provided location-specific signatures. Further studies including mitochondrial and nuclear DNA studies are also been conducted to acquire new knowledge for fisheries conservation purposes.

  7. A review of early gadiform evolution and diversification: first record of a rattail fish skull (Gadiformes, Macrouridae) from the Eocene of Antarctica, with otoliths preserved in situ

    Science.gov (United States)

    Kriwet, Jürgen; Hecht, Thomas

    2008-10-01

    Codfishes, the Gadiformes, are quite abundant in modern temperate and polar waters with a fossil record ranging back into the Palaeogene. The oldest records are from the Danian and Selandian of Europe and South Australia. The bipolar distribution early in their evolutionary history implies that their origin must have occurred quite early in the Palaeocene, or even in the Late Cretaceous with subsequent rapid diversification. By the Eocene, gadiforms were highly abundant and widespread. With the exception of gadiforms, no Eocene Antarctic teleostean group is present in the modern Antarctic fauna. Here, we review the early evolution and diversification of gadiforms in general and of macrouroids in particular. We also describe the undoubtedly oldest skeletal macrourid specimen with otoliths preserved in situ. It is the first definitive record of this group from the Eocene of Antarctica filling a gap in its stratigraphic distribution. The fossil record of gadiforms in general and macrouroids in particular indicates that the origin of both was in shallow shelf environments but with adaptations to deep-water settings early in their evolution. While gadoids seemingly originated in the earliest Palaeogene and rapidly experienced a first major radiation event in the eastern North Atlantic and/or North Sea Basin, macrouroids evolved in the Southern Ocean and migrated northwards into the South Atlantic before the establishment of the circum-Antarctic current and subsequent isolation of the Antarctic fish fauna. These two timely and regional separated adaptive radiation events in the Palaeogene gave rise to their modern taxonomic diversity and global distribution.

  8. Calbindin and parvalbumin are early markers of non-mitotically regenerating hair cells in the bullfrog vestibular otolith organs

    Science.gov (United States)

    Steyger, P. S.; Burton, M.; Hawkins, J. R.; Schuff, N. R.; Baird, R. A.

    1997-01-01

    Earlier studies have demonstrated hair cell regeneration in the absence of cell proliferation, and suggested that supporting cells could phenotypically convert into hair cells following hair cell loss. Because calcium-binding proteins are involved in gene up-regulation, cell growth, and cell differentiation, we wished to determine if these proteins were up-regulated in scar formations and regenerating hair cells following gentamicin treatment. Calbindin and parvalbumin immunolabeling was examined in control or gentamicin-treated (GT) bullfrog saccular and utricular explants cultured for 3 days in amphibian culture medium or amphibian culture medium supplemented with aphidicolin, a blocker of nuclear DNA replication in eukaryotic cells. In control cultures, calbindin and parvalbumin immunolabeled the hair bundles and, less intensely, the cell bodies of mature hair cells. In GT or mitotically-blocked GT (MBGT) cultures, calbindin and parvalbumin immunolabeling was also seen in the hair bundles, cuticular plates, and cell bodies of hair cells with immature hair bundles. Thus, these antigens were useful markers for both normal and regenerating hair cells. Supporting cell immunolabeling was not seen in control cultures nor in the majority of supporting cells in GT cultures. In MBGT cultures, calbindin and parvalbumin immunolabeling was up-regulated in the cytosol of single supporting cells participating in scar formations and in supporting cells with hair cell-like characteristics. These data provide further evidence that non-mitotic hair cell regeneration in cultures can be accomplished by the conversion of supporting cells into hair cells.

  9. Patterns of primary growth increments in otoliths of Sparus aurata larvae in relation to water temperature and food consumption

    OpenAIRE

    Morales-nin, B; Gutiérrez Merino, Emilia; Massutí, Sofia

    1995-01-01

    Sparus aurata larvae reared under controlled water-temperature conditions during the first 24 days after hatching displayed a linear relationship between age (t) and standard length (SL): SL = 2.68 + 0.19 t (r2 = 0.91l). Increments were laid down in the sagittae with daily periodicity starting on day of hatching. Standard length (SL) and sagittae radius (OR) were correlated: SL(mm) = 2.65 + 0.012 OR(mm). The series of measurements of daily growth increment widths (DWI), food density and water...

  10. Comparison of growth rates estimated by otolith reading of Scorpaena porcus and Scorpaena notata caught on artificial and natural reefs of the northern Adriatic sea

    Directory of Open Access Journals (Sweden)

    Giuseppe Scarcella

    2011-01-01

    Full Text Available Despite the high number of studies on fish assemblages associated with artificial reefs and offshore platforms, little information exists on the growth rates of fish living on artificial and natural substrates. Age and growth was determined throughout otolith reading on two commercial scorpionfishes (Scorpaena porcus and Scorpaena notata caught in the surroundings of artificial structures (artificial reefs and gas platforms and natural habitats. Von Bertalanffy growth parameters were calculated for each species separately for each site. Age of S. porcus and S. notata ranged from 0 to 8 years and from 0 to 16 years, respectively. Kimura test applied to Von Bertalanffy growth curves indicated that the individuals of both species inhabiting the artificial structures had higher growth parameters than those caught in the natural habitat. The presence of artificial habitats in the northern Adriatic Sea positively affects growth rates and growth performance of both species, likely for the greater prey availability in respect to the natural open sea.Apesar do elevado número de estudos sobre as assembléias de peixes associadas a recifes artificiais e plataformas offshore, existe pouca informação sobre as taxas de crescimento dos peixes que vivem em substratos artificiais e naturais. A idade e crescimento foram determinados pela leitura de otólitos em dois peixes escorpião comerciais (Scorpaena porcus e Scorpaena notata capturados nas imediações de estruturas artificiais (recifes artificiais e plataformas de gás e habitats naturais. Parâmetros de crescimento de von Bertalanffy foram calculadoss separadamente para cada espécie e cada local. A idade de Scorpaena porcus e Scorpaena notata variou entre 0 e 8 anos e 0 e 16 anos, respectivamente. O teste Kimura aplicado às curvas de crescimento de Bertalanffy indicaram que os indivíduos das duas espécies que habitam as estruturas artificiais tinham parâmetros de crescimento mais elevados do que

  11. Ion microprobe Sr isotope analysis of carbonates with about 5 μm spatial resolution: An example from an ayu otolith

    International Nuclear Information System (INIS)

    A high lateral resolution secondary ion mass spectrometer (NanoSIMS NS50 ion microprobe) has been used to measure 87Sr/86Sr ratios in natural CaCO3 samples. A ∼2 nA O- primary beam was used to sputter a 5-7-μm diameter crater on the sample surface and secondary positive ions were extracted for mass analysis using an accelerating voltage of 8 kV and a Mattauch-Herzog geometry. The multi-collector system was adjusted to detect 43Ca+ (by a detector EM2), 80Ca2+ (EM3), 86Sr+ (EM4), and 87Sr+ (EM4b) ions at the same time. Then the magnetic field was scanned for the EM4 to detect 85Rb+, 86Sr+ and 87Sr+, while the EM4b can measure 86Sr+, 87Sr+ and 88Sr+, respectively. A mass resolution of 3600 at 10% peak height was attained with a flat peak top, while the sensitivity of Sr was about 10 cps/nA/ppm. An aragonite sample (coral skeleton standard; JCp-1) was used as a reference for Sr isotope ratio calibration. Repeated analyses of the JCp-1 show that the 87Sr/86Sr ratio agrees well with the seawater signature within a precision of 0.3 per mille at 2σ, after the series of corrections such as the Ca dimer, 87Rb, and a mass bias estimated by the 88Sr/86Sr ratio. The method was applied to an otolith (ear-stone) from ayu (Plecoglossus altivelis altivelis) collected from the Yodo river, Japan. Although experimental errors are relatively large, up to 3 per mille at 2σ, the ratios of the core region are higher than the seawater signature while more distal values agree well with seawater. The very outermost part again shows the relatively higher 87Sr/86Sr ratios. The spatial variation of 87Sr/86Sr ratios was consistent with amphidromous migration of the fish, namely, born in the lake and grown in the coastal sea and finally collected in a river

  12. MULTIELEMENT SOLID PHASE PRECONCENTRATION USING A CHELATING RESIN OF STYRENE DIVINYLBENZENE COPOLYMER AND APPLICATION TO ANALYSIS OF SEAWATER AND FISH OTOLITHS BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (ICP�MS).

    Science.gov (United States)

    Zereen, Fahmida; Yilmaz, Vedat; Arslan, Zikri

    2014-01-01

    A new chelating resin has been synthesized by immobilizing 4-(2-thiazolylazo) resorcinol (TAR) onto styrene divinlybenzene copolymer and examined for on-line solid phase extraction/preconcentration of Cd, Co, Cu, Ni, Pb and Zn in seawater and fish otoliths for determination by inductively plasma mass spectrometry (ICP-MS). A volume of 5.0 mL sample solution was loaded onto the mini column of TAR immobilized resin at 2.0 mL min(-1) via a sequential injection system. The optimum pH for multielement preconcentration was around pH 5.5. Recoveries were better than 96% in artificial seawater. Elution was achieved with 1.0 mL of 0.75 mol L(-1) HNO3. The resin possesses large sorption capacity ranging from 82.0 µmol g(-1) for Pb to 319 µmol g(-1) for Cu. The detection limits (3s) varied between 0.0016 µg L(-1) (Cd) and to 0.015 µg L(-1) (Zn) for preconcentration of 5.0 mL blank solutions (pH 5.5). Relative standard deviation (RSD)for three replicate runs was between 0.3% (Cd) and 6% (Zn) at 1.0 µg L(-1) level. The procedure was validated by analysis of Nearshore Seawater certified reference material (CASS-4), and then successfully applied to the determination of the trace elements in fish otoliths (CRM 22) and in coastal seawater and estuarine water samples. PMID:24976635

  13. 湘江鳡仔稚鱼个体和耳石生长发育研究%SOMATIC AND LAPILLUS OTOLITH ONTOGENETIC GROWTH AND DEVELOPMENT IN LARVAL AND JUVENILE ELOPICHTHYS BAMBUSA RICHARDSON IN THE XIANG RIVER

    Institute of Scientific and Technical Information of China (English)

    向建国; 向劲; 王星璐; 李钟杰; 谢松光

    2011-01-01

    E. Bambusa was collected in the Xiang River from June to July, 2008. Otolith analysis revealed that age of the specimens ranged from 4-25 days, and the back-calculated hatching dates were during May 27th to June 22nd. The mid-age of stage transition from preflexion to flexion was at the 6th day; from flexion to postflexion was at the 10th day; from postflexion to juvenile was at the 15.5th day. Piecewise regression revealed a knot in the growth functions of either body length or otolith radius, were both at the early postflexion stage (the 12nd-13rd day): the growth rate after the knot was 5 times and twice of that before the knot for body length and otolith radius respectively. The shape of lapillus was round in the preflexion stage; in the flexion stage, the anterior-posterior axis growth significantly exceeded along the dorsal-ventral axis, and the shape became oval; the otolith further elongated in the postflexion stage, and the peak of the posterior emerged to shape the whole lapillus pear; in the juvenile stage, the peak smoothed and the shape was mussel. Otolith shape and microstructural analyses can provide essential information revealing the critical events in the early life history of £. Bambusa.

  14. Momento de formación y periodicidad de los microincrementos de crecimiento en otolitos de larvas de pejerrey (Austromenidia regia mantenidas en laboratorio Formation moment and periodicity of the growth microincrements in the otoliths of pejerrey larvae (Austromenidia regia maintained in the laboratory

    Directory of Open Access Journals (Sweden)

    Jessica Peñailillo P.

    1996-01-01

    Full Text Available Larvas de pejerrey (Austromenidia regia se mantuvieron en laboratorio, por un período de 26 días, con el objeto de conocer la periodicidad y el momento de formación del primer microincremento de crecimiento en el otolito sagitta. La temperatura y el fotoperíodo se mantuvieron constantes. Las larvas se alimentaron ad libitum con plancton, alimento artificial y nauplios de Artemia sp. Se sacrificaron 5 larvas a intervalos regulares, a las que se les midió la longitud estándar y extrajeron los otolitos sagittae. Los otolitos fueron leídos por dos lectores, dos veces cada uno; las lecturas con más de tres microincrementos de diferencia se descartaron. Al eclosionar las larvas presentan una longitud estándar promedio de 7,3 mm, alcanzando al final del período experimental un promedio de 12,3 mm. El análisis de regresión entre el número de microincrementos y la edad en días entrega los siguientes parámetros: a = 5,86 y b = 0,98, resultando la pendiente significativamente igual a uno. El intercepto de la regresión indica que las larvas eclosionan con aproximadamente 6 microincrementos, lo cual se corroboró con el análisis de otolitos de larvas recién eclosionadas.In order to know the periodicity and the moment of first growth microincrement formation in the sagitta otolith of pejerrey larvae (Austromenidia regia were maintained in the laboratory for 26 days. The photoperiod and temperature were maintained constant. Larvae were fed ad libitum with plankton, artificial food for fishes and Artemia sp. nauplii. Five larvae were sacrificed at regular intervals; it standard length was measured then the sagittae and lapillus otoliths were extracted. The otoliths were reading by two readers counting twice each one, with more than three microincrements of diference in the reading were discarded. At larvae hatch present an average standard length of 7,3 mm, reaching an average standard length of 12,3 mm at the final of the experimental period

  15. Role of vestibular sensor on body sway control: coherence between head acceleration and stabilogram.

    Science.gov (United States)

    Teixeira, Felipe G; Jesus, Igor R T; Mello, Roger G T; Nadal, Jurandir

    2012-01-01

    This work aims at evaluating the role of the vestibular system in the postural sway control using the coherence function. A sample of 19 young, healthy male adults was monitored with a three axial accelerometer placed over the head during a stabilometric test, standing on a force platform during 3 min in four conditions: eyes closed and open, and feet apart and together. The magnitude squared coherence (MSC) function and Monte Carlo simulation was used to correlate changes in body sway with head accelerations. Significant MSC values were found in the frequency range 0.1-0.5 Hz, mainly in conditions of larger oscillations: eyes closed and feet together. These results may be related to utricular otoliths responses and ankle strategy. PMID:23367028

  16. Existence of anadromous Coilia nasus in Xinjiang River of Jiangxi Province as determined by otolith microchemistry%信江发现溯河洄游型刀鲚的实证研究

    Institute of Scientific and Technical Information of China (English)

    卢明杰; 姜涛; 刘洪波; 陈婷婷; 杨健

    2015-01-01

    利用电子探针微区分析技术,对2014年8月1日采自江西省余干县瑞洪镇信江(鄱阳湖水系五大河流之一)江段的刀鲚(Coilia nasus)的矢耳石进行了锶和钙的微化学分析研究。元素定量线分析表明,样品的锶钙比值(Sr/Ca×103)波动显著,不仅具有对应淡水生活的低值(Sr/Ca×103<3),而且出现了对应于海水生活的高值(3otoliths of C. nasus collected from the Ruihong section of the Xinjiang River (the most distant branch of Poyang Lake, ~1000 km from the Yangtze River estuary) near Yugan County in Jiangxi Province. Line transect results clearly showed a complex Sr/Ca ratio (i.e., Sr/Ca×103) pattern, including low-ratio freshwater habitat (Sr/Ca×103<3) and high-ratio seawater habitat (3

  17. Cardiovascular and Postural Control Interactions during Hypergravity: Effects on Cerebral Autoregulation in Males and Females

    Science.gov (United States)

    Goswami, Nandu; Blaber, Andrew; Bareille, Marie-Pierre; Beck, Arnaud; Avan, Paul; Bruner, Michelle; Hinghofer-Szalkay, Helmut

    2012-07-01

    Orthostatic intolerance remains a problem upon return to Earth from the microgravity environment of spaceflight. A variety of conditions including hypovolemia, cerebral vasoconstriction, cerebral or peripheral vascular disease, or cardiac arrhythmias may result in syncope if the person remains upright. Current research indicates that there is a greater dependence on visual and somatosensory information at the beginning of space flight with a decreased otolith gain during prolonged space flight (Herault et al., 2002). The goal of the research is to further our understanding of the fundamental adaptive homeostatic mechanisms involved in gravity related changes in cardiovascular and postural function. Cardiovascular, cerebrovascular, and postural sensory motor control systems in male and female participants before, during, and after exposure to graded levels of hyper-G were investigated. Hypotheses: 1) Activation of skeletal muscle pump will be directly related to the degree of orthostatic stress. 2) Simultaneous measurement of heart rate, blood pressure and postural sway will predict cardio-postural stability. Blood pressure and heart rate (means and variability), postural sway, center of pressure (COP), baroreflex function, calf blood flow, middle cerebral artery blood flow, non-invasive intracranial pressure measurements, and two-breath CO2 were measured. Results from the study will be used to provide an integrated insight into mechanisms of cardio-postural control and cerebral autoregulation, which are important aspects of human health in flights to Moon, Mars and distant planets.

  18. 基于地标点几何形态测量法识别北部湾4种白姑鱼矢耳石形态%Using landmark-based geometric morphometrics analysis to identify sagittal otolith of four Pennahia fish species

    Institute of Scientific and Technical Information of China (English)

    侯刚; 刘丹丹; 冯波; 卢伙胜

    2013-01-01

    We investigated the identification in sagittal otoliths using landmark-based geometric morphometrics method among four sympatric species of the genus Pennahia: truncatetail white croaker P.anea (n=49), bighead white croaker P.macrocephalus (n=50), pawak croaker P. pawak (n=49) and white croaker P.argentata (n=29).The specimens were collected off Beibu Gulf from April 2010 to October 2010. Landmark coordinate values were extracted after otolith digitized by image processing and processed by relative warp principal component (RW), thin plate spline analysis and grad distortion. The 12 RW were then identified using discrimination analysis to differentiate the otoliths of four Pennahia species. The result indicated that, the 1st, 2nd and 3rd RW accounted for 46.57%, 25.39% and 10.02% of the total variation respectively, of which TypeⅠlandmarks 6 and 7, TypeⅡlandmarks 5 and 8 had important contributions, and could explain the most variation. The most morphological variation were displayed in neck, head width pole, and tail of tadpole-shaped sulcus. The gradual discrimination analysis and cross validation indicated that P.anea, P.macrocephalus and P. pawak got average exactitude distinguish ratios of 81.6%~100%, while P.argentata 58.6%, indicating that it contained a potential risk by using the morphology of tadpole-shaped impression owned by Sciaenidae to discriminate the four congeneric Pennahia species. It is necessary to notice this problem in the related otolith morphology research and application in feeding ecology.%利用2010年4月至2010年10月采自北部湾海域的49尾截尾白姑鱼(Pennahia anea)、50尾大头白姑鱼(P. macrocephalus)、49尾斑鳍白姑鱼(P. pawak )和29尾白姑鱼(P.argentata)矢耳石样本,运用基于地标点法的几何形态测量学方法研究了4种鱼类矢耳石形态识别问题。耳石经图像处理后提取地标点坐标值,进行相对扭曲主成分分析,通过判别分析来区分4种白姑鱼的耳石,

  19. Otolith output - Project to study alternative life history types of fall Chinook based on otoliths

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The life-history complexity of Snake River fall Chinook salmon has hindered efforts to manage the ESU. In particular, the existence of an overwintering behavior in...

  20. Controllable circuit

    DEFF Research Database (Denmark)

    2010-01-01

    A switch-mode power circuit comprises a controllable element and a control unit. The controllable element is configured to control a current in response to a control signal supplied to the controllable element. The control unit is connected to the controllable element and provides the control...

  1. Sensory Interactions for Head and Trunk Control in Space in Young and Older Adults During Normal and Narrow-Base Walking.

    Science.gov (United States)

    Zhang, Fang; Deshpande, Nandini

    2016-01-01

    Fifteen young (20-30 years old) and 15 older (>65 years old) healthy participants were recruited to investigate age-related differences in head and trunk control under suboptimal vestibular conditions (galvanic vestibular stimulation, or GVS) and vision conditions during normal and narrow-based walking. Head-roll velocity decreased in the blurred-vision condition and marginally increased with GVS in older but not in young participants. Head pitch increased, whereas head-roll velocity decreased in narrow-base walking. Trunk pitch, trunk-pitch velocity, and gait speed increased with GVS, whereas trunk-pitch velocity and gait speed decreased in narrow-base walking. Marginally increased head-roll velocity in the older participants possibly suggests decreased integrative ability of the central nervous system in elderly people. The changes in head control during narrow-base walking may be an attempt to simplify the interpretation of the vestibular signal and increase otolith sensitivity. The complexity of controlling the trunk in the mediolateral direction was suggested by different strategies used for trunk control in different conditions. PMID:25675141

  2. Dream controller

    Science.gov (United States)

    Cheng, George Shu-Xing; Mulkey, Steven L; Wang, Qiang; Chow, Andrew J

    2013-11-26

    A method and apparatus for intelligently controlling continuous process variables. A Dream Controller comprises an Intelligent Engine mechanism and a number of Model-Free Adaptive (MFA) controllers, each of which is suitable to control a process with specific behaviors. The Intelligent Engine can automatically select the appropriate MFA controller and its parameters so that the Dream Controller can be easily used by people with limited control experience and those who do not have the time to commission, tune, and maintain automatic controllers.

  3. Controllable dose; Dosis controlable

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Anaya M, R.A. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: jtar@nuclear.inin.mx

    2004-07-01

    With the purpose of eliminating the controversy about the lineal hypothesis without threshold which found the systems of dose limitation of the recommendations of ICRP 26 and 60, at the end of last decade R. Clarke president of the ICRP proposed the concept of Controllable Dose: as the dose or dose sum that an individual receives from a particular source which can be reasonably controllable by means of any means; said concept proposes a change in the philosophy of the radiological protection of its concern by social approaches to an individual focus. In this work a panorama of the foundations is presented, convenient and inconveniences that this proposal has loosened in the international community of the radiological protection, with the purpose of to familiarize to our Mexican community in radiological protection with these new concepts. (Author)

  4. Birth Control

    Science.gov (United States)

    Birth control, also known as contraception, is designed to prevent pregnancy. Birth control methods may work in a number of different ... eggs that could be fertilized. Types include birth control pills, patches, shots, vaginal rings, and emergency contraceptive ...

  5. Optimal control subsumes harmonic control

    OpenAIRE

    Boumaza, Amine; Scherrer, Bruno

    2007-01-01

    We consider trajectory planning within the frameworks of optimal control and harmonic control. We present a formal evidence, in continuous domain and in a standard discretization, that harmonic control is the limit case of a some optimal control problem in which we make the noise level tend to infinity. In other words we show that optimal control subsumes harmonic control. We discuss properties of both paradigms and present simulations that illustrate this relationship.

  6. Losing control

    DEFF Research Database (Denmark)

    Leppink, Eric; Odlaug, Brian Lawrence; Lust, Katherine;

    2014-01-01

    picking disorder). CONCLUSIONS: Assaultive behavior appears fairly common among college students and is associated with symptoms of depression and impulse control disorders. Significant distress and diminished behavioral control suggest that assaultive behaviors may often be associated with significant...

  7. Weight Control

    Science.gov (United States)

    ... obese. Achieving a healthy weight can help you control your cholesterol, blood pressure and blood sugar. It ... use more calories than you eat. A weight-control strategy might include Choosing low-fat, low-calorie ...

  8. Associational control

    DEFF Research Database (Denmark)

    Hvid, Helge Søndergaard; Lund, Henrik Lambrecht; Grosen, Sidsel Lond;

    2010-01-01

    Over the last 30 years, the concept of control has had a central position in research into the psychological working environment. Control has been understood as individual autonomy and individual opportunities for development. This article examines whether the concept of control has the same key ...... critical potential. This conclusion is supported by case studies of four Danish banks....

  9. Neurofuzzy Control

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1997-01-01

    These notes are for a course in fuzzy control and neural networks. By neural networks we more precisely mean neurofuzzy systems rather than pure neural network theory. The notes are an extension to the existing notes on fuzzy control (Jantzen, Fuzzy Control, 1994)....

  10. Controlling friction

    OpenAIRE

    Elmer, Franz-Josef

    1997-01-01

    Two different controlling methods are proposed to stabilize unstable continuous-sliding states of a dry-friction oscillator. Both methods are based on a delayed-feedback mechanism well-known for stabilizing periodic orbits in deterministic chaos. The feedback variable is the elastic deformation. The control parameter is either the sliding velocity or the normal force. We calculate analytically stability boundaries in the space of control parameter and delay time. Furthermore, we show that our...

  11. Nuclear control

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Wan Kee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    International cooperation in nuclear industries requires nuclear control as prerequisites. The concept of nuclear control is based on the Treaty on the Non-proliferation of Nuclear Weapon (NPT). The International Atomic Energy Agency (IAEA) plays central role in implementing nuclear control. Nuclear control consists of nuclear safeguards, physical protection, and export/import control. Each member state of NPT is subject to the IAEA`s safeguards by concluding safeguards agreements with the IAEA. IAEA recommends member states to implement physical protection on nuclear materials by `The Physical Protection of Nuclear Material` and `The Convention on the Physical Protection of Nuclear Material` of IAEA. Export/Import Control is to deter development of nuclear weapons by controlling international trade on nuclear materials, nuclear equipments and technology. Current status of domestic and foreign nuclear control implementation including recent induction of national inspection system in Korea is described and functions of recently set-up Technology Center for Nuclear Control (TCNC) under the Korea Atomic Energy Research Institute (KAERI) are also explained. 6 tabs., 11 refs. (Author).

  12. Taking Control

    Centers for Disease Control (CDC) Podcasts

    2007-11-01

    This podcast gives action steps and reasons to control diabetes.  Created: 11/1/2007 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 11/2/2007.

  13. optimal control

    Directory of Open Access Journals (Sweden)

    L. I. Rozonoer

    1999-01-01

    Full Text Available Necessary and sufficient conditions for existence of optimal control for all initial data are proved for LQ-optimization problem. If these conditions are fulfilled, necessary and sufficient conditions of optimality are formulated. Basing on the results, some general hypotheses on optimal control in terms of Pontryagin's maximum condition and Bellman's equation are proposed.

  14. Controller for thermostatically controlled loads

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ning; Zhang, Yu; Du, Pengwei; Makarov, Yuri V.

    2016-06-07

    A system and method of controlling aggregated thermostatically controlled appliances (TCAs) for demand response is disclosed. A targeted load profile is formulated and a forecasted load profile is generated. The TCAs within an "on" or "off" control group are prioritized based on their operating temperatures. The "on" or "off" status of the TCAs is determined. Command signals are sent to turn on or turn off the TCAs.

  15. Controlling chimeras

    Science.gov (United States)

    Bick, Christian; Martens, Erik A.

    2015-03-01

    Coupled phase oscillators model a variety of dynamical phenomena in nature and technological applications. Non-local coupling gives rise to chimera states which are characterized by a distinct part of phase-synchronized oscillators while the remaining ones move incoherently. Here, we apply the idea of control to chimera states: using gradient dynamics to exploit drift of a chimera, it will attain any desired target position. Through control, chimera states become functionally relevant; for example, the controlled position of localized synchrony may encode information and perform computations. Since functional aspects are crucial in (neuro-)biology and technology, the localized synchronization of a chimera state becomes accessible to develop novel applications. Based on gradient dynamics, our control strategy applies to any suitable observable and can be generalized to arbitrary dimensions. Thus, the applicability of chimera control goes beyond chimera states in non-locally coupled systems.

  16. Effects of fluctuating flows and a controlled flood on incubation success and early survival rates and growth of age-0 rainbow trout in a large regulated river

    Science.gov (United States)

    Korman, Josh; Kaplinski, Matthew; Melis, Theodore S.

    2011-01-01

    Hourly fluctuations in flow from Glen Canyon Dam were increased in an attempt to limit the population of nonnative rainbow trout Oncorhynchus mykiss in the Colorado River, Arizona, due to concerns about negative effects of nonnative trout on endangered native fishes. Controlled floods have also been conducted to enhance native fish habitat. We estimated that rainbow trout incubation mortality rates resulting from greater fluctuations in flow were 23-49% (2003 and 2004) compared with 5-11% under normal flow fluctuations (2006-2010). Effects of this mortality were apparent in redd excavations but were not seen in hatch date distributions or in the abundance of the age-0 population. Multiple lines of evidence indicated that a controlled flood in March 2008, which was intended to enhance native fish habitat, resulted in a large increase in early survival rates of age-0 rainbow trout. Age-0 abundance in July 2008 was over fourfold higher than expected given the number of viable eggs that produced these fish. A hatch date analysis indicated that early survival rates were much higher for cohorts that hatched about 1 month after the controlled flood (~April 15) relative to those that hatched before this date. The cohorts that were fertilized after the flood were not exposed to high flows and emerged into better-quality habitat with elevated food availability. Interannual differences in age-0 rainbow trout growth based on otolith microstructure supported this hypothesis. It is likely that strong compensation in survival rates shortly after emergence mitigated the impact of incubation losses caused by increases in flow fluctuations. Control of nonnative fish populations will be most effective when additional mortality is applied to older life stages after the majority of density-dependent mortality has occurred. Our study highlights the need to rigorously assess instream flow decisions through the evaluation of population-level responses.

  17. Effects of Artificial Gravity and Bed Rest on Spatial Orientation and Balance Control

    Science.gov (United States)

    Paloski, William H.; Moore, S. T.; Feiveson, A. H.; Taylor, L. C.

    2007-01-01

    While the vestibular system should be well-adapted to bed rest (a condition it experiences approximately 8/24 hrs each day), questions remain regarding the degree to which repeated exposures to the unusual gravito-inertial force environment of a short-radius centrifuge might affect central processing of vestibular information used in spatial orientation and balance control. Should these functions be impaired by intermittent AG, its feasibility as a counter-measure would be diminished. We, therefore, examined the effects of AG on spatial orientation and balance control in 15 male volunteers before and after 21 days of 6 HDT bed rest (BR). Eight of the subjects were treated with daily 1hr AG exposures (2.5g at the feet; 1.0g at the heart) aboard a short radius (3m) centrifuge, while the other seven served as controls (C). Spatial orientation was assessed by measures of ocular counter-rolling (OCR; rotation of the eye about the line of sight, an otolith-mediated reflex) and subjective visual vertical (SVV; perception of the spatial upright). Both OCR and SVV measurements were made with the subject upright, lying on their left sides, and lying on their right sides. OCR was measured from binocular eye orientation recordings made while the subjects fixated for 10s on a point target directly in front of the face at a distance of 1 m. SVV was assessed by asking subjects (in the dark) to adjust to upright (using a handheld controller) the orientation of a luminous bar randomly perturbed (15) to either side of the vertical meridian. Balance control performance was assessed using a computerized dynamic posturography (CDP) protocol similar to that currently required for all returning crew members. During each session, the subjects completed a combination of trials of sensory organization test (SOT) 2 (eyes closed, fixed platform) and SOT 5 (eyes closed, sway-referenced platform) with and without static and dynamic pitch plane head movements (plus or minus 20 deg., dynamic

  18. Juvenile Salmonid Otolith Data - Ocean Survival of Salmonids

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

  19. Antagonistic otolith-visual units in cat vestibular nuclei

    Science.gov (United States)

    Daunton, Nancy G.; Christensen, Carol A.

    1992-01-01

    The nature of neural coding of visual (Vis) and vestibular (Vst) information on translational motion in the region of the vestibular nuclei was investigated using extracellular single-unit recordings in alert adult cats. Responses were recorded and averaged over 60 cycles of stimulation in the vertical and horizontal planes, which included the Vst (movement of the animal in the dark), Vis (movement within lighted visual surround), and combined Vis and Vst (movement of the animal within the lighted stationary visual surround). Data are reported on responses to stimulations along the axis showing maximal sensitivity. A small number of units were identified that showed an antagonistic relationship between their Vis and Vst responses (since they were maximally excited by Vis and by Vst stimulations in the same direction). Results suggest that antagonistic units may belong to an infrequently encountered, but functionally distinct, class of neurons.

  20. Boom in boarfish abundance: insight from otolith analysis

    DEFF Research Database (Denmark)

    Coad, Julie Olivia; Hüssy, Karin

    2012-01-01

    The boarfish Capros aper is a pelagic shoaling species widely distributed along the Northeast Atlantic continental shelf. In recent years, this species has experienced a dramatic boom in abundance in the Bay of Biscay and Celtic Sea. This study aims at resolving the mechanisms responsible...... was not correlated with growth in the same year. However, year‐class strength was significantly correlated with adult growth the previous year, together with temperature during the months following spawning. The age structure shows that this species is very long lived (>30 years), but that a considerable proportion...... abundance...

  1. Describing control

    International Nuclear Information System (INIS)

    Incremental development and maintenance of large systems imply that control be clearly separated from knowledge. Finding efficient control for a given class of knowledge is itself a matter of expertise, to which knowledge-based methods may and should be applied. We present here two attempts at building root systems that may later be tuned by knowledge engineers, using the semantics of each particular application. These systems are given heuristics in a declarative manner, which they use to control the application of heuristics. Eventually, some heuristics may be used to compile others (or themselves) into efficient pieces of programmed code

  2. Controlling Chimeras

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Bick, Christian

    2015-01-01

    Coupled phase oscillators model a variety of dynamical phenomena in nature and technological applications. Non-local coupling gives rise to chimera states which are characterized by a distinct part of phase-synchronized oscillators while the remaining ones move incoherently. Here, we apply the idea...... of control to chimera states: using gradient dynamics to exploit drift of a chimera, it will attain any desired target position. Through control, chimera states become functionally relevant; for example, the controlled position of localized synchrony may encode information and perform computations....... Since functional aspects are crucial in (neuro-)biology and technology, the localized synchronization of a chimera state becomes accessible to develop novel applications. Based on gradient dynamics, our control strategy applies to any suitable observable and can be generalized to arbitrary dimensions...

  3. IT controlling

    OpenAIRE

    Stehlík, Libor

    2010-01-01

    The main aim of this thesis is to acquaint the reader with the possibilities of economic management of enterprise information technology field by using tools provided by financial controlling and to propose an appropriate metrics for performance measurement of this area. The thesis is logically divided into three comprehensive parts. Firstly, the reader is acquainted with the historical evolution and general principles of controlling management approach, which is then applied to IT field. Alo...

  4. Controlling chimeras

    OpenAIRE

    Bick, Christian; Martens, Erik Andreas

    2015-01-01

    Coupled phase oscillators model a variety of dynamical phenomena in nature and technological applications. Non-local coupling gives rise to chimera states which are characterized by a distinct part of phase-synchronized oscillators while the remaining ones move incoherently. Here, we apply the idea of control to chimera states: using gradient dynamics to exploit drift of a chimera, it will attain any desired target position. Through control, chimera states become functionally relevant; for ex...

  5. Controlling pollution by controlling combustion

    Energy Technology Data Exchange (ETDEWEB)

    Orrin, John (South Bank Univ., London (United Kingdom))

    1994-05-04

    Modern control theory is now being used to reduce pollution from fossil fuel combustion. Powerful microprocessors using digital control algorithms are now used to make combustion systems, such as industrial furnaces and car engines, operate with optimal performance. These systems operate to achieve a balance between lean fuel burning with the reduced pollution produced, but more engine noise and vibration, and an air/fuel mixture that produces good engine performance but worse pollution. (UK)

  6. Control rod

    International Nuclear Information System (INIS)

    In a control rod of a nuclear reactor, B-10 is distributed such that the concentration of B-10 in boron carbide is lowered from the outer side to the inner side of the control rod. Alternatively, the inside of a blade is radially divided into a plurality of regions, and the amount of boron carbide loaded in the regions is reduced from the outer side to the inner side of the control rod. Alternatively, a plurality of sintered products of boron carbide are disposed radially in the blade, and the sintered product is divided to a first region where the B-10 content is relatively low and a second region having a higher B-10 content than the first region, and the sintered product disposed on the inner side is constituted such that the position of the first region in the sintered product is localized to the inner side of the control rod. Then, improvement of reliability and reduction of cost can be attained while maintaining an effective neutron absorbing performance of control rods taking neutron flux distribution into consideration. (N.H.)

  7. Controlled teleportation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this article,we review the recent development of controlled teleportation which can be used for sharing quantum information and has important applications in remote quantum computation.We introduce the principles of a couple of controlled teleportation schemes with maximally entangled quantum channels and those with pure entangled quantum channels (non-maximally entangled states).The schemes based on maximally entangled states have the advantage of having maximal efficiency although there are differences in their implementations in experiment.In the controlled teleportation schemes using non-maximally entangled states as the quantum channels,the receiver can reconstruct the originally unknown state by adding an auxiliary particle and performing a unitary evolution.No matter what the unknown state is (a single qubit state or an m-qudit state),the auxiliary particle required is only a two-level quantum system.

  8. Spatial Cognition, Body Representation and Affective Processes: The Role of Vestibular Information beyond Ocular Reflexes and Control of Posture

    Directory of Open Access Journals (Sweden)

    Fred W Mast

    2014-05-01

    Full Text Available A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: 1 Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths, body rotation (changing the input from the semicircular canals, in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. 2 Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. 3 Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are – at least in part – associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  9. Decentralized control

    Science.gov (United States)

    Steffen, Chris

    1990-01-01

    An overview of the time-delay problem and the reliability problem which arise in trying to perform robotic construction operations at a remote space location are presented. The effects of the time-delay upon the control system design will be itemized. A high level overview of a decentralized method of control which is expected to perform better than the centralized approach in solving the time-delay problem is given. The lower level, decentralized, autonomous, Troter Move-Bar algorithm is also presented (Troters are coordinated independent robots). The solution of the reliability problem is connected to adding redundancy to the system. One method of adding redundancy is given.

  10. Optimal Control

    CERN Document Server

    Vinter, Richard

    2010-01-01

    "Each chapter contains a well-written introduction and notes. They include the author's deep insights on the subject matter and provide historical comments and guidance to related literature. This book may well become an important milestone in the literature of optimal control." --Mathematical Reviews "Thanks to a great effort to be self-contained, [this book] renders accessibly the subject to a wide audience. Therefore, it is recommended to all researchers and professionals interested in Optimal Control and its engineering and economic applications. It can serve as an excellent

  11. COPD - control drugs

    Science.gov (United States)

    Chronic obstructive pulmonary disease - control drugs; Bronchodilators - COPD - control drugs; Beta agonist inhaler - COPD - control drugs; Anticholinergic inhaler - COPD - control drugs; Long-acting inhaler - COPD - control drugs; ...

  12. Controlling turbulence

    Science.gov (United States)

    Kühnen, Jakob; Hof, Björn

    2015-11-01

    We show that a simple modification of the velocity profile in a pipe can lead to a complete collapse of turbulence and the flow fully relaminarises. The annihilation of turbulence is achieved by a steady manipulation of the streamwise velocity component alone, greatly reducing control efforts. Several different control techniques are presented: one with a local modification of the flow profile by means of a stationary obstacle, one employing a nozzle injecting fluid through a small gap at the pipe wall and one with a moving wall, where a part of the pipe is shifted in the streamwise direction. All control techniques act on the flow such that the streamwise velocity profile becomes more flat and turbulence gradually grows faint and disappears. In a smooth straight pipe the flow remains laminar downstream of the control. Hence a reduction in skin friction by a factor of 8 and more can be accomplished. Stereoscopic PIV-measurements and movies of the development of the flow during relaminarisation are presented.

  13. CONTROLLING DIFFUSION

    NARCIS (Netherlands)

    WESSELINGH, JA

    1993-01-01

    In this paper I first briefly look at diffusion in several controlled release devices. I have found that these exploit complicated diffusional mechanisms. These cannot be understood using the conventional description of diffusion. So, a general theory of multicomponent diffusion which can describe t

  14. Internal Controls

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Managing risk is essential for positioning a company for growth in the current business environment.Yet as companies around the world clamber to inplement integrated risk controls in light of corlporate meltdowns and terrorist concems,many firms fail to pull the weeds out of their own backyard in China before trying to harvest the profitable crops!

  15. Controllable dose

    International Nuclear Information System (INIS)

    With the purpose of eliminating the controversy about the lineal hypothesis without threshold which found the systems of dose limitation of the recommendations of ICRP 26 and 60, at the end of last decade R. Clarke president of the ICRP proposed the concept of Controllable Dose: as the dose or dose sum that an individual receives from a particular source which can be reasonably controllable by means of any means; said concept proposes a change in the philosophy of the radiological protection of its concern by social approaches to an individual focus. In this work a panorama of the foundations is presented, convenient and inconveniences that this proposal has loosened in the international community of the radiological protection, with the purpose of to familiarize to our Mexican community in radiological protection with these new concepts. (Author)

  16. Controlled fusion

    International Nuclear Information System (INIS)

    During the last fifty years the researches on controlled thermonuclear fusion reached great performance in the magnetic confinement (tokamaks) as in the inertial confinement (lasers). But the state of the art is not in favor of the apparition of the fusion in the energy market before the second half of the 21 century. To explain this opinion the author presents the fusion reactions of light nuclei and the problems bound to the magnetic confinement. (A.L.B.)

  17. Gun Control

    OpenAIRE

    Moore, Mark; Cook, Phil; Braga, Anthony

    2001-01-01

    The purpose of this essay is to provide a foundation for understanding the "Great American Gun War," and to consider the next steps that could be taken in the search for an effective gun-control policy. We begin with a review of the more-or-less uncontroversial facts about trends in gun ownership and use, and the reasons why Americans are inclined to arm themselves. A discussion follows of the more contentious issues, whether and how guns influence levels or seriousness of crime. We then iden...

  18. Control presupuestario

    OpenAIRE

    Pérez-Bonaventura, Marc

    2015-01-01

    Los presupuestos son una herramienta de control muy útil en las empresas. Este recurso didáctico se ha creado con la intención de explicar el presupuesto previsto, el presupuesto real, el presupuesto flexible, el presupuesto revisado y sus desviaciones de una forma simple y didáctica. Este documento muestra a nivel teórico, esquemático y con ejemplos numéricos la formación de los diferentes presupuestos y las desviaciones existentes entre ellos.

  19. Control rod

    International Nuclear Information System (INIS)

    Purpose: To enable semi-permanent and safety use of a control rod in a water cooled type reactor operated under high temperature and high pressure conditions by using a blade in which hafnium materials at a nuclear reactor quality are covered with stainless steels or zirconium alloys. Constitution: A plate-like hafnium material is surrounded with a thin plate of stainless steels or zirconium alloys under vacuum and the joint portions of the thin plate is subjected to seam welding. Then a blade is prepared by welding the remaining joining portions at both ends in a conventional manner. The welding method usable herein includes electron beam welding, laser welding and the like. If it is required to increase the close bondability between the halfnium plate and the thin plate, the blade thus obtained is subjected as it is to extrusion fabrication thereby obtain a desired increased bondability. (Kawakami, Y.)

  20. Roof control

    Energy Technology Data Exchange (ETDEWEB)

    Woof, M.

    1999-10-01

    Joy has produced a roof support with a new shape and which offers both high productivity and good operator safety. It features high levels of ambient lighting, low working noise levels, a simple control layout, a wide operating platform, and good all-round visibility. The first underground tests with the trial machine at Capcoal's Central Colliery in Australia set production records, with 304 of the 1.8 m bolts in 3 hours 45 minutes. This was broken by Arch Coal's Sufco mine in Utah, USA when a unit installed 304 of 1.8 m fully encapsulated bolts in 3 hr 20 mins. The article gives detail on design features. 1 photo.

  1. Custom controls

    Science.gov (United States)

    Butell, Bart

    1996-02-01

    Microsoft's Visual Basic (VB) and Borland's Delphi provide an extremely robust programming environment for delivering multimedia solutions for interactive kiosks, games and titles. Their object oriented use of standard and custom controls enable a user to build extremely powerful applications. A multipurpose, database enabled programming environment that can provide an event driven interface functions as a multimedia kernel. This kernel can provide a variety of authoring solutions (e.g. a timeline based model similar to Macromedia Director or a node authoring model similar to Icon Author). At the heart of the kernel is a set of low level multimedia components providing object oriented interfaces for graphics, audio, video and imaging. Data preparation tools (e.g., layout, palette and Sprite Editors) could be built to manage the media database. The flexible interface for VB allows the construction of an infinite number of user models. The proliferation of these models within a popular, easy to use environment will allow the vast developer segment of 'producer' types to bring their ideas to the market. This is the key to building exciting, content rich multimedia solutions. Microsoft's VB and Borland's Delphi environments combined with multimedia components enable these possibilities.

  2. Power Controller

    Science.gov (United States)

    1982-01-01

    The device called the Power Factor Controller (PFC) offers exceptional energy conservation potential by virtue of its ability to sense shifts in the relationship between voltage and current flow, and to match them with the motor's need. Originating from the solar heating/cooling program, the PFC senses a light load, it cuts the voltage level to the minimum needed which in turn reduces current flow and heat loss. Laboratory tests showed that the PFC could reduce power used by six to eight percent under normal motor loads, and as much as 65 percent when the motor was idling. Over 150 companies have been granted NASA licenses for commercial use of this technology. One system that utilizes this technology is the Vectrol Energy System, (VES) produced by Vectrol, Inc. a subsidiary of Westinghouse. The VES is being used at Woodward & Lothrop, on their escalators. Energy use is regulated according to how many people are on the escalator at any time. It is estimated that the energy savings are between 30 to 40 percent.

  3. Relationship between fuzzy controllers and PID controllers

    Institute of Scientific and Technical Information of China (English)

    李洪兴

    1999-01-01

    The internal relations between fuzzy controllers and PID controllers are revealed. First, it is pointed out that a fuzzy controller with one input and one output is just a piecewise P controller. Then it is proved that a fuzzy controller with two inputs and one output is just a piecewise PD (or I) controller with interaction between P and D (or PI). At last, the conclusion that a fuzzy controller with three inputs and one output is just a piecewise PID controller with interaction among P, I and D is given. Moreover, a kind of difference scheme of fuzzy controllers is designed.

  4. Radiation control

    International Nuclear Information System (INIS)

    This paper describes on how the condition of radiation level in the ring (storage ring) experimentation room changes corresponding to the operating stage of SOR-ring (synchrotron radiation storage ring), and does not describe on the present radiation control in the SOR facility. The operating stage of SOR is divided into the following five: (1) 307 MeV electron injection, (2) 307 MeV electron storage (used for SOR experiments), (3) energy increase from 307 to 380 MeV, (4) 380 MeV electron storage, (5) re-injection and completion of operation. Gamma and X ray levels are shown when electron beam is injected from the electron synchrotron to the SOR-ring. Two main causes of the high level are reported. Spatial dose rate in storing 307 MeV electrons in also illustrated. This is sufficiently lower than that at electron incidence. The measurement of radiation level at the time of energy increase from 307 to 380 MeV has just started. Since the radiation level in 380 MeV storage, measured at the points about 20 cm apart from the electron orbit, showed several mR/h, the level seems to be negligible at the points where experiments are carried out, 1 m away from the measurement points. The radiation level in electron reinjection and completion of operation may be large during a short period (a few Roentgen) like the time of energy increase. Therefore, the beam shall be re-injected or decreased after confirming that all experimenters have retreated into the predetermined place. (Wakatsuki, Y.)

  5. Intelligent Controller for Networked DC Motor Control

    OpenAIRE

    B. Sharmila; N. Devarajan

    2010-01-01

    This paper focuses on the feasibility of Neural Network controller for Networked Control Systems. The Intelligent Controllers has been developed for controlling the speed of the Networked DC Motor by exploiting the features of Neural Networks and Fuzzy Logic Controllers. The major challenges in Networked Control Systems are the network induced delays and data packet losses in the closed loop. These challenges degrade the performance and destabilize the systems. The aim of the proposed Neural ...

  6. Incoherent control of locally controllable quantum systems

    International Nuclear Information System (INIS)

    An incoherent control scheme for state control of locally controllable quantum systems is proposed. This scheme includes three steps: (1) amplitude amplification of the initial state by a suitable unitary transformation, (2) projective measurement of the amplified state, and (3) final optimization by a unitary controlled transformation. The first step increases the amplitudes of some desired eigenstates and the corresponding probability of observing these eigenstates, the second step projects, with high probability, the amplified state into a desired eigenstate, and the last step steers this eigenstate into the target state. Within this scheme, two control algorithms are presented for two classes of quantum systems. As an example, the incoherent control scheme is applied to the control of a hydrogen atom by an external field. The results support the suggestion that projective measurements can serve as an effective control and local controllability information can be used to design control laws for quantum systems. Thus, this scheme establishes a subtle connection between control design and controllability analysis of quantum systems and provides an effective engineering approach in controlling quantum systems with partial controllability information.

  7. Manual control in space research on perceptual-motor functions under zero gravity conditions (L-10)

    Science.gov (United States)

    Tada, Akira

    1993-01-01

    Are human abilities to control vehicles and other machines the same in space as those on Earth? The L-10 Manual Control Experiment of the First Materials Processing Tests (FMPT) started from this question. Suppose a pilot has the task to align the head of a space vehicle toward a target. His actions are to look at the target, to determine the vehicle movement, and to operate the manipulator. If the activity of the nervous system were the same as on Earth, the movements, of the eye and hand would become excessive because the muscles do not have to oppose gravity. The timing and amount of movement must be arranged for appropriate actions. The sensation of motion would also be affected by the loss of gravity because the mechanism of the otolith, the major acceleration sensor, depends on gravity. The possible instability of the sensation of direction may cause mistakes in the direction of control of manipulator movement. Thus, the experimental data can be used for designing man-machine systems in space, as well as for investigation of physiological mechanisms. In this experiment, the direction of vehicle heading is expressed by a light spot on an array of light emitting diodes and the manipulator is of a finger stick type. As the light spot moves up and down, the Japanese Payload Specialist, and the subject, must move the manipulator forward and backward to keep the movement of the light spot within the neighborhood of the central point of the display. The position of the light spot is computed in such a manner that when the stick is kept at the neutral position, a motion whose acceleration is proportional to the angle of deflection is added to the movement of the light spot. The Operator Describing Function, which is an expression of human control characteristics, can be calculated from 2 minutes of raw data of the light spot position and stick deflection. The 2 minutes of operation is called a run, and 8 runs with resting periods composes a session. The on

  8. Contact Control, Version 1

    Energy Technology Data Exchange (ETDEWEB)

    2016-07-21

    The contact control code is a generalized force control scheme meant to interface with a robotic arm being controlled using the Robot Operating System (ROS). The code allows the user to specify a control scheme for each control dimension in a way that many different control task controllers could be built from the same generalized controller. The input to the code includes maximum velocity, maximum force, maximum displacement, and a control law assigned to each direction and the output is a 6 degree of freedom velocity command that is sent to the robot controller.

  9. Are estimated control charts in control?

    NARCIS (Netherlands)

    Albers, W.; Kallenberg, W.C.M.

    2001-01-01

    Standard control chart practice assumes normality and uses estimated parameters. Because of the extreme quantiles involved, large relative errors result. Here simple corrections are derived to bring such estimated charts under control. As a criterion, suitable exceedance probabilities are used.

  10. Cognitive Control in the Controllable Connectome

    OpenAIRE

    Medaglia, John D.; Gu, Shi; Pasqualetti, Fabio; Ashare, Rebecca L.; Lerman, Caryn; Kable, Joseph; Bassett, Danielle S

    2016-01-01

    Cognition is supported by neurophysiological processes that occur both in local anatomical neighborhoods and in distributed large-scale circuits. Recent evidence from network control theory suggests that white matter pathways linking large-scale brain regions provide a critical substrate constraining the ability of single areas to affect control on those processes. Yet, no direct evidence exists for a relationship between brain network controllability and cognitive control performance. Here, ...

  11. Quantum feedback control and classical control theory

    OpenAIRE

    Doherty, Andrew C.; Habib, Salman; Jacobs, Kurt; Mabuchi, Hideo; Tan, Sze M.

    1999-01-01

    We introduce and discuss the problem of quantum feedback control in the context of established formulations of classical control theory, examining conceptual analogies and essential differences. We describe the application of state-observer-based control laws, familiar in classical control theory, to quantum systems and apply our methods to the particular case of switching the state of a particle in a double-well potential.

  12. Introduction of digital control

    International Nuclear Information System (INIS)

    This book is one of mechatronics series. It deals with digital control, which includes what is digital control?, display way of control system, output of primary system, secondary system like example of system and display way of the system, stabilizing of control system such as method to decide stability and system out of control, displaying equation of state into vector, good control such as the right characteristic, transient behavior and design of position control system using DC servo motor.

  13. GCFR plant control system

    International Nuclear Information System (INIS)

    A plant control system is being designed for a gas-cooled fast breeder reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. The load control portion of the plant control system provides stable automatic (closed-loop) control of the plant over the 25% to 100% load range. Simulation results are presented to demonstrate load control system performance. The results show that the plant is controllable at full load with the control system structure selected, but gain scheduling is required to achieve desired performance over the load range

  14. Substructural controller synthesis

    Science.gov (United States)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1989-01-01

    A decentralized design procedure which combines substructural synthesis, model reduction, decentralized controller design, subcontroller synthesis, and controller reduction is proposed for the control design of flexible structures. The structure to be controlled is decomposed into several substructures, which are modeled by component mode synthesis methods. For each substructure, a subcontroller is designed by using the linear quadratic optimal control theory. Then, a controller synthesis scheme called Substructural Controller Synthesis (SCS) is used to assemble the subcontrollers into a system controller, which is to be used to control the whole structure.

  15. A Digital Controller for Active Aeroelastic Controls

    OpenAIRE

    Ueda, Tetsuhiko; MUROTA, Katsuichi; 上田, 哲彦; 室田, 勝一

    1989-01-01

    A high-speed digital controller for aeroelastic controls was designed and made. The purpose was to minimize adverse phase lag which is inevitably produced by the CPU time of digital processing. The delay deteriorates control performances on rather rapid phenomena like aircraft flutter. With fix-point operation the controller realized 417 microseconds of throughput time including the A/D and D/A conversion. This corresponds to a high sampling rate of 2.4kHz. The controller furnishes two channe...

  16. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  17. Fuzzy Supervisory Control

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1998-01-01

    Control problems in the process industry are dominated by non-linear and time-varying behaviour, many inner loops, and much interaction between the control loops. Fuzzy controllers have in some cases nevertheless mimicked the control actions of a human operator. For high level control and...

  18. Structural Pest Control.

    Science.gov (United States)

    Kahn, M. S.; Hoffman, W. M.

    This manual is designed for those who seek certification as pesticide applicators for industrial, institutional, structural, and health-related pest control. It is divided into six sections covering general pest control, wood-destroying organisms, bird control, fumigation, rodent control, and industrial weed control. The manual gives information…

  19. Modular thyristor controlled series capacitor control system

    Energy Technology Data Exchange (ETDEWEB)

    Clark, K.; Larsen, E.V.; Wegner, C.A.; Piwko, R.J.

    1995-06-13

    A modular thyristor controlled series capacitor (TCSC) system, including a method and apparatus, uses phase controlled firing based on monitored capacitor voltage and line current. For vernier operation, the TCSC system predicts an upcoming firing angle for switching a thyristor controlled commutating circuit to bypass line current around a series capacitor. Each bypass current pulse changes the capacitor voltage proportionally to the integrated value of the current pulse. The TCSC system promptly responds to an offset command from a higher-level controller to control bypass thyristor duty to minimize thyristor damage, and to prevent capacitor voltage drift during line current disturbances. In a multi-module TCSC system, the higher level controller accommodates competing objectives of various system demands, including minimizing losses in scheduling control, stabilizing transients, damping subsynchronous resonance (SSR) oscillations, damping direct current (DC) offset, and damping power-swings. 67 figs.

  20. Controlling chaos using an exponential control

    CERN Document Server

    Gadre, S D; Gadre, Sangeeta D; Varma, V S

    1995-01-01

    We demonstrate that chaos can be controlled using a multiplicative exponential feedback control. All three types of unstable orbits - unstable fixed points, limit cycles and chaotic trajectories can be stabilized using this control. The control is effective both for maps and flows. The control is significant, particularly for systems with several degrees of freedom, as knowledge of only one variable on the desired unstable orbit is sufficient to settle the system on to that orbit. We find, that in all the cases studied, the transient time is a decreasing function of the stiffness of control. But increasing the stiffness beyond an optimum value can increase the transient time. The control can also be used to create suitable new stable attractors in a map, which did not exist in the original system.