WorldWideScience

Sample records for arabiensis aquatic habitat

  1. Survival of immature Anopheles arabiensis (Diptera: Culicidae in aquatic habitats in Mwea rice irrigation scheme, central Kenya

    Directory of Open Access Journals (Sweden)

    Jacob Benjamin

    2006-11-01

    , the application of larvicides should target An. arabiensis larvae at the tillering stage (early vegetative stage of rice when their survival in the aquatic habitats is high to significantly reduce them and the larvicides should be long-lasting to have a significant impact on the malaria vector productivity on the habitats.

  2. A heteroskedastic error covariance matrix estimator using a first-order conditional autoregressive Markov simulation for deriving asympotical efficient estimates from ecological sampled Anopheles arabiensis aquatic habitat covariates

    Directory of Open Access Journals (Sweden)

    Githure John I

    2009-09-01

    Full Text Available Abstract Background Autoregressive regression coefficients for Anopheles arabiensis aquatic habitat models are usually assessed using global error techniques and are reported as error covariance matrices. A global statistic, however, will summarize error estimates from multiple habitat locations. This makes it difficult to identify where there are clusters of An. arabiensis aquatic habitats of acceptable prediction. It is therefore useful to conduct some form of spatial error analysis to detect clusters of An. arabiensis aquatic habitats based on uncertainty residuals from individual sampled habitats. In this research, a method of error estimation for spatial simulation models was demonstrated using autocorrelation indices and eigenfunction spatial filters to distinguish among the effects of parameter uncertainty on a stochastic simulation of ecological sampled Anopheles aquatic habitat covariates. A test for diagnostic checking error residuals in an An. arabiensis aquatic habitat model may enable intervention efforts targeting productive habitats clusters, based on larval/pupal productivity, by using the asymptotic distribution of parameter estimates from a residual autocovariance matrix. The models considered in this research extends a normal regression analysis previously considered in the literature. Methods Field and remote-sampled data were collected during July 2006 to December 2007 in Karima rice-village complex in Mwea, Kenya. SAS 9.1.4® was used to explore univariate statistics, correlations, distributions, and to generate global autocorrelation statistics from the ecological sampled datasets. A local autocorrelation index was also generated using spatial covariance parameters (i.e., Moran's Indices in a SAS/GIS® database. The Moran's statistic was decomposed into orthogonal and uncorrelated synthetic map pattern components using a Poisson model with a gamma-distributed mean (i.e. negative binomial regression. The eigenfunction

  3. Abiotic and biotic factors associated with the presence of Anopheles arabiensis immatures and their abundance in naturally occurring and man-made aquatic habitats

    Directory of Open Access Journals (Sweden)

    Gouagna Louis

    2012-07-01

    Full Text Available Abstract Background Anopheles arabiensis (Diptera: Culicidae is a potential malaria vector commonly present at low altitudes in remote areas in Reunion Island. Little attention has been paid to the environmental conditions driving larval development and abundance patterns in potential habitats. Two field surveys were designed to determine whether factors that discriminate between aquatic habitats with and without An. arabiensis larvae also drive larval abundance, comparatively in man-made and naturally occurring habitats. Methods In an initial preliminary survey, a representative sample of aquatic habitats that would be amenable to an intensive long-term study were selected and divided into positive and negative sites based on the presence or absence of Anopheles arabiensis larvae. Subsequently, a second survey was prompted to gain a better understanding of biotic and abiotic drivers of larval abundance, comparatively in man-made and naturally occurring habitats in the two studied locations. In both surveys, weekly sampling was performed to record mosquito species composition and larval density within individual habitats, as well as in situ biological characteristics and physico-chemical properties. Results Whilst virtually any stagnant water body could be a potential breeding ground for An. arabiensis, habitats occupied by their immatures had different structural and biological characteristics when compared to those where larvae were absent. Larval occurrence seemed to be influenced by flow velocity, macrofauna diversity and predation pressure. Interestingly, the relative abundance of larvae in man-made habitats (average: 0.55 larvae per dip, 95%CI [0.3–0.7] was significantly lower than that recorded in naturally occurring ones (0.74, 95%CI [0.5–0.8]. Such differences may be accounted for in part by varying pressures that could be linked to a specific habitat. Conclusions If the larval ecology of An. arabiensis is in general very complex

  4. Aquatic Habitat Bottom Classification Using ADCP

    Science.gov (United States)

    Description of physical aquatic habitat often includes data describing distributions of water depth, velocity and bed material type. Water depth and velocity in streams deeper than about 1 m may be continuously mapped using an acoustic Doppler current profiler from a moving boat. Herein we examine...

  5. Fish and Aquatic Habitat Survey: Sheldon National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To address the need for baseline inventories of biota and abiotic features, the Columbia River Fisheries Program Office (CRFPO) conducted fish and aquatic habitat...

  6. Spatial and temporal distribution patterns of Anopheles arabiensis breeding sites in La Reunion Island - multi-year trend analysis of historical records from 1996-2009

    Directory of Open Access Journals (Sweden)

    Lempérière Guy

    2011-06-01

    Full Text Available Abstract Background An often confounding facet of the dynamics of malaria vectors is the aquatic larval habitat availability and suitable conditions under which they can thrive. Here, we investigated the impact of environmental factors on the temporal and spatial distribution of larval habitats of Anopheles arabiensis in different locations on La Reunion Island. Methods A retrospective examination was made from archival data which provided the complete enumeration of An. arabiensis breeding habitats in three distinct geographic zones - extending North-east, West and South of the island over 14 years, from January 1996 to December 2009. Data on the occurrence and the number of active larval habitats at each of a total of 4376 adjacent ellipsoid grid cells (216,506 square meters each were used (1 to provide the geographic extent of breeding site availability from year to year and (2 to analyze associations with prevailing environmental factors, habitat types, and locations. Results Anopheles arabiensis utilized a spectrum of man-made and natural aquatic habitats, most of which were concentrated primarily in the rock pools located in ravines and river fringes, and also in the large littoral marshes and within the irrigated agricultural zones. The numbers of breeding site per sampling grid differed significantly in different parts of the island. In contrast to an originally more widespread distribution across the island in the 1950s, detailed geographic analyses of the data obtained in the period extending from 1996-2009 showed an intriguing clustered distribution of active breeding sites in three discontinuous geographic zones, in which aquatic habitats availability fluctuates with the season and year. Seasonality in the prevalence of anopheles breeding sites suggests significant responsiveness to climatic factors. Conclusions The observed retreat of An. arabiensis distribution range to lower altitudinal zones (

  7. Species management in aquatic habitats WRc RD Interim 1997

    OpenAIRE

    1997-01-01

    This is the Species management in aquatic Habitats WRc Interim 1997 document produced by the Environment Agency in 1997. This document reports progress on R&D Project 640, which aims to provide information on species of conservation value of particular relevance to the Environment Agency, in relation to its activities affecting aquatic environments. A range of stand-alone outputs is being produced, comprising Species Action Plans, practical management guidelines for Agency staff and third par...

  8. Biological conservation of aquatic inland habitats: these are better days

    Directory of Open Access Journals (Sweden)

    Ian J. Winfield

    2013-08-01

    Full Text Available The biodiversity of aquatic inland habitats currently faces unprecedented threats from human activities. At the same time, although much is known about the functioning of freshwater ecosystems the successful transfer of such knowledge to practical conservation has not been universal. Global awareness of aquatic conservation issues is also hampered by the fact that conditions under the water surface are largely hidden from the direct experience of most members of society. Connectivity, or lack of it, is another challenge to the conservation of freshwater habitats, while urban areas can play a perhaps unexpectedly important positive role. Freshwater habitats frequently enjoy benefits accruing from a sense of ownership or stewardship by local inhabitants, which has led to the development of conservation movements which commonly started life centred on the aquatic inland habitat itself but of which many have now matured into wider catchment-based conservation programmes. A demonstrable need for evidence-based conservation management in turn requires scientific assessments to be increasingly robust and standardised, while at the same time remaining open to the adoption of technological advances and welcoming the rapidly developing citizen science movement. There is evidence of real progress in this context and conservation scientists are now communicating their findings to environmental managers in a way and on a scale that was rarely seen a couple of decades ago. It is only in this way that scientific knowledge can be efficiently transferred to conservation planning, prioritisation and ultimately management in an increasingly scaled-up, joined-up and resource-limited world. The principle of ‘prevention is better than cure’ is particularly appropriate to most biological conservation issues in aquatic inland habitats and is inextricably linked to educating and/or nudging appropriate human behaviours. When prevention fails, some form of emergency

  9. Predicting Scenarios for Successful Autodissemination of Pyriproxyfen by Malaria Vectors from Their Resting Sites to Aquatic Habitats; Description and Simulation Analysis of a Field-Parameterizable Model.

    Directory of Open Access Journals (Sweden)

    Samson S Kiware

    Full Text Available Large-cage experiments indicate pyriproxifen (PPF can be transferred from resting sites to aquatic habitats by Anopheles arabiensis--malaria vector mosquitoes to inhibit emergence of their own offspring. PPF coverage is amplified twice: (1 partial coverage of resting sites with PPF contamination results in far higher contamination coverage of adult mosquitoes because they are mobile and use numerous resting sites per gonotrophic cycle, and (2 even greater contamination coverage of aquatic habitats results from accumulation of PPF from multiple oviposition events.Deterministic mathematical models are described that use only field-measurable input parameters and capture the biological processes that mediate PPF autodissemination. Recent successes in large cages can be rationalized, and the plausibility of success under full field conditions can be evaluated a priori. The model also defines measurable properties of PPF delivery prototypes that may be optimized under controlled experimental conditions to maximize chances of success in full field trials. The most obvious flaw in this model is the endogenous relationship that inevitably occurs between the larval habitat coverage and the measured rate of oviposition into those habitats if the target mosquito species is used to mediate PPF transfer. However, this inconsistency also illustrates the potential advantages of using a different, non-target mosquito species for contamination at selected resting sites that shares the same aquatic habitats as the primary target. For autodissemination interventions to eliminate malaria transmission or vector populations during the dry season window of opportunity will require comprehensive contamination of the most challenging subset of aquatic habitats [Formula: see text] that persist or retain PPF activity (Ux for only one week [Formula: see text], where Ux = 7 days. To achieve >99% contamination coverage of these habitats will necessitate values for the

  10. Selenium in aquatic habitats at Imperial National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During 1991 and 1992, selenium levels were studied in aquatic communities at Imperial National Wildlife Refuge on the lower Colorado River. Composite samples of...

  11. The influence of habitat integrity and physical-chemical water variables on the structure of aquatic and semi-aquatic Heteroptera

    OpenAIRE

    Karina Dias-Silva; Helena S. R. Cabette; Leandro Juen; Paulo De Marco Jr.

    2010-01-01

    This work aimed to assess the effect of certain physical-chemical variables and the Habitat Integrity Index (HII) have on an aquatic and semi-aquatic heteropteran community. We collected in five streams (from 1st to 4th order) that differed in habitat integrity, in order to test 1) whether heteropteran richness decreases with the Habitat Integrity Index; and 2) whether richness responds to alterations in water physical-chemical variables, since these influence community structure. In each str...

  12. The Occurrence of Bioactive Micromonosporae in Aquatic Habitats of the Sunshine Coast in Australia

    Directory of Open Access Journals (Sweden)

    D. Ipek Kurtböke

    2008-06-01

    Full Text Available Screening strategies based on the ecological knowledge of antibiotic producing microorganisms and their roles in the natural environment are being increasingly employed in the search for novel antibiotic agents. Micromonosporae are common inhabitants of aquatic habitats and have proved to be a continuing source of novel bioactive compounds including antibacterial and antitumor agents. The ecological distribution and frequency of bioactive micromonosporae in Sunshine Coast region aquatic habitats were studied through a range of selective isolation procedures designed to negatively select against the isolation of unwanted microbial taxa commonly associated with marine environments. It was revealed that bioactive compound producing species of micromonosporae were present in the aquatic habitats of the Sunshine Coast region in Australia.

  13. Summary of information on aquatic biota and their habitats in the Willamette Basin, Oregon, through 1995

    Science.gov (United States)

    Altman, Bob; Henson, C.M.; Waite, I.R.

    1997-01-01

    Available information on aquatic biota of the Willamette Basin was reviewed and summarized to describe current and historical conditions as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Biological parameters emphasized include the status, distribution, and trends of aquatic biota, particularly algae, macroinvertebrates, and fish; the condition of aquatic and riparian habitat in which these biota reside; and the response of these biota to natural and human-associated impacts, including the level, type, and effect of contaminants.

  14. Coupling interaction between biodiversity and aquatic habitat area in Western Route Project vicinity

    Institute of Scientific and Technical Information of China (English)

    Shi-min TIAN; Zhao-yin WANG; Xiang-jun LIU; Shi-kui LIANG

    2010-01-01

    The Western Route of the South-to-North Water Transfer Project will divert water from the upper Yangtze River and its tributaries,the Dadu River and Yalong River,to the upper Yellow River.The project may ease the water shortage in the Yellow River Basin.However,it may also have some effects on the ecosystem in the upper Yangtze River Basin.Benthic invertebrates play an important role in the river ecosystem,particularly in the circulation of materials and nutrition.Benthic invertebrates are widely used to quickly assess river ecosystems because of their rapid response to changes in the water environment.The diversity of benthic invertebrates is closely associated with the aquatic habitat area.This study examined this interaction by sampling the benthic invertebrates in an expanding area.The conclusions are that the diversity of benthic invertebrates begins to decrease when the aquatic habitat area is reduced to 45% of the original area,and decreases dramatically when the aquatic habitat area is reduced to 10% of the original area.The aquatic habitat area should be kept at more than 45% of the original area in order to maintain the significant diversity of benthic invertebrates.

  15. Freshwater Wetland Habitat Loss and Fragmentation: Implications for Aquatic Biodiversity Conservation

    Science.gov (United States)

    Wolaver, B. D.; Pierre, J. P.; Labay, B. J.; Ryberg, W. A.; Hibbits, T. J.; Prestridge, H. L.

    2015-12-01

    Anthropogenic land use changes have caused widespread wetland loss and fragmentation. This trend has important implications for aquatic biota conservation, including the semi-aquatic Western Chicken Turtle (Deirochelys reticularia miaria). This species inhabits seasonally inundated, ephemeral water bodies and adjacent uplands in the southeastern U.S. However, wetland conversion to agriculture and urbanization is thought to cause the species' decline, particularly in Texas, which includes the westernmost part of its range. Because the species moves only a few kilometers between wetlands, it particularly sensitive to habitat loss and fragmentation. Thus, as part of the only state-funded species research program, this study provides the U.S. Fish and Wildlife Service (FWS) with scientific data to determine if the species warrants protection under the Endangered Species Act (ESA). We use a species distribution model to map potentially suitable habitat for most of East Texas. We evaluate landscape-scale anthropogenic activities in this region which may be contributing to the species' decline. We identify areas of urbanization, agricultural expansion, forestry, and resulting wetland loss. We find that between 2001 and 2011 approximately 80 km2 of wetlands were lost in potentially suitable habitat, including the urbanizing Houston area. We use spatial geostatistics to quantify wetland habitat fragmentation. We also introduce the Habitat Alteration Index (HAI), which calculates total landscape alteration and mean probability of occurrence to identify high-quality habitat most at risk of recent anthropogenic alteration. Population surveys by biologists are targeting these areas and future management actions may focus on mitigating anthropogenic activities there. While this study focuses on D. r. miaria, this approach can evaluate wetland habitat of other aquatic organisms.

  16. Varying energetic costs of Brent Geese along a continuum from aquatic to agricultural habitats: the importance of habitat-specific energy expenditure

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Clausen, Preben; Fox, Anthony David;

    2013-01-01

    We investigated how habitat-specific differences in behavioural patterns affected Brent Goose energetics along a feeding continuum from natural aquatic to inland agricultural habitats. Time-budgets showed that geese using salt-marshes and inland habitats spent more time flying, being aggressive...... with adapting to different food sources. Combining time-budgets with activity-specific BMR-multiplicators showed that activity-based metabolic rates ranged from 1.7 to 2.7 × BMR within habitats exploited by Brent Geese, and emphasized that aquatic areas represent the energetically least expensive foraging...... habitat for these birds. This is largely the result of habitat-specific variation in time spent flying. These findings underline the importance of measuring habitat-specific behaviour and disturbance when studying avian energetics, and demonstrate the risk of uncritically using allometric relationships...

  17. Habitat split as a cause of local population declines of amphibians with aquatic larvae.

    Science.gov (United States)

    Becker, C Guilherme; Fonseca, Carlos R; Haddad, Célio F B; Prado, Paulo I

    2010-02-01

    Most amphibian species have biphasic life histories and undergo an ontogenetic shift from aquatic to terrestrial habitats. In deforested landscapes, streams and forest fragments are frequently disjunct, jeopardizing the life cycle of forest-associated amphibians with aquatic larvae. We tested the impact of habitat split--defined as human-induced disconnection between habitats used by different life-history stages of a species--on four forest-associated amphibian species in a severely fragmented landscape of the Brazilian Atlantic Forest. We surveyed amphibians in forest fragments with and without streams (referred to as wet and dry fragments, respectively), including the adjacent grass-field matrix. Our comparison of capture rates in dry fragments and nearby streams in the matrix allowed us to evaluate the number of individuals that engaged in high-risk migrations through nonforested habitats. Adult amphibians moved from dry fragments to matrix streams at the beginning of the rainy season, reproduced, and returned at the end of the breeding period. Juveniles of the year moved to dry fragments along with adults. These risky reproductive migrations through nonforested habitats that expose individuals to dehydration, predation, and other hazards may cause population declines in dry fragments. Indeed, capture rates were significantly lower in dry fragments compared with wet fragments. Declining amphibians would strongly benefit from investments in the conservation and restoration of riparian vegetation and corridors linking breeding and nonbreeding areas.

  18. A Method for the Estimation of Detritus Energy Generation in Aquatic Habitats

    OpenAIRE

    (1), A. Palavesam; (2), S. Beena; *(1), G. Immanuel

    2005-01-01

    Considering the amount of oxygen used for oxidation of detritus organic matter, oxycalorific co-efficient and morphometric feature (Area) of the zones as well as the energy consumed by the dominant detritivores, a method was proposed to estimate the detritus energy generation in aquatic habitats. The conversion of organic matter to energy by oxycalorific co-efficient was also counterchecked by the direct calorimetric energy estimates using Semi-Micro bomb-Calorimeter. The difference between d...

  19. Movements of Alpine newts (Mesotriton alpestris) between small aquatic habitats (ruts) during the breeding season

    OpenAIRE

    Kopecky, Oldrich; Vojar, Jiri; Denoël, Mathieu

    2010-01-01

    Many species with complex life cycles, such as caudate amphibians, migrate from terrestrial to aquatic habitats for reproduction. However, movements between reproductive ponds within a breeding season have rarely been studied and are usually considered to be limited. Our aim was to determine whether this pattern occurs frequently in Alpine newts (Mesotriton alpestris) inhabiting complexes of small ruts on muddy forest tracks. We analysed capture-recapture data for individually marked newts as...

  20. Global biodiversity of aquatic ammonia-oxidizing archaea is partitioned by habitat

    Directory of Open Access Journals (Sweden)

    Steven J Biller

    2012-07-01

    Full Text Available Archaea play an important role in nitrification and are, thus, inextricably linked to the global carbon and nitrogen cycles. Since the initial discovery of an ammonia monooxygenase α-subunit (amoA gene associated with an archaeal metagenomic fragment, archaeal amoA sequences have been detected in a wide variety of nitrifying environments. Recent sequencing efforts have revealed extensive diversity of archaeal amoA sequences within different habitats. In this study, we have examined over 8000 amoA sequences from the literature and public databases in an effort to understand the ecological factors influencing the distribution and diversity of ammonia-oxidizing archaea (AOA, with a particular focus on sequences from aquatic habitats. This broad survey provides strong statistical support for the hypothesis that different environments contain distinct clusters of AOA amoA sequences, as surprisingly few sequences are found in more than one habitat type. Within aquatic environments, salinity, depth in the water column, and temperature were significantly correlated with the distribution of sequence types. These findings support the existence of multiple distinct aquatic AOA populations in the environment and suggest some possible selective pressures driving the partitioning of AOA amoA diversity.

  1. Quantifying solar spectral irradiance in aquatic habitats for the assessment of photoenhanced toxicity

    Science.gov (United States)

    Barron, M.G.; Little, E.E.; Calfee, R.; Diamond, S.

    2000-01-01

    The spectra and intensity of solar radiation (solar spectral irradiance [SSI]) was quantified in selected aquatic habitats in the vicinity of an oil field on the California coast. Solar spectral irradiance measurements consisted of spectral scans (280-700 rim) and radiometric measurements of ultraviolet (UV): UVB (280-320 nm) and UVA (320-400 nm). Solar spectral irradiance measurements were taken at the surface and at various depths in two marsh ponds, a shallow wetland, an estuary lagoon, and the intertidal area of a high-energy sandy beach. Daily fluctuation in SSI showed a general parabolic relationship with time; maximum structure-activity relationship (SAR) was observed at approximate solar noon. Solar spectral irradiance measurements taken at 10-cm depth at approximate solar noon in multiple aquatic habitats exhibited only a twofold variation in visible light and UVA and a 4.5-fold variation in UVB. Visible light ranged from 11,000 to 19,000 ??W/cm2, UVA ranged from 460 to 1,100 ??W/cm2, and UVB ranged from 8.4 to 38 ??W/cm2. In each habitat, the attenuation of light intensity with increasing water depth was differentially affected over specific wavelengths of SSI. The study results allowed the development of environmentally realistic light regimes necessary for photoenhanced toxicity studies.

  2. NASDA next-generation aquatic habitat for space shuttle and ISS

    Science.gov (United States)

    Masukawa, M.; Ochiai, T.; Kamigaichi, S.; Uchida, S.; Kono, Y.; Takamatsu, T.; Sakimura, T.

    The National Space Development Agency of Japan (NASDA) has more than 20 years of experience developing aquatic animal experiment facilities. These include the Vestibular Function Experiment Unit (VFEU), Aquatic Animal Experiment Unit (AAEU) and another VFEU for marine fish. Each facility had functions such as life support for up to 15 days, water quality control system, gas exchange by artificial lung, video observation through a window by a crewmember, day/night cycle control, feeding system for medaka (AAEU only), and more. We are now studying the next -generation aquatic animal experiment facility or the Aquatic Habitat (AQH) for both Space Shuttle and Space Station use. AQH will have many new capabilities missing in earlier facilities. The following functions are of particular importance: long-term life support for up to 90 days, multigeneration breeding (for medaka and zebrafish), automatic feeding system adaptable for young of fish and amphibians, water quality control for long-term experiments, air-water interface, a computer-driven specimen-monitoring system housed in the facilities, and a specimen sampling system including eggs. A prototype breeding system and the specimen-monitoring system were designed and tested. The prototype breeding system consists of a closed water loop, two 700ml fish chambers with LED lighting, a small artificial lung, and a nitrification bacteria filter. Medaka adult fish were able to mate and spawn in this small breeding system, and the young could grow to adult fish. The water quality control system also worked successfully. For amphibians, the breeding test using tadpoles of xenopus is also starting. We have many difficult technological problems to resolve, but development of AQH is going well. In this paper, we will introduce the results of the component-level test and the concept of AQH. In the future, many space biological experiments will be conducted, especially in the areas of developmental biology, neurophisiology, and

  3. Aquatic Insects of New York Salt Marsh Associated with Mosquito Larval Habitat and their Potential Utility as Bioindicators

    OpenAIRE

    Rochlin, Ilia; Dempsey, Mary E.; Iwanejko, Tom; Ninivaggi, Dominick V.

    2011-01-01

    The aquatic insect fauna of salt marshes is poorly characterized, with the possible exception of biting Diptera. Aquatic insects play a vital role in salt marsh ecology, and have great potential importance as biological indicators for assessing marsh health. In addition, they may be impacted by measures to control mosquitoes such as changes to the marsh habitat, altered hydrology, or the application of pesticides. Given these concerns, the goals of this study were to conduct the first taxonom...

  4. Effects of Grazing Management and Cattle on Aquatic Habitat Use by the Anuran Pseudopaludicola mystacalis in Agro-Savannah Landscapes

    Science.gov (United States)

    Garey, Michel V.; Rossa-Feres, Denise C.

    2016-01-01

    Because of their strong dependence on the environment, the spatial distribution of pond-breeding amphibians can be greatly influenced by anthropogenic habitat alteration. In some agricultural landscapes in Brazil, the anuran Pseudopaludicola mystacalis appears to be highly influenced by land use. Because adult males and tadpoles of this species are usually found in marshy areas with cattle hoof prints, we hypothesized that P. mystacalis preferentially occupies aquatic habitats with marshy areas that are trampled by cattle. To test our hypothesis, we assessed whether the occurrence of P. mystacalis is associated with the presence of cattle and trampled marshy areas, and which environmental features best explain the spatial distribution and abundance of P. mystacalis. To do so, we sampled 38 aquatic habitats in an area intensely used for livestock in southeastern Brazil. We found that the presence of cattle and trampled marshy areas in aquatic habitats are positively associated to P. mystacalis occurrence. Additionally, the abundance of calling males is better predicted by variables of landscape and local habitat structure. Specifically, the size of trampled marshy areas and the proportion of herbaceous vegetation within the aquatic habitat are positively associated with abundance, while distance to nearest aquatic habitat are negatively associated with abundance of calling males. All three of these variables can be directly or indirectly linked to the presence of cattle or grazing management. Therefore, this work shows evidence that Pseudopaludicola mystacalis is positively influenced by grazing management with cattle, and draws attention to other unknown potential consequences of different land use to fresh water diversity. PMID:27658203

  5. The influence of habitat integrity and physical-chemical water variables on the structure of aquatic and semi-aquatic Heteroptera

    Directory of Open Access Journals (Sweden)

    Karina Dias-Silva

    2010-01-01

    Full Text Available This work aimed to assess the effect of certain physical-chemical variables and the Habitat Integrity Index (HII have on an aquatic and semi-aquatic heteropteran community. We collected in five streams (from 1st to 4th order that differed in habitat integrity, in order to test 1 whether heteropteran richness decreases with the Habitat Integrity Index; and 2 whether richness responds to alterations in water physical-chemical variables, since these influence community structure. In each stream, linear transects of 100 m were demarcated. A total of 1425 specimens from 10 families, 30 genera and 67 morphospecies were collected. Species richness was correlated with the Habitat Integrity Index (HII, showing a positive relationship only for Gerromorpha. This may be due to the fact that streams with greater integrity offer nearby marginal vegetation where prey and shelter can be easily found, representing optimal places for oviposition and hunting. Species adapted to such conditions are more sensitive to alterations in the physical structure of rivers. Significant differences in the composition of Heteroptera and studied infra-orders were also observed, which suggests that the anthropic disturbances over these sites have changed these insect communities. Our results indicate that the alteration in riparian areas can lead to significant changes in Heteroptera composition, even though species richness was not affected. The physical-chemical variables showed no influence on the distribution of species. This result suggests that the environment presented insufficient variation that could cause changes in the investigated community, which implies that factors other than those analyzed here may explain such variation. Three species Rhagovelia trailli (White, 1879, Rhagovelia sp. 4 and Tenagobia incerta (Lundblad, 1928 were considered to be indicators of pristine sites. The results indicate that aquatic and semi-aquatic Heteroptera and more specifically the

  6. Conservation of newt guilds in an agricultural landscape of Belgium: the importance of aquatic and terrestrial habitats

    OpenAIRE

    Denoël, Mathieu; Ficetola, G. Francesco

    2008-01-01

    1. Amphibians are declining worldwide in response to local and global pressures. Pond-breeding species are particularly vulnerable to environmental change because they rely on two components of the landscape: aquatic and terrestrial habitats. Agricultural practices are changing rapidly at world and local scales. As a consequence, farm ponds and their surrounding terrestrial landscapes will probably be affected. 2. This study investigated the main habitat determinants for the occurrence of fou...

  7. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2009-06-01

    Full Text Available Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM that may include the sterile insect technique (SIT. To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS, Geographical Information Systems (GIS and the Global Positioning System (GPS was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6% contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not

  8. Mapping and Monitoring Stream Aquatic Habitat With a Narrow-Beam Green Lidar

    Science.gov (United States)

    McKean, J.; Wright, W.; Kinzel, P.; Isaak, D.

    2006-12-01

    Stream environments are structured by complex biophysical processes that operate across multiple spatial and temporal scales. Disentangling these multiscalar and multicausal relationships is difficult, but fundamental to understanding, managing, and monitoring channel aquatic ecosystems. Standard field wading surveys of stream physical habitat are limited by cost and logistics to relatively small, isolated samples. Traditional remotely sensed surveys, including methods such as photogrammetry and near-infrared lidar, suffer from attenuation by water and do not directly map submerged channel topography. The Experimental Advanced Airborne Research Lidar (EAARL) is a full-waveform lidar with a unique ability to simultaneously map, with relatively high resolution, subaqueous and subaerial topography and the vegetation canopy. We have used the EAARL instrument to investigate two dissimilar stream ecosystems. We mapped 40km of low gradient, meandering, gravel-bed streams in central Idaho that are spawning habitat for threatened Chinook salmon. We are using the continuous three-dimensional channel maps to quantitatively explore how channel features affect the distribution of salmon spawning at multiple spatial scales and how modern stream and floodplain topography is related to post-glacial valley evolution. In contrast, the Platte River in central Nebraska is a wide and shallow, sand-bedded river that provides habitat for migratory water birds, including endangered species such as the whooping crane and least tern. Multi-temporal EAARL data are being used to map and monitor the physical response of the Platte River to habitat improvement projects that include in-channel and riparian vegetation removal and river flow augmentation to limit vegetation encroachment.

  9. Dispersal ability and habitat requirements determine landscape-level genetic patterns in desert aquatic insects.

    Science.gov (United States)

    Phillipsen, Ivan C; Kirk, Emily H; Bogan, Michael T; Mims, Meryl C; Olden, Julian D; Lytle, David A

    2015-01-01

    Species occupying the same geographic range can exhibit remarkably different population structures across the landscape, ranging from highly diversified to panmictic. Given limitations on collecting population-level data for large numbers of species, ecologists seek to identify proximate organismal traits-such as dispersal ability, habitat preference and life history-that are strong predictors of realized population structure. We examined how dispersal ability and habitat structure affect the regional balance of gene flow and genetic drift within three aquatic insects that represent the range of dispersal abilities and habitat requirements observed in desert stream insect communities. For each species, we tested for linear relationships between genetic distances and geographic distances using Euclidean and landscape-based metrics of resistance. We found that the moderate-disperser Mesocapnia arizonensis (Plecoptera: Capniidae) has a strong isolation-by-distance pattern, suggesting migration-drift equilibrium. By contrast, population structure in the flightless Abedus herberti (Hemiptera: Belostomatidae) is influenced by genetic drift, while gene flow is the dominant force in the strong-flying Boreonectes aequinoctialis (Coleoptera: Dytiscidae). The best-fitting landscape model for M. arizonensis was based on Euclidean distance. Analyses also identified a strong spatial scale-dependence, where landscape genetic methods only performed well for species that were intermediate in dispersal ability. Our results highlight the fact that when either gene flow or genetic drift dominates in shaping population structure, no detectable relationship between genetic and geographic distances is expected at certain spatial scales. This study provides insight into how gene flow and drift interact at the regional scale for these insects as well as the organisms that share similar habitats and dispersal abilities.

  10. Biological filter capable of simultaneous nitrification and denitrification for Aquatic Habitat in International Space Station

    Science.gov (United States)

    Uemoto, H.; Shoji, T.; Uchida, S.

    2014-04-01

    The biological filter capable of simultaneous nitrification and denitrification was constructed for aquatic animal experiments in the International Space Station (ISS). The biological filter will be used to remove harmful ammonia excreted from aquatic animals in a closed water circulation system (Aquatic Habitat). The biological filter is a cylindrical tank packed with porous glass beads for nitrification and dual plastic bags for denitrification. The porous beads are supporting media for Nitrosomonas europaea and Nitrobacter winogradskyi. The N. europaea cells and N. winogradskyi cells on the porous beads, oxidize the excreted ammonia to nitrate via nitrite. On the other hand, the dual bag is composed of an outer non-woven fabric bag and an inner non-porous polyethylene film bag. The outer bag is supporting media for Paracoccus pantotrophus. The inner bag, in which 99.5% ethanol is packed, releases the ethanol slowly, since ethanol can permeate through the non-porous polyethylene film. The P. pantotrophus cells on the outer bag reduce the produced nitrate to nitrogen gas by using the released ethanol as an electron donor for denitrification. The biological filter constructed in this study consequently removed the ammonia without accumulating nitrate. Most of the excess ethanol was consumed and did not affect the nitrification activity of the N. europaea cells and N. winogradskyi cells severely. In accordance with the aquatic animal experiments in the ISS, small freshwater fish had been bred in the closed water circulation system equipped with the biological filter for 90 days. Ammonia concentration daily excreted from fish is assumed to be 1.7 mg-N/L in the recirculation water. Under such conditions, the harmful ammonia and nitrite concentrations were kept below 0.1 mg-N/L in the recirculation water. Nitrate and total organic carbon concentrations in the recirculation water were kept below 5 mg-N/L and 3 mg-C/L, respectively. All breeding fish were alive and ate

  11. Biological filter capable of simultaneous nitrification and denitrification for Aquatic Habitat in International Space Station.

    Science.gov (United States)

    Uemoto, H; Shoji, T; Uchida, S

    2014-04-01

    The biological filter capable of simultaneous nitrification and denitrification was constructed for aquatic animal experiments in the International Space Station (ISS). The biological filter will be used to remove harmful ammonia excreted from aquatic animals in a closed water circulation system (Aquatic Habitat). The biological filter is a cylindrical tank packed with porous glass beads for nitrification and dual plastic bags for denitrification. The porous beads are supporting media for Nitrosomonas europaea and Nitrobacter winogradskyi. The N. europaea cells and N. winogradskyi cells on the porous beads, oxidize the excreted ammonia to nitrate via nitrite. On the other hand, the dual bag is composed of an outer non-woven fabric bag and an inner non-porous polyethylene film bag. The outer bag is supporting media for Paracoccus pantotrophus. The inner bag, in which 99.5% ethanol is packed, releases the ethanol slowly, since ethanol can permeate through the non-porous polyethylene film. The P. pantotrophus cells on the outer bag reduce the produced nitrate to nitrogen gas by using the released ethanol as an electron donor for denitrification. The biological filter constructed in this study consequently removed the ammonia without accumulating nitrate. Most of the excess ethanol was consumed and did not affect the nitrification activity of the N. europaea cells and N. winogradskyi cells severely. In accordance with the aquatic animal experiments in the ISS, small freshwater fish had been bred in the closed water circulation system equipped with the biological filter for 90 days. Ammonia concentration daily excreted from fish is assumed to be 1.7 mg-N/L in the recirculation water. Under such conditions, the harmful ammonia and nitrite concentrations were kept below 0.1 mg-N/L in the recirculation water. Nitrate and total organic carbon concentrations in the recirculation water were kept below 5 mg-N/L and 3 mg-C/L, respectively. All breeding fish were alive and ate

  12. Ecological risks of shale oil and gas development to wildlife, aquatic resources and their habitats.

    Science.gov (United States)

    Brittingham, Margaret C; Maloney, Kelly O; Farag, Aïda M; Harper, David D; Bowen, Zachary H

    2014-10-01

    Technological advances in hydraulic fracturing and horizontal drilling have led to the exploration and exploitation of shale oil and gas both nationally and internationally. Extensive development of shale resources has occurred within the United States over the past decade, yet full build out is not expected to occur for years. Moreover, countries across the globe have large shale resources and are beginning to explore extraction of these resources. Extraction of shale resources is a multistep process that includes site identification, well pad and infrastructure development, well drilling, high-volume hydraulic fracturing and production; each with its own propensity to affect associated ecosystems. Some potential effects, for example from well pad, road and pipeline development, will likely be similar to other anthropogenic activities like conventional gas drilling, land clearing, exurban and agricultural development and surface mining (e.g., habitat fragmentation and sedimentation). Therefore, we can use the large body of literature available on the ecological effects of these activities to estimate potential effects from shale development on nearby ecosystems. However, other effects, such as accidental release of wastewaters, are novel to the shale gas extraction process making it harder to predict potential outcomes. Here, we review current knowledge of the effects of high-volume hydraulic fracturing coupled with horizontal drilling on terrestrial and aquatic ecosystems in the contiguous United States, an area that includes 20 shale plays many of which have experienced extensive development over the past decade. We conclude that species and habitats most at risk are ones where there is an extensive overlap between a species range or habitat type and one of the shale plays (leading to high vulnerability) coupled with intrinsic characteristics such as limited range, small population size, specialized habitat requirements, and high sensitivity to disturbance

  13. Ecological risks of shale oil and gas development to wildlife, aquatic resources and their habitats

    Science.gov (United States)

    Brittingham, Margaret C.; Maloney, Kelly O.; Farag, Aida M.; Harper, David D.; Bowen, Zachary H.

    2014-01-01

    Technological advances in hydraulic fracturing and horizontal drilling have led to the exploration and exploitation of shale oil and gas both nationally and internationally. Extensive development of shale resources has occurred within the United States over the past decade, yet full build out is not expected to occur for years. Moreover, countries across the globe have large shale resources and are beginning to explore extraction of these resources. Extraction of shale resources is a multistep process that includes site identification, well pad and infrastructure development, well drilling, high-volume hydraulic fracturing and production; each with its own propensity to affect associated ecosystems. Some potential effects, for example from well pad, road and pipeline development, will likely be similar to other anthropogenic activities like conventional gas drilling, land clearing, exurban and agricultural development and surface mining (e.g., habitat fragmentation and sedimentation). Therefore, we can use the large body of literature available on the ecological effects of these activities to estimate potential effects from shale development on nearby ecosystems. However, other effects, such as accidental release of wastewaters, are novel to the shale gas extraction process making it harder to predict potential outcomes. Here, we review current knowledge of the effects of high-volume hydraulic fracturing coupled with horizontal drilling on terrestrial and aquatic ecosystems in the contiguous United States, an area that includes 20 shale plays many of which have experienced extensive development over the past decade. We conclude that species and habitats most at risk are ones where there is an extensive overlap between a species range or habitat type and one of the shale plays (leading to high vulnerability) coupled with intrinsic characteristics such as limited range, small population size, specialized habitat requirements, and high sensitivity to disturbance

  14. How do we share food? Feeding of four amphibian species from an aquatic habitat in south–western Romania

    Directory of Open Access Journals (Sweden)

    Bogdan, H. V.

    2013-01-01

    Full Text Available The feeding of four amphibian species (Triturus cristatus, Lissotriton vulgaris, Bombina variegata, Pelophylax ridibundus was studied in 2011, in south–western Romania. The diet of the newts was uniform and mostly composed of aquatic preys The diet of the anurans was more diversified, comprising more prey taxa, mostly terrestrial. The trophic niches of the two newt species overlapped highly but differed from those of the anurans. The trophic niches of the anurans differed from one another. The differences among the four species’ diets were determined by the use of different trophic resources, originating from different environments, and by their different sizes. The newts’ diet was less diversified because the aquatic habitat was small and poor in trophic availability. The anurans used the aquatic habitat as a base from where they captured terrestrial preys in the surrounding terrestrial environment.

  15. Aquatic habitat measurement and valuation: imputing social benefits to instream flow levels

    Science.gov (United States)

    Douglas, Aaron J.; Johnson, Richard L.

    1991-01-01

    Instream flow conflicts have been analysed from the perspectives offered by policy oriented applied (physical) science, theories of conflict resolution and negotiation strategy, and psychological analyses of the behavior patterns of the bargaining parties. Economics also offers some useful insights in analysing conflict resolution within the context of these water allocation problems. We attempt to analyse the economics of the bargaining process in conjunction with a discussion of the water allocation process. In particular, we examine in detail the relation between certain habitat estimation techniques, and the socially optimal allocation of non-market resources. The results developed here describe the welfare implications implicit in the contemporary general equilibrium analysis of a competitive market economy. We also review certain currently available techniques for assigning dollar values to the social benefits of instream flow. The limitations of non-market valuation techniques with respect to estimating the benefits provided by instream flows and the aquatic habitat contingent on these flows should not deter resource managers from using economic analysis as a basic tool for settling instream flow conflicts.

  16. Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness

    Directory of Open Access Journals (Sweden)

    Roberto E. Reis

    2011-04-01

    Full Text Available The Neotropical freshwater ichthyofauna has among the highest species richness and density of any vertebrate fauna on Earth, with more than 5,600 species compressed into less than 12% of the world’s land surface area, and less than 0.002% of the world’s total liquid water supply. How have so many species come to co-exist in such a small amount of total habitat space? Here we report results of an aquatic faunal survey of the Fitzcarrald region in southeastern Peru, an area of low-elevation upland (200–500 m above sea level rainforest in the Western Amazon, that straddles the headwaters of four large Amazonian tributaries; the Juruá (Yurúa, Ucayali, Purús, and Madre de Dios rivers. All measures of fish species diversity in this region are high; there is high alpha diversity with many species coexisting in the same locality, high beta diversity with high turnover between habitats, and high gamma diversity with high turnover between adjacent tributary basins. Current data show little species endemism, and no known examples of sympatric sister species, within the Fitzcarrald region, suggesting a lack of localized or recent adaptive divergences. These results support the hypothesis that the fish species of the Fitzcarrald region are relatively ancient, predating the Late Miocene-Pliocene (c. 4 Ma uplift that isolated its several headwater basins. The results also suggest that habitat specialization (phylogenetic niche conservatism and geographic isolation (dispersal limitation have contributed to the maintenance of high species richness in this region of the Amazon Basin.

  17. Evaluating the feasibility of planting aquatic plants for habitat restoration in shallow Mississippi lakes

    Science.gov (United States)

    Planting aquatic plants is a technique used to restore native aquatic plant communities in lakes lacking aquatic plants. However, the feasibility of using this restoration technique in Mississippi lakes has not been evaluated. We conducted two exclosure experiments to evaluate the success of planti...

  18. A Qualitative Evidence of the Breeding Sites of Anopheles arabiensis Patton (Diptera: Culicidae) in and Around Kassala Town, Eastern Sudan.

    Science.gov (United States)

    Hamza, Asma Mahmoud; El Rayah, El Amin

    2016-01-01

    Anopheles arabiensis Patton (Diptera: Culicidae) is considered the most efficient malaria vector in eastern Sudan. This study aims to characterize the breeding sites of An. arabiensis throughout the year in and around Kassala town, eastern Sudan. Diverse larval habitat types were visited and characterized based on the habitat type and chemical composition. Mosquito larvae were found in many diverse habitats. During the rainy season, rain pools and water bodies created by the seasonal Gash River serve as the main breeding sites. In the dry season, irrigation canals, seepage from water pipes, neglected wells, artificial containers, and man-made ditches serve as the main breeding sites. Breeding water showed a pH of 7.9 and a low concentration of the total dissolved salts. The results of this study may be considered in planning and implementing larval control programs in the area. PMID:27547039

  19. Identification of Habitat-Specific Biomes of Aquatic Fungal Communities Using a Comprehensive Nearly Full-Length 18S rRNA Dataset Enriched with Contextual Data.

    Science.gov (United States)

    Panzer, Katrin; Yilmaz, Pelin; Weiß, Michael; Reich, Lothar; Richter, Michael; Wiese, Jutta; Schmaljohann, Rolf; Labes, Antje; Imhoff, Johannes F; Glöckner, Frank Oliver; Reich, Marlis

    2015-01-01

    Molecular diversity surveys have demonstrated that aquatic fungi are highly diverse, and that they play fundamental ecological roles in aquatic systems. Unfortunately, comparative studies of aquatic fungal communities are few and far between, due to the scarcity of adequate datasets. We combined all publicly available fungal 18S ribosomal RNA (rRNA) gene sequences with new sequence data from a marine fungi culture collection. We further enriched this dataset by adding validated contextual data. Specifically, we included data on the habitat type of the samples assigning fungal taxa to ten different habitat categories. This dataset has been created with the intention to serve as a valuable reference dataset for aquatic fungi including a phylogenetic reference tree. The combined data enabled us to infer fungal community patterns in aquatic systems. Pairwise habitat comparisons showed significant phylogenetic differences, indicating that habitat strongly affects fungal community structure. Fungal taxonomic composition differed considerably even on phylum and class level. Freshwater fungal assemblage was most different from all other habitat types and was dominated by basal fungal lineages. For most communities, phylogenetic signals indicated clustering of sequences suggesting that environmental factors were the main drivers of fungal community structure, rather than species competition. Thus, the diversification process of aquatic fungi must be highly clade specific in some cases.The combined data enabled us to infer fungal community patterns in aquatic systems. Pairwise habitat comparisons showed significant phylogenetic differences, indicating that habitat strongly affects fungal community structure. Fungal taxonomic composition differed considerably even on phylum and class level. Freshwater fungal assemblage was most different from all other habitat types and was dominated by basal fungal lineages. For most communities, phylogenetic signals indicated clustering of

  20. CEPF Western Ghats Special Series: Metazoan community composition in tree hole aquatic habitats of Silent Valley National Park and New Amarambalam Reserve Forest of the Western Ghats, India

    OpenAIRE

    Nishadh, K. A.; K.S.A. Das

    2012-01-01

    In a study of the metazoan community composition in tree hole aquatic habitat of a tropical rainforest, Silent Valley National Park, and the adjacent moist deciduous forest, New Amarambalam Reserve Forest, of the Western Ghats, 28 different species were recorded from 150 tree hole aquatic habitats with an average of 3-5 species per tree hole. Most of the recorded organisms (96.8%) belong to Odonata (dragonflies and damselflies), Heteroptera (bugs), Diptera (flies), Coleoptera (beetles) and T...

  1. Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

    Directory of Open Access Journals (Sweden)

    Eliningaya J Kweka

    Full Text Available BACKGROUND: Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. METHODS AND FINDINGS: A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60% and An.arabiensis (18.34%, the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024 and An. arabiensis (P = 0.002 larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001, grass cover (P≤0.001, while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001. The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001 when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002. When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. CONCLUSION: These findings suggest that implementation of effective larval

  2. Identifying malaria vector breeding habitats with remote sensing data and terrain-based landscape indices in Zambia

    Directory of Open Access Journals (Sweden)

    Shiff Clive

    2010-11-01

    Full Text Available Abstract Background Malaria, caused by the parasite Plasmodium falciparum, is a significant source of morbidity and mortality in southern Zambia. In the Mapanza Chiefdom, where transmission is seasonal, Anopheles arabiensis is the dominant malaria vector. The ability to predict larval habitats can help focus control measures. Methods A survey was conducted in March-April 2007, at the end of the rainy season, to identify and map locations of water pooling and the occurrence anopheline larval habitats; this was repeated in October 2007 at the end of the dry season and in March-April 2008 during the next rainy season. Logistic regression and generalized linear mixed modeling were applied to assess the predictive value of terrain-based landscape indices along with LandSat imagery to identify aquatic habitats and, especially, those with anopheline mosquito larvae. Results Approximately two hundred aquatic habitat sites were identified with 69 percent positive for anopheline mosquitoes. Nine species of anopheline mosquitoes were identified, of which, 19% were An. arabiensis. Terrain-based landscape indices combined with LandSat predicted sites with water, sites with anopheline mosquitoes and sites specifically with An. arabiensis. These models were especially successful at ruling out potential locations, but had limited ability in predicting which anopheline species inhabited aquatic sites. Terrain indices derived from 90 meter Shuttle Radar Topography Mission (SRTM digital elevation data (DEM were better at predicting water drainage patterns and characterizing the landscape than those derived from 30 m Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER DEM. Conclusions The low number of aquatic habitats available and the ability to locate the limited number of aquatic habitat locations for surveillance, especially those containing anopheline larvae, suggest that larval control maybe a cost-effective control measure in the fight

  3. Aquatic plant and waterfowl habitat survey, 1988 : Stillwater Wildlife Management Area and vicinity

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Aquatic vegetation surveys were conducted on Stillwater Wildlife Management Area, Canvasback Club, Carson Lake, and several other wetlands in Lahontan Valley,...

  4. Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats.

    Science.gov (United States)

    Wężowicz, K; Turnau, K; Anielska, T; Zhebrak, I; Gołuszka, K; Błaszkowski, J; Rozpądek, P

    2015-12-01

    Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research.

  5. Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats.

    Science.gov (United States)

    Wężowicz, K; Turnau, K; Anielska, T; Zhebrak, I; Gołuszka, K; Błaszkowski, J; Rozpądek, P

    2015-12-01

    Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research. PMID:26585452

  6. Aquatic biological communities and associated habitats at selected sites in the Big Wood River Watershed, south-central Idaho, 2014

    Science.gov (United States)

    MacCoy, Dorene E.; Short, Terry M.

    2016-09-28

    Assessments of streamflow (discharge) parameters, water quality, physical habitat, and biological communities were completed between May and September 2014 as part of a monitoring program in the Big Wood River watershed of south-central Idaho. The sampling was conducted by the U.S. Geological Survey in cooperation with Blaine County, Trout Unlimited, the Nature Conservancy, and the Wood River Land Trust to help identify the status of aquatic resources at selected locations in the watershed. Information in this report provides a basis with which to evaluate and monitor the long-term health of the Big Wood River and its major tributaries. Sampling sites were co-located with existing U.S. Geological Survey streamgaging stations: three on the main stem Big Wood River and four on the North Fork Big Wood River (North Fork), Warm Springs Creek (Warm Sp), Trail Creek (Trail Ck), and East Fork Big Wood River (East Fork) tributaries.The analytical results and quality-assurance information for water quality, physical habitat, and biological community samples collected at study sites during 2 weeks in September 2014 are summarized. Water-quality data include concentrations of major nutrients, suspended sediment, dissolved oxygen, and fecal-coliform bacteria. To assess the potential effects of nutrient enrichment on algal growth, concentrations of periphyton biomass (chlorophyll-a and ash free dry weight) in riffle habitats were determined at each site. Physical habitat parameters include stream channel morphology, habitat volume, instream structure, substrate composition, and riparian vegetative cover. Biological data include taxa richness, abundance, and stream-health indicator metrics for macroinvertebrate and fish communities. Statistical summaries of the water-quality, habitat, and biological data are provided along with discussion of how these findings relate to the health of aquatic resources in the Big Wood River watershed.Seasonal discharge patterns using statistical

  7. Aquatic biological communities and associated habitats at selected sites in the Big Wood River Watershed, south-central Idaho, 2014

    Science.gov (United States)

    MacCoy, Dorene E.; Short, Terry M.

    2016-09-28

    Assessments of streamflow (discharge) parameters, water quality, physical habitat, and biological communities were completed between May and September 2014 as part of a monitoring program in the Big Wood River watershed of south-central Idaho. The sampling was conducted by the U.S. Geological Survey in cooperation with Blaine County, Trout Unlimited, the Nature Conservancy, and the Wood River Land Trust to help identify the status of aquatic resources at selected locations in the watershed. Information in this report provides a basis with which to evaluate and monitor the long-term health of the Big Wood River and its major tributaries. Sampling sites were co-located with existing U.S. Geological Survey streamgaging stations: three on the main stem Big Wood River and four on the North Fork Big Wood River (North Fork), Warm Springs Creek (Warm Sp), Trail Creek (Trail Ck), and East Fork Big Wood River (East Fork) tributaries.The analytical results and quality-assurance information for water quality, physical habitat, and biological community samples collected at study sites during 2 weeks in September 2014 are summarized. Water-quality data include concentrations of major nutrients, suspended sediment, dissolved oxygen, and fecal-coliform bacteria. To assess the potential effects of nutrient enrichment on algal growth, concentrations of periphyton biomass (chlorophyll-a and ash free dry weight) in riffle habitats were determined at each site. Physical habitat parameters include stream channel morphology, habitat volume, instream structure, substrate composition, and riparian vegetative cover. Biological data include taxa richness, abundance, and stream-health indicator metrics for macroinvertebrate and fish communities. Statistical summaries of the water-quality, habitat, and biological data are provided along with discussion of how these findings relate to the health of aquatic resources in the Big Wood River watershed.Seasonal discharge patterns using statistical

  8. Morphological and physico-chemical properties of British aquatic habitats potentially exposed to pesticides.

    OpenAIRE

    Brown, Colin D.; Turner, Nigel; Hollis, John; Bellamy, Patricia H.; Biggs, Jeremy; Williams, Penny; Arnold, Dave; Pepper, Tim; Maund, Steve

    2006-01-01

    Approaches to describe the exposure of non-target aquatic organisms to agricultural pesticides can be limited by insufficient knowledge of the environmental conditions where the compounds are used. This study analysed information from national and regional datasets gathered in the UK describing the morphological and physico-chemical properties of rivers, streams, ponds and ditches. An aggregation approach was adopted, whereby the landscape was divided into 12 hydrogeological classes for agric...

  9. CEPF Western Ghats Special Series: Metazoan community composition in tree hole aquatic habitats of Silent Valley National Park and New Amarambalam Reserve Forest of the Western Ghats, India

    Directory of Open Access Journals (Sweden)

    K.A. Nishadh

    2012-11-01

    Full Text Available In a study of the metazoan community composition in tree hole aquatic habitat of a tropical rainforest, Silent Valley National Park, and the adjacent moist deciduous forest, New Amarambalam Reserve Forest, of the Western Ghats, 28 different species were recorded from 150 tree hole aquatic habitats with an average of 3-5 species per tree hole. Most of the recorded organisms (96.8% belong to Odonata (dragonflies and damselflies, Heteroptera (bugs, Diptera (flies, Coleoptera (beetles and Trichoptera (caddisflies. The study reports the first record of toe-winged beetle larvae (Ptilodactylidae in a tree hole aquatic habitat. The most significant observation is the prolific occurrence of trichopteran larvae as the second most abundant taxa in tree holes of Silent Valley National Park, and this stands as the first comprehensive record of the entire order in the habitat studied. The study upholds the importance of less explored microhabitats in the Western Ghats region in terms of sustaining unique community composition in the most delicate and extreme habitat conditions. It also puts forward important ecological research questions on biodiversity ecosystem functionality which could impart important lessons for managing and conserving the diminishing tropical evergreen forests which are significant for these unique habitats.

  10. Aquatic insects of New York salt marsh associated with mosquito larval habitat and their potential utility as bioindicators.

    Science.gov (United States)

    Rochlin, Ilia; Dempsey, Mary E; Iwanejko, Tom; Ninivaggi, Dominick V

    2011-01-01

    The aquatic insect fauna of salt marshes is poorly characterized, with the possible exception of biting Diptera. Aquatic insects play a vital role in salt marsh ecology, and have great potential importance as biological indicators for assessing marsh health. In addition, they may be impacted by measures to control mosquitoes such as changes to the marsh habitat, altered hydrology, or the application of pesticides. Given these concerns, the goals of this study were to conduct the first taxonomic survey of salt marsh aquatic insects on Long Island, New York, USA and to evaluate their utility for non-target pesticide impacts and environmental biomonitoring. A total of 18 species from 11 families and five orders were collected repeatedly during the five month study period. Diptera was the most diverse order with nine species from four families, followed by Coleoptera with four species from two families, Heteroptera with three species from three families, then Odonata and the hexapod Collembola with one species each. Water boatmen, Trichocorixa verticalis Fieber (Heteroptera: Corixidae) and a shore fly, Ephydra subopaca Loew (Diptera: Ephydridae), were the two most commonly encountered species. An additional six species; Anurida maritima Guérin-Méneville (Collembola: Neanuridae), Mesovelia mulsanti White (Heteroptera: Mesovelidae), Enochrus hamiltoni Horn (Coleoptera: Hydrophilidae), Tropisternus quadristriatus Horn (Coleoptera: Hydrophilidae), Dasyhelea pseudocincta Waugh and Wirth (Diptera: Ceratopogonidae), and Brachydeutera argentata Walker (Diptera: Ephydridae), were found regularly. Together with the less common Erythrodiplax berenice Drury (Odonata: Libellulidae), these nine species were identified as the most suitable candidates for pesticide and environmental impact monitoring due to abundance, position in the food chain, and extended seasonal occurrence. This study represents a first step towards developing an insect-based index of biological integrity for

  11. Larvicidal effects of Chinaberry (Melia azederach) powder on Anopheles arabiensis in Ethiopia

    Science.gov (United States)

    2011-01-01

    Background Synthetic insecticides are employed in the widely-used currently favored malaria control techniques involving indoor residual spraying and treated bednets. These methods have repeatedly proven to be highly effective at reducing malaria incidence and prevalence. However, rapidly emerging mosquito resistance to the chemicals and logistical problems in transporting supplies to remote locations threaten the long-term sustainability of these techniques. Chinaberry (Melia azederach) extracts have been shown to be effective growth-inhibiting larvicides against several insects. Because several active chemicals in the trees' seeds have insecticidal properties, the emergence of resistance is unlikely. Here, we investigate the feasibility of Chinaberry as a locally available, low-cost sustainable insecticide that can aid in controlling malaria. Chinaberry fruits were collected from Asendabo, Ethiopia. The seeds were removed from the fruits, dried and crushed into a powder. From developmental habitats in the same village, Anopheles arabiensis larvae were collected and placed into laboratory containers. Chinaberry seed powder was added to the larval containers at three treatment levels: 5 g m-2, 10 g m-2 and 20 g m-2, with 100 individual larvae in each treatment level and a control. The containers were monitored daily and larvae, pupae and adult mosquitoes were counted. This experimental procedure was replicated three times. Results Chinaberry seed powder caused an inhibition of emergence of 93% at the 5 g m-2 treatment level, and 100% inhibition of emergence at the two higher treatment levels. The Chinaberry had a highly statistically significant larvicidal effect at all treatment levels (χ2 = 184, 184, and 155 for 5 g m-2, 10 g m-2 and 20 g m-2, respectively; p larvicide against the major African malaria vector An. arabiensis. The seed could provide a sustainable additional malaria vector control tool that can be used where the tree is abundant and where An

  12. Integrated assessment of river health based on the conditions of water quality,aquatic life and physical habitat

    Institute of Scientific and Technical Information of China (English)

    MENG Wei; ZHANG Nan; ZHANG Yuan; ZHENG Binghui

    2009-01-01

    The health conditions of Liao River were assessed using 25 sampling sites in April 2005, with water quality index, biotic index and physical habitat quality index.Based on the method of cluster analysis (CA) for water quality indices, it reveals that heavily polluted sites of Liao River are located at estuary and mainstream.The aquatic species surveyed were attached algae and benthic invertebrates.The result shows that the diversity and biomass of attached algae and benthic index of biotic integrity (B-IBI) are degrading as the chemical and physical quality of water bodies deteriorating.Physiochemical parameters, BOD5, CODCr, TN, TP, NH3-N, DO, petroleum hydrocarbon and conductivity, were statistically analyzed with principal component analysis and correlation analysis.The statistical results were incorporated into the integrated assessing water quality index, combining fecal coliform count, attached algae diversity, B-IBI and physical habitat quality score, a comprehensive integrated assessing system of river ecological health was established.Based on the systimetic assesment, the assessed sites are categorized into 9 "healthy" and "sub-healthy" sites and 8 "sub-sick" and "sick" sites.

  13. Estimating fish exploitation and aquatic habitat loss across diffuse inland recreational fisheries.

    Directory of Open Access Journals (Sweden)

    Derrick Tupper de Kerckhove

    Full Text Available The current state of many freshwater fish stocks worldwide is largely unknown but suspected to be vulnerable to exploitation from recreational fisheries and habitat degradation. Both these factors, combined with complex ecological dynamics and the diffuse nature of inland fisheries could lead to an invisible collapse: the drastic decline in fish stocks without great public or management awareness. In this study we provide a method to address the pervasive knowledge gaps in regional rates of exploitation and habitat degradation, and demonstrate its use in one of North America's largest and most diffuse recreational freshwater fisheries (Ontario, Canada. We estimated that (1 fish stocks were highly exploited and in apparent danger of collapse in management zones close to large population centres, and (2 fish habitat was under a low but constant threat of degradation at rates comparable to deforestation in Ontario and throughout Canada. These findings confirm some commonly held, but difficult to quantify, beliefs in inland fisheries management but also provide some further insights including (1 large anthropogenic projects greater than one hectare could contribute much more to fish habitat loss on an area basis than the cumulative effect of smaller projects within one year, (2 hooking mortality from catch-and-release fisheries is likely a greater source of mortality than the harvest itself, and (3 in most northern management zones over 50% of the fisheries resources are not yet accessible to anglers. While this model primarily provides a framework to prioritize management decisions and further targeted stock assessments, we note that our regional estimates of fisheries productivity and exploitation were similar to broadscale monitoring efforts by the Province of Ontario. We discuss the policy implications from our results and extending the model to other jurisdictions and countries.

  14. Global biodiversity of aquatic ammonia-oxidizing archaea is partitioned by habitat

    OpenAIRE

    Biller, Steven J.; Mosier, Annika C.; Wells, George F.; Francis, Christopher A.

    2012-01-01

    Archaea play an important role in nitrification and are, thus, inextricably linked to the global carbon and nitrogen cycles. Since the initial discovery of an ammonia monooxygenase α-subunit (amoA) gene associated with an archaeal metagenomic fragment, archaeal amoA sequences have been detected in a wide variety of nitrifying environments. Recent sequencing efforts have revealed extensive diversity of archaeal amoA sequences within different habitats. In this study, we have examined over 800...

  15. Two mechanisms of aquatic and terrestrial habitat change along an Alaskan Arctic coastline

    Science.gov (United States)

    Arp, Christopher D.; Jones, Benjamin M.; Schmutz, Joel A.; Urban, Frank E.; Jorgenson, M. Torre

    2010-01-01

    Arctic habitats at the interface between land and sea are particularly vulnerable to climate change. The northern Teshekpuk Lake Special Area (N-TLSA), a coastal plain ecosystem along the Beaufort Sea in northern Alaska, provides habitat for migratory waterbirds, caribou, and potentially, denning polar bears. The 60-km coastline of N-TLSA is experiencing increasing rates of coastline erosion and storm surge flooding far inland resulting in lake drainage and conversion of freshwater lakes to estuaries. These physical mechanisms are affecting upland tundra as well. To better understand how these processes are affecting habitat, we analyzed long-term observational records coupled with recent short-term monitoring. Nearly the entire coastline has accelerating rates of erosion ranging from 6 m/year from 1955 to 1979 and most recently peaking at 17 m/year from 2007 to 2009, yet an intensive monitoring site along a higher bluff (3–6 masl) suggested high interannual variability. The frequency and magnitude of storm events appears to be increasing along this coastline and these patterns correspond to a greater number of lake tapping and flooding events since 2000. For the entire N-TLSA, we estimate that 6% of the landscape consists of salt-burned tundra, while 41% is prone to storm surge flooding. This offset may indicate the relative frequency of low-magnitude flood events along the coastal fringe. Monitoring of coastline lakes confirms that moderate westerly storms create extensive flooding, while easterly storms have negligible effects on lakes and low-lying tundra. This study of two interacting physical mechanisms, coastal erosion and storm surge flooding, provides an important example of the complexities and data needs for predicting habitat change and biological responses along Arctic land–ocean interfaces.

  16. Aquatic beetles (Coleoptera in springs of a small lowland river: habitat factors vs. landscape factors

    Directory of Open Access Journals (Sweden)

    Pakulnicka J.

    2016-01-01

    Full Text Available We identified the beetle fauna of springs of a small lowland river and attempted to determine the direction and magnitude of beetle migration between the springs and neighboring water bodies in the river valley, as well as the local environmental factors and landscape parameters that most influence the character of aquatic beetle assemblages in the springs. We studied springs of three limnological types, along the entire length of the river valley, and identified 42 beetle species. All types of springs were dominated by stagnobiontic species, which enter springs from other aquatic environments, mainly via dispersion by air. We also found a small proportion of crenophiles and a substantial proportion of rheophiles and tyrphophiles, which was linked to the close proximity of the river and dystrophic water bodies. The fauna of the springs was affected to a similar degree by local environmental factors and by landscape factors acting on a broader scale. This indicates the need for broader consideration of landscape factors, which are often neglected in ecological studies.

  17. Numerical Model of Channel and Aquatic Habitat Response to Sediment Pulses in Mountain Rivers of Central Idaho

    Science.gov (United States)

    Lewicki, M.; Buffington, J. M.; Thurow, R. F.; Isaak, D. J.

    2006-12-01

    Mountain rivers in central Idaho receive pulsed sediment inputs from a variety of mass wasting processes (side-slope landslides, rockfalls, and tributary debris flows). Tributary debris flows and hyperconcentrated flows are particularly common due to winter "rain-on-snow" events and summer thunderstorms, the effects of which are amplified by frequent wildfire and resultant changes in vegetation, soil characteristics, and basin hydrology. Tributary confluences in the study area are commonly characterized by debris fans built by these repeated sediment pulses, providing long-term controls on channel slope, hydraulics and sediment transport capacity in the mainstem channel network. These long-term impacts are magnified during debris-flow events, which deliver additional sediment and wood debris to the fan and may block the mainstem river. These changes in physical conditions also influence local and downstream habitat for aquatic species, and can impact local human infrastructure (roads, bridges). Here, we conduct numerical simulations using a modified version of Cui's [2005] network routing model to examine bedload transport and debris-fan evolution in medium- sized watersheds (65-570 km2) of south-central Idaho. We test and calibrate the model using data from a series of postfire debris-flow events that occurred from 2003-4. We investigate model sensitivity to different controlling factors (location of the pulse within the stream network, volume of the pulse, and size distribution of the input material). We predict that on decadal time scales, sediment pulses cause a local coarsening of the channel bed in the vicinity of the sediment input, and a wave of downstream fining over several kilometers of the river (as long as the pulse material is not coarser than the stream bed itself). The grain-size distribution of the pulse influences its rate of erosion, the rate and magnitude of downstream fining, and the time required for system recovery. The effects of textural

  18. Fatty acid composition at the base of aquatic food webs is influenced by habitat type and watershed land use.

    Directory of Open Access Journals (Sweden)

    James H Larson

    Full Text Available Spatial variation in food resources strongly influences many aspects of aquatic consumer ecology. Although large-scale controls over spatial variation in many aspects of food resources are well known, others have received little study. Here we investigated variation in the fatty acid (FA composition of seston and primary consumers within (i.e., among habitats and among tributary systems of Lake Michigan, USA. FA composition of food is important because all metazoans require certain FAs for proper growth and development that cannot be produced de novo, including many polyunsaturated fatty acids (PUFAs. Here we sampled three habitat types (river, rivermouth and nearshore zone in 11 tributaries of Lake Michigan to assess the amount of FA in seston and primary consumers of seston. We hypothesize that among-system and among-habitat variation in FAs at the base of food webs would be related to algal production, which in turn is influenced by three land cover characteristics: 1 combined agriculture and urban lands (an indication of anthropogenic nutrient inputs that fuel algal production, 2 the proportion of surface waters (an indication of water residence times that allow algal producers to accumulate and 3 the extent of riparian forested buffers (an indication of stream shading that reduces algal production. Of these three land cover characteristics, only intense land use appeared to strongly related to seston and consumer FA and this effect was only strong in rivermouth and nearshore lake sites. River seston and consumer FA composition was highly variable, but that variation does not appear to be driven by the watershed land cover characteristics investigated here. Whether the spatial variation in FA content at the base of these food webs significantly influences the production of economically important species higher in the food web should be a focus of future research.

  19. Additional selection for insecticide resistance in urban malaria vectors: DDT resistance in Anopheles arabiensis from Bobo-Dioulasso, Burkina Faso.

    Directory of Open Access Journals (Sweden)

    Christopher M Jones

    Full Text Available In the city of Bobo-Dioulasso in Burkina Faso, Anopheles arabiensis has superseded Anopheles gambiae s.s. as the major malaria vector and the larvae are found in highly polluted habitats normally considered unsuitable for Anopheles mosquitoes. Here we show that An. gambiae s.l. adults emerging from a highly polluted site in the city centre (Dioulassoba have a high prevalence of DDT resistance (percentage mortality after exposure to diagnostic dose=65.8% in the dry season and 70.4% in the rainy season, respectively. An investigation into the mechanisms responsible found an unexpectedly high frequency of the 1014S kdr mutation (allele frequency=0.4, which is found at very low frequencies in An. arabiensis in the surrounding rural areas, and an increase in transcript levels of several detoxification genes, notably from the glutathione transferase and cytochrome P450 gene families. A number of ABC transporter genes were also expressed at elevated levels in the DDT resistant An. arabiensis. Unplanned urbanisation provides numerous breeding grounds for mosquitoes. The finding that Anopheles mosquitoes adapted to these urban breeding sites have a high prevalence of insecticide resistance has important implications for our understanding of the selective forces responsible for the rapid spread of insecticide resistant populations of malaria vectors in Africa.

  20. Fishes and aquatic habitats of the Orinoco River Basin: diversity and conservation.

    Science.gov (United States)

    Lasso, C A; Machado-Allison, A; Taphorn, D C

    2016-07-01

    About 1000 freshwater fishes have been found so far in the Orinoco River Basin of Venezuela and Colombia. This high ichthyological diversity reflects the wide range of landscapes and aquatic ecosystems included in the basin. Mountain streams descend from the high Andes to become rapid-flowing foothill rivers that burst out upon vast savannah flatlands where they slowly make their way to the sea. These white-water rivers are heavily laden with sediments from the geologically young Andes. Because their sediment deposits have formed the richest soils of the basin, they have attracted the highest density of human populations, along with the greatest levels of deforestation, wildfires, agricultural biocides and fertilizers, sewage and all the other impacts associated with urban centres, agriculture and cattle ranching. In the southern portion of the basin, human populations are much smaller, where often the only inhabitants are indigenous peoples. The ancient rocks and sands of the Guiana Shield yield clear and black water streams of very different quality. Here, sediment loads are miniscule, pH is very acid and fish biomass is only a fraction of that observed in the rich Andean tributaries to the north. For each region of the basin, the current state of knowledge about fish diversity is assessed, fish sampling density evaluated, the presence of endemic species and economically important species (for human consumption or ornamental purposes) described and gaps in knowledge are pointed out. Current trends in the fishery for human consumption are analysed, noting that stocks of many species are in steep decline, and that current fishing practices are not sustainable. Finally, the major impacts and threats faced by the fishes and aquatic ecosystems of the Orinoco River Basin are summarized, and the creation of bi-national commissions to promote standardized fishing laws in both countries is recommended. PMID:27250805

  1. Aquatic food webs in mangrove and seagrass habitats of Centla Wetland, a Biosphere Reserve in Southeastern Mexico

    Directory of Open Access Journals (Sweden)

    Manuel Mendoza-Carranza

    2010-03-01

    Full Text Available Mangrove and seagrass habitats are important components of tropical coastal zones worldwide, and are conspicuous habitats of Centla Wetland Biosphere Reserve (CWBR in Tabasco, Mexico. In this study, we examine food webs in mangrove- and seagrass-dominated habitats of CWBR using stable isotope ratios of carbon and nitrogen. Our objective was to identify the importance of carbon derived from mangroves and seagrasses to secondary production of aquatic consumers in this poorly studied conservation area. Carbon and nitrogen isotope ratios of basal sources and aquatic consumers indicated that the species-rich food webs of both habitats are dependent on riparian production sources. The abundant Red mangrove Rhizophora mangle appears to be a primary source of carbon for the mangrove creek food web. Even though dense seagrass beds were ubiquitous, most consumers in the lagoon food web appeared to rely on carbon derived from riparian vegetation (e.g. Phragmites australis. The introduced Amazon sailfin catfish Pterygoplichthys pardalis had isotope signatures overlapping with native species (including high-value fisheries species, suggesting potential competition for resources. Future research should examine the role played by terrestrial insects in linking riparian and aquatic food webs, and impacts of the expanding P. pardalis population on ecosystem function and fisheries in CWBR. Our findings can be used as a baseline to reinforce the conservation and management of this important reserve in the face of diverse external and internal human impacts.Manguezais e pradarias de gramíneas são importantes componentes das zonas costeiras tropicais em todo o mundo, sendo habitats comuns nos ''Pântanos de Centla'', uma Reserva da Biosfera localizada em Tabasco, México. Nesse trabalho, são investigadas as teias alimentares de habitats dominados por manguezais e pradarias de gramíneas, através de isótopos estáveis de carbono e nitrogênio, tendo como

  2. Environmental factors associated with larval habitats of anopheline mosquitoes (Diptera: Culicidae in irrigation and major drainage areas in the middle course of the Rift Valley, central Ethiopia

    Directory of Open Access Journals (Sweden)

    Oljira Kenea, Meshesha Balkew & Teshome Gebre-Michael

    2011-06-01

    Full Text Available Background & objectives: Larval control is an integral part of malaria vector management in Ethiopia andelsewhere. For effective larval control, a sound understanding of the factors responsible for spatio-temporalvariation in larval production is essential. A study was thus conducted to characterize larval habitats of anophelinemosquitoes in irrigation and major drainage areas between Adami Tulu and Meki towns, in the middle course ofthe Ethiopian Rift Valley.Methods: Aquatic habitats were sampled for anopheline larvae and the associated environmental variables(water temperature, turbidity, water current, water pH and other variables were measured, characterized andanalyzed.Results: Microscopic identification of the late instars (III and IV of anopheline larvae collected throughout thestudy period yielded nearly 47.6% Anopheles pharoensis, 32.1% An. arabiensis, 17.1% An. squamosus and only3.2% of other species (An. coustani and An. cinereus. Larvae of the local malaria vectors, An. arabiensis andAn. pharoensis were most abundantly sampled from sand pools and natural swamps, respectively. Logisticregression analysis detected four best predictor variables associated with larval abundance of malaria vectorspecies. Thus, relative abundance of An. arabiensis larvae was significantly and inversely associated with aquaticvegetation and water current, whereas the relative abundance of An. pharoensis larvae was significantly andpositively associated with water temperature and the presence of algae in the water bodies.Conclusion: Dry season anopheline larval habitats such as riverine sand pools that are created and maintainedby perennial water bodies and their associated water development projects need to be considered in vectorcontrol operations.

  3. Characterization of water bodies for mosquito habitat using a multi-sensor approach

    Science.gov (United States)

    Midekisa, A.; Wimberly, M. C.; Senay, G. B.

    2012-12-01

    Malaria is a major health problem in Ethiopia. Anopheles arabiensis, which inhabits and breeds in a variety of aquatic habitats, is the major mosquito vector for malaria transmission in the region. In the Amhara region of Ethiopia, mosquito breeding sites are heterogeneously distributed. Therefore, accurate characterization of aquatic habitats and potential breeding sites can be used as a proxy to measure the spatial distribution of malaria risk. Satellite remote sensing provides the ability to map the spatial distribution and monitor the temporal dynamics of surface water. The objective of this study is to map the probability of surface water accumulation to identify potential vector breeding sites for Anopheles arabiensis using remote sensing data from sensors at multiple spatial and temporal resolutions. The normalized difference water index (NDWI), which is based on reflectance in the green and the near infrared (NIR) bands were used to estimate fractional cover of surface water. Temporal changes in surface water were mapped using NDWI indices derived from MODIS surface reflectance product (MOD09A1) for the period 2001-2012. Landsat TM and ETM+ imagery were used to train and calibrate model results from MODIS. Results highlighted interannual variation and seasonal changes in surface water that were observed from the MODIS time series. Static topographic indices that estimate the potential for water accumulation were generated from 30 meter Shuttle Radar Topography Mission (SRTM) elevation data. Integrated fractional surface water cover was developed by combining the static topographic indices and dynamic NDWI indices using Geographic Information System (GIS) overlay methods. Accuracy of the results was evaluated based on ground truth data that was collected on presence and absence of surface water immediately after the rainy season. The study provided a multi-sensor approach for mapping areas with a high potential for surface water accumulation that are

  4. A spatial classification and database for management, research, and policy making: The Great Lakes aquatic habitat framework

    Science.gov (United States)

    Wang, Lizhu; Riseng, Catherine M.; Mason, Lacey; Werhrly, Kevin; Rutherford, Edward; McKenna, James E.; Castiglione, Chris; Johnson, Lucinda B.; Infante, Dana M.; Sowa, Scott P.; Robertson, Mike; Schaeffer, Jeff; Khoury, Mary; Gaiot, John; Hollenhurst, Tom; Brooks, Colin N.; Coscarelli, Mark

    2015-01-01

    Managing the world's largest and most complex freshwater ecosystem, the Laurentian Great Lakes, requires a spatially hierarchical basin-wide database of ecological and socioeconomic information that is comparable across the region. To meet such a need, we developed a spatial classification framework and database — Great Lakes Aquatic Habitat Framework (GLAHF). GLAHF consists of catchments, coastal terrestrial, coastal margin, nearshore, and offshore zones that encompass the entire Great Lakes Basin. The catchments captured in the database as river pour points or coastline segments are attributed with data known to influence physicochemical and biological characteristics of the lakes from the catchments. The coastal terrestrial zone consists of 30-m grid cells attributed with data from the terrestrial region that has direct connection with the lakes. The coastal margin and nearshore zones consist of 30-m grid cells attributed with data describing the coastline conditions, coastal human disturbances, and moderately to highly variable physicochemical and biological characteristics. The offshore zone consists of 1.8-km grid cells attributed with data that are spatially less variable compared with the other aquatic zones. These spatial classification zones and their associated data are nested within lake sub-basins and political boundaries and allow the synthesis of information from grid cells to classification zones, within and among political boundaries, lake sub-basins, Great Lakes, or within the entire Great Lakes Basin. This spatially structured database could help the development of basin-wide management plans, prioritize locations for funding and specific management actions, track protection and restoration progress, and conduct research for science-based decision making.

  5. Effects of water use and land use on streamflow and aquatic habitat in the Sudbury and Assabet River Basins, Massachusetts

    Science.gov (United States)

    Zarriello, Phillip J.; Parker, Gene W.; Armstrong, David S.; Carlson, Carl S.

    2010-01-01

    Water withdrawals from surface-water reservoirs and groundwater have affected streamflow in the Sudbury and Assabet River Basins. These effects are particularly evident in the upper Sudbury River Basin, which prompted the need to improve the understanding of water resources and aquatic habitat in these basins. In 2004, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation, developed a precipitation-runoff model that uses Hydrologic Simulation Program-FORTRAN (HSPF) to evaluate the effects of water use and projected future water-use and land-use change on streamflow. As part of this study, the aquatic habitat in the basins and the effects of streamflow alteration also were evaluated. Chapter 1 of the report covers the development of the HSPF model that focuses on the upper Sudbury River Basin (106 square miles) but covers the entire Sudbury and Assabet River Basins (339 square miles). The model was calibrated to an 11-year period (1993-2003) using observed or estimated streamflow at four streamgages. The model was then used to simulate long-term (1960-2004) streamflows to evaluate the effects of average 1993-2003 water use and projected 2030 water-use and land-use change over long-term climatic conditions. Simulations indicate that the average 1993-2003 withdrawals most altered streamflow relative to no withdrawals in small headwater subbasins where the ratios of mean annual withdrawals to mean annual streamflow are the highest. The effects of withdrawals are also appreciable in other parts of the upper Sudbury River Basin as a result of the perpetuation of the effects of large withdrawals in upstream reaches or in subbasins that also have a high ratio of withdrawal to streamflow. The simulated effects of potential 2030 water-use and land-use change indicate small decreases in flows as a result of increased water demands, but these flow alterations were offset as a result of decreased evapotranspiration

  6. Creating and managing wetland impoundments to provide habitat for aquatic birds

    Science.gov (United States)

    Perry, M.C.; Kangas, P.; Obrecht, H.H.; Comin, Francisco A.; Herrera-Silveira, Jorge A.; Ramirez-Ramirez, Javier

    2000-01-01

    Patuxent Research Refuge, located in Central Maryland (USA), has approximately 140 ha of impoundments that were constructed for recreational and wildlife conservation purposes. Impoundments are of three major designs: dammed ravines, excavated basins, and diked ponds. Over 50 species of wetland plants were transplanted to impoundments of Patuxent from many parts of the United States between 1945 and 1963 to determine the species best suited for establishment in tannin-stained infertile waters. The wood duck was the only waterfowl species commonly observed on the Refuge when the area was established, but Canada geese, mallards, and black ducks, were introduced and numerous techniques developed to improve nesting and brood habitat. Twenty-six waterfowl species and 80 species of other water birds have used the impoundments for resting, feeding, or nesting. Management is now conducted to optimize avian biodiversity. Management techniques include drawdowns of water every 3-5 years in most impoundments to provide maximum plant and invertebrate food resources for wildlife. Research on the impounded wetlands at Patuxent has included evaluation of vegetation in regard to water level management, improving nest box design to reduce use of boxes by starlings, imprinting of waterfowl to elevated nesting structures to reduce predation on nests, and drawdown techniques to increase macroinvertebrates. Data on waterfowl abundance are evaluated relative to management activities and a preliminary computer model for management of the impoundments has been developed. Past, present, and future management and research projects are reviewed in this paper.

  7. RESEARCH: Effects of Recent Volcanic Eruptions on Aquatic Habitat in the Drift River, Alaska, USA: Implications at Other Cook Inlet Region Volcanoes.

    Science.gov (United States)

    DORAVA; MILNER

    1999-02-01

    / Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano. During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano. KEY WORDS: Aquatic habitat; Volcanoes; Lahars; Lahar-runout flows; Macroinvertebrates; Community structure; Community composition

  8. Epidemiological Study on Frequency of Myxosporidian Diseases in Freshwater Fish Stemming from Aquatic Habitats Pertaining to the Danubian Delta Biosphere Reservation

    OpenAIRE

    Laura Daniela Urdeş; Cristiana Diaconescu; Marius Hangan; Marin Monica; Ştefan Diaconescu

    2010-01-01

    order to measure their frequencies and distributions within populations of Esox lucius, Sander lucioperca(Henneguyosis) and Perca fluviatilis (Myxoboliosis) originating from Sontea-Fortuna (S.F.) and Gorgova-Uzlina(G.U.) aquatic habitats, within the Biosphere Reservation of Danubian Delta, Romania.The biologic material was selected without prior knowledge of the disease status. Prevalence was determined byclassifying fishes as either diseased/infected or not, at one moment in time (Point prev...

  9. Assessment of periphyton, aquatic macrophytes, benthic communities, and physical habitat in midwestern United States streams coinciding with varying historical concentrations of atrazine.

    Science.gov (United States)

    Hall, Lenwood W; Anderson, Ronald D; Killen, William D; Hosmer, Alan J; Brain, Richard A

    2014-01-01

    The objectives of this pilot study were to: (1) characterize periphyton and benthic communities using standard collection methods in six Midwest watersheds with varying historical levels of atrazine (low range, medium range and upper range); (2) qualitatively assess presence of aquatic vascular plants at each site; (3) assess and compare physical habitat at each study site in order to evaluate how physical habitat structure may influence the biological communities and (4) analyze the periphyton and benthic macroinvertebrate community data (i.e., series of metrics) among sites to evaluate possible differences or similarities among sites with different historical atrazine exposures. Five of the eight physical habitat metrics (including total physical habitat score) were different among the six study sites. There appeared to be no substantial difference in the structure of periphtyon communities at the six Midwest sites based on 9 of 12 metrics. For the three metrics that showed differences among sites-percentage of sensitive diatoms, percent Achnanches minutissima and percent motile diatoms - there was no consistent pattern with previous degrees of atrazine exposure and the scoring of these metrics. There were also no statistical differences in aquatic macrophyte spatial coverage among the six study areas. Thus, based on the spatially and temporally limited periphyton and aquatic macrophyte data, varying historical atrazine exposure was not associated with impact on resident plant communities (the target receptor group for atrazine). All 10 benthic community metrics showed significant differences among the six Midwest sites. Although no consistent pattern existed with varying historic levels of atrazine, benthic communities at one site with lower historical levels of atrazine were of higher quality than the other five sites. However, this one site also had a higher quality habitat compared to the other sites which was most likely the reason for this benthic condition.

  10. Bacterial and eukaryotic biodiversity patterns in terrestrial and aquatic habitats in the Sør Rondane Mountains, Dronning Maud Land, East Antarctica.

    Science.gov (United States)

    Obbels, Dagmar; Verleyen, Elie; Mano, Marie-José; Namsaraev, Zorigto; Sweetlove, Maxime; Tytgat, Bjorn; Fernandez-Carazo, Rafael; De Wever, Aaike; D'hondt, Sofie; Ertz, Damien; Elster, Josef; Sabbe, Koen; Willems, Anne; Wilmotte, Annick; Vyverman, Wim

    2016-06-01

    The bacterial and microeukaryotic biodiversity were studied using pyrosequencing analysis on a 454 GS FLX+ platform of partial SSU rRNA genes in terrestrial and aquatic habitats of the Sør Rondane Mountains, including soils, on mosses, endolithic communities, cryoconite holes and supraglacial and subglacial meltwater lenses. This inventory was complemented with Denaturing Gradient Gel Electrophoresis targeting Chlorophyta and Cyanobacteria. OTUs belonging to the Rotifera, Chlorophyta, Tardigrada, Ciliophora, Cercozoa, Fungi, Bryophyta, Bacillariophyta, Collembola and Nematoda were present with a relative abundance of at least 0.1% in the eukaryotic communities. Cyanobacteria, Proteobacteria, Bacteroidetes, Acidobacteria, FBP and Actinobacteria were the most abundant bacterial phyla. Multivariate analyses of the pyrosequencing data revealed a general lack of differentiation of both eukaryotes and prokaryotes according to habitat type. However, the bacterial community structure in the aquatic habitats was dominated by the filamentous cyanobacteria Leptolyngbya and appeared to be significantly different compared with those in dry soils, on mosses, and in endolithic habitats. A striking feature in all datasets was the detection of a relatively large amount of sequences new to science, which underscores the need for additional biodiversity assessments in Antarctic inland locations. PMID:26936447

  11. Linking land cover and species distribution models to project potential ranges of malaria vectors: an example using Anopheles arabiensis in Sudan and Upper Egypt

    Directory of Open Access Journals (Sweden)

    Fuller Douglas O

    2012-08-01

    Full Text Available Abstract Background Anopheles arabiensis is a particularly opportunistic feeder and efficient vector of Plasmodium falciparum in Africa and may invade areas outside its normal range, including areas separated by expanses of barren desert. The purpose of this paper is to demonstrate how spatial models can project future irrigated cropland and potential, new suitable habitat for vectors such as An. arabiensis. Methods Two different but complementary spatial models were linked to demonstrate their synergy for assessing re-invasion potential of An. arabiensis into Upper Egypt as a function of irrigated cropland expansion by 2050. The first model (The Land Change Modeler was used to simulate changes in irrigated cropland using a Markov Chain approach, while the second model (MaxEnt uses species occurrence points, land cover and other environmental layers to project probability of species presence. Two basic change scenarios were analysed, one involving a more conservative business-as-usual (BAU assumption and second with a high probability of desert-to-cropland transition (Green Nile to assess a broad range of potential outcomes by 2050. Results The results reveal a difference of 82,000 sq km in potential An. arabiensis range between the BAU and Green Nile scenarios. The BAU scenario revealed a highly fragmented set of small, potential habitat patches separated by relatively large distances (maximum distance = 64.02 km, mean = 12.72 km, SD = 9.92, while the Green Nile scenario produced a landscape characterized by large patches separated by relatively shorter gaps (maximum distance = 49.38, km, mean = 4.51 km, SD = 7.89 that may be bridged by the vector. Conclusions This study provides a first demonstration of how land change and species distribution models may be linked to project potential changes in vector habitat distribution and invasion potential. While gaps between potential habitat patches remained large in the

  12. A unique application of the instream flow incremental methodology (IFIM) to predict impacts on riverine aquatic habitat, resulting from construction of a proposed hydropower reservoir

    International Nuclear Information System (INIS)

    The City of Harrisburg, Pennsylvania, proposed to construct a new low-head hydroelectric project on the Susquehanna River in the central part of the state in 1986, about 108 km upstream of the river mouth. As part of the licensing process, the city was required by the Federal Energy Regulatory Commission to carry out studies that would forecast the impacts on riverine aquatic habitat as a result of construction of the proposed 13 km long by 1.5 km wide reservoir. The methodology selected by the city and its consultants was to use the IFIM to model the habitat conditions in the project reach both before and after construction of the proposed reservoir.The IFIM is usually used to model instream flow releases downstream of dams and diversions, and had not been used before to model habitat conditions within the proposed reservoir area. The study team hydraulically modelled the project reach using existing hydraulic data, and a HEC-2 backwater analysis to determine post-project water surface elevations. The IFG-4 model was used to simulate both pre- and post-project water velocities, by distributing velocities across transects based on known discharges and cell depth. Effects on aquatic habitat were determined using the IFIM PHABSIM program, in which criteria for several evaluation species and life stages were used to yield estimates of Weighted Usable Area. The analysis showed, based on trends in WUA from pre- and post-project conditions, that habitat conditions would improve for several species and life stages, and would be negatively affected for fewer life stages and species. Some agency concerns that construction of the proposed reservoir would have significant adverse effects on the resident and anadromous fish populations were responded to using these results

  13. Malaria in Kakuma refugee camp, Turkana, Kenya: facilitation of Anopheles arabiensis vector populations by installed water distribution and catchment systems

    Directory of Open Access Journals (Sweden)

    Cetron Martin S

    2011-06-01

    Full Text Available Abstract Background Malaria is a major health concern for displaced persons occupying refugee camps in sub-Saharan Africa, yet there is little information on the incidence of infection and nature of transmission in these settings. Kakuma Refugee Camp, located in a dry area of north-western Kenya, has hosted ca. 60,000 to 90,000 refugees since 1992, primarily from Sudan and Somalia. The purpose of this study was to investigate malaria prevalence and attack rate and sources of Anopheles vectors in Kakuma refugee camp, in 2005-2006, after a malaria epidemic was observed by staff at camp clinics. Methods Malaria prevalence and attack rate was estimated from cases of fever presenting to camp clinics and the hospital in August 2005, using rapid diagnostic tests and microscopy of blood smears. Larval habitats of vectors were sampled and mapped. Houses were sampled for adult vectors using the pyrethrum knockdown spray method, and mapped. Vectors were identified to species level and their infection with Plasmodium falciparum determined. Results Prevalence of febrile illness with P. falciparum was highest among the 5 to 17 year olds (62.4% while malaria attack rate was highest among the two to 4 year olds (5.2/1,000/day. Infected individuals were spatially concentrated in three of the 11 residential zones of the camp. The indoor densities of Anopheles arabiensis, the sole malaria vector, were similar during the wet and dry seasons, but were distributed in an aggregated fashion and predominantly in the same zones where malaria attack rates were high. Larval habitats and larval populations were also concentrated in these zones. Larval habitats were man-made pits of water associated with tap-stands installed as the water delivery system to residents with year round availability in the camp. Three percent of A. arabiensis adult females were infected with P. falciparum sporozoites in the rainy season. Conclusions Malaria in Kakuma refugee camp was due mainly

  14. Water quality and immatures of the M and S forms of Anopheles gambiae s.s. and An. arabiensis in a Malian village

    Directory of Open Access Journals (Sweden)

    Touré Yeya T

    2006-04-01

    Full Text Available Abstract Introduction The associations between the immatures of Anopheles gambiae s.s. (Diptera: Culicidae, its M and S forms, and Anopheles arabiensis among and within larval breeding habitats in Banambani, Mali were investigated under varying conditions of water quality and rainfall. The intent was to elucidate on niche partitioning of these taxa. Methods Immatures of An. arabiensis, An. gambiae s.s., and its M and S forms were sampled every alternate day for a month in mid-rainy season from three sampling sites in each of the larval breeding habitats (rock pools, swamp, and puddles. Water quality was characterized by alkalinity, conductivity, dissolved oxygen (D.O., nitrate, orthophosphate, pH, temperature, total dissolved solids (TDS, and turbidity. A type 3 analysis of the GENMOD model was used to examine the associations between the proportional frequencies of young (first and second instar larvae and old (third and fourth instar larvae and pupae or total immatures of species or forms among sampling sites within and among larval breeding habitats during a category of rainfall as influenced by water quality. Results Of the 4,174 immatures sampled, 1,300 were molecularly identified to species and forms. Significant association between the proportional frequencies of young larvae of An. arabiensis, An. gambiae s.s., its M and S forms was found among sampling sites within habitats but not among larval breeding habitats. The proportional frequencies of young larvae of M and S forms varied daily perhaps due to recruitment, mortality, and dispersal within habitats. Conductivity and TDS had significant effects when the proportional frequencies of young larvae of M and S forms among sampling sites within habitats were significantly associated. Alkalinity, D.O., orthophosphate, pH, nitrate, temperature and turbidity had no effects on niche partitioning of species and forms among sampling sites within habitats. Rainfall did not affect the frequencies

  15. Unifying research on the fragmentation of terrestrial and aquatic habitats: patches, connectivity and the matrix in riverscapes

    Science.gov (United States)

    Eros, Tibor; Grant, Evan H. Campbell

    2015-01-01

    While there is an increasing emphasis in terrestrial ecology on determining the influence of the area that surrounds habitat patches (the landscape ‘matrix’) relative to the characteristics of the patches themselves, research on these aspects in running waters is still rather underrepresented.

  16. Diet of Tadpoles of Microhyla Ornata from A Freshwater System in Rosekandy Tea Estate, Cachar, Assam and Significance of Conservation of Aquatic Habitats

    Directory of Open Access Journals (Sweden)

    Mithra Dey

    2015-04-01

    Full Text Available Anuran tadpoles are gregarious in nature and knowledge of food and feeding behavior of the tadpoles is very essential for their successful breeding and survival. Dramatic declines in amphibian populations have been noted since 1980 from all over the world and are thus perceived to be one of the most critical threats to global biodiversity. Microhyla ornata commonly known as Ornamented Pygmy Frog, belongs to Family- Microhylidae and is widespread species occurring throughout South Asian countries like Bangladesh, India, Myanmar, Pakistan, Sri Lanka as well as in Japan. Considering the occurrence of tea plantation in the region and the presence of aquatic bodies in tea estates it is necessary to know the feeding habit of the anuran tadpoles and impact of unavailability of suitable food items which will affect the survival and completion of life cycle of the tadpoles. In the present study it was observed that Microhyla ornata tadpoles feed mainly on various algal (25 genera and detrital material. Hence, it may be concluded that aquatic habitats must be conserved and maintained so that conservation of anurans can be ensured.

  17. Evaluation of Endod (Phytolacca dodecandra: Phytolaccaceae) as a Larvicide Against Anopheles arabiensis, the Principal Vector of Malaria in Ethiopia.

    Science.gov (United States)

    Getachew, Dejene; Balkew, Meshesha; Gebre-Michael, Teshome

    2016-06-01

    Malaria control methods rely mostly on adult mosquito control using insecticide-treated nets and indoor residual spraying with insecticides. Plants such as endod (Phytolacca dodecandra) can potentially be used for the control of mosquito larvae as a supplement to adult control methods. Following the discovery of endod, a molluscicide plant, more than 5 decades ago in Ethiopia, subsequent studies have shown that its potency can further be increased by simple procedures such as aging endod berry powder in water. This study was conducted to evaluate the killing effect of fresh and aged endod solution against 4th-stage larvae of Anopheles arabiensis. Laboratory-reared An. arabiensis larvae exposed to different concentrations of endod preparation using distilled or spring water had 50% lethal concentration (LC50)  =  49.6 ppm and 90% lethal concentration (LC90)  =  234 ppm for fresh and LC50  =  36.4 ppm and LC90  =  115.7 ppm for the aged endod solution in distilled water against the laboratory population. Against field-collected larvae of the same species, aged preparations in habitat water resulted in higher LC50 (472.7 ppm) and LC90 (691 ppm) values, with only a slight improvement over fresh preparations in habitat water (LC50  =  456.2 ppm; LC90  =  896.1 ppm). In general, although aged preparations of endod required lower concentrations than fresh to kill at least 90% of the larvae, these concentrations were much higher (12-70×) than that required for schistosome-transmitting snails. PMID:27280350

  18. New species of Paracalanidae along the west coast of India: Paracalanus arabiensis

    Digital Repository Service at National Institute of Oceanography (India)

    Kesarkar, K.S.; Anil, A.C.

    and 12 respectively. Antenna (Figure 3B): biramous; coxa and basis clearly separate, bearing 1 and 2 setae respectively. Exopod 7-segmented, slightly longer than endopod, segment 1 with 2 setae, segments 2 - 6 with 1 seta each, segment 7 bearing..., dorsal view. Fig. 3. Paracalanus arabiensis sp. nov., female (holotype). (A) Antennule; (B) antenna; (C) mandible; (D) maxillule; (E) maxilla; (F) maxilliped. Fig. 4. Paracalanus arabiensis sp. nov., female. (holotype). (A) Leg 1; (B) leg 2; (C) leg 3...

  19. Large flood on a mountain river subjected to restoration: effects on aquatic habitats, channel morphology and valley infrastructure

    Science.gov (United States)

    Hajdukiewicz, Hanna; Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Radecki-Pawlik, Artur

    2016-04-01

    The Biała River, Polish Carpathians, was considerably modified by channelization and channel incision in the twentieth century. To restore the Biała, establishing an erodible corridor was proposed in two river sections located in its mountain and foothill course. In these sections, longer, unmanaged channel reaches alternate with short, channelized reaches; and channel narrowing and incision increases in the downstream direction. In June 2010 an 80-year flood occurred on the river; and this study aims at determining its effects on physical habitat conditions for river biota, channel morphology, and valley-floor infrastructure. Surveys of 10 pairs of closely located, unmanaged and channelized cross sections, performed in 2009 and in the late summer 2010, allowed us to assess the flood-induced changes to physical habitat conditions. A comparison of channel planforms determined before (2009) and after (2012) the flood provided information on the degree of channel widening as well as changes in the width of particular elements of the river's active zone in eight stretches of the Biała. The impact of the flood on valley-floor infrastructure was confronted with the degree of river widening in unmanaged and channelized river reaches. Before the flood, unmanaged cross sections were typified by finer bed material and greater lateral variability in depth-averaged and near-bed flow velocity than channelized cross sections. The flood tended to equalize habitat conditions in both types of river cross sections, obliterating differences (in particular physical habitat parameters) between channelized and unmanaged channel reaches. River widening mostly reflected an increase in the area of channel bars, whereas the widening of low-flow channels was less pronounced. A comparison of channel planform from 2009 and 2012 indicated that intense channel incision typical of downstream sections limited river widening by the flood. Active channel width increased by half in the unmanaged

  20. Differential mercury transfer in the aquatic food web of a double basined lake associated with selenium and habitat

    Science.gov (United States)

    Arcagni, Marina; Campbell, Linda; Arribére, María A.; Marvin-DiPasquale, Mark; Rizzo, Andrea; Guevara, Sergio Ribeiro

    2013-01-01

    Food web trophodynamics of total mercury (THg) and selenium (Se) were assessed for the double-basined ultraoligotrophic system of Lake Moreno, Patagonia. Each basin has differing proportions of littoral and pelagic habitats, thereby providing an opportunity to assess the importance of habitat (e.g. food web structure or benthic MeHg production) in the transfer of Hg and Se to top trophic fish species. Pelagic plankton, analyzed in three size classes (10–53, 53–200, and > 200 μm), had very high [THg], exceeding 200 μg g− 1 dry weight (DW) in the smallest, and a low ratio of MeHg to THg (0.1 to 3%). In contrast, [THg] in littoral macroinvertebrates showed lower values (0.3 to 1.8 μg g− 1 DW). Juvenile and small fish species feeding upon plankton had higher [THg] (0.2 to 8 μg g− 1 muscle DW) compared to large piscivore fish species (0.1 to 1.6 μg g− 1 muscle DW). Selenium concentrations exhibited a much narrower variation range than THg in the food web, varying from 0.5 to 2.7 μg g− 1 DW. Molar Se:Hg ratios exceeded 1 for the majority of organisms in both basins, with most ratios exceeding 10. Using stable nitrogen isotopes as indicator of trophic level, no significant correlations were found with [THg], [Se] or Se:Hg. The apparent lack of biomagnification trends was attributed to elevated [THg] in plankton in the inorganic form mostly, as well as the possibility of consistent Se supply reducing the biomagnification in the food web of the organic portion of THg.

  1. Preliminary survey of polychlorinated biphenyls (PCBs) in aquatic habitats and Great Blue Herons on the Hanford Site. [Ardea herodias

    Energy Technology Data Exchange (ETDEWEB)

    Riley, R.G.; Bean, R.M.; Fitzner, R.E.; Neitzel, D.A.; Rickard, W.H.

    1986-01-01

    Polychlorinated biphenyls (PCBs), constituents of insulating fluids used in electrical transformers and capacitors, were identified during a preliminary survey of waters, sediments, and fish from five locations on the Hanford Site in southeastern Washington State: Gable Mountain Pond, B Pond, West Pond, White Bluffs Slough on the Columbia River, and a pond on the Wahluke Slope. These aquatic areas are all within the foraging range of great blue herons (Ardea herodias) that nest on the Hanford Site. Of those waters that contained PCBs, concentrations were found to be somewhat over 1 ng/L, but less than 20 ng/L, and equal to or less than concentrations reported for other freshwater regions of the United States. The PCBs in sediments and fish closely resembled the chromatographic profile of Aroclor 1260, a commercial PCB mixture produced in the United States by the Monsanto Company. Concentrations of PCBs detected in the sediments were 10 to 100 times lower than those found in soils and sediments from other areas of the nation. Concentrations of PCBs in fat from Hanford great blue herons ranged from 3.6 to 10.6 ppM, while PCB concentrations in herons from other areas of the Pacific Northwest ranged from 0.6 to 15.6 ppM. Great blue herons at Hanford contained PCB isomer distributions closely matching that of Aroclor 1260; great blue herons from other locations contained isomer distributions indicating the presence of a mixture of aroclors. 21 refs., 13 figs., 8 tabs.

  2. Stream classification of the Apalachicola-Chattahoochee-Flint River System to support modeling of aquatic habitat response to climate change

    Science.gov (United States)

    Elliott, Caroline M.; Jacobson, Robert B.; Freeman, Mary C.

    2014-01-01

    A stream classification and associated datasets were developed for the Apalachicola-Chattahoochee-Flint River Basin to support biological modeling of species response to climate change in the southeastern United States. The U.S. Geological Survey and the Department of the Interior’s National Climate Change and Wildlife Science Center established the Southeast Regional Assessment Project (SERAP) which used downscaled general circulation models to develop landscape-scale assessments of climate change and subsequent effects on land cover, ecosystems, and priority species in the southeastern United States. The SERAP aquatic and hydrologic dynamics modeling efforts involve multiscale watershed hydrology, stream-temperature, and fish-occupancy models, which all are based on the same stream network. Models were developed for the Apalachicola-Chattahoochee-Flint River Basin and subbasins in Alabama, Florida, and Georgia, and for the Upper Roanoke River Basin in Virginia. The stream network was used as the spatial scheme through which information was shared across the various models within SERAP. Because these models operate at different scales, coordinated pair versions of the network were delineated, characterized, and parameterized for coarse- and fine-scale hydrologic and biologic modeling. The stream network used for the SERAP aquatic models was extracted from a 30-meter (m) scale digital elevation model (DEM) using standard topographic analysis of flow accumulation. At the finer scale, reaches were delineated to represent lengths of stream channel with fairly homogenous physical characteristics (mean reach length = 350 m). Every reach in the network is designated with geomorphic attributes including upstream drainage basin area, channel gradient, channel width, valley width, Strahler and Shreve stream order, stream power, and measures of stream confinement. The reach network was aggregated from tributary junction to tributary junction to define segments for the

  3. Differential mercury transfer in the aquatic food web of a double basined lake associated with selenium and habitat

    International Nuclear Information System (INIS)

    Food web trophodynamics of total mercury (THg) and selenium (Se) were assessed for the double-basined ultraoligotrophic system of Lake Moreno, Patagonia. Each basin has differing proportions of littoral and pelagic habitats, thereby providing an opportunity to assess the importance of habitat (e.g. food web structure or benthic MeHg production) in the transfer of Hg and Se to top trophic fish species. Pelagic plankton, analyzed in three size classes (10–53, 53–200, and > 200 μm), had very high [THg], exceeding 200 μg g−1 dry weight (DW) in the smallest, and a low ratio of MeHg to THg (0.1 to 3%). In contrast, [THg] in littoral macroinvertebrates showed lower values (0.3 to 1.8 μg g−1 DW). Juvenile and small fish species feeding upon plankton had higher [THg] (0.2 to 8 μg g−1 muscle DW) compared to large piscivore fish species (0.1 to 1.6 μg g−1 muscle DW). Selenium concentrations exhibited a much narrower variation range than THg in the food web, varying from 0.5 to 2.7 μg g−1 DW. Molar Se:Hg ratios exceeded 1 for the majority of organisms in both basins, with most ratios exceeding 10. Using stable nitrogen isotopes as indicator of trophic level, no significant correlations were found with [THg], [Se] or Se:Hg. The apparent lack of biomagnification trends was attributed to elevated [THg] in plankton in the inorganic form mostly, as well as the possibility of consistent Se supply reducing the biomagnification in the food web of the organic portion of THg. Highlights: • Mercury was studied in the food web of Lake Moreno, Nahuel Huapi National Park. • Mercury trophic transfer was assessed by nitrogen stable isotope (δ15N) analysis. • Selenium was determined showing consistent source in pelagic and littoral organisms. • High mercury concentrations, mostly inorganic, were determined in plankton. • No mercury biomagnification was observed in Lake Moreno food web

  4. Differential mercury transfer in the aquatic food web of a double basined lake associated with selenium and habitat

    Energy Technology Data Exchange (ETDEWEB)

    Arcagni, Marina [Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, CNEA, Av. Bustillo km 9.5, 8400 Bariloche (Argentina); Campbell, Linda [Faculty of Science, Saint Mary' s University, 923 Robie Street, Halifax, Nova Scotia B3H 3C3 (Canada); Arribére, María A. [Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, CNEA, Av. Bustillo km 9.5, 8400 Bariloche (Argentina); Instituto Balseiro, Universidad Nacional de Cuyo and Comisión Nacional de Energía Atómica (Argentina); Marvin-DiPasquale, Mark [U.S. Geological Survey, 345 Middlefield Rd./MS 480, Menlo Park, CA 94025 (United States); Rizzo, Andrea [Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, CNEA, Av. Bustillo km 9.5, 8400 Bariloche (Argentina); CONICET (Argentina); Ribeiro Guevara, Sergio, E-mail: ribeiro@cab.cnea.gov.ar [Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, CNEA, Av. Bustillo km 9.5, 8400 Bariloche (Argentina)

    2013-06-01

    Food web trophodynamics of total mercury (THg) and selenium (Se) were assessed for the double-basined ultraoligotrophic system of Lake Moreno, Patagonia. Each basin has differing proportions of littoral and pelagic habitats, thereby providing an opportunity to assess the importance of habitat (e.g. food web structure or benthic MeHg production) in the transfer of Hg and Se to top trophic fish species. Pelagic plankton, analyzed in three size classes (10–53, 53–200, and > 200 μm), had very high [THg], exceeding 200 μg g{sup −1} dry weight (DW) in the smallest, and a low ratio of MeHg to THg (0.1 to 3%). In contrast, [THg] in littoral macroinvertebrates showed lower values (0.3 to 1.8 μg g{sup −1} DW). Juvenile and small fish species feeding upon plankton had higher [THg] (0.2 to 8 μg g{sup −1} muscle DW) compared to large piscivore fish species (0.1 to 1.6 μg g{sup −1} muscle DW). Selenium concentrations exhibited a much narrower variation range than THg in the food web, varying from 0.5 to 2.7 μg g{sup −1} DW. Molar Se:Hg ratios exceeded 1 for the majority of organisms in both basins, with most ratios exceeding 10. Using stable nitrogen isotopes as indicator of trophic level, no significant correlations were found with [THg], [Se] or Se:Hg. The apparent lack of biomagnification trends was attributed to elevated [THg] in plankton in the inorganic form mostly, as well as the possibility of consistent Se supply reducing the biomagnification in the food web of the organic portion of THg. Highlights: • Mercury was studied in the food web of Lake Moreno, Nahuel Huapi National Park. • Mercury trophic transfer was assessed by nitrogen stable isotope (δ{sup 15}N) analysis. • Selenium was determined showing consistent source in pelagic and littoral organisms. • High mercury concentrations, mostly inorganic, were determined in plankton. • No mercury biomagnification was observed in Lake Moreno food web.

  5. The genetics of inviability and male sterility in hybrids between Anopheles gambiae and An. arabiensis.

    Science.gov (United States)

    Slotman, M; Della Torre, A; Powell, J R

    2004-05-01

    Male hybrids between Anopheles gambiae and An. arabiensis suffer from hybrid sterility, and inviability effects are sometimes present as well. We examined the genetic basis of these reproductive barriers between the two species, using 21 microsatellite markers. Generally, recessive inviability effects were found on the X chromosome of gambiae that are incompatible with at least one factor on each arabiensis autosome. Inviability is complete when the gambiae and arabiensis inviability factors are hemi- or homozygous. Using a QTL mapping approach, regions that contribute to male hybrid sterility were also identified. The X chromosome has a disproportionately large effect on male hybrid sterility. Additionally, several moderate-to-large autosomal QTL were found in both species. The effect of these autosomal QTL is contingent upon the presence of an X chromosome from the other species. Substantial regions of the autosomes do not contribute markedly to male hybrid sterility. Finally, no evidence for epistatic interactions between conspecific sterility loci was found.

  6. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape

    Science.gov (United States)

    Pilliod, David S.; Arkle, Robert S.; Robertson, Jeanne M; Murphy, Melanie; Funk, W. Chris

    2015-01-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900–1930), recent (1981–2010), and future (2071–2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May – September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50–80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

  7. Science for Managing Riverine Ecosystems: Actions for the USGS Identified in the Workshop "Analysis of Flow and Habitat for Instream Aquatic Communities"

    Science.gov (United States)

    Bencala, Kenneth E.; Hamilton, David B.; Petersen, James H.

    2006-01-01

    Federal and state agencies need improved scientific analysis to support riverine ecosystem management. The ability of the USGS to integrate geologic, hydrologic, chemical, geographic, and biological data into new tools and models provides unparalleled opportunities to translate the best riverine science into useful approaches and usable information to address issues faced by river managers. In addition to this capability to provide integrated science, the USGS has a long history of providing long-term and nationwide information about natural resources. The USGS is now in a position to advance its ability to provide the scientific support for the management of riverine ecosystems. To address this need, the USGS held a listening session in Fort Collins, Colorado in April 2006. Goals of the workshop were to: 1) learn about the key resource issues facing DOI, other Federal, and state resource management agencies; 2) discuss new approaches and information needs for addressing these issues; and 3) outline a strategy for the USGS role in supporting riverine ecosystem management. Workshop discussions focused on key components of a USGS strategy: Communications, Synthesis, and Research. The workshop identified 3 priority actions the USGS can initiate now to advance its capabilities to support integrated science for resource managers in partner government agencies and non-governmental organizations: 1) Synthesize the existing science of riverine ecosystem processes to produce broadly applicable conceptual models, 2) Enhance selected ongoing instream flow projects with complementary interdisciplinary studies, and 3) Design a long-term, watershed-scale research program that will substantively reinvent riverine ecosystem science. In addition, topical discussion groups on hydrology, geomorphology, aquatic habitat and populations, and socio-economic analysis and negotiation identified eleven important complementary actions required to advance the state of the science and to

  8. Is the European pond turtle Emys orbicularis strictly aquatic? – Habitats where the turtle lives in central Europe

    OpenAIRE

    Sławomir Mitrus

    2010-01-01

    Based on ecological characteristics and phylogenetic analysis, it is possible to try to reconstruct the evolution of ecological traits in turtles. However, the European pond turtle is treated by different scientists as aquatic or as semi-aquatic species. The importance of terrestrial behaviour for this species is discussed.

  9. Radiation-induced sterility for pupal and adult stages of the malaria moquito Anopheles arabiensis

    OpenAIRE

    Helinski, M.E.H.; Parker, A.G.; Knols, B.G.J.

    2006-01-01

    Background - In the context of the Sterile Insect Technique (SIT), radiation-induced sterility in the malaria mosquito Anopheles arabiensis Patton (Diptera: Culicidae) was studied. Male mosquitoes were exposed to gamma rays in the pupal or adult stage and dose-sterility curves were determined. Methods - Pupae were irradiated shortly before emergence (at 22-26 hrs of age), and adults

  10. The spatial distribution of Anopheles gambiae sensu stricto and An. arabiensis (Diptera: Culicidae in Mali

    Directory of Open Access Journals (Sweden)

    N. Sogoba

    2007-05-01

    Full Text Available Variations in the biology and ecology and the high level of genetic polymorphism of malaria vectors in Africa highlight the value of mapping their spatial distribution to enhance successful implementation of integrated vector management. The objective of this study was to collate data on the relative frequencies of Anopheles gambiae s.s. and An. arabiensis mosquitoes in Mali, to assess their association with climate and environmental covariates, and to produce maps of their spatial distribution. Bayesian geostatistical logistic regression models were fitted to identify environmental determinants of the relative frequencies of An. gambiae s.s. and An. arabiensis species and to produce smooth maps of their geographical distribution. The frequency of An. arabiensis was positively associated with the normalized difference vegetation index, the soil water storage index, the maximum temperature and the distance to water bodies. It was negatively associated with the minimum temperature and rainfall. The predicted map suggests that, in West Africa, An. arabiensis is concentrated in the drier savannah areas, while An. gambiae s.s. prefers the southern savannah and land along the rivers, particularly the inner delta of Niger. Because the insecticide knockdown resistance (kdr gene is reported only in An. gambiae s.s. in Mali, the maps provide valuable information for vector control. They may also be useful for planning future implementation of malaria control by genetically manipulated mosquitoes.

  11. Efficacy of three insect repellents against the malaria vector Anopheles arabiensis.

    Science.gov (United States)

    Govere, J; Durrheim, D N; Baker, L; Hunt, R; Coetzee, M

    2000-12-01

    Three commercial repellents marketed in South Africa: Bio-Skincare (BSC, oils of coconut, jojoba, rapeseed and vitamin E), Mosiguard towelletes with 0.574 g quwenling (p-menthane-3,8-diol, PMD) and the standard deet (15% diethyl-3-methylbenzamide, Tabard lotion), were compared against a laboratory colony of the mosquito Anopheles arabiensis Patton (Diptera: Culicidae), the predominant malaria vector in South Africa. Human forearms were treated with 1.2 g BSC, 0.8 g PMD towelette or 0.5 g deet and exposed to 200 hungry An. arabiensis females for 1 min, at intervals of 1-6 h post-treatment. Tests were conducted by three adult male volunteers (aged 30-45 years, crossover controlled test design for 3 consecutive days), using their left arm for treatment and right arm for untreated control. Biting rates averaged 39-52 bites/min on untreated arms. All three repellents provided complete protection against An. arabiensis for up to 3-4 h post-application; deet and PMD gave 90-100% protection up to 5-6h, but BSC declined to only 52% protection 6h post-treatment. These results are interpreted to show that all three repellent products give satisfactory levels of personal protection against An. arabiensis for 4-5 h, justifying further evaluation in the field. PMID:11129710

  12. Non-parametric methods – Tree and P-CFA – for the ecological evaluation and assessment of suitable aquatic habitats: A contribution to fish psychology

    Directory of Open Access Journals (Sweden)

    Andreas H. Melcher

    2012-09-01

    Full Text Available This study analyses multidimensional spawning habitat suitability of the fish species “Nase” (latin: Chondrostoma nasus. This is the first time non-parametric methods were used to better understand biotic habitat use in theory and practice. In particular, we tested (1 the Decision Tree technique, Chi-squared Automatic Interaction Detectors (CHAID, to identify specific habitat types and (2 Prediction-Configural Frequency Analysis (P-CFA to test for statistical significance. The combination of both non-parametric methods, CHAID and P-CFA, enabled the identification, prediction and interpretation of most typical significant spawning habitats, and we were also able to determine non-typical habitat types, e.g., types in contrast to antitypes. The gradual combination of these two methods underlined three significant habitat types: shaded habitat, fine and coarse substrate habitat depending on high flow velocity. The study affirmed the importance for fish species of shading and riparian vegetation along river banks. In addition, this method provides a weighting of interactions between specific habitat characteristics. The results demonstrate that efficient river restoration requires re-establishing riparian vegetation as well as the open river continuum and hydro-morphological improvements to habitats.

  13. Biochemical basis of permethrin resistance in Anopheles arabiensis from Lower Moshi, north-eastern Tanzania

    Directory of Open Access Journals (Sweden)

    Oxborough Richard M

    2010-07-01

    Full Text Available Abstract Background Development of resistance to different classes of insecticides is a potential threat to malaria control. With the increasing coverage of long-lasting insecticide-treated nets in Tanzania, the continued monitoring of resistance in vector populations is crucial. It may facilitate the development of novel strategies to prevent or minimize the spread of resistance. In this study, metabolic-based mechanisms conferring permethrin (pyrethroid resistance were investigated in Anopheles arabiensis of Lower Moshi, Kilimanjaro region of north-eastern Tanzania. Methods WHO susceptibility test kits were used to detect resistance to permethrin in An. arabiensis. The levels and mechanisms of permethrin resistance were determined using CDC bottle bioassays and microplate (biochemical assays. In bottle bioassays, piperonyl butoxide (PBO and s,s,s-tributyl phosphorotrithioate (DEF were used as synergists to inhibit mixed function oxidases and non-specific esterases respectively. Biochemical assays were carried out in individual mosquitoes to detect any increase in the activity of enzymes typically involved in insecticide metabolism (mixed function oxidases, α- and β-esterases. Results Anopheles arabiensis from the study area was found to be partially resistant to permethrin, giving only 87% mortality in WHO test kits. Resistance ratios at KT50 and KT95 were 4.0 and 4.3 respectively. The permethrin resistance was partially synergized by DEF and by PBO when these were mixed with permethrin in bottle bioassays and was fully synergized when DEF and PBO were used together. The levels of oxidase and β-esterase activity were significantly higher in An. arabiensis from Lower Moshi than in the laboratory susceptible strain. There was no difference in α-esterase activity between the two strains. Conclusion Elevated levels of mixed function oxidases and β-esterases play a role in detoxification of permethrin in the resistant An. arabiensis population

  14. Investigation of oil drilling impacts to aquatic habitat resources: In Situ biological assessment of the photoinduced toxicity of environmental releases of crude oil

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study proposed a biological assessment of a recent crude oil spill for potential impacts to aquatic resources due to petroleum hydrocarbon wastes. The...

  15. 2008 High-Flow Experiment at Glen Canyon Dam-Morphologic Response of Eddy-Deposited Sandbars and Associated Aquatic Backwater Habitats along the Colorado River in Grand Canyon National Park

    Science.gov (United States)

    Grams, Paul E.; Schmidt, John C.; Andersen, Matthew E.

    2010-01-01

    The March 2008 high-flow experiment (HFE) at Glen Canyon Dam resulted in sandbar deposition and sandbar reshaping such that the area and volume of associated backwater aquatic habitat in Grand Canyon National Park was greater following the HFE. Analysis of backwater habitat area and volume for 116 locations at 86 study sites, comparing one month before and one month after the HFE, shows that total habitat area increased by 30 percent to as much as a factor of 3 and that volume increased by 80 percent to as much as a factor of 15. These changes resulted from an increase in the area and elevation of sandbars, which isolate backwaters from the main channel, and the scour of eddy return-current channels along the bank where the habitat occurs. Because of this greater relief on the sandbars, backwaters were present across a broader range of flows following the HFE than before the experiment. Reworking of sandbars during diurnal fluctuating flow operations in the first 6 months following the HFE caused sandbar erosion and a reduction of backwater size and abundance to conditions that were 5 to 14 percent greater than existed before the HFE. In the months following the HFE, erosion of sandbars and deposition in eddy return-current channels caused reductions of backwater area and volume. However, sandbar relief was still greater in October 2008 such that backwaters were present across a broader range of discharges than in February 2008. Topographic analyses of the sandbar and backwater morphologic data collected in this study demonstrate that steady flows are associated with a greater amount of continuously available backwater habitat than fluctuating flows, which result in a greater amount of intermittently available habitat. With the exception of the period immediately following the HFE, backwater habitat in 2008 was greater for steady flows associated with dam operations of relatively lower monthly volume (about 227 m3/s) than steady flows associated with dam operations

  16. Habitat Restoration of a Constructed Ohio River Embayment

    OpenAIRE

    Rennaker, Caleb Michael

    2013-01-01

    Backwater habitats of large rivers provide habitat for aquatic biota and influence important predator-prey interactions in fishes and other aquatic organisms. However, these areas often exhibit turbid conditions and lack habitat complexity. Restoration of lentic habitats through direct habitat manipulations has shown success in prior efforts, but these methods have not been tested in backwater habitats of large rivers. I attempted to create habitat in an Ohio River embayment by establishing f...

  17. Molecular typing of bacteria of the genus Asaia in malaria vector Anopheles arabiensis Patton, 1905

    Directory of Open Access Journals (Sweden)

    S. Epis

    2012-08-01

    Full Text Available The acetic acid bacterium Asaia spp. was successfully detected in Anopheles arabiensis Patton, 1905, one of the major vector of human malaria in Sub-Saharan Africa. A collection of 45 Asaia isolates in cellfree media was established from 20 individuals collected from the field in Burkina Faso. 16S rRNA universal polymerase chain reaction (PCR and specific qPCR, for the detection of Asaia spp. were performed in order to reveal the presence of different bacterial taxa associated with this insect. The isolates were typed by internal transcribed spacer-PCR, BOX-PCR, and randomly amplified polymorphic DNA-PCR, proved the presence of different Asaia in A. arabiensis.

  18. Participation of irradiated Anopheles arabiensis males in swarms following field release in Sudan

    OpenAIRE

    Ageep, Tellal B; Damiens, David; Alsharif, Bashir; Ahmed, Ayman; Salih, Elwaleed HO; Ahmed, Fayez TA; Diabaté, Abdoulaye; Lees, Rosemary S.; Gilles, Jeremie RL; El Sayed, Badria B

    2014-01-01

    Background The success of the sterile insect technique (SIT) depends the release of large numbers of sterile males, which are able to compete for mates with the wild male population within the target area. Unfortunately, the processes of colonisation, mass production and irradiation may reduce the competitiveness of sterile males through genetic selection, loss of natural traits and somatic damage. In this context, the capacity of released sterile Anopheles arabiensis males to survive, disper...

  19. Comparative efficacies of permethrin-, deltamethrin- and alpha-cypermethrin-treated nets, against Anopheles arabiensis and Culex quinquefasciatus in northern Tanzania.

    Science.gov (United States)

    Mosha, F W; Lyimo, I N; Oxborough, R M; Matowo, J; Malima, R; Feston, E; Mndeme, R; Tenu, F; Kulkarni, M; Maxwell, C A; Magesa, S M; Rowland, M W

    2008-06-01

    Mosquito nets treated with permethrin, deltamethrin or alpha-cypermethrin at 25 mg/m(2) were evaluated in experimental huts in an area of rice irrigation near Moshi, in northern Tanzania. The nets were deliberately holed to resemble worn nets. The nets treated with permethrin offered the highest personal protection against Anopheles arabiensis (61.6% reduction in fed mosquitoes) and Culex quinquefasciatus (25.0%). Deltamethrin and alpha-cypermethrin provided lower personal protection against An. arabiensis (46.4% and 45.6%, respectively) and no such protection against Cx. quinquefasciatus. Permethrin performed poorly in terms of mosquito mortality, however, killing only 15.2% of the An. arabiensis and 9.2% of the Cx. quinquefasciatus exposed to the nets treated with this pyrethroid (after correcting for control mortality). The alpha-cypermethrin and deltamethrin performed marginally better, with respective mortalities of 32.8% and 33.0% for An. arabiensis and 19.4% and 18.9% for Cx quinquefasciatus. The poor killing effect of permethrin was confirmed in a second trial where a commercial, long-lasting insecticidal net based on this pyrethroid (Olyset) produced low mortalities in both An. arabiensis (11.8%) and Cx. quinquefasciatus (3.6%). Anopheles arabiensis survivors collected from the verandahs of the experimental huts and tested on 0.75%-permethrin and 0.05%-deltamethrin papers, in World Health Organization susceptibility kits, showed mortalities of 96% and 100%, respectively. The continued use of permethrin-treated nets is recommended for personal protection against An. arabiensis. In control programmes that aim to interrupt transmission of pathogens by mosquitoes and/or manage pyrethroid resistance in such vectors, a combination of a pyrethroid and another insecticide with greater killing effect should be considered.

  20. Comparative susceptibility to Plasmodium falciparum of the molecular forms M and S of Anopheles gambiae and Anopheles arabiensis

    Directory of Open Access Journals (Sweden)

    Boudin Christian

    2011-09-01

    Full Text Available Abstract Background The different taxa belonging to Anopheles gambiae complex display phenotypic differences that may impact their contribution to malaria transmission. More specifically, their susceptibility to infection, resulting from a co-evolution between parasite and vector, might be different. The aim of this study was to compare the susceptibility of M and S molecular forms of Anopheles gambiae and Anopheles arabiensis to infection by Plasmodium falciparum. Methods F3 progenies of Anopheles gambiae s.l. collected in Senegal were infected, using direct membrane feeding, with P. falciparum gametocyte-containing blood sampled on volunteer patients. The presence of oocysts was determined by light microscopy after 7 days, and the presence of sporozoite by ELISA after 14 days. Mosquito species and molecular forms were identified by PCR. Results The oocyst rate was significantly higher in the molecular S form (79.07% than in the M form (57.81%, Fisher's exact test p Anopheles arabiensis (55.38%, Fisher's exact test vs. S group p An. gambiae S form (1.72 ± 0.26 than in the An. gambiae M form (0.64 ± 0.04, p An. arabiensis group (0.58 ± 0.04, vs. S group, p Anopheles arabiensis 50.85%, Fisher's exact test vs. S group p Conclusion Infected in the same experimental conditions, the molecular form S of An. gambiae is more susceptible to infection by P. falciparum than the molecular form M of An. gambiae and An. arabiensis.

  1. Thermal limits of wild and laboratory strains of two African malaria vector species, Anopheles arabiensis and Anopheles funestus

    Directory of Open Access Journals (Sweden)

    Lyons Candice L

    2012-07-01

    Full Text Available Abstract Background Malaria affects large parts of the developing world and is responsible for almost 800,000 deaths annually. As climates change, concerns have arisen as to how this vector-borne disease will be impacted by changing rainfall patterns and warming temperatures. Despite the importance and controversy surrounding the impact of climate change on the potential spread of this disease, little information exists on the tolerances of several of the vector species themselves. Methods Using a ramping protocol (to assess critical thermal limits - CT and plunge protocol (to assess lethal temperature limits - LT information on the thermal tolerance of two of Africa’s important malaria vectors, Anopheles arabiensis and Anopheles funestus was collected. The effects of age, thermal acclimation treatment, sex and strain (laboratory versus wild adults were investigated for CT determinations for each species. The effects of age and sex for adults and life stage (larvae, pupae, adults were investigated for LT determinations. Results In both species, females are more tolerant to low and high temperatures than males; larvae and pupae have higher upper lethal limits than do adults. Thermal acclimation of adults has large effects in some instances but small effects in others. Younger adults tend to be more tolerant of low or high temperatures than older age groups. Long-standing laboratory colonies are sufficiently similar in thermal tolerance to field-collected animals to provide reasonable surrogates when making inferences about wild population responses. Differences between these two vectors in their thermal tolerances, especially in larvae and pupae, are plausibly a consequence of different habitat utilization. Conclusions Limited plasticity is characteristic of the adults of these vector species relative to others examined to date, suggesting limited scope for within-generation change in thermal tolerance. These findings and the greater tolerance

  2. Diversity and habitat preference of aquatic insects along the longitudinal gradient of the Macaé River basin, Rio de Janeiro, Brazil

    OpenAIRE

    Baptista, D.F.; D. F. BUSS; L. F. M. DORVILLÉ; NESSIMIAN J. L.

    2001-01-01

    Diversity and habitat preference of macroinvertebrates were studied in Macaé River basin, Rio de Janeiro State, Brazil, along its longitudinal gradient. We selected stream reaches corresponding to 1st, 2nd, 4th, 5th and 6th orders. A Surber sampler was used to collect four macroinvertebrates samples of each substrate (sand, litter in pool areas, stones, and litter in riffle areas) during the three sampling periods, defined based on the rain regime: April (end of the rainy season), July (dry s...

  3. Aquatic plants

    DEFF Research Database (Denmark)

    Madsen, T. V.; Sand-Jensen, K.

    2006-01-01

    Aquatic fl owering plants form a relatively young plant group on an evolutionary timescale. The group has developed over the past 80 million years from terrestrial fl owering plants that re-colonised the aquatic environment after 60-100 million years on land. The exchange of species between...... terrestrial and aquatic environments continues today and is very intensive along stream banks. In this chapter we describe the physical and chemical barriers to the exchange of plants between land and water....

  4. First report of Metarhizium anisopliae IP 46 pathogenicity in adult Anopheles gambiae s.s. and An. arabiensis (Diptera; Culicidae)

    NARCIS (Netherlands)

    Mnyone, L.L.; Russell, T.L.; Lyimo, I.N.; Lwetoijera, D.W.; Kirby, M.J.; Luz, C.

    2009-01-01

    The entomopathogenic fungus Metarhizium anisopliae isolate IP 46, originating from a soil sample collected in 2001 in the Cerrado of Central Brazil, was tested for its ability to reduce the survival of adult male and female Anopheles gambiae s.s. and An. arabiensis mosquitoes. A 6-h exposure to the

  5. Population genetic structure of Anopheles arabiensis and Anopheles gambiae in a malaria endemic region of southern Tanzania

    NARCIS (Netherlands)

    K.R. Ng'habi; B.G.J. Knols; Y. Lee; H.M. Ferguson; G.C. Lanzaro

    2011-01-01

    Background: Genetic diversity is a key factor that enables adaptation and persistence of natural populations towards environmental conditions. It is influenced by the interaction of a natural population's dynamics and the environment it inhabits. Anopheles gambiae s.s. and Anopheles arabiensis are t

  6. Ammonium sulphate fertiliser increases larval populations of Anopheles arabiensis and culicine mosquitoes in rice fields

    DEFF Research Database (Denmark)

    Mutero, C M; Ng'ang'a, P N; Wekoyela, P;

    2004-01-01

    Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block, and the fertili......Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block......, and the fertiliser and control treatments allocated randomly among the ponds. Student's two-sample unpaired t-test was used to test for the significance of differences between the relative counts of larvae in fertiliser and control treatments. The results showed a significant overall increase in the larval...... populations of An. arabiensis (Pfertiliser. Significantly more fourth instar larvae of An. arabiensis were collected in fertiliser than control plots (Pfertiliser application had...

  7. Screening of selected ethnomedicinal plants from South Africa for larvicidal activity against the mosquito Anopheles arabiensis

    Directory of Open Access Journals (Sweden)

    Maharaj Rajendra

    2012-09-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. Methods Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol (1:1, methanol and purified water of each species investigated. Mortality was evaluated relative to the positive control Temephos (Mostop; Agrivo, an effective emulsifiable concentrate larvicide. Results Preliminary screening of crude extracts revealed substantial variation in toxicity with 24 of the 381 samples displaying 100% larval mortality within the seven day exposure period. Four of the high activity plants were selected and subjected to bioassay guided fractionation. The results of the testing of the fractions generated identified one fraction of the plant, Toddalia asiatica as being very potent against the An. arabiensis larvae. Conclusion The present study has successfully identified a plant with superior larvicidal activity at both the crude and semi pure fractions generated through bio-assay guided fractionation. These results have initiated further research into isolating the active compound and developing a malaria vector control tool.

  8. Larvicidal efficacy of Ethiopian ethnomedicinal plant Juniperus procera essential oil against Afrotropical malaria vector Anopheles arabiensis (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Kaliyaperumal Karunamoorthi; Askual Girmay; Samuel Fekadu

    2014-01-01

    Objective: To screen the essential oil of Juniperus procera (J. procera) (Cupressaceae) for larvicidal activity against late third instar larvae of Anopheles arabiensis (An. arabiensis) Patton, the principle malaria vector in Ethiopia.Methods:the laboratory and semi-field conditions by adopting the World Health Organization standard protocols. The larval mortality was observed for 24 h of post exposure.Results:The essential oil of J. procera has demonstrated varying degrees of larvicidal activity The essential oil of J. procera was evaluated against the larvae of An. arabiensis under against An. arabiensis. The LC50 and LC90 values of J. procera were 14.42 and 24.65 mg/L, respectively under the laboratory conditions, and from this data, a Chi-square value 6.662 was observed to be significant at the P=0.05 level. However, under the semi-field conditions the LC50 and LC90 values of J. procera were 24.51 and 34.21 mg/L, respectively and a Chi-square value 4.615 was significant at the P=0.05 level. The observations clearly showed that larval mortality rate is completely time and dose-dependent as compared with the control.Conclusions:This investigation indicates that J. procera could serve as a potential larvicidal agent against insect vector of diseases, particularly An. arabiensis. However further studies are strongly recommended for the identification of the chemical constituents and the mode of action towards the rational design of alternative promising insecticidal agents in the near future.

  9. Tool use by aquatic animals.

    Science.gov (United States)

    Mann, Janet; Patterson, Eric M

    2013-11-19

    Tool-use research has focused primarily on land-based animals, with less consideration given to aquatic animals and the environmental challenges and conditions they face. Here, we review aquatic tool use and examine the contributing ecological, physiological, cognitive and social factors. Tool use among aquatic animals is rare but taxonomically diverse, occurring in fish, cephalopods, mammals, crabs, urchins and possibly gastropods. While additional research is required, the scarcity of tool use can likely be attributable to the characteristics of aquatic habitats, which are generally not conducive to tool use. Nonetheless, studying tool use by aquatic animals provides insights into the conditions that promote and inhibit tool-use behaviour across biomes. Like land-based tool users, aquatic animals tend to find tools on the substrate and use tools during foraging. However, unlike on land, tool users in water often use other animals (and their products) and water itself as a tool. Among sea otters and dolphins, the two aquatic tool users studied in greatest detail, some individuals specialize in tool use, which is vertically socially transmitted possibly because of their long dependency periods. In all, the contrasts between aquatic- and land-based tool users enlighten our understanding of the adaptive value of tool-use behaviour. PMID:24101631

  10. Aquatic ecology of the Elwha River estuary prior to dam removal: Chapter 7 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Duda, Jeffrey J.; Beirne, Matthew M.; Larsen, Kimberly; Barry, Dwight; Stenberg, Karl; McHenry, Michael L.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    The removal of two long-standing dams on the Elwha River in Washington State will initiate a suite of biological and physical changes to the estuary at the river mouth. Estuaries represent a transition between freshwater and saltwater, have unique assemblages of plants and animals, and are a critical habitat for some salmon species as they migrate to the ocean. This chapter summarizes a number of studies in the Elwha River estuary, and focuses on physical and biological aspects of the ecosystem that are expected to change following dam removal. Included are data sets that summarize (1) water chemistry samples collected over a 16 month period; (2) beach seining activities targeted toward describing the fish assemblage of the estuary and migratory patterns of juvenile salmon; (3) descriptions of the aquatic and terrestrial invertebrate communities in the estuary, which represent an important food source for juvenile fish and are important water quality indicators; and (4) the diet and growth patterns of juvenile Chinook salmon in the lower Elwha River and estuary. These data represent baseline conditions of the ecosystem after nearly a century of changes due to the dams and will be useful in monitoring the changes to the river and estuary following dam removal.

  11. Water quality, sediment characteristics, aquatic habitat, geomorphology, and mussel population status of the Clinch River, Virginia and Tennessee, 2009-2011

    Science.gov (United States)

    Krstolic, Jennifer L.; Johnson, Gregory C.; Ostby, Brett J.K.

    2013-01-01

    Chemical, physical, and biological data were collected during 2009-2011 as part of a study of the Clinch River in Virginia and Tennessee. The data from this study, data-collection methods, and laboratory analytical methods used in the study are documented in this report. The study was conducted to describe the conditions of the Clinch River and to determine if there are measurable differences in chemical, physical, or biological characteristics in a segment of the river where freshwater mussel populations are in decline, have low density, richness, little to no recruitment, and lack endangered species (low-quality reach) compared to a segment of the river where mussel assemblages have relatively high density, richness, evidence of recruitment, and support endangered species (high-quality reach). Five continuous water-quality monitors were installed and operated on the mainstem of the Clinch River and two tributaries. Discrete water-quality sample sets were collected during base-flow and stormflow conditions two sites on the Clinch River and on the Guest River, a tributary to the Clinch River predominantly in the Appalachian Plateaus Physiographic Province. Base-flow water-quality samples were collected in July and August 2011 at 15 sites along the mainstem of the Clinch River. Other analyses included longitudinal sampling along the mainstem of the Clinch River at 10 sites to evaluate bed-sediment chemistry, habitat condition, and mollusk community status. In situ freshwater mussel growth and mortality experiments were conducted with hatchery propogated Villosa iris (rainbow mussels). Tissue from the V. iris as well as tissue from 16 Actinonaias pectorosa mussels were analyzed for trace metals, and V. iris mussel tissue was analyzed for organic compounds. Data collected during this investigation were analyzed by various U.S. Geological Survey or U.S. Fish and Wildlife Service laboratories.

  12. Repellent efficacy of DEET, MyggA, neem (Azedirachta indica) oil and chinaberry (Melia azedarach) oil against Anopheles arabiensis, the principal malaria vector in Ethiopia

    OpenAIRE

    Abiy, Ephrem; Gebre-Michael, Teshome; Balkew, Meshesha; Medhin, Girmay

    2015-01-01

    Background In Ethiopia, Anopheles arabiensis is the main vector responsible for the transmission of malaria in the country and its control mainly involves application of indoor residual spraying (IRS) and use of insecticide-treated bed nets (ITNs). Objective Although the role of repellents for reducing man-vector contact is documented in the literature, the response of An. arabiensis to repellents was not previously evaluated under field conditions in Ethiopia. Method The trial was conducted ...

  13. Islands and Stepping-Stones: Comparative Population Structure of Anopheles gambiae sensu stricto and Anopheles arabiensis in Tanzania and Implications for the Spread of Insecticide Resistance.

    OpenAIRE

    Deodatus Maliti; Hilary Ranson; Stephen Magesa; William Kisinza; Juma Mcha; Khamis Haji; Gerald Killeen; David Weetman

    2014-01-01

    Population genetic structures of the two major malaria vectors Anopheles gambiae s.s. and An. arabiensis, differ markedly across Sub-Saharan Africa, which could reflect differences in historical demographies or in contemporary gene flow. Elucidation of the degree and cause of population structure is important for predicting the spread of genetic traits such as insecticide resistance genes or artificially engineered genes. Here the population genetics of An. gambiae s.s. and An. arabiensis in ...

  14. Efficacy of leaves extract of Calotropis procera Ait. (Asclepiadaceae) in controlling Anopheles arabiensis and Culex quinquefasciatus mosquitoes.

    Science.gov (United States)

    Elimam, Abdalla M; Elmalik, Khitma H; Ali, Faysal S

    2009-10-01

    The present study aimed to investigate, the larvicidal, adult emergence inhibition and oviposition deterrent activity of aqueous leaves extract of Calotropis procera against Anopheles arabiensis and Culex quinquefasciatus as natural mosquito larvicide. The larvicidal activity was monitored against 2nd, 3rd and 4th instar larvae of each mosquito species 24 h post-treatment. Adult emergence inhibition activity was tested by exposing 3rd instar larvae of each mosquito species to different concentrations of extracts (200, 400, 600, 800 and 1000 ppm for An. arabiensis and 100, 200, 300, 400, 500 and 600 ppm for Cx. quinquefasciatus). Probit analysis was used to analyze data from bioassay experiments. The oviposition deterrent activity was tested by using three different concentrations of extracts (1000, 500 and 200 for An. arabiensis, and 1000, 500 and 100 for Cx. quinquefasciatus) that caused high, moderate and low larval mortality in the larvicidal experiment against 3rd instar larvae. It was found that, LC50-LC90 values calculated were 273.53-783.43, 366.44-1018.59 and 454.99-1224.62 ppm for 2nd, 3rd and 4th larval instars, respectively, of An. arabiensis and 187.93-433.51, 218.27-538.27 and 264.85-769.13 ppm for 2nd, 3rd and 4th larval instars, respectively, of Cx. quinquefasciatus. Fifty percent of adult emergence inhibition (EI50) was shown at 277.90 and 183.65 ppm for An. arabiensis and Cx. quinquefasciatus, respectively. The pupal stage was not affected till a concentration of 5000 ppm. The extract showed oviposition deterrence and effective repellence against both mosquito species at different concentrations, with the observation on that maximal eggs were laid in low concentration of extract. These results suggest that the leaves extract of C. procera possess remarkable larvicidal, adult emergence inhibitor, repellent and oviposition deterrent effect against both An. arabiensis and Cx. quinquefasciatus, and might be used as natural biocides for mosquito

  15. Status of insecticide susceptibility in Anopheles arabiensis from Mwea rice irrigation scheme, Central Kenya

    Directory of Open Access Journals (Sweden)

    Vulule John M

    2006-06-01

    Full Text Available Abstract Background Control of the Anopheline mosquito vectors of malaria by use of insecticides has been shown to impact on both morbidity and mortality due to this disease. Evidence of insecticide resistance in different settings necessitates surveillance studies to allow prompt detection of resistance should it arise and thus enable its management. Possible resistance by Anopheles arabiensis mosquitoes from Mwea rice irrigation scheme in Central Kenya to insecticides in the four classes of insecticides approved by WHO for indoor residual spraying was investigated. Methods Susceptibility to DDT (an organochlorine, fenitrothion (an organophosphate, bendiocarb (a carbamate, lambdacyhalothrin and permethrin (both pyrethroids was tested using standard WHO diagnostic bioassay kits. Bioassays were performed on non-blood fed mosquitoes one- to three-day old. Knockdown was recorded every 10 min and mortality 24 h post-exposure was noted. Results Mortality 24 h post-exposure was 100% for all insecticides except for lambdacyhalothrin, which averaged 99.46%. Knockdown rates at 10 min intervals were not significantly different between the Mwea population and the susceptible KISUMU strain of Anopheles gambiae sensu stricto control. The KDT50 and KDT95 values for the Mwea population were either lower than those for the control or higher by factors of no more than 2 for most comparisons and compared well with those of An. gambiae sensu lato categorized as susceptible in other studies. Conclusion These results suggest that the Mwea population of An. arabiensis is susceptible to all the insecticides tested. This implies that vector control measures employing any of these insecticides would not be hampered by resistance.

  16. Radiation-induced sterility for pupal and adult stages of the malaria mosquito Anopheles arabiensis

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2006-05-01

    Full Text Available Abstract Background In the context of the Sterile Insect Technique (SIT, radiation-induced sterility in the malaria mosquito Anopheles arabiensis Patton (Diptera: Culicidae was studied. Male mosquitoes were exposed to gamma rays in the pupal or adult stage and dose-sterility curves were determined. Methods Pupae were irradiated shortly before emergence (at 22–26 hrs of age, and adults Results Irradiation of pupae, for all doses tested, had no effect on adult emergence. Survival curves of males irradiated as pupae or adults were similar or even slightly higher than non-irradiated males. Overall, adults appeared to be slightly more susceptible to irradiation, although no significant differences for individual doses were observed. In the pupal stage, a significant negative correlation was found between insemination and dose, but the correlation-coefficient was associated with less than 25% of the total variation. A review of the literature indicated that An. arabiensis is more radiation resistant than other anopheline mosquitoes. Conclusion The optimal dose for male insects to be released in an SIT programme depends on their level of sterility and competitiveness. The use of semi-sterilizing doses to produce more competitive insects is discussed. The most convenient developmental stage for mosquito irradiation on a mass-scale are pupae, but pupal irradiation resulted in a lower insemination rate at the highest dose compared to adult irradiation. On the basis of this study, a suitable dose range that includes semi-sterilizing doses is identified to initiate competitiveness experiments for males irradiated at both developmental stages.

  17. Participation of irradiated Anopheles arabiensis males in swarms following field release in Sudan

    International Nuclear Information System (INIS)

    BACKGROUND: The success of the SIT depends on the; release of large numbers of sterile males, which are able to; compete for mates with the wild male population within the; target area. The processes of colonisation, mass production; and irradiation may reduce the competitiveness of sterile; males through genetic selection, loss of natural traits and; somatic damage. In this context, the capacity of released; sterile Anopheles arabiensis males to survive, disperse and; participate in swarms occurring at varying distances from; the release site was studied using mark-release-recapture; techniques.; METHODS: In order to assess their participation in; swarms, irradiated and marked laboratory-reared male; mosquitoes were released 50, 100 or 200 m from the; known site of a large swarm on three consecutive nights.; Males were collected from this large swarm on subsequent; nights. Over the three days a total of 8,100 males were released.; Mean distance travelled (MDT), daily probability of; survival and estimated population size were calculated; from the recapture data. An effect of male age at the time; of release on these parameters was observed.; RESULTS: Five per cent of the males released over three; days were recaptured. In two-, three- and four-day-old; males, MDT was 118, 178 and 170 m, and the daily survival; probability 0.95, 0.90 and 0.75, respectively. From the; recapture data on the first day following each release, the; Lincoln index gives an estimation of 32,546 males in the; natural population.; DISCUSSION: Sterile An. arabiensis males released into; the field were able to find and participate in existing; swarms, and possibly even initiate swarms. The survival; probability decreased with the age of male on release but; the swarm participation and the distance travelled by older; males seemed higher than for younger males. The inclusion; of a pre-release period may thus be beneficial to male competitiveness; and increase the attractiveness of adult sexing

  18. The role of macrophytes in habitat structuring in aquatic ecosystems: methods of measurement, causes and consequences on animal assemblages' composition and biodiversity O papel das macrófitas na estruturação de habitat em ambientes aquáticos: métodos de medida, causas e consequências para a composição das assembléias animais e biodiversidade

    Directory of Open Access Journals (Sweden)

    Sidinei Magela Thomaz

    2010-06-01

    Full Text Available Aquatic macrophytes play an important role in structuring communities in aquatic environments. These plants provide physical structure, increase habitat complexity and heterogeneity and affect various organisms like invertebrates, fishes and waterbirds. The complexity provided by macrophytes has been exhaustively studied in aquatic environments. However, macrophyte complexity has rarely been measured in a standardized fashion, making comparisons among different studies and the establishment of general conclusions difficult. To address this issue, this review is focused on questions related to the habitat structural complexity provided by these plants, exploring: i how complexity has been viewed by ecologists, with an emphasis on macrophyte studies; ii the pros and cons of several methods used to quantify plant complexity; iii the consequences of habitat structuring by macrophytes on invertebrates and fish and possible causes, mediated by habitat complexity, that lead to changes in these animal assemblages; iv potential impacts of non-native macrophyte species on habitat complexity and v the importance of complexity provided by macrophytes to management strategies for maintaining aquatic biodiversity. We examined literature produced in both temperate and tropical regions, but prioritized the latter. We found a great variety of habitat complexity measurements that are applied to aquatic macrophytes to understand their influence on attached animal assemblages. A lack of standardization (considering the wide range of techniques and scales of resolution used limits comparisons between different studies exploring this subject, in which biological samples and physical substrates were used to explore these relationships. Macrophytes affect animal assemblages and promote biodiversity through a chain of mechanisms, related to habitat complexity, that involve the availability of shelter and feeding sites. Invasive macrophyte species may modify habitat

  19. Fox Island Division habitat rehabilitation and enhancement project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goal of this Habitat Rehabilitation and Enhancement Project (HREP) is to rehabilitate and enhance aquatic and related floodplain habitat. The purpose of this...

  20. Identification of field caught Anopheles gambiae s.s. and Anopheles arabiensis by TaqMan single nucleotide polymorphism genotyping

    Directory of Open Access Journals (Sweden)

    Bayoh Nabie M

    2007-02-01

    Full Text Available Abstract Background Identification of Anopheles gambiae s.s. and Anopheles arabiensis from field-collected Anopheles gambiae s.l. is often necessary in basic and applied research, and in operational control programmes. The currently accepted method involves use of standard polymerase chain reaction amplification of ribosomal DNA (rDNA from the 3' 28S to 5' intergenic spacer region of the genome, and visual confirmation of amplicons of predicted size on agarose gels, after electrophoresis. This report describes development and evaluation of an automated, quantitative PCR method based upon TaqMan™ single nucleotide polymorphism (SNP genotyping. Methods Standard PCR, and TaqMan SNP genotyping with newly designed primers and fluorophore-labeled probes hybridizing to sequences of complementary rDNA specific for either An. gambiae s.s. or An. arabiensis, were conducted in three experiments involving field-collected An. gambiae s.l. from western Kenya, and defined laboratory strains. DNA extraction was from a single leg, sonicated for five minutes in buffer in wells of 96-well PCR plates. Results TaqMan SNP genotyping showed a reaction success rate, sensitivity, and species specificity comparable to that of standard PCR. In an extensive field study, only 29 of 3,041 (0.95% were determined to be hybrids by TaqMan (i.e., having rDNA sequences from both species, however, all but one were An. arabiensis by standard PCR, suggesting an acceptably low (ca. 1% error rate for TaqMan genotyping in mistakenly identifying species hybrids. Conclusion TaqMan SNP genotyping proved to be a sensitive and rapid method for identification of An. gambiae s.l. and An. arabiensis, with a high success rate, specific results, and congruence with the standard PCR method.

  1. Aquatic Sediments.

    Science.gov (United States)

    Sanville, W. D.; And Others

    1978-01-01

    Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

  2. The Genetic Basis of Host Preference and Resting Behavior in the Major African Malaria Vector, Anopheles arabiensis

    Science.gov (United States)

    Main, Bradley J; Lee, Yoosook; Ferguson, Heather M.; Kreppel, Katharina S.; Kihonda, Anicet; Govella, Nicodem J.; Collier, Travis C.; Cornel, Anthony J.; Eskin, Eleazar; Kang, Eun Yong; Nieman, Catelyn C.; Weakley, Allison M.; Lanzaro, Gregory C.

    2016-01-01

    Malaria transmission is dependent on the propensity of Anopheles mosquitoes to bite humans (anthropophily) instead of other dead end hosts. Recent increases in the usage of Long Lasting Insecticide Treated Nets (LLINs) in Africa have been associated with reductions in highly anthropophilic and endophilic vectors such as Anopheles gambiae s.s., leaving species with a broader host range, such as Anopheles arabiensis, as the most prominent remaining source of transmission in many settings. An. arabiensis appears to be more of a generalist in terms of its host choice and resting behavior, which may be due to phenotypic plasticity and/or segregating allelic variation. To investigate the genetic basis of host choice and resting behavior in An. arabiensis we sequenced the genomes of 23 human-fed and 25 cattle-fed mosquitoes collected both in-doors and out-doors in the Kilombero Valley, Tanzania. We identified a total of 4,820,851 SNPs, which were used to conduct the first genome-wide estimates of “SNP heritability” for host choice and resting behavior in this species. A genetic component was detected for host choice (human vs cow fed; permuted P = 0.002), but there was no evidence of a genetic component for resting behavior (indoors versus outside; permuted P = 0.465). A principal component analysis (PCA) segregated individuals based on genomic variation into three groups which were characterized by differences at the 2Rb and/or 3Ra paracentromeric chromosome inversions. There was a non-random distribution of cattle-fed mosquitoes between the PCA clusters, suggesting that alleles linked to the 2Rb and/or 3Ra inversions may influence host choice. Using a novel inversion genotyping assay, we detected a significant enrichment of the standard arrangement (non-inverted) of 3Ra among cattle-fed mosquitoes (N = 129) versus all non-cattle-fed individuals (N = 234; χ2, p = 0.007). Thus, tracking the frequency of the 3Ra in An. arabiensis populations may be of use to infer

  3. Production in aquatic macrophyte communities

    DEFF Research Database (Denmark)

    Binzer, Thomas; Sand-Jensen, Kaj

    2002-01-01

    -dimensional structure because of the strong drag and shear forces of moving water. This difference in canopy structure has been suggested to account for the three- to fivefold higher gross production rates in terrestrial than aquatic communities. To evaluate the effect of community structure in aquatic habitats, we...... combined a simple mechanistic model and empirical measurements on artificially structured macroalgal communities (Ulva lactuca) with varying thallus absorptance and community density. Predicted and measured values corresponded closely and revealed that gross production in high-light environments...... was markedly enhanced by a vertical orientation of thalli when absorptance and community density were both high. This result implies that aquatic macrophytes of high thallus absorptance and community density exposed to high light are limited in attaining high gross production rates because of their inability...

  4. Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration

    Directory of Open Access Journals (Sweden)

    Dongkyun IM

    2011-12-01

    Full Text Available River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.

  5. Islands and stepping-stones: comparative population structure of Anopheles gambiae sensu stricto and Anopheles arabiensis in Tanzania and implications for the spread of insecticide resistance.

    Directory of Open Access Journals (Sweden)

    Deodatus Maliti

    Full Text Available Population genetic structures of the two major malaria vectors Anopheles gambiae s.s. and An. arabiensis, differ markedly across Sub-Saharan Africa, which could reflect differences in historical demographies or in contemporary gene flow. Elucidation of the degree and cause of population structure is important for predicting the spread of genetic traits such as insecticide resistance genes or artificially engineered genes. Here the population genetics of An. gambiae s.s. and An. arabiensis in the central, eastern and island regions of Tanzania were compared. Microsatellite markers were screened in 33 collections of female An. gambiae s.l., originating from 22 geographical locations, four of which were sampled in two or three years between 2008 and 2010. An. gambiae were sampled from six sites, An. arabiensis from 14 sites, and both species from two sites, with an additional colonised insectary sample of each species. Frequencies of the knock-down resistance (kdr alleles 1014S and 1014F were also determined. An. gambiae exhibited relatively high genetic differentiation (average pairwise FST = 0.131, significant even between nearby samples, but without clear geographical patterning. In contrast, An. arabiensis exhibited limited differentiation (average FST = 0.015, but strong isolation-by-distance (Mantel test r = 0.46, p = 0.0008. Most time-series samples of An. arabiensis were homogeneous, suggesting general temporal stability of the genetic structure. An. gambiae populations from Dar es Salaam and Bagamoyo were found to have high frequencies of kdr 1014S (around 70%, with almost 50% homozygote but was at much lower frequency on Unguja Island, with no. An. gambiae population genetic differentiation was consistent with an island model of genetic structuring with highly restricted gene flow, contrary to An. arabiensis which was consistent with a stepping-stone model of extensive, but geographically-restricted gene flow.

  6. Coastal Maine Submerged Aquatic Vegetation Data 1993-1997 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Maine's eelgrass (SAV) meadows form an important aquatic habitat for the state. These meadows provide shelter for juvenile fish, and invertebrates. In certain...

  7. Coastal Maine Submerged Aquatic Vegetation Data 1993-1997 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Maine's eelgrass (SAV) meadows form an important aquatic habitat for the state. These meadows provide shelter for juvenile fish, and invertebrates. In certain...

  8. A resting box for outdoor sampling of adult Anopheles arabiensis in rice irrigation schemes of lower Moshi, northern Tanzania

    Directory of Open Access Journals (Sweden)

    Msangi Shandala

    2009-04-01

    Full Text Available Abstract Background Malaria vector sampling is the best method for understanding the vector dynamics and infectivity; thus, disease transmission seasonality can be established. There is a need to protecting humans involved in the sampling of disease vectors during surveillance or in control programmes. In this study, human landing catch, two cow odour baited resting boxes and an unbaited resting box were evaluated as vector sampling tools in an area with a high proportion of Anopheles arabiensis, as the major malaria vector. Methods Three resting boxes were evaluated against human landing catch. Two were baited with cow odour, while the third was unbaited. The inner parts of the boxes were covered with black cloth materials. Experiments were arranged in latin-square design. Boxes were set in the evening and left undisturbed; mosquitoes were collected at 06:00 am the next morning, while human landing catch was done overnight. Results A total of 9,558 An. arabiensis mosquitoes were collected. 17.5% (N = 1668 were collected in resting box baited with cow body odour, 42.5% (N = 4060 in resting box baited with cow urine, 15.1% (N = 1444 in unbaited resting box and 24.9% (N = 2386 were collected by human landing catch technique. In analysis, the house positions had no effect on the density of mosquitoes caught (DF = 3, F = 0.753, P = 0.387; the sampling technique had significant impact on the caught mosquitoes densities (DF = 3, F 37. 944, P Conclusion Odour-baited resting boxes have shown the possibility of replacing the existing traditional method (human landing catch for sampling malaria vectors in areas with a high proportion of An. arabiensis as malaria vectors. Further evaluations of fermented urine and longevity of the urine odour still need to be investigated.

  9. Identification and expression profiling of putative odorant-binding proteins in the malaria mosquitoes, Anopheles gambiae and A.arabiensis

    Institute of Scientific and Technical Information of China (English)

    LI Zhengxi; Jing-Jiang ZHOU; SHEN Zuorui; Lin FIELD

    2004-01-01

    Olfaction plays a major role in host-seeking behaviour of mosquitoes. An informatics-based genome-wide analysis of odorant-binding protein (OBP) homologues is undertaken,and 32 putative OBP genes in total in the whole genome sequences of Anopheles gambiae are identified. Tissue-specific expression patterns of all A. gambiae OBP candidates are determined by semi-quantitative Reverse Transcription (RT)-PCR using mosquito actin gene as internal expression control standard. The results showed that 20 OBP candidates had strong expression in mosquito olfactory tissues (female antennae), which indicate that OBPs may play an important role in regulating mosquito olfactory behaviours. Species-specific expression patterns of all putative anopheline OBPs are also studied in two of the most important malaria vectors in A. gambiae complex, i.e.A. gambiae and A. arabiensis, which found 12 of the putative OBP genes examined displayed species-differential expression patterns. The cumulative relative expression intensity of the OBPs in A. arabiensis antennae was higher than that in A. gambiae (the ratio is 1441.45:1314.12), which might be due to their different host preference behaviour. While A.gambiae is a highly anthropophilic mosquito, A. arabiensis is more opportunistic (varying from anthropophilic to zoophilic). So the latter should need more OBPs to support its host selection preference. Identification of mosquito OBPs and verification of their tissue- and species-specific expression patterns represent the first step towards further molecular analysis of mosquito olfactory mechanism, such as recombinant expression and ligand identification.

  10. The effects of genetic manipulation, dieldrin treatment and irradiation on the mating competitiveness of male Anopheles arabiensis in field cages

    OpenAIRE

    Yamada, Hanano; Vreysen, Marc JB; Gilles, Jeremie RL; Munhenga, Givemore; Damiens, David D.

    2014-01-01

    Background To enable the release of only sterile male Anopheles arabiensis mosquitoes for the sterile insect technique, the genetic background of a wild-type strain was modified to create a genetic sexing strain ANO IPCL1 that was based on a dieldrin resistance mutation. Secondly, the eggs of ANO IPCL1 require treatment with dieldrin to allow complete elimination of female L1 larvae from the production line. Finally, male mosquito pupae need to be treated with an irradiation dose of 75 Gy for...

  11. Habitat capacity for Sacramento delta - Life Cycle Modeling of Life History Diversity and Habitat Relationships

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goals of this project are to examine 1) the relative importance of multiple aquatic habitats (streams, estuaries, and nearshore areas, for example) used by...

  12. Hydrodynamic Simulations of Physical Aquatic Habitat Availability for Pallid Sturgeon in the Lower Missouri River, at Yankton, South Dakota, Kenslers Bend, Nebraska, Little Sioux, Iowa, and Miami, Missouri, 2006-07

    Science.gov (United States)

    Jacobson, Robert B.; Johnson, Harold E.; Dietsch, Benjamin J.

    2009-01-01

    The objective of this study was to assess the sensitivity of habitat availability in the Lower Missouri River to discharge variation, with emphasis on habitats that might support spawning of the endangered pallid sturgeon. We constructed computational hydrodynamic models for four reaches that were selected because of evidence that sturgeon have spawned in them. The reaches are located at Miami, Missouri (river mile 259.6-263.5), Little Sioux, Iowa (river mile 669.6-673.5), Kenslers Bend, Nebraska (river mile 743.9-748.1), and Yankton, South Dakota reach (river mile 804.8-808.4). The models were calibrated for a range of measured flow conditions, and run for a range of discharges that might be affected by flow modifications from Gavins Point Dam. Model performance was assessed by comparing modeled and measured water velocities. A selection of derived habitat units was assessed for sensitivity to hydraulic input parameters (drag coefficient and lateral eddy viscosity). Overall, model results were minimally sensitive to varying eddy viscosity; varying lateral eddy viscosity by 20 percent resulted in maximum change in habitat units of 5.4 percent. Shallow-water habitat units were most sensitive to variation in drag coefficient with 42 percent change in unit area resulting from 20 percent change in the parameter value; however, no habitat unit value changed more than 10 percent for a 10 percent variation in drag coefficient. Sensitivity analysis provides guidance for selecting habitat metrics that maximize information content while minimizing model uncertainties. To assess model sensitivities arising from topographic variation from sediment transport on an annual time scale, we constructed separate models from two complete independent surveys in 2006 and 2007. The net topographic change was minimal at each site; the ratio of net topographic change to water volume in the reaches at 95 percent exceedance flow was less than 5 percent, indicating that on a reach

  13. The influence of late-stage pupal irradiation and increased irradiated:un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2009-01-01

    Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments

  14. Mating competitiveness of male Anopheles arabiensis mosquitoes irradiated with a partially or fully sterilizing dose in small and large laboratory cages

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2008-01-01

    Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of ei

  15. Mollusk Distribution and Habitat, Aquatic Invasive Species (AIS) animal distribution in Wisconsin - Zebra mussels, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Mollusk Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2009....

  16. Plant Distribution and Habitat, Other, Aquatic Invasive Species (AIS) plant distribution in Wisconsin - Milfoil hybrid, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Plant Distribution and Habitat, Other dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of...

  17. Plant Distribution and Habitat, Other, Aquatic Invasive Species (AIS) plant distribution in Wisconsin - Reed Canary Grass (30 meter raster), Published in 2007, 1:100000 (1in=8333ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Plant Distribution and Habitat, Other dataset, published at 1:100000 (1in=8333ft) scale, was produced all or in part from Uncorrected Imagery information as of...

  18. Plant Distribution and Habitat, Other, Aquatic Invasive Species (AIS) plant distribution in Wisconsin - Curly Leaf Pondweed, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Plant Distribution and Habitat, Other dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of...

  19. Plant Distribution and Habitat, Other, Aquatic Invasive Species (AIS) plant distribution in Wisconsin - Eurasian water milfoil, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Plant Distribution and Habitat, Other dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of...

  20. Arthropod Distribution and Habitat, Aquatic Invasive Species (AIS) animal distribution in Wisconsin - Rusty Crayfish, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Arthropod Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2009....

  1. Arthropod Distribution and Habitat, Aquatic Invasive Species (AIS) animal distribution in Wisconsin - Spiny/fishhook water flea, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Arthropod Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2009....

  2. Fish Distribution and Habitat, Aquatic Invasive Species (AIS) animal distribution in Wisconsin - Rainbow Smelt, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Fish Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2009. It...

  3. Jellyfish Distribution and Habitat, Aquatic Invasive Species (AIS) animal distribution in Wisconsin - Freshwater jellyfish, Published in 2009, 1:24000 (1in=2000ft) scale, Wisconsin DNR Bureau of Watershed Management.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Jellyfish Distribution and Habitat dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of 2009....

  4. Mating competitiveness of sterile genetic sexing strain males (GAMA) under laboratory and semi-field conditions: Steps towards the use of the Sterile Insect Technique to control the major malaria vector Anopheles arabiensis in South Africa

    OpenAIRE

    Munhenga, Givemore; Brooke, Basil D; Gilles, Jeremie R. L.; Slabbert, Kobus; Kemp, Alan,; Dandalo, Leonard C.; Wood, Oliver R.; Lobb, Leanne N.; Govender, Danny; Renke, Marius; Koekemoer, Lizette L

    2016-01-01

    Background Anopheles arabiensis Patton is primarily responsible for malaria transmission in South Africa after successful suppression of other major vector species using indoor spraying of residual insecticides. Control of An. arabiensis using current insecticide based approaches is proving difficult owing to the development of insecticide resistance, and variable feeding and resting behaviours. The use of the sterile insect technique as an area-wide integrated pest management system to suppl...

  5. The effect of larval nutritional deprivation on the life history and DDT resistance phenotype in laboratory strains of the malaria vector Anopheles arabiensis

    Directory of Open Access Journals (Sweden)

    Oliver Shüné V

    2013-02-01

    Full Text Available Abstract Background Anopheles arabiensis is a major malaria vector in Africa. It thrives in agricultural areas and has been associated with increased malaria incidence in areas under rice and maize cultivation. This effect may be due to increased adult size and abundance as a consequence of optimal larval nutrition. The aim of this study was to examine the effect of larval nutrition on the life history and expression of insecticide resistance in adults of laboratory reared An. arabiensis. Methods Larvae drawn from an insecticide susceptible An. arabiensis strain (SENN as well as a DDT-resistant strain (SENN-DDT were subjected to three fasting regimes: 1 mg of food per larva offered once per day, once every second day and once every third day. Control cohorts included larvae offered 1 mg food thrice per day. The rate of larval development was compared between matched cohorts from each strain as well as between fasted larvae and their respective controls. The expression of DDT resistance/tolerance in adults was compared between the starved cohorts and their controls by strain. Factors potentially affecting variation in DDT resistance/tolerance were examined including: adult body size (wing length, knock-down resistance (kdr status and levels of detoxification enzyme activity. Results and conclusion Anopheles arabiensis larval development is prolonged by nutrient deprivation and adults that eclose from starved larvae are smaller and less tolerant to DDT intoxication. This effect on DDT tolerance in adults is also associated with reduced detoxification enzyme activity. Conversely, well fed larvae develop comparatively quickly into large, more DDT tolerant (SENN or resistant (SENN-DDT adults. This is important in those instances where cereal farming is associated with increased An. arabiensis transmitted malaria incidence, because large adult females with high teneral reserves and decreased susceptibility to insecticide intoxication may also

  6. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    Directory of Open Access Journals (Sweden)

    Folb Peter I

    2010-10-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30% within two hours. Conclusions None of the plant extracts investigated exhibited residual repellencies >60% after three hours.

  7. Use of carbon-13 as a population marker for Anopheles arabiensis in a sterile insect technique (SIT context

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2006-01-01

    Full Text Available Abstract Background Monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the Sterile Insect Technique (SIT. Of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. Suitable ones include dye marking, genetic marking and chemical marking. Methods The feasibility of using the stable isotope of carbon, 13C, as a potential chemical marker for Anopheles arabiensis was evaluated in the laboratory. Labeled-13C glucose was incorporated into the larval diet in a powder or liquid form. The contribution of adult sugar feeding to the total mosquito carbon pool and the metabolically active carbon pool was determined by tracing the decline of the enrichment of the adult male mosquito as it switched from a labeled larval diet to an unlabeled adult diet. This decline in the adult was monitored by destructive sampling of the whole mosquito and analyzed using isotope ratio mass spectrometry. Results A two-pool model was used to describe the decline of the 13C-enrichment of adult mosquitoes. The proportion of the total adult carbon pool derived from the adult sugar diet over the life span of mosquitoes was determined and the ratio of structural carbon, with a low turnover rate to metabolically active non-structural carbon was assessed. The uptake and turnover of sugar in the metabolically active fraction suggests that after 3 days >70% of the active fraction carbon is derived from sugar feeding (increasing to >90% by day 7, indicating the high resource demand of male mosquitoes. Conclusion It was possible to "fix" the isotopic label in adult An. arabiensis and to detect the label at an appropriate concentration up to 21 days post-emergence. The optimum labeling treatment would cost around 250 US$ per million mosquitoes. Stable isotope marking may thus aid research on the fate of released insects besides other population

  8. Diversity of Aquatic Insects in Keniam River, National Park, Pahang, Malaysia

    Directory of Open Access Journals (Sweden)

    Mohd Rasdi, Z.

    2012-09-01

    Full Text Available The study on biodiversity of aquatic insects was carried out covering the area of Kuala Keniam to Kuala Perkai River, National Park, Pahang, Malaysia. The macro invertebrate community was found in the different types of micro-habitat and various flowing speed levels in good quality of water of Keniam Rivers consisted mainly of aquatic insects. There are large numbers and wide species of aquatic insects in aquatic habitats make them of great ecological importance. There are three divided strata with total of nine sampling location were carried out within several varieties of microhabitats such as sandy, cobble, gravel, leaf and the pool area. The aquatic insects were collected and sampled by using a D-framed aquatic kick net. There was a wide variety of aquatic insects belonging to at least 8 orders in the study area. The orders of insect were Odonata, Coleoptera, Diptera, Trichoptera, Thysanura, Orthopthera, Hemiptera and Ephemeroptera. Throughout the study period, there is range from total of 140 to 604 individuals of aquatic insect trapped monthly and collected in Keniam River from September 2009 to December 2010. Some group of aquatic insects were found significant (χ2<0.05 different abundance between strata and sampling dates as well as habitat on the diversity of aquatic insects in Keniam River. The abundance and distribution of aquatic insects‟ species were varied and not constant from one month to another during the study period due to biotic and abiotic factors. Species diversity of aquatic insects varied in different strata of the Keniam River. This indicates the richness and diverse groups of aquatic insects in the study area. It adds to the fact that the undisturbed habitat quality is most suitable for insects to breed and multiply under the natural ecosystem with abundant food supply. Moving upstream from Kuala Perkai to lower stream to Kuala Keniam, one can observe various types of habitats for aquatic insects to live.

  9. A field site for SIT control of Anopheles arabiensis in Northern State, Sudan: Analysis of historical data

    International Nuclear Information System (INIS)

    Full text: A field site suitable for SIT will have a single vector population that is isolated, unstructured, relatively small and low density. Disease transmission potential should be established and the cost benefit analysis of SIT should be favourable for the local community, nationally and regionally. Today's technology greatly facilitates the comprehensive and rapid assessment of these criteria, even if starting from zero, but an historical perspective is necessary. This paper researches data relevant to development of SIT for control of the malaria vector Anopheles arabiensis in Northern State, Sudan. The field site is primarily the Dongola Reach of the Nile extending from the Fourth Cataract to the Third Cataract. An. arabiensis is dependent on the river and the human population and is isolated by the desert. Northern State has an ancient history with important archaeological sites dating back to the Neolithic (4,500-3,500 BC). This has generated information on human health, settlement patterns and climate up to the medieval Christian and Islamic periods. The accounts of travellers and military historians provide data from the nineteenth century. In the early twentieth century there are detailed entomological and epidemiological records from the Wellcome Tropical Research Laboratories in Khartoum and later the Sudan Medical Service. Vector population studies increasingly rely on molecular genetic markers. These often have multiple interpretations that can be resolved by independent historical data that, for example, may infer the age of the current Northern State An. arabiensis population and how well isolated it has been. Entomological and hospital malaria records confirm the presence of A. arabiensis as early as 1906 and as far north as Wadi Halfa. It may have reached 150 km further north, at Ed Derr, in 1919 and certainly reached Asyut, 850 km into Egypt, in 1942. It was eradicated from Upper Egypt by 1945 and did not appear north of Ferka (250 km south

  10. Alabama ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare plants in Alabama. Vector polygons in this data set...

  11. Virginia ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare terrestrial plants/communities in Virginia. Vector...

  12. Maryland ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) and rare plants in Maryland. Vector polygons in this data set...

  13. Aquatic Therapy for Children

    Science.gov (United States)

    Kucher, Greta; Moore, Kelsey; Rodia, Rachel; Moser, Christy Szczech

    2015-01-01

    Aquatic therapy has long been highlighted in the literature as a potentially powerful therapeutic intervention. This review will highlight basic definitions of aquatic therapy, review salient research, and identify specific diagnoses that may benefit from aquatic therapy. Online resources, blogs, and books that occupational therapists may find…

  14. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    OpenAIRE

    Malcolm Colin A; El-Motasim Waleed M; Hassan Mo'awia M; Helinski Michelle EH; Knols Bart GJ; El-Sayed Badria

    2008-01-01

    Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosqui...

  15. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    OpenAIRE

    Folb Peter I; Bhagwandin Niresh; Newmarch Marion; Crouch Neil R; Maharaj Vinesh; Maharaj Rajendra; Pillay Pamisha; Gayaram Reshma

    2010-01-01

    Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodiu...

  16. Dynamics of immature stages of Anopheles arabiensis and other mosquito species (Diptera: Culicidae) in relation to rice cropping in a rice agro-ecosystem in Kenya.

    Science.gov (United States)

    Mwangangi, Joseph; Shililu, Josephat; Muturi, Ephantus; Gu, Weidong; Mbogo, Charles; Kabiru, Ephantus; Jacob, Benjamin; Githure, John; Novak, Robert

    2006-12-01

    We determined changes in species composition and densities of immature stages of Anopheles arabiensis mosquitoes in relation to rice growth cycle in order to generate data for developing larval control strategies in rice ecosystems. Experimental rice paddies (6.3m x 3.15m) exposed to natural colonization of mosquitoes were sampled weekly for two rice growing cycles between February 2004 and March 2005. Overall, 21,325 Anopheles larvae were collected, of which 91.9% were 1st and 2nd instars and 8.1% were 3rd and 4th instars. An. arabiensis was the predominant species (84.1%) with other species, An. pharoensis (13.5%), An. funestus (2.1%), An. coustani (0.3%), and An. maculipalpis (0.1%) accounting for only a small proportion of the anophelines collected. Culex quinquefasciatus (65.7%) was the predominant species among the non-anopheline species. Others species collected included: C. annulioris (9.9%), C. poicilipes (7.3%), C. tigripes (7.2%), C. duttoni (0.6%), Aedes aegypti (5.3%), Ae. cumminsii (3.5%), and Ae. vittatus (0.7%). The densities of the major anopheline species were closely related to rice stage and condition of the rice field. An. arabiensis, the predominant species, was most abundant over a three-week period after transplanting. Low densities of larvae were collected during the late vegetative, reproductive, and ripening phases of rice. An increase in larval density ten days post-transplanting was found to correlate with the application of fertilizer (sulphate of ammonia). Culicine and aedine species densities were significantly higher during the post-harvesting period. Our results suggest that the transplanting stage is favorable for the growth of immature stages of An. arabiensis and provides a narrow window for targeted larval intervention in rice. PMID:17249341

  17. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    OpenAIRE

    Malcolm Colin A; Benedict Mark Q; Knols Bart GJ; Hassan M'oawia M; Cox Jonathan; Ageep Tellal B; Babiker Ahmed; El Sayed Badria B

    2009-01-01

    Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were...

  18. Habitat connectivity and ecosystem productivity: implications from a simple model.

    Science.gov (United States)

    Cloern, J.E.

    2007-01-01

    The import of resources (food, nutrients) sustains biological production and food webs in resource-limited habitats. Resource export from donor habitats subsidizes production in recipient habitats, but the ecosystem-scale consequences of resource translocation are generally unknown. Here, I use a nutrient-phytoplankton-zooplankton model to show how dispersive connectivity between a shallow autotrophic habitat and a deep heterotrophic pelagic habitat can amplify overall system production in metazoan food webs. This result derives from the finite capacity of suspension feeders to capture and assimilate food particles: excess primary production in closed autotrophic habitats cannot be assimilated by consumers; however, if excess phytoplankton production is exported to food-limited heterotrophic habitats, it can be assimilated by zooplankton to support additional secondary production. Transport of regenerated nutrients from heterotrophic to autotrophic habitats sustains higher system primary production. These simulation results imply that the ecosystem-scale efficiency of nutrient transformation into metazoan biomass can be constrained by the rate of resource exchange across habitats and that it is optimized when the transport rate matches the growth rate of primary producers. Slower transport (i.e., reduced connectivity) leads to nutrient limitation of primary production in autotrophic habitats and food limitation of secondary production in heterotrophic habitats. Habitat fragmentation can therefore impose energetic constraints on the carrying capacity of aquatic ecosystems. The outcomes of ecosystem restoration through habitat creation will be determined by both functions provided by newly created aquatic habitats and the rates of hydraulic connectivity between them.

  19. Antimosquito properties of 2-substituted phenyl/benzylamino-6-(4-chlorophenyl)-5-methoxycarbonyl-4-methyl-3,6-dihydropyrimidin--ium chlorides against Anopheles arabiensis.

    Science.gov (United States)

    Narayanaswamy, Venugopala K; Gleiser, Raquel M; Chalannavar, Raju K; Odhav, Bharti

    2014-03-01

    Eight novel dihydropyrimidine analogs named DHPM1-DHPM8 was synthesized in their hydrochloride salt form using one pot synthesis between methyl 2-chloro-4-(4-chlorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate and substituted arylamines in isopropanol. The antimosquito effect of the test compounds were assessed against the adult mosquito Anopheles arabiensis. For adulticidal properties the test compounds were sprayed onto ceramic tiles and screened using the cone bio-assay method. The larvicidal activity was tested by monitoring larval mortality daily and up to 3 days of exposure. Repellency properties were tested in a feeding-probe assay using unfed female Anopheles arabiensis. Compounds DHPM1, DHPM4, DHPM5 and DHPM6 exerted larval mortality equivalent to temephos (trade name Abate, a commercial larvicidal compound). Compounds DHPM1 to DHPM5 repelled or knocked down 92 to 98% of mosquitoes exposed to rodent skin treated with the compounds. None of the compounds showed any significant activity against the adult mosquito Anopheles arabiensis. PMID:24506684

  20. Detection of the East and West African kdr mutation in Anopheles gambiae and Anopheles arabiensis from Uganda using a new assay based on FRET/Melt Curve analysis

    Directory of Open Access Journals (Sweden)

    Backeljau Thierry

    2006-02-01

    Full Text Available Abstract Background Appropriate monitoring of vector resistance to insecticides is an integral component of planning and evaluation of insecticide use in malaria control programmes. The malaria vectors Anopheles gambiae s.s. and Anopheles arabiensis have developed resistance to pyrethroid insecticides as a result of a mechanism conferring reduced nervous system sensitivity, better known as knockdown resistance (kdr. In An. gambiae s.s. and An. arabiensis, two different substitutions in the para-type sodium channel, a L1014F substitution common in West Africa and a L1014S replacement found in Kenya, are linked with kdr. Two different allele-specific polymerase chain reactions (AS-PCR are needed to detect these known kdr mutations. However, these AS-PCR assays rely on a single nucleotide polymorphism mismatch, which can result in unreliable results. Methods Here, a new assay for the detection of knockdown resistance in An. gambiae s.s. and An. arabiensis based on Fluorescence Resonance Energy Transfer/Melt Curve analysis (FRET/MCA is presented and compared with the existing assays. Results The new FRET/MCA method has the important advantage of detecting both kdr alleles in one assay. Moreover, results show that the FRET/MCA is more reliable and more sensitive than the existing AS-PCR assays and is able to detect new genotypes. By using this technique, the presence of the East African kdr mutation (L1014S is shown for the first time in An. arabiensis specimens from Uganda. In addition, a new kdr genotype is reported in An. gambiae s.s. from Uganda, where four An. gambiae s.s. mosquitoes possess both, the West (L1014F and East (L1014S African kdr allele, simultaneously. Conclusion The presence of both kdr mutations in the same geographical region shows the necessity of a reliable assay that enables to detect both mutations in one single assay. Hence, this new assay based on FRET/MCA will improve the screening of the kdr frequencies in An. gambiae s

  1. Loss and modification of habitat

    Science.gov (United States)

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold

    2012-01-01

    Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate

  2. Global ecological impacts of invasive species in aquatic ecosystems.

    Science.gov (United States)

    Gallardo, Belinda; Clavero, Miguel; Sánchez, Marta I; Vilà, Montserrat

    2016-01-01

    The introduction of invasive species, which often differ functionally from the components of the recipient community, generates ecological impacts that propagate along the food web. This review aims to determine how consistent the impacts of aquatic invasions are across taxa and habitats. To that end, we present a global meta-analysis from 151 publications (733 cases), covering a wide range of invaders (primary producers, filter collectors, omnivores and predators), resident aquatic community components (macrophytes, phytoplankton, zooplankton, benthic invertebrates and fish) and habitats (rivers, lakes and estuaries). Our synthesis suggests a strong negative influence of invasive species on the abundance of aquatic communities, particularly macrophytes, zooplankton and fish. In contrast, there was no general evidence for a decrease in species diversity in invaded habitats, suggesting a time lag between rapid abundance changes and local extinctions. Invaded habitats showed increased water turbidity, nitrogen and organic matter concentration, which are related to the capacity of invaders to transform habitats and increase eutrophication. The expansion of invasive macrophytes caused the largest decrease in fish abundance, the filtering activity of filter collectors depleted planktonic communities, omnivores (including both facultative and obligate herbivores) were responsible for the greatest decline in macrophyte abundance, and benthic invertebrates were most negatively affected by the introduction of new predators. These impacts were relatively consistent across habitats and experimental approaches. Based on our results, we propose a framework of positive and negative links between invasive species at four trophic positions and the five different components of recipient communities. This framework incorporates both direct biotic interactions (predation, competition, grazing) and indirect changes to the water physicochemical conditions mediated by invaders (habitat

  3. Inter-annual variation (1991-1993) of the substratum-leaf colonization dynamics for aquatic fauna in different habitats of the lake of the hydroelectric of Balbina, Amazon Central, Brazil; Variacao interanual (1991-1993) da dinamica de colonizacao de substrato-folha por fauna aquatica, em diferentes habitats do lago da Hidreletrica de Balbina, Amazonia Central, Amazonas- Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Vela-Pena, Gladys

    1996-07-01

    Experiments on fauna colonization of submersed vegetal substrate in different depths of water column were done to evaluate the benthic community structure in three habitats of the Balbina hydroelectric dam in 1991, 1992 and 1993. In these experiments substrate exposition periods of up to 60 and 75 days were done. The fauna associated to the standard substrate (Mabea caudata) belonged to seven phyla: Arthropoda, Coelenterata, Nematoda, Bryozoa, Annelida, Mollusca an Chordata. The most abundant and frequent families, during the studied period, were Naididae (Tubificida), Chydoridae (Cladocera) and Cenestheridae (Conchostraca), suggesting the persistence of these groups. In general, the pattern of colonization indicates some tendency to increase gradually with time of exposition of the substrate in the environment. Probably, the discontinuity of the tendencies is associated with the insects mobility and emergence. The initial colonization always was higher and quicker in the margin habitat, which indicates that the source of organisms is this habitat. This is due to better conditions of the environment such as availability of food and protection, associated with the submerged vegetation and wood. The community mean density during this study was 7, 312 ind/m{sup 2}. The density, the species richness index, and the diversity were correlated with abiotic variables such as pH, temperature, dissolved oxygen, habitat and depth. Also, the density was correlated with total carbon and ammonium. Species richness was correlated with total carbon, ammonium and water color. The density, diversity and species richness were proportionally inverse to depth of the habitats and total absence of organisms ago 10 meter of depth, different from what is found in bottom of natural environments. This fact was attributed to the high concentration of nutrients, such as ammonium and dissolved iron, to the existence of toxic gases such a sulphide, and to the conditions of hypoxia in the deep

  4. Lake Bathymetric Aquatic Vegetation

    Data.gov (United States)

    Minnesota Department of Natural Resources — Aquatic vegetation represented as polygon features, coded with vegetation type (emergent, submergent, etc.) and field survey date. Polygons were digitized from...

  5. Comparison of two methods for estimating the abundance, diversity and habitat preference of fluvial macroinvertebrates in contrasting habitats

    NARCIS (Netherlands)

    Alonso, A.; Camargo, J.A.

    2010-01-01

    In this research we evaluate the effects of the method used for estimating the potential surface available for benthic macroinvertebrates in macrophyte and unvegetated habitats on several metrics and habitat preference of aquatic macroinvertebrates in the upper catchment of the Henares River (Guadal

  6. Predicting submerged aquatic vegetation cover and occurrence in a Lake Superior estuary

    Science.gov (United States)

    Submerged aquatic vegetation (SAV) provides the biophysical basis for multiple ecosystem services in Great Lakes estuaries. Understanding sources of variation in SAV is necessary for sustainable management of SAV habitat. From data collected in 2011 using hydroacoustic survey met...

  7. A stable isotope dual-labelling approach to detect multiple insemination in un-irradiated and irradiated Anopheles arabiensis mosquitoes

    Directory of Open Access Journals (Sweden)

    Hood Rebecca C

    2008-04-01

    Full Text Available Abstract Background In the context of a Sterile Insect Technique programme, the occurrence of multiple insemination in the malaria mosquito Anopheles arabiensis Patton was studied using a novel labelling system with the stable isotopes 15N and 13C. The incidence of multiple insemination in the absence of radiation, and when males were irradiated in the pupal stage and competed against un-irradiated males were assessed. Males used in the experiments were labelled with either 15N or 13C and the label was applied to the larval rearing water. Males with either label and virgin females were caged at a 1:1:1 ratio. Males used in the radiation treatments were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. After mating, females were dissected and inseminated spermathecae analysed using mass spectrometry. Results The data indicate that about 25% of inseminated females had been inseminated multiply. The presence of irradiated males in the experiments did not affect the incidence of multiple insemination. In line with previous research, irradiated males were generally less competitive than un-irradiated males. Conclusion The implications of these findings for the Sterile Insect Technique are discussed, and further experiments recommended. The dual-labelling system used to determine paternity gave good results for 13C, however, for 15N it is recommended to increase the amount of label in future studies.

  8. Intracellular proliferation of Legionella pneumophila in Hartmannella vermiformis in aquatic biofilms grown on plasticized polyvinyl chloride

    NARCIS (Netherlands)

    Kuiper, M.W.; Wullings, B.A.; Akkermans, A.D.L.; Beumer, R.R.; Kooij, van der D.

    2004-01-01

    The need for protozoa for the proliferation of Legionella pneumophila in aquatic habitats is still not fully understood and is even questioned by some investigators. This study shows the in vivo growth of L. pneumophila in protozoa in aquatic biofilms developing at high concentrations on plasticized

  9. Broad-Scale Comparison of Photosynthesis in Terrestrial and Aquatic Plant Communities

    DEFF Research Database (Denmark)

    Sand-Jensen, Kaj; Krause-Jensen, D.

    1997-01-01

    Comparisons of photosynthesis in terrestrial and aquatic habitats have been impaired by differences in methods and time-scales of measurements. We compiled information on gross photosynthesis at high irradiance and photosynthetic efficiency at low irradiance from 109 published terrestrial studies...... of forests, grasslands and crops and 319 aquatic studies of phytoplankton, macrophyte and attached microalgal communities to test if specific differences existed between the communities. Maximum gross photosynthesis and photosynthetic efficiency were systematically higher in terrestrial than in aquatic...

  10. The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis.

    Science.gov (United States)

    Ibrahim, Sulaiman S; Riveron, Jacob M; Stott, Robert; Irving, Helen; Wondji, Charles S

    2016-01-01

    Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools.

  11. The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis

    Science.gov (United States)

    Ibrahim, Sulaiman S.; Riveron, Jacob M.; Stott, Robert; Irving, Helen; Wondji, Charles S.

    2016-01-01

    Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools. PMID:26548743

  12. Mathematical evaluation of community level impact of combining bed nets and indoor residual spraying upon malaria transmission in areas where the main vectors are Anopheles arabiensis mosquitoes

    Directory of Open Access Journals (Sweden)

    Okumu Fredros O

    2013-01-01

    Full Text Available Abstract Background Indoor residual insecticide spraying (IRS and long-lasting insecticide treated nets (LLINs are commonly used together even though evidence that such combinations confer greater protection against malaria than either method alone is inconsistent. Methods A deterministic model of mosquito life cycle processes was adapted to allow parameterization with results from experimental hut trials of various combinations of untreated nets or LLINs (Olyset®, PermaNet 2.0®, Icon Life® nets with IRS (pirimiphos methyl, lambda cyhalothrin, DDT, in a setting where vector populations are dominated by Anopheles arabiensis, so that community level impact upon malaria transmission at high coverage could be predicted. Results Intact untreated nets alone provide equivalent personal protection to all three LLINs. Relative to IRS plus untreated nets, community level protection is slightly higher when Olyset® or PermaNet 2.0® nets are added onto IRS with pirimiphos methyl or lambda cyhalothrin but not DDT, and when Icon Life® nets supplement any of the IRS insecticides. Adding IRS onto any net modestly enhances communal protection when pirimiphos methyl is sprayed, while spraying lambda cyhalothrin enhances protection for untreated nets but not LLINs. Addition of DDT reduces communal protection when added to LLINs. Conclusions Where transmission is mediated primarily by An. arabiensis, adding IRS to high LLIN coverage provides only modest incremental benefit (e.g. when an organophosphate like pirimiphos methyl is used, but can be redundant (e.g. when a pyrethroid like lambda cyhalothin is used or even regressive (e.g. when DDT is used for the IRS. Relative to IRS plus untreated nets, supplementing IRS with LLINs will only modestly improve community protection. Beyond the physical protection that intact nets provide, additional protection against transmission by An. arabiensis conferred by insecticides will be remarkably small, regardless of

  13. Investigations of Altered Aquatic Ecosystems: Biomonitoring, Disease, and Conservation

    OpenAIRE

    Lunde, Kevin Bryce

    2011-01-01

    Changes to hydrology, water chemistry, physical habitat, and the landscape surrounding aquatic ecosystems can have profound effects on their biological communities, potentially reducing important ecosystem services and functions provided to wildlife and humans. In this dissertation, I examine how environmental variables, human activities, and management practices have affected stream and wetland biota throughout Northern California. The parasitic trematode Ribeiroia ondatrae has been shown to...

  14. CAM Photosynthesis in Submerged Aquatic Plants

    Science.gov (United States)

    Keeley, J.E.

    1998-01-01

    Crassulacean acid metabolism (CAM) is a CO2-concentrating mechanism selected in response to aridity in terrestrial habitats, and, in aquatic environments, to ambient limitations of carbon. Evidence is reviewed for its presence in five genera of aquatic vascular plants, including Isoe??tes, Sagittaria, Vallisneria, Crassula, and Littorella. Initially, aquatic CAM was considered by some to be an oxymoron, but some aquatic species have been studied in sufficient detail to say definitively that they possess CAM photosynthesis. CO2-concentrating mechanisms in photosynthetic organs require a barrier to leakage; e.g., terrestrial C4 plants have suberized bundle sheath cells and terrestrial CAM plants high stomatal resistance. In aquatic CAM plants the primary barrier to CO2 leakage is the extremely high diffusional resistance of water. This, coupled with the sink provided by extensive intercellular gas space, generates daytime CO2(Pi) comparable to terrestrial CAM plants. CAM contributes to the carbon budget by both net carbon gain and carbon recycling, and the magnitude of each is environmentally influenced. Aquatic CAM plants inhabit sites where photosynthesis is potentially limited by carbon. Many occupy moderately fertile shallow temporary pools that experience extreme diel fluctuations in carbon availability. CAM plants are able to take advantage of elevated nighttime CO2 levels in these habitats. This gives them a competitive advantage over non-CAM species that are carbon starved during the day and an advantage over species that expend energy in membrane transport of bicarbonate. Some aquatic CAM plants are distributed in highly infertile lakes, where extreme carbon limitation and light are important selective factors. Compilation of reports on diel changes in titratable acidity and malate show 69 out of 180 species have significant overnight accumulation, although evidence is presented discounting CAM in some. It is concluded that similar proportions of the aquatic

  15. Science to support aquatic animal health

    Science.gov (United States)

    Purcell, Maureen K.; Harris, M. Camille

    2016-10-18

    Healthy aquatic ecosystems are home to a diversity of plants, invertebrates, fish and wildlife. Aquatic animal populations face unprecedented threats to their health and survival from climate change, water shortages, habitat alteration, invasive species and environmental contaminants. These environmental stressors can directly impact the prevalence and severity of disease in aquatic populations. For example, periodic fish kills in the upper Chesapeake Bay Watershed are associated with many different opportunistic pathogens that proliferate in stressed fish populations. An estimated 80 percent of endangered juvenile Puget Sound steelhead trout die within two weeks of entering the marine environment, and a role for disease in these losses is being investigated. The introduction of viral hemorrhagic septicemia virus (VHSV) into the Great Lakes—a fishery worth an estimated 7 billion dollars annually—resulted in widespread fish die-offs and virus detections in 28 different fish species. Millions of dying sea stars along the west coast of North America have led to investigations into sea star wasting disease. U.S. Geological Survey (USGS) scientists are assisting managers with these issues through ecological investigations of aquatic animal diseases, field surveillance, and research to promote the development of mitigation strategies.

  16. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2008-04-01

    Full Text Available Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosquitoes were irradiated in Khartoum and transported as adults by air to the field site earmarked for future releases (400 km from the laboratory. The field cage was prepared for experiments by creating resting sites with favourable conditions. The mating and survival of (irradiated laboratory males and field-collected males was studied in the field cage, and two small-scale competition experiments were performed. Results Minor problems were experienced with the irradiation of insects, mostly associated with the absence of a rearing facility in close proximity to the irradiation source. The small-scale transportation of adult mosquitoes to the release site resulted in minimal mortality ( Conclusion It is concluded that although conditions are challenging, there are no major obstacles associated with the small-scale irradiation and transportation of insects in the current setting. The field cage is suitable for experiments and studies to test the competitiveness of irradiated males can be pursued. The scaling up of procedures to accommodate much larger numbers of insects needed for a release is the next challenge and recommendations to further implementation of this genetic control strategy are presented.

  17. A 15N stable isotope semen label to detect mating in the malaria mosquito Anopheles arabiensis Patton

    Directory of Open Access Journals (Sweden)

    Gludovacz Doris

    2008-07-01

    Full Text Available Abstract In previous studies it was determined that the stable isotope 13-carbon can be used as a semen label to detect mating events in the malaria mosquito Anopheles arabiensis. In this paper we describe the use of an additional stable isotope, 15-nitrogen (15N, for that same purpose. Both stable isotopes can be analysed simultaneously in a mass spectrometer, offering the possibility to detect both labels in one sample in order to study complex and difficult-to-detect mating events, such as multiple mating. 15N-glycine was added to larval rearing water and the target enrichment was 5 atom% 15N. Males from these trays were mated with unlabelled virgin females, and spiked spermathecae were analysed for isotopic composition after mating using mass spectrometry. Results showed that spermathecae positive for semen could be distinguished from uninseminated or control samples using the raw δ15N‰ values. The label persisted in spermathecae for up to 5 days after insemination, and males aged 10 days transferred similar amounts of label as males aged 4 days. There were no negative effects of the label on larval survival and male longevity. Enrichment of teneral mosquitoes after emergence was 4.85 ± 0.10 atom% 15N. A threshold value defined as 3 standard deviations above the mean of virgin (i.e. uninseminated spermathecae samples was successful in classifying a large proportion of samples correctly (i.e. on average 95%. We conclude that alongside 13C, 15N can be used to detect mating in Anopheles and the suitability of both labels is briefly discussed.

  18. Nitrous Oxide Emission by Aquatic Macrofauna

    DEFF Research Database (Denmark)

    Stief, Peter; Nielsen, Lars Peter; Schramm, Andreas

    not ingest large quantities of microorganisms produced insignificant amounts of nitrous oxide. With increasing eutrophication, filter- and deposit-feeders often become the dominant feeding guilds of benthic communities. Thus, with increasing nitrate pollution, aquatic macrofauna has the potential to further......Many macrofauna species co-ingest large quantities of microorganisms some of which survive the gut passage. Denitrifying bacteria, in particular, become metabolically induced by anoxic conditions, nitrate, and labile organic compounds in the gut of invertebrates. A striking consequence of the short......, respectively. Aside from these case studies, we screened more than 20 macrofauna species in various aquatic habitats for nitrous oxide production. Filter- and deposit-feeders that ingest large quantities of microorganisms were the most important emitters of nitrous oxide. In contrast, predatory species that do...

  19. Sustainable exploitation and management of aquatic resources

    DEFF Research Database (Denmark)

    Neuenfeldt, Stefan; Köster, Fritz

    2014-01-01

    DTU Aqua conducts research, provides advice,educates at university level and contributes toinnovation in sustainable exploitation andmanagement of aquatic resources. The vision of DTUAqua is to enable ecologically and economicallysustainable exploitation of aquatic resourcesapplying an integrated...... management. Marineecosystems aims at understanding the mechanisms that govern the interaction between individuals,species and populations in an ecosystem enabling us to determine the stability and flexibility of theecosystem.Marine living resources looks at the sustainable utilization of fish and shellfish...... habitats – from the North Atlantic Oceanand European shelf areas to coastal areas and innerDanish waters, ecosystems in lakes and streams as well as aquaculture. European shelf seas, Danish coastalareas and freshwaters are our main working areas, but we also work on Arctic and sub-Arctic waters...

  20. Aquatic Life Benchmarks

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aquatic Life Benchmarks is an EPA-developed set of criteria for freshwater species. These benchmarks are based on toxicity values reviewed by EPA and used in...

  1. Aquatic Research Laboratory (ARL)

    Data.gov (United States)

    Federal Laboratory Consortium — Columbia River and groundwater well water sources are delivered to the Aquatic Research Laboratory (ARL), where these resources are used to conduct research on fish...

  2. Habitats of North American sea ducks.

    Science.gov (United States)

    Derksen, Dirk V.; Petersen, Margaret R.; Savard, Jean-Pierre L.

    2015-01-01

    Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks. Strategies for sea duck habitat management are outlined and recommendations for international collaboration to preserve key terrestrial and aquatic habitats are advanced. We follow the definition of habitat advanced by Odum (1971), which is the place or space where an organism lives. Weller (1999) emphasized that habitats for waterbirds required presence of sufficient resources (i.e., food, water, cover, space) for maintenance during a portion of their annual cycle. Habitats exploited by North American sea ducks are diverse, widespread across the continent and adjacent marine waters and until recently, most were only superficially known. Even following a 15-year-long effort through the Sea Duck Joint Venture and U.S. and Canadian Endangered/Threatened Species programs to fund research focused on sea duck habitats there are still important gaps in our understanding of key elements required by some species during various life stages. Importantly, many significant habitats, especially staging and wintering sites, have been and continue to be destroyed or altered, largely as a result of anthropogenic effects. Our goal here is to develop a comprehensive summary of marine, freshwater, and terrestrial habitats and their characteristics by considering sea duck species with similar needs as groups (e.g., eiders) within the tribe Mergini. Additionally, this chapter will examine threats and changes to sea duck habitats from human-caused and natural events. Finally, we will evaluate conservation and management programs underway or available for maintenance and enhancement of habitats critical for

  3. Restoring Damaged Aquatic Ecosystems

    OpenAIRE

    Cairns, John

    2006-01-01

    Aquatic ecosystems must play a major role to ensure that water, which is both essential and scarce, is always available for both present and future generations. This has become even more urgent in light of the ongoing increase in total world population and predicted changes in the world climate. Since aquatic ecosystems have been damaged at a rate far in excess of both natural restoration and anthropogenic restoration, it is essential that both restorative processes be accelerated. However, e...

  4. Introducing Aquatic Biology

    OpenAIRE

    Kinne, Otto; Browman, Howard I.; Seaman, Matthias

    2007-01-01

    The Inter-Research Science Center (IR) journals Marine Ecology Progress Series (MEPS) and Aquatic Microbial Ecology (AME) have been receiving increasing numbers of high-quality manuscripts that are principally biological, rather than ecological. With regret, we have had to turn these submissions away. Also, leading limnologists have for many years suggested that IR should provide an outlet for top quality articles on freshwater biology and ecology. Aquatic Biology (...

  5. Molecular ecology of aquatic microbes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    Abstracts of reports are presented from a meeting on Molecular Ecology of Aquatic Microbes. Topics included: opportunities offered to aquatic ecology by molecular biology; the role of aquatic microbes in biogeochemical cycles; characterization of the microbial community; the effect of the environment on aquatic microbes; and the targeting of specific biological processes.

  6. Understanding potential feedbacks in aquatic systems: submerged aquatic plans and turbidity in the Sacramento-San Joaquin River Delta.

    Science.gov (United States)

    Hestir, E. L.; Schoellhamer, D.; Santos, M. J.; Morgan, T.; Ustin, S. L.

    2008-12-01

    Invasive submerged aquatic plants can reduce the ecological health of estuaries; they act as ecosystem engineers, altering the physical habitat they colonize and induce feedback mechanisms. Once established, submerged plants can reduce flow, attenuate wave energy, decrease turbidity, and increase sedimentation. Altered sediment transport influences the geomorphology and the rate and type of change of biogeochemical processes in wetlands and floodplains. Contaminants such as mercury, polychlorinated biphenyls (PCBs), and organochlorine (OC) pesticides adsorb onto sediments, and increased bed sedimentation can impact benthic habitat quality. Using a combination of in situ and remote sensing data in a GIS, we analyzed the impact of established submerged aquatic plants on turbidity at the ecosystem-wide scale and at a site- specific scale in the Sacramento-San Joaquin River Delta, CA. Annual areal estimates of submerged plant cover were derived from classification of airborne hyperspectral remote sensing data from 2004 to 2008, which average 11% of the 2000 km2 waterways. These data were used in conjunction with turbidity and velocity recorded at monitoring stations in the Delta. Extensive point sampling of turbidity and submerged aquatic plant biomass were conducted concurrent with airborne remote sensing imagery in 2008. Submerged aquatic plant cover was mapped with an accuracy of 70-90% per year. We found a negative effect of established submerged aquatic plant cover/biomass on water speed and turbidity, both at the local and ecosystem levels. Furthermore, our results suggest a threshold of plant cover that triggers its impact on system-wide turbidity measurements. These results reinforce that submerged aquatic plants may be functioning as biogeomorphic agents, or ecosystem engineers, by altering system hydrodynamics and aquatic habitat.

  7. Landscape determinants and remote sensing of anopheline mosquito larval habitats in the western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Beck Louisa

    2006-02-01

    Full Text Available Abstract Background In the past two decades the east African highlands have experienced several major malaria epidemics. Currently there is a renewed interest in exploring the possibility of anopheline larval control through environmental management or larvicide as an additional means of reducing malaria transmission in Africa. This study examined the landscape determinants of anopheline mosquito larval habitats and usefulness of remote sensing in identifying these habitats in western Kenya highlands. Methods Panchromatic aerial photos, Ikonos and Landsat Thematic Mapper 7 satellite images were acquired for a study area in Kakamega, western Kenya. Supervised classification of land-use and land-cover and visual identification of aquatic habitats were conducted. Ground survey of all aquatic habitats was conducted in the dry and rainy seasons in 2003. All habitats positive for anopheline larvae were identified. The retrieved data from the remote sensors were compared to the ground results on aquatic habitats and land-use. The probability of finding aquatic habitats and habitats with Anopheles larvae were modelled based on the digital elevation model and land-use types. Results The misclassification rate of land-cover types was 10.8% based on Ikonos imagery, 22.6% for panchromatic aerial photos and 39.2% for Landsat TM 7 imagery. The Ikonos image identified 40.6% of aquatic habitats, aerial photos identified 10.6%, and Landsate TM 7 image identified 0%. Computer models based on topographic features and land-cover information obtained from the Ikonos image yielded a misclassification rate of 20.3–22.7% for aquatic habitats, and 18.1–25.1% for anopheline-positive larval habitats. Conclusion One-metre spatial resolution Ikonos images combined with computer modelling based on topographic land-cover features are useful tools for identification of anopheline larval habitats, and they can be used to assist to malaria vector control in western Kenya

  8. Impact of sampling efficiency on the performance of data-driven fish habitat models

    OpenAIRE

    Mouton, A.M.; Dillen, A.; Van den Neucker, T.; Buysse, D.; STEVENS, M.; Coeck, J.

    2012-01-01

    In the last decades, aquatic habitat modelling has gained more attention due to its relevance to river management, restoration and conservation biology. Although numerous habitat suitability models have been developed based on ecological data, data quality is often a key, but overlooked issue in the development of such models. This paper analysed the impact of sampling efficiency on the quality of data-driven habitat suitability models. Therefore, models were derived from fish habitat data ob...

  9. Habitat suitability and ecological niche profile of major malaria vectors in Cameroon

    Directory of Open Access Journals (Sweden)

    Agbor Jean-Pierre

    2009-12-01

    Full Text Available Abstract Background Suitability of environmental conditions determines a species distribution in space and time. Understanding and modelling the ecological niche of mosquito disease vectors can, therefore, be a powerful predictor of the risk of exposure to the pathogens they transmit. In Africa, five anophelines are responsible for over 95% of total malaria transmission. However, detailed knowledge of the geographic distribution and ecological requirements of these species is to date still inadequate. Methods Indoor-resting mosquitoes were sampled from 386 villages covering the full range of ecological settings available in Cameroon, Central Africa. Using a predictive species distribution modeling approach based only on presence records, habitat suitability maps were constructed for the five major malaria vectors Anopheles gambiae, Anopheles funestus, Anopheles arabiensis, Anopheles nili and Anopheles moucheti. The influence of 17 climatic, topographic, and land use variables on mosquito geographic distribution was assessed by multivariate regression and ordination techniques. Results Twenty-four anopheline species were collected, of which 17 are known to transmit malaria in Africa. Ecological Niche Factor Analysis, Habitat Suitability modeling and Canonical Correspondence Analysis revealed marked differences among the five major malaria vector species, both in terms of ecological requirements and niche breadth. Eco-geographical variables (EGVs related to human activity had the highest impact on habitat suitability for the five major malaria vectors, with areas of low population density being of marginal or unsuitable habitat quality. Sunlight exposure, rainfall, evapo-transpiration, relative humidity, and wind speed were among the most discriminative EGVs separating "forest" from "savanna" species. Conclusions The distribution of major malaria vectors in Cameroon is strongly affected by the impact of humans on the environment, with variables

  10. Characterization of anopheline (Diptera: Culicidae larval habitats in Nouakchott, Mauritania

    Directory of Open Access Journals (Sweden)

    O. Ahmedou Salem Mohamed Salem

    2013-12-01

    Full Text Available Background & objectives: Despite the increasing number of reported autochthonous malaria cases in Nouakchott and the identification of Anopheles arabiensis as the major malaria vector in this Saharan city, anopheline larval habitats have never been identified so far. The objective of this study was to identify and characterize anopheline larval habitats in Nouakchott. Methods: During September and October 2012, samples from pools of rainwater, water discharged from standpipes and household drinking water tanks in the districts of Dar Naim, Teyarett and Arafat were analyzed for the presence/absence of anopheline larvae and physicochemical characterization of breeding habitats. Results: Of the 51 prospected water bodies, eight consisting of seven water discharged from standpipes and one household drinking water tank were productive for Anopheles sp. All emerged anopheline mosquitoes from the positive dipping were morphologically identified as members of the An. gambiae complex. Multivariate regression analyses showed that a salinity up to 0.1 g/l and a shaded situation were respectively protective factors against high larval density in breeding sites (adjusted odds ratio = 0.62, 95% CI [0.44-0.87], p = 0.0052 and adjusted odds ratio = 0.56, 95% CI [0.44-0.71, p <0.0001] and a pH up to 7.61 was a risk factor for high larval density in breeding sites (adjusted odds ratio = 1.56, 95% CI [1.25-1.95], p = 0.0001. Interpretation & conclusion: The study demonstrated in Nouakchott that despite an arid and dry climate, human practices have contributed to the establishment of favourable environmental conditions for the development of anopheline mosquitoes and, therefore, maintaining malaria transmission in this Saharan city. The core malaria vector control intervention as the use of long-lasting insecicidal nets (LLINs could be complemented in Nouakchott by larval source control. In this area, appropriate larval control measures may be recommended in line

  11. Colorado Plateau Rapid Ecoregion Assessment Management Question B7: What is the location/distribution of these aquatic biodiversity sites?

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This map shows water features where aquatic biodiversity is likely to be important. It shows buffered streams, wetlands, and deepwater habitats that fall within...

  12. Physical habitat structure of the lake shoreline and littoral zone -- How important is it?

    Science.gov (United States)

    The recent National Lakes Assessment (NLA) included the first national assessment of littoral and lakeshore physical habitat. It quantified water depth, surface characteristics, bank morphology, lake level fluctuations, substrate, fish concealment features, aquatic macrophytes, l...

  13. Contaminant discharge in habitat springs of the Barton Springs Salamander during storm rainfall events

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Aquatic habitat of the endangered Barton Springs salamander, Eurycea sosorum, in Travis County, Texas can potentially be impacted by contaminants in surface runoff...

  14. WILDLIFE HABITAT INVENTORY

    OpenAIRE

    GÜNDOĞDU, Ebubekir

    2009-01-01

    This study focused on what does habitat mean in wildlife, which factors it contains, how to make inventory for these factors and how to analyses habitat according to chosen species. In spite of habitat inventory has various meanings for varying areas and species by examining literature on this issue the most preferred habitat inventory standards are presented in this article. Keywords: Habitat, Inventory, Mapping

  15. Microbial biotechnology for remediation of aquatic habitats polluted with chromium

    Directory of Open Access Journals (Sweden)

    Viorica Coşier

    2008-12-01

    Full Text Available Chromium may occur in nine different forms of oxidation ranging from ?II to +VI, with forms II, III and VI as the most commonly encountered. In Cluj county, chromium pollution dates well back in time and has caused important dysfunction to the mechanical-biological wastewater purification station of the city of Cluj (Coşier & Diţă 1996. The purpose of this study was to develop one microbial method able to reduce hexavalent chromium (mobile, permeable to cell membrane, carcinogenic and mutagenic (Ishikawa et al 1994 to the trivalent form (insoluble and an essential element for humans (Song et al 2006. Different sources of chromium-reducing bacteria and many sources of carbon and energy added to the Kvasnikov mineral basal medium (Komori et al 1990 with increasing amount of chromate (200- 1000 mg/l were tested. Two bacterial strains, able to reduce even 1000 mg chromate/l, were isolated in pure culture. For one of these bacterial strains, we determined the optimum conditions for the reduction of Cr (VI.

  16. Finfish and aquatic invertebrate pathology resources for now and the future✩

    Science.gov (United States)

    Spitsbergen, Jan M.; Blazer, Vicki S.; Bowser, Paul R.; Cheng, Keith C.; Cooper, Keith R.; Cooper, Timothy K.; Frasca, Salvatore; Groman, David B.; Harper, Claudia M.; (Mac) Law, Jerry M.; Marty, Gary D.; Smolowitz, Roxanna M.; Leger, Judy St.; Wolf, Douglas C.; Wolf, Jeffrey C.

    2009-01-01

    Utilization of finfish and aquatic invertebrates in biomedical research and as environmental sentinels has grown dramatically in recent decades. Likewise the aquaculture of finfish and invertebrates has expanded rapidly worldwide as populations of some aquatic food species and threatened or endangered aquatic species have plummeted due to overharvesting or habitat degradation. This increasing intensive culture and use of aquatic species has heightened the importance of maintaining a sophisticated understanding of pathology of various organ systems of these diverse species. Yet, except for selected species long cultivated in aquaculture, pathology databases and the workforce of highly trained pathologists lag behind those available for most laboratory animals and domestic mammalian and avian species. Several factors must change to maximize the use, understanding, and protection of important aquatic species: 1) improvements in databases of abnormalities across species; 2) standardization of diagnostic criteria for proliferative and nonproliferative lesions; and 3) more uniform and rigorous training in aquatic morphologic pathology. PMID:18948226

  17. The Habitat Connection.

    Science.gov (United States)

    Naturescope, 1987

    1987-01-01

    Consists of activities which address the causes of habitat destruction and the effects of habitat loss on animals and plants. Identifies habitat loss as the major reason for the endangerment and extinction of plant and animal species. (ML)

  18. Louisiana ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types,...

  19. Contaminated Aquatic Sediments.

    Science.gov (United States)

    Jaglal, Kendrick

    2016-10-01

    A review of the literature published in 2015 relating to the assessment, evaluation and remediation of contaminated aquatic sediments is presented. The review is divided into the following main sections: policy and guidance, methodology, distribution, fate and transport, risk, toxicity and remediation. PMID:27620103

  20. Aquatic Environment 2000

    DEFF Research Database (Denmark)

    Svendsen, L. M.; Bijl, L. van der; Boutrup, S.;

    The report summarizes the results of the Danish Aquatic Monitoring and Assessment Programme 1998-2003. Danish Environmental Protection Agency 2000: NOVA-2003. Programbeskrivelse for det nationale program for overvågning af vandmiljøet 1998-2003. 397 pp. - Redegørelse fra Miljøstyrelsen nr. 1 (in...

  1. EcologicHabitat_WLH

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage habitats (WLH)...

  2. Aquatic Pest Control. Manual 99.

    Science.gov (United States)

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the aquatic pest control category. The text discusses various water use situations; aquatic weed identification; herbicide use and effects; and aquatic insects and their control. (CS)

  3. Introduced aquatic plants and algae

    Science.gov (United States)

    Non-native aquatic plants such as waterhyacinth and hydrilla severely impair the uses of aquatic resources including recreational faculties (lakes, reservoirs, rivers) as well as timely delivery of irrigation water for agriculture. Costs associated with impacts and management of all types of aquatic...

  4. The Role of Oxidative Stress in the Longevity and Insecticide Resistance Phenotype of the Major Malaria Vectors Anopheles arabiensis and Anopheles funestus.

    Directory of Open Access Journals (Sweden)

    Shüné V Oliver

    Full Text Available Oxidative stress plays numerous biological roles, both functional and pathological. The role of oxidative stress in various epidemiologically relevant biological traits in Anopheles mosquitoes is not well established. In this study, the effects of oxidative stress on the longevity and insecticide resistance phenotype in the major malaria vector species An. arabiensis and An. funestus were examined. Responses to dietary copper sulphate and hydrogen peroxide were used as proxies for the oxidative stress phenotype by determining the effect of copper on longevity and hydrogen peroxide lethal dose. Glutathione peroxidase and catalase activities were determined colorimetrically. Oxidative burden was quantified as protein carbonyl content. Changes in insecticide resistance phenotype were monitored by WHO bioassay. Insecticide resistant individuals showed an increased capacity for coping with oxidative stress, mediated by increased glutathione peroxidase and catalase activity. This effect was observed in both species, as well as in laboratory strains and F1 individuals derived from wild-caught An. funestus mothers. Phenotypic capacity for coping with oxidative stress was greatest in strains with elevated Cytochrome P450 activity. Synergism of oxidative stress defence enzymes by dietary supplementation with haematin, 3-Amino-1, 2, 4-triazole and Sodium diethyldithiocarbamate significantly increased pyrethroid-induced mortality in An. arabiensis and An. funestus. It is therefore concluded that defence against oxidative stress underlies the augmentation of the insecticide resistance phenotype associated with multiple blood-feeding. This is because multiple blood-feeding ultimately leads to a reduction of oxidative stress in insecticide resistant females, and also reduces the oxidative burden induced by DDT and pyrethroids, by inducing increased glutathione peroxidase activity. This study highlights the importance of oxidative stress in the longevity and

  5. Sea Level Affecting Marshes Model (SLAMM)‐New Functionality for Predicting Changes in Distribution of Submerged Aquatic Vegetation in Response to Sea Level Rise.Version 1.0

    Science.gov (United States)

    Submerged aquatic vegetation (SAV) is an ecologically important habitat world-wide. In Pacific Northwest (PNW) estuaries, SAV in the lower intertidal and shallow subtidal habitats are dominated by the native seagrass, Zostera marina also referred to as submerged aquatic vegetati...

  6. Aquatic Ecology Section

    International Nuclear Information System (INIS)

    Population studies were concerned with predicting long-term consequences of mortality imposed on animal populations by man's activities. These studies consisted of development of a generalized life cycle model and an empirical impingement model for use in impact analysis. Chemical effects studies were conducted on chlorine minimization; fouling by the Asiatic clam; identification of halogenated organics in cooling water; and effects of halogenated organics in cooling systems on aquatic organisms. Ecological transport studies were conducted on availability of sediment-bound 137Cs and 60Co to fish; 137Cs and 60Co in White Oak Lake fish; and chromium levels in fish from a lake chronically contaminated with chromates from cooling towers. Progress is also reported on the following: effects of irradiation on thermal tolerance of mosquito fish; toxicity of nickel to the developing eggs and larvae of carp; accumulation of selected heavy metals associated with fly ash; and environmental monitoring of aquatic ecosystems

  7. Scaling macroscopic aquatic locomotion

    Science.gov (United States)

    Gazzola, Mattia; Argentina, Mederic; Mahadevan, Lakshminarayanan

    2014-11-01

    Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimeters to 30 meters, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming speed U to body kinematics (tail beat amplitude A and frequency ω) and fluid properties (kinematic viscosity ν). This principle can be simply couched as the power law Re ~ Swα , where Re = UL / ν >> 1 and Sw = ωAL / ν , with α = 4 / 3 for laminar flows, and α = 1 for turbulent flows. Existing data from over 1000 measurements on fish, amphibians, larvae, reptiles, mammals and birds, as well as direct numerical simulations are consistent with our scaling. We interpret our results as the consequence of the convergence of aquatic gaits to the performance limits imposed by hydrodynamics.

  8. Aquatic polymers can drive pathogen transmission in coastal ecosystems

    OpenAIRE

    Shapiro, Karen; Krusor, Colin; Mazzillo, Fernanda F. M.; Conrad, Patricia A.; Largier, John L.; Jonna A K Mazet; Silver, Mary W.

    2014-01-01

    Gelatinous polymers including extracellular polymeric substances (EPSs) are fundamental to biophysical processes in aquatic habitats, including mediating aggregation processes and functioning as the matrix of biofilms. Yet insight into the impact of these sticky molecules on the environmental transmission of pathogens in the ocean is limited. We used the zoonotic parasite Toxoplasma gondii as a model to evaluate polymer-mediated mechanisms that promote transmission of terrestrially derived pa...

  9. Invasive ornamental fish: a potential threat to aquatic biodiversity in peninsular India

    Directory of Open Access Journals (Sweden)

    J.D.M. Knight

    2010-02-01

    Full Text Available Alien fish find their way into newer habitats and ecosystems opportunistically. Once in a new habitat, these species try to occupy empty niches and compete with native species. An alien species becomes invasive wherever it has a competetive advantage over native species. Ecology of aquatic invasive alien species is rather poorly understood as most attention has been on invertebrates as that which spread through ballast water. Invasive alien species of fish that have taken advantage of the aquarium trade are emerging as the most important threats to fragile aquatic habitats. Regulations to this trade are rather weak and there is a general lack of data on the ecological impact of alien fish species despite the fact that a third of the world’s worst aquatic invasive species are aquarium or ornamental species.

  10. Ensemble forecasting of potential habitat for three invasive fishes

    Science.gov (United States)

    Poulos, Helen M.; Chernoff, Barry; Fuller, Pam L.; Butman, David

    2012-01-01

    Aquatic invasive species pose major ecological and economic threats to aquatic ecosystems worldwide via displacement, predation, or hybridization with native species and the alteration of aquatic habitats and hydrologic cycles. Modeling the habitat suitability of alien aquatic species through spatially explicit mapping is an increasingly important risk assessment tool. Habitat modeling also facilitates identification of key environmental variables influencing invasive species distributions. We compared four modeling methods to predict the potential continental United States distributions of northern snakehead Channa argus (Cantor, 1842), round goby Neogobius melanostomus (Pallas, 1814), and silver carp Hypophthalmichthys molitrix (Valenciennes, 1844) using maximum entropy (Maxent), the genetic algorithm for rule set production (GARP), DOMAIN, and support vector machines (SVM). We used inventory records from the USGS Nonindigenous Aquatic Species Database and a geographic information system of 20 climatic and environmental variables to generate individual and ensemble distribution maps for each species. The ensemble maps from our study performed as well as or better than all of the individual models except Maxent. The ensemble and Maxent models produced significantly higher accuracy individual maps than GARP, one-class SVMs, or DOMAIN. The key environmental predictor variables in the individual models were consistent with the tolerances of each species. Results from this study provide insights into which locations and environmental conditions may promote the future spread of invasive fish in the US.

  11. Reconstructing fish movements between coastal wetland and nearshore habitats of the Great Lakes

    Science.gov (United States)

    The use of resources from multiple habitats has been shown to be important to the production of aquatic consumers. To quantify the support of Great Lakes coastal wetland (WL) and nearshore (NS) habitats to yellow perch, we used otolith microchemistry to trace movements between th...

  12. Improving aquatic warbler population assessments by accounting for imperfect detection.

    Science.gov (United States)

    Oppel, Steffen; Marczakiewicz, Piotr; Lachmann, Lars; Grzywaczewski, Grzegorz

    2014-01-01

    Monitoring programs designed to assess changes in population size over time need to account for imperfect detection and provide estimates of precision around annual abundance estimates. Especially for species dependent on conservation management, robust monitoring is essential to evaluate the effectiveness of management. Many bird species of temperate grasslands depend on specific conservation management to maintain suitable breeding habitat. One such species is the Aquatic Warbler (Acrocephalus paludicola), which breeds in open fen mires in Central Europe. Aquatic Warbler populations have so far been assessed using a complete survey that aims to enumerate all singing males over a large area. Because this approach provides no estimate of precision and does not account for observation error, detecting moderate population changes is challenging. From 2011 to 2013 we trialled a new line transect sampling monitoring design in the Biebrza valley, Poland, to estimate abundance of singing male Aquatic Warblers. We surveyed Aquatic Warblers repeatedly along 50 randomly placed 1-km transects, and used binomial mixture models to estimate abundances per transect. The repeated line transect sampling required 150 observer days, and thus less effort than the traditional 'full count' approach (175 observer days). Aquatic Warbler abundance was highest at intermediate water levels, and detection probability varied between years and was influenced by vegetation height. A power analysis indicated that our line transect sampling design had a power of 68% to detect a 20% population change over 10 years, whereas raw count data had a 9% power to detect the same trend. Thus, by accounting for imperfect detection we increased the power to detect population changes. We recommend to adopt the repeated line transect sampling approach for monitoring Aquatic Warblers in Poland and in other important breeding areas to monitor changes in population size and the effects of habitat management.

  13. Improving aquatic warbler population assessments by accounting for imperfect detection.

    Directory of Open Access Journals (Sweden)

    Steffen Oppel

    Full Text Available Monitoring programs designed to assess changes in population size over time need to account for imperfect detection and provide estimates of precision around annual abundance estimates. Especially for species dependent on conservation management, robust monitoring is essential to evaluate the effectiveness of management. Many bird species of temperate grasslands depend on specific conservation management to maintain suitable breeding habitat. One such species is the Aquatic Warbler (Acrocephalus paludicola, which breeds in open fen mires in Central Europe. Aquatic Warbler populations have so far been assessed using a complete survey that aims to enumerate all singing males over a large area. Because this approach provides no estimate of precision and does not account for observation error, detecting moderate population changes is challenging. From 2011 to 2013 we trialled a new line transect sampling monitoring design in the Biebrza valley, Poland, to estimate abundance of singing male Aquatic Warblers. We surveyed Aquatic Warblers repeatedly along 50 randomly placed 1-km transects, and used binomial mixture models to estimate abundances per transect. The repeated line transect sampling required 150 observer days, and thus less effort than the traditional 'full count' approach (175 observer days. Aquatic Warbler abundance was highest at intermediate water levels, and detection probability varied between years and was influenced by vegetation height. A power analysis indicated that our line transect sampling design had a power of 68% to detect a 20% population change over 10 years, whereas raw count data had a 9% power to detect the same trend. Thus, by accounting for imperfect detection we increased the power to detect population changes. We recommend to adopt the repeated line transect sampling approach for monitoring Aquatic Warblers in Poland and in other important breeding areas to monitor changes in population size and the effects of

  14. An interpolation method for stream habitat assessments

    Science.gov (United States)

    Sheehan, Kenneth R.; Welsh, Stuart A.

    2015-01-01

    Interpolation of stream habitat can be very useful for habitat assessment. Using a small number of habitat samples to predict the habitat of larger areas can reduce time and labor costs as long as it provides accurate estimates of habitat. The spatial correlation of stream habitat variables such as substrate and depth improves the accuracy of interpolated data. Several geographical information system interpolation methods (natural neighbor, inverse distance weighted, ordinary kriging, spline, and universal kriging) were used to predict substrate and depth within a 210.7-m2 section of a second-order stream based on 2.5% and 5.0% sampling of the total area. Depth and substrate were recorded for the entire study site and compared with the interpolated values to determine the accuracy of the predictions. In all instances, the 5% interpolations were more accurate for both depth and substrate than the 2.5% interpolations, which achieved accuracies up to 95% and 92%, respectively. Interpolations of depth based on 2.5% sampling attained accuracies of 49–92%, whereas those based on 5% percent sampling attained accuracies of 57–95%. Natural neighbor interpolation was more accurate than that using the inverse distance weighted, ordinary kriging, spline, and universal kriging approaches. Our findings demonstrate the effective use of minimal amounts of small-scale data for the interpolation of habitat over large areas of a stream channel. Use of this method will provide time and cost savings in the assessment of large sections of rivers as well as functional maps to aid the habitat-based management of aquatic species.

  15. Western Alaska ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) in Western Alaska. Vector polygons in this data set represent...

  16. Columbia River ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV), rare plant species [Water howellia (Howelia aquatilis) and...

  17. Freshwater Ecosystems and Resilience of Pacific Salmon: Habitat Management Based on Natural Variability

    OpenAIRE

    Gordon H Reeves; Dunham, Jason B.; Bisson, Peter A.

    2009-01-01

    In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologically unsustainable conditions may partly explain this lack of response. Natural watershed process...

  18. Efficacy of trap modifications for increasing capture rates of aquatic snakes in floating aquatic funnel traps

    Science.gov (United States)

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2013-01-01

    Increasing detection and capture probabilities of rare or elusive herpetofauna of conservation concern is important to inform the scientific basis for their management and recovery. The Giant Gartersnake (Thamnophis gigas) is an example of a secretive, wary, and generally difficult-to-sample species about which little is known regarding its patterns of occurrence and demography. We therefore evaluated modifications to existing traps to increase the detection and capture probabilities of the Giant Gartersnake to improve the precision with which occurrence, abundance, survival, and other demographic parameters are estimated. We found that adding a one-way valve constructed of cable ties to the small funnel opening of traps and adding hardware cloth extensions to the wide end of funnels increased capture rates of the Giant Gartersnake by 5.55 times (95% credible interval = 2.45–10.51) relative to unmodified traps. The effectiveness of these modifications was insensitive to the aquatic habitat type in which they were deployed. The snout-vent length of the smallest and largest captured snakes did not vary among trap modifications. These trap modifications are expected to increase detection and capture probabilities of the Giant Gartersnake, and show promise for increasing the precision with which demographic parameters can be estimated for this species. We anticipate that the trap modifications found effective in this study will be applicable to a variety of aquatic and semi-aquatic reptiles and amphibians and improve conservation efforts for these species.

  19. Late cretaceous aquatic plant world in Patagonia, Argentina.

    Directory of Open Access Journals (Sweden)

    N Rubén Cúneo

    Full Text Available In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla and a monocot (Araceae. Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae. Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form and the eudicot angiosperm Nelumbo (Nelumbonaceae are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae, ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.

  20. Late cretaceous aquatic plant world in Patagonia, Argentina.

    Science.gov (United States)

    Cúneo, N Rubén; Gandolfo, María A; Zamaloa, María C; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America. PMID:25148081

  1. Marine invasions by non-sea snakes, with thoughts on terrestrial-aquatic-marine transitions.

    Science.gov (United States)

    Murphy, John C

    2012-08-01

    Few species of snakes show extensive adaptations to aquatic environments and even fewer exploit the oceans. A survey of morphology, lifestyles, and habitats of 2552 alethenophidian snakes revealed 362 (14%) that use aquatic environments, are semi-aquatic, or aquatic; about 70 (2.7%) of these are sea snakes (Hydrophiinae and Laticaudinae). The ancient and aquatic family Acrochordidae contains three extant species, all of which have populations inhabiting brackish or marine environments, as well as freshwater. The Homalopsidae have the most ecologically diverse representatives in coastal habitats. Other families containing species exploiting saline waters with populations in freshwater environments include: the Dipsadidae of the western hemisphere, the cosmopolitan Natricidae, the African Grayinae, and probably a few Colubridae. Species with aquatic and semi-aquatic lifestyles are compared with more terrestrial (fossorial, cryptozoic, and arboreal) species for morphological traits and life histories that are convergent with those found in sea snakes; this may provide clues to the evolution of marine snakes and increase our understanding of snake diversity.

  2. Conceptual Framework for Aquatic Interfaces

    Science.gov (United States)

    Lewandowski, J.; Krause, S.

    2015-12-01

    Aquatic interfaces are generally characterized by steep gradients of physical, chemical and biological properties due to the contrast between the two adjacent environments. Innovative measurement techniques are required to study the spatially heterogeneous and temporally variable processes. Especially the different spatial and temporal scales are a large challenge. Due to the steep biogeochemical gradients and the intensive structural and compositional heterogeneity, enhanced biogeochemical processing rates are inherent to aquatic interfaces. Nevertheless, the effective turnover depends strongly on the residence time distribution along the flow paths and in sections with particular biogeochemical milieus and reaction kinetics. Thus, identification and characterization of the highly complex flow patterns in and across aquatic interfaces are crucial to understand biogeochemical processing along exchange flow paths and to quantify transport across aquatic interfaces. Hydrodynamic and biogeochemical processes are closely coupled at aquatic interfaces. However, interface processing rates are not only enhanced compared to the adjacent compartments that they connect; also completely different reactions might occur if certain thresholds are exceeded or the biogeochemical milieu differs significantly from the adjacent environments. Single events, temporal variability and spatial heterogeneity might increase overall processing rates of aquatic interfaces and thus, should not be neglected when studying aquatic interfaces. Aquatic interfaces are key zones relevant for the ecological state of the entire ecosystem and thus, understanding interface functioning and controls is paramount for ecosystem management. The overall aim of this contribution is a general conceptual framework for aquatic interfaces that is applicable to a wide range of systems, scales and processes.

  3. Aquatic invertebrate communities in tank bromeliads: how well do classic ecological patterns apply?

    OpenAIRE

    Jocque, Merlijn; Field, Richard

    2014-01-01

    Tank bromeliads (Bromeliaceae) often occur in high densities in the Neotropics and represent a key freshwater habitat in montane forests, housing quite complex invertebrate communities. We tested the extent to which there are species richness–altitude, richness–environment, richness–size, richness–habitat complexity and richness–isolation relationships for the aquatic invertebrate communities from 157 bromeliads in Cusuco National Park, Honduras. We found that invertebrate species richness an...

  4. Contaminants in oil field produced waters discharged into the Loch Katrine Wetland Complex, Park County, Wyoming and their bioconcentration in the aquatic bird food chain

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The 866-acre Loch Katrine wetland complex in Park County, Wyoming provides habitat for many species of aquatic birds. However, the complex is sustained primarily by...

  5. Two-dimensional habitat modeling in the Yellowstone/Upper Missouri River system

    Science.gov (United States)

    Waddle, T. J.; Bovee, K.D.; Bowen, Z.H.

    1997-01-01

    This study is being conducted to provide the aquatic biology component of a decision support system being developed by the U.S. Bureau of Reclamation. In an attempt to capture the habitat needs of Great Plains fish communities we are looking beyond previous habitat modeling methods. Traditional habitat modeling approaches have relied on one-dimensional hydraulic models and lumped compositional habitat metrics to describe aquatic habitat. A broader range of habitat descriptors is available when both composition and configuration of habitats is considered. Habitat metrics that consider both composition and configuration can be adapted from terrestrial biology. These metrics are most conveniently accessed with spatially explicit descriptors of the physical variables driving habitat composition. Two-dimensional hydrodynamic models have advanced to the point that they may provide the spatially explicit description of physical parameters needed to address this problem. This paper reports progress to date on applying two-dimensional hydraulic and habitat models on the Yellowstone and Missouri Rivers and uses examples from the Yellowstone River to illustrate the configurational metrics as a new tool for assessing riverine habitats.

  6. Ohio Aquatic Gap Analysis-An Assessment of the Biodiversity and Conservation Status of Native Aquatic Animal Species

    Science.gov (United States)

    Covert, S. Alex; Kula, Stephanie P.; Simonson, Laura A.

    2007-01-01

    The goal of the GAP Analysis Program is to keep common species common by identifying those species and habitats that are not yet adequately represented in the existing matrix of conservation lands. The Gap Analysis Program (GAP) is sponsored by the Biological Resources Discipline of the U.S. Geological Survey (USGS). The Ohio Aquatic GAP (OH-GAP) is a pilot project that is applying the GAP concept to aquatic-specifically, riverine-data. The mission of GAP is to provide regional assessments of the conservation status of native animal species and to facilitate the application of this information to land-management activities. OH-GAP accomplished this through * mapping aquatic habitat types, * mapping the predicted distributions of fish, crayfish, and bivalves, * documenting the presence of aquatic species in areas managed for conservation, * providing GAP results to the public, planners, managers, policy makers, and researchers, and * building cooperation with multiple organizations to apply GAP results to state and regional management activities. Gap analysis is a coarse-scale assessment of aquatic biodiversity and conservation; the goal is to identify gaps in the conservation of native aquatic species. It is not a substitute for biological field studies and monitoring programs. Gap analysis was conducted for the continuously flowing streams in Ohio. Lakes, reservoirs, wetlands, and the Lake Erie islands were not included in this analysis. The streams in Ohio are in the Lake Erie and Ohio River watersheds and pass through six of the level III ecoregions defined by Omernik: the Eastern Corn Belt Plains, Southern Michigan/Northern Indiana Drift Plains, Huron/Erie Lake Plain, Erie Drift Plains, Interior Plateau, and the Western Allegheny Plateau. To characterize the aquatic habitats available to Ohio fish, crayfish, and bivalves, a classification system needed to be developed and mapped. The process of classification includes delineation of areas of relative

  7. Larvicidal activities of chinaberry, neem and Bacillus thuringiensis israelensis (Bti) to an insecticide resistant population of Anopheles arabiensis from Tolay, Southwest Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Assalif Demissew; Meshesha Balkew; Melaku Girma

    2016-01-01

    Objective: To elucidate the larvicidal potency of neem, chinaberry and Bacillus thur-ingiensis israelensis (Bti) to larvae of Anopheles arabiensis under semi-field condition and adult susceptibility/resistance to the conventionally used insecticides in Tolay, Southwestern Ethiopia. Methods: Wild collected 3rd and 4th stage larvae were exposed to neem, and chinaberry seed powder dissolved in water and Bti in artificial containers at three treatment levels:0.2, 0.1 and 0.05 g/m2 and controls were free of treatments. Larval and pupal mortalities were monitored daily and residual activities were determined. The experiments were replicated three times. The World Health Organization tube test for all classes of in-secticides was conducted on adult Anopheles arabiensis reared from field collected larvae and pupae. Data were analyzed using STATA software version 11. Results: In the first application, neem powder caused 88.9%, 87.9%and 79.4%larval and pupal mortality at 0.2, 0.1 and 0.05 g/m2 after 4.3, 6.0 and 5.7 days, respectively. The cor-responding killing effect of chinaberry was 80.3%, 62.1%and 30.3%after 7.0, 7.7 and 8.3 days respectively. Bti at all treatments killed 100%after 24 h except 2.7 days for 0.05 g/m2. Adult mosquitoes were susceptible only for fenitrothion and pirimiphos-methyl with 100%mortality while resistant to deltamethrin, alpha-cypermethrin, etofenprox and dichloro-diphenyl-tricgloroethane with only 9.0%, 3.0%, 5.1%and 2.0%mortalities respectively. Conclusions: Neem, chinaberry and Bti showed potent larvicidal and pupicidal activ-ities. However, in the area, high level of mosquito resistance to pyrethroids and dichloro-diphenyl-tricgloroethane was seen which will pose serious challenge to vector control in the future. Therefore, using integrated approach including these botanical larvicides is warranted to manage insecticide resistance.

  8. Predictive Seagrass Habitat Model

    Science.gov (United States)

    Restoration of ecosystem services provided by seagrass habitats in estuaries requires a firm understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We explored the application...

  9. EcologicHabitat_WCV

    Data.gov (United States)

    Vermont Center for Geographic Information — WCV describes the value of the Wildlife Habitat Suitability as it approaches the state highway system. This analysis was designed to use the Wildlife Habitat...

  10. Habitat monitoring plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Management of habitat is required in order to achieve the refuge purpose and wildlife objectives. The Upland Habitat Management Plan (1993, Interim Plan) and the...

  11. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  12. Aquatic insect assemblages associated with subalpine stream segment types in relict glaciated headwaters

    Science.gov (United States)

    Kubo, Joshua S.; Torgersen, Christian E.; Bolton, Susan M.; Weekes, Anne A.; Gara, Robert I.

    2013-01-01

    1. Aquatic habitats and biotic assemblages in subalpine headwaters are sensitive to climate and human impacts. Understanding biotic responses to such perturbations and the contribution of high-elevation headwaters to riverine biodiversity requires the assessment of assemblage composition among habitat types. We compared aquatic insect assemblages among headwater stream segment types in relict glaciated subalpine basins in Mt. Rainier National Park, Washington, USA. 2. Aquatic insects were collected during summer and autumn in three headwater basins. In each basin, three different stream segment types were sampled: colluvial groundwater sources, alluvial lake inlets, and cascade-bedrock lake outlets. Ward's hierarchical cluster analysis revealed high β diversity in aquatic insect assemblages, and non-metric multidimensional scaling indicated that spatial and temporal patterns in assemblage composition differed among headwater stream segment types. Aquatic insect assemblages showed more fidelity to stream segment types than to individual basins, and the principal environmental variables associated with assemblage structure were temperature and substrate. 3. Indicator species analyses identified specific aquatic insects associated with each stream segment type. Several rare and potentially endemic aquatic insect taxa were present, including the recently described species, Lednia borealis (Baumann and Kondratieff). 4. Our results indicate that aquatic insect assemblages in relict glaciated subalpine headwaters were strongly differentiated among stream segment types. These results illustrate the contribution of headwaters to riverine biodiversity and emphasise the importance of these habitats for monitoring biotic responses to climate change. Monitoring biotic assemblages in high-elevation headwaters is needed to prevent the potential loss of unique and sensitive biota.

  13. COMBINING CLIMATE MODEL PREDICTIONS, HYDROLOGICAL MODELING, AND ECOLOGICAL NICHE MODELING ALGORITHMS TO PREDICT THE IMPACTS OF CLIMATE CHANGE ON AQUATIC BIODIVERSITY

    Science.gov (United States)

    The results of this research will provide a broad taxonomic and regional assessment of the impacts of climate change on aquatic species in the United States by producing predictions of current and future habitat quality for aquatic taxa based on multiple climate change scen...

  14. Open, Sharable, and Extensible Data Management for the Korea National Aquatic Ecological Monitoring and Assessment Program: A RESTful API-Based Approach

    OpenAIRE

    Meilan Jiang; Karpjoo Jeong; Jung-Hwan Park; Nan-Young Kim; Soon-Jin Hwang; Sang-Hun Kim

    2016-01-01

    Implemented by a national law, the National Aquatic Ecological Monitoring Program (NAEMP) has been assessing the ecological health status of surface waters, focusing on streams and rivers, in Korea since 2007. The program involves ecological monitoring of multiple aquatic biota such as benthic diatoms, macroinvertebrates, fish, and plants as well as water quality and habitat parameters. Taking advantage of the national scale of long-term aquatic ecological monitoring and the standardization o...

  15. Exposures from aquatic pathways

    International Nuclear Information System (INIS)

    Methods for estimation aquatic pathways contribution to the total population exposure are discussed. Aquatic pathways are the major factor for radionuclides spreading from the Chernobyl Exclusion zone. An annual outflow of 90Sr and 137Cs comprised 10-20 TBq and 2-4 TBq respectively and the population exposed by this effluence constitutes almost 30 million people. The dynamic of doses from 90Sr and 'Cs, which Dnieper water have to delivered, is calculated. The special software has been developed to simulate the process of dose formation in the of diverse Dnieper regions. Regional peculiarities of municipal tap, fishing and irrigation are considered. Seventy-year prediction of dose structure and function of dose forming is performed. The exposure is estimated for 12 regions of the Dnieper basin and the Crimea. The maximal individual annual committed effective doses due to the use of water by ordinary members of the population in Kiev region from 90Sr and 137Cs in 1986 are 1.7*10-5 Sv and 2.7*10-5 Sv respectively. A commercial fisherman on Kiev reservoir in 1986 received 4.7*10-4 Sv and 5*10-3 Sv from 90Sr and 137Cs, respectively. The contributions to the collective cumulative (over 70 years) committed effective dose (CCCED70) of irrigation, municipal tap water and fish consumption for members of the population respectively are 18%, 43%, 39% in Kiev region, 8%, 25%, 67% in Poltava region, and 50%, 50%, 0% (consumption of Dnieper fish is absent) in the Crimea. The predicted contribution of the Strontium-90 to CCCED70 resulting from the use of water is 80%. The CCCED70 to the population of the Dnieper regions (32.5 million people) is 3000 person-Sv due to the use the Dnieper water

  16. Providing Aquatic Organism Passage in Vertically Unstable Streams

    Directory of Open Access Journals (Sweden)

    JanineM Castro

    2016-04-01

    Full Text Available Aquatic organism passage barriers have been identified as one of the key impediments to recovery of salmonids and other migratory aquatic organisms in the Pacific Northwest of the United States. As such, state and federal agencies invest millions of dollars annually to address passage barriers. Because many barriers function as ad hoc grade control structures, their removal and/or replacement can unwittingly set off a cascade of effects that can negatively impact the very habitat and passage that project proponents seek to improve. The resultant vertical instability can result in a suite of effects that range from floodplain disconnection and loss of backwater and side channel habitat, to increased levels of turbidity. Risk assessment, including an evaluation of both the stage of stream evolution and a longitudinal profile analysis, provides a framework for determining if grade control is warranted, and if so, what type of structure is most geomorphically appropriate. Potential structures include placement of large wood and roughness elements, and constructed riffles, step-pools, and cascades. The use of structure types that mimic natural reach scale geomorphic analogues should result in improved aquatic organism passage, increased structural resilience, and reduced maintenance.

  17. The Anopheles arabiensis genetic sexing strain ANO IPCL1 and its application potential for the sterile insect technique in integrated vector management programmes.

    Science.gov (United States)

    Yamada, Hanano; Vreysen, Marc J B; Bourtzis, Kostas; Tschirk, Wolfgang; Chadee, Dave D; Gilles, Jeremie R L

    2015-02-01

    The Anopheles arabiensis genetic sexing strain ANO IPCL1 was developed based on a dieldrin resistant mutation. The strain has been shown to be practical and reliable in terms of female elimination by dieldrin treatments at larval stages, but has provided some difficulties when treatments were applied at the egg stage. The high natural sterility of this strain has advantages and disadvantages in both mass rearing and the sterilization process. In addition, its recombination rate, although relatively low, poses a threat of strain deterioration if left unchecked in a mass-rearing setting. The males of the ANO IPCL1 have been shown to be equally competitive as lab-reared males of the wild-type Dongola strain, but competitiveness decreased by half when irradiated with 75 Gy—a dose conferring >98% sterility. More controversial issues surround the use of dieldrin—a highly persistent organochlorine that is known to bioaccumulate in the food chain. The prospective use of large volumes of dieldrin in a mass-rearing facility and the retention of its residues by the male mosquitoes makes the use of the strain in the context of the sterile insect technique against this vector highly questionable, and therefore its implementation at a large scale cannot be recommended. PMID:25438257

  18. Synthesis and antimosquito properties of 2,6-substituted benzo[d]thiazole and 2,4-substituted benzo[d]thiazole analogues against Anopheles arabiensis.

    Science.gov (United States)

    Venugopala, Katharigatta Narayanaswamy; Krishnappa, Manjula; Nayak, Susanta K; Subrahmanya, Bhat K; Vaderapura, Jayashankaragowda P; Chalannavar, Raju K; Gleiser, Raquel M; Odhav, Bharti

    2013-07-01

    A novel and efficient one pot synthesis was developed for 2,6-substituted-benzo[d]thiazole analogues 4a-k and 2,4-substituted-benzo[d]thiazole analogues 4l-pvia three component condensation reaction of substituted arylaldehyde, 2-amino-6-halo/4-methyl-benzo[d]thiazole and 2-naphthol or 6-hydroxyquinoline in presence of 10% w/v NaCl in water by microwave method. This method enabled for short reaction times, easy work-up and significant high yields. The title compound 4b was used for single crystal X-ray studies in order to understand its conformation and packing features. The title compounds 4a-p were screened for antimosquito properties such as repellency, insecticidal and larvicidal activity against Anopheles arabiensis by mosquito feeding-probing assay, cone bio-assay and standard WHO larvicidal assay, respectively. Among these analogous 4b, 4d and 4p exhibit the highest repellent activity comparable to the positive control DEET, and 4a and 4k knockdown most mosquitoes on repellent assays.

  19. Field investigation on the repellent activity of some aromatic plants by traditional means against Anopheles arabiensis and An. pharoensis (Diptera: Culicidae) around Koka, central Ethiopia.

    Science.gov (United States)

    Dugassa, Sisay; Medhin, Girmay; Balkew, Meshesha; Seyoum, Aklilu; Gebre-Michael, Teshome

    2009-10-01

    A study was undertaken to evaluate the impact of traditional application methods of mosquito repellent plants in the reduction of the human-vector contact of malaria vectors in central Ethiopia. The plants (Corymbia citriodora, Eucalyptus camaldulensis, Ocimum suave and Ocimum basilicum) were tested by thermal expulsion and direct burning on traditional stoves in the field against two important malaria vectors in Ethiopia (Anopheles arabiensis and An. pharoensis). A Latin-square design was applied for randomly assigning the treatment plants and control to experimental houses over different nights. The percentage repellency of each candidate plant by both application methods was estimated from the catches of mosquitoes in the treatment and control houses. On direct burning of the plants, O. basilicum showed the highest percentage repellency (73.11%, Pcitriodora on the other hand gave the highest repellency (72.87%, Pcitriodora exhibited the highest repellency (78.69%, Pcitriodora gave the highest repellency (72.9%, P65%) against the house-entry and biting of two important malaria vectors in Ethiopia, and thus have a potential to be used at least as supplements to other control methods. However, feasibility and actual impact on disease transmission need to be known on these and other potentially useful plants. PMID:19539591

  20. North Slope, Alaska ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats for the North Slope of Alaska. Vector polygons in this data set represent...

  1. Aquatic biodiversity in forests: A weak link in ecosystem services resilience

    Science.gov (United States)

    Penaluna, Brooke E.; Olson, Deanna H.; Flitcroft, Rebecca L; Weber, Matthew A.; Bellmore, James R.; Wondzell, Steven M.; Dunham, Jason; Johnson, Sherri L.; Reeves, Gordon H.

    2016-01-01

    The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in forests in natural systems and how they change with a variety of natural disturbances and human-derived stressors. We consider forested aquatic ecosystems as a multi-state portfolio, with diverse assemblages and life-history strategies occurring at local scales as a consequence of a mosaic of habitat conditions and past disturbances and stressors. Maintaining this multi-state portfolio of assemblages requires a broad perspective of ecosystem structure, various functions, services, and management implications relative to contemporary stressors. Because aquatic biodiversity provides multiple ecosystem services to forests, activities that compromise aquatic ecosystems and biodiversity could be an issue for maintaining forest ecosystem integrity. We illustrate these concepts with examples of aquatic biodiversity and ecosystem services in forests of northwestern North America, also known as Northeast Pacific Rim. Encouraging management planning at broad as well as local spatial scales to recognize multi-state ecosystem management goals has promise for maintaining valuable ecosystem services. Ultimately, integration of information from socio-ecological ecosystems will be needed to maintain ecosystem services derived directly and indirectly from forest aquatic biota.

  2. Modeling habitat split: landscape and life history traits determine amphibian extinction thresholds.

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Fonseca

    Full Text Available Habitat split is a major force behind the worldwide decline of amphibian populations, causing community change in richness and species composition. In fragmented landscapes, natural remnants, the terrestrial habitat of the adults, are frequently separated from streams, the aquatic habitat of the larvae. An important question is how this landscape configuration affects population levels and if it can drive species to extinction locally. Here, we put forward the first theoretical model on habitat split which is particularly concerned on how split distance - the distance between the two required habitats - affects population size and persistence in isolated fragments. Our diffusive model shows that habitat split alone is able to generate extinction thresholds. Fragments occurring between the aquatic habitat and a given critical split distance are expected to hold viable populations, while fragments located farther away are expected to be unoccupied. Species with higher reproductive success and higher diffusion rate of post-metamorphic youngs are expected to have farther critical split distances. Furthermore, the model indicates that negative effects of habitat split are poorly compensated by positive effects of fragment size. The habitat split model improves our understanding about spatially structured populations and has relevant implications for landscape design for conservation. It puts on a firm theoretical basis the relation between habitat split and the decline of amphibian populations.

  3. Evaluating the potential of the sterile insect technique for malaria control: relative fitness and mating compatibility between laboratory colonized and a wild population of Anopheles arabiensis from the Kruger National Park, South Africa

    Directory of Open Access Journals (Sweden)

    Hunt Richard H

    2011-10-01

    Full Text Available Abstract Background The successful suppression of a target insect population using the sterile insect technique (SIT partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them from successfully competing for mates in the wild. This study investigated the fitness and sexual cross-compatibility between samples of field collected and laboratory reared An. arabiensis under laboratory conditions. Results The physiological and reproductive fitness of the MALPAN laboratory strain is not substantially modified with respect to the field population at Malahlapanga. Further, a high degree of mating compatibility between MALPAN and the Malahlapanga population was established based on cross-mating experiments. Lastly, the morphological characteristics of hybrid ovarian polytene chromosomes further support the contention that the MALPAN laboratory colony and the An. arabiensis population at Malahlapanga are genetically homogenous and therefore compatible. Conclusions It is concluded that the presence of a perennial and isolated population of An. arabiensis at Malahlapanga presents a unique opportunity for assessing the feasibility of SIT as a malaria vector control option. The MALPAN laboratory colony has retained sufficient enough measures of reproductive and physiological fitness to present as a suitable candidate for male sterilization, mass rearing and subsequent mass release of sterile males at Malahlapanga in order to further assess the feasibility of SIT in a field setting.

  4. Tunison Laboratory of Aquatic Science

    Data.gov (United States)

    Federal Laboratory Consortium — Tunison Laboratory of Aquatic Science (TLAS), located in Cortland, New York, is a field station of the USGS Great Lakes Science Center (GLSC). TLAS was established...

  5. Role Models in Aquatic Occupations.

    Science.gov (United States)

    Brown, Mabel C.

    1982-01-01

    Provided for each of 12 minority group role models in aquatic occupations are job responsibilities, educational requirements, comments on a typical day at the job, salary range, and recommendations for students wishing to enter the field described. (JN)

  6. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate.

  7. Shorebird Habitat Suitability Indicies

    Data.gov (United States)

    Arctic Landscape Conservation Cooperative — This dataset consists of predicted habitat suitability indices and species richness for eight shorebird species (Black-bellied Plover [Pluvialis squatarola],...

  8. Amazonian freshwater habitats experiencing environmental and socioeconomic threats affecting subsistence fisheries

    OpenAIRE

    Cleber J. R. Alho; Roberto E. Reis; Aquino, Pedro P. U.

    2015-01-01

    Matching the trend seen among the major large rivers of the globe, the Amazon River and its tributaries are facing aquatic ecosystem disruption that is affecting freshwater habitats and their associated biodiversity, including trends for decline in fishery resources. The Amazon’s aquatic ecosystems, linked natural resources, and human communities that depend on them are increasingly at risk from a number of identified threats, including expansion of agriculture; cattle pastures; infrastructur...

  9. Mining of unexplored habitats for novel chitinases - chiA as a helper gene proxy in metagenomics

    DEFF Research Database (Denmark)

    Cretoiu, Mariana Silvia; Kielak, Anna Maria; Abu Al-Soud, Waleed;

    2012-01-01

    The main objective of this study was to assess the abundance and diversity of chitin-degrading microbial communities in ten terrestrial and aquatic habitats in order to provide guidance to the subsequent exploration of such environments for novel chitinolytic enzymes. A combined protocol which en...... habitats for subsequent bioexploration. Thus, the screening strategy used is proposed as a guide for further metagenomics-based exploration of the selected habitats....

  10. Evaluation of seven aquatic sampling methods for amphibians and other aquatic fauna

    Science.gov (United States)

    Gunzburger, M.S.

    2007-01-01

    To design effective and efficient research and monitoring programs researchers must have a thorough understanding of the capabilities and limitations of their sampling methods. Few direct comparative studies exist for aquatic sampling methods for amphibians. The objective of this study was to simultaneously employ seven aquatic sampling methods in 10 wetlands to compare amphibian species richness and number of individuals detected with each method. Four sampling methods allowed counts of individuals (metal dipnet, D-frame dipnet, box trap, crayfish trap), whereas the other three methods allowed detection of species (visual encounter, aural, and froglogger). Amphibian species richness was greatest with froglogger, box trap, and aural samples. For anuran species, the sampling methods by which each life stage was detected was related to relative length of larval and breeding periods and tadpole size. Detection probability of amphibians varied across sampling methods. Box trap sampling resulted in the most precise amphibian count, but the precision of all four count-based methods was low (coefficient of variation > 145 for all methods). The efficacy of the four count sampling methods at sampling fish and aquatic invertebrates was also analyzed because these predatory taxa are known to be important predictors of amphibian habitat distribution. Species richness and counts were similar for fish with the four methods, whereas invertebrate species richness and counts were greatest in box traps. An effective wetland amphibian monitoring program in the southeastern United States should include multiple sampling methods to obtain the most accurate assessment of species community composition at each site. The combined use of frogloggers, crayfish traps, and dipnets may be the most efficient and effective amphibian monitoring protocol. ?? 2007 Brill Academic Publishers.

  11. Nitrogen and protein contents in some aquatic plant species

    Directory of Open Access Journals (Sweden)

    Krystyna Bytniewska

    2015-05-01

    Full Text Available Nitrogen and protein contents in higher aquatic plants deriving from a natural habitat were determined. The following plants were examined: Spirodela polyrrhiza (L. Schleid., Elodea canadensis Rich., Riccia fluitans L. Total nitrogen and nitrogen of respective fractions were determined by the Kjeldahl method. Nitrogen compounds were fractionated according to Thimann et al. Protein was extracted after Fletcher and Osborne and fractionated after Osborne. It was found, that total protein content in the plants under examination constitutes 18 to 25%o of dry matter. Albumins and glutelins are the most abundant protein fractions.

  12. NOAA Office for Coastal Management and Maine Department of Marine Resources Benthic Habitat Data, coastal Maine and York and Webhannet rivers, 1993-2001 (NODC Accession 0089462)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Maine's eelgrass (SAV) meadows form an important aquatic habitat for the state. These meadows provide shelter for juvenile fish, and invertebrates. In certain...

  13. Solar energy development and aquatic ecosystems in the southwestern United States: potential impacts, mitigation, and research needs.

    Science.gov (United States)

    Grippo, Mark; Hayse, John W; O'Connor, Ben L

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface-groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  14. Solar Energy Development and Aquatic Ecosystems in the Southwestern United States: Potential Impacts, Mitigation, and Research Needs

    Science.gov (United States)

    Grippo, Mark; Hayse, John W.; O'Connor, Ben L.

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface-groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  15. Spatial repellency of transfluthrin-treated hessian strips against laboratory-reared Anopheles arabiensis mosquitoes in a semi-field tunnel cage

    Directory of Open Access Journals (Sweden)

    Ogoma Sheila B

    2012-03-01

    Full Text Available Abstract Background Vapour phase spatial repellents deter mosquitoes from attacking one or more humans in a protected space. Simulation models indicate that high coverage of spatial repellents can enhance the impact of long - lasting insecticide nets (LLINs and indoor residual spraying (IRS where mosquito vectors commonly bite humans outdoors. Here we report a preliminary evaluation of an effective, user-friendly prototype product for delivering spatial repellents to protect against malaria vector mosquitoes. Findings Protective efficacy of a 4.0 × 0.3 m strip of hessian sacking treated with 10 ml of transfluthrin was evaluated in a 60 m × 2 m ×2.5 m netting tunnel with malaria-free insectary-reared Anopheles arabiensis Patton mosquitoes. Personal protection, in terms of proportional reduction of exposure to bites, was measured by comparing human landing catches of volunteers with treated and untreated strips. A freshly treated hessian strip reduced mosquito attack rate on human volunteers by > 99% and consistently conferred > 90% protective efficacy for a period of 6 months. Over the entire study period, only 22 out of 1400 released mosquitoes bit volunteers using the treated sacking strip while 894 out of 1400 mosquitoes released into cages containing volunteers using an untreated strip fed upon them. Conclusion Locally available natural fibers may be promising absorbent substrates for delivering spatial repellents, such as transfluthrin, to protect against mosquitoes in tropical settings. However, these observations relate to a single prototype specimen of this particular device, therefore, much more detailed, well replicated studies are essential to establish long-term efficacy, effectiveness, practicability and affordability.

  16. Prolonged Colonisation, Irradiation, and Transportation do not Impede Mating Vigour and Competitiveness of Male Anopheles arabiensis Mosquitoes under Semifield Conditions in Northern Sudan

    International Nuclear Information System (INIS)

    Background. In Sudan, the Sterile Insect Technique (SIT) is being developed to suppress populations of Anopheles arabiensis. The present study was carried out to evaluate the impact of long-term colonisation, irradiation, and transportation on male vigour and mating competitiveness under controlled semi-field conditions. Materials and Methods. Male mosquitoes were irradiated in Khartoum as pupae and transported 400 km to the field site in Dongola. Wild males and females were collected as immature stages (larvae and pupae) from the field site and sexed immediately after adult emergence. Competition experiments were carried out to test the mating competitiveness and vigour of colonised males (non-irradiated or irradiated) against wild conspecifics in the semi-field system. Results. Mortality resulting from packaging and transportation from Khartoum to Dongola was low for adults (1.1% for irradiated and 1.3% for non-irradiated males). In contrast, all irradiated pupae died on their way to the field site. On average, 54.9% females were inseminated after one night. There were no differences between the number of females inseminated by colony males and those inseminated by wild males. Only a slightly significant difference between the numbers of females inseminated by irradiated males (14.0±1.7) or by wild males (19.7±1.7) was observed. However, the competitive index (CI) for irradiated and colony males when competed with wild males were 0.71 and 0.81 respectively. Conclusions. Packing and transportation methods for pupae need to be improved. Prolonged colonisation (68 generations), irradiation and transportation of adult males did not affect their ability to locate virgin females and compete against wild conspecifics. Irradiation, in contrast to many reports, only had a marginal effect on released males during the first night after their release. These findings support the feasibility of staging an SIT campaign against this malaria vector. (author)

  17. Dining dichotomy: aquatic and terrestrial prey capture behavior in the Himalayan newt Tylototriton verrucosus

    Science.gov (United States)

    De Vylder, Marie

    2016-01-01

    ABSTRACT Transitions between aquatic and terrestrial prey capture are challenging. Trophic shifts demand a high degree of behavioral flexibility to account for different physical circumstances between water and air to keep performance in both environments. The Himalayan newt, Tylototriton verrucosus, is mostly terrestrial but becomes aquatic during its short breeding period. Nonetheless, it was assumed that it lacks the capability of trophic behavioral flexibility, only captures prey on land by its tongue (lingual prehension) and does not feed in water. This theory was challenged from stomach content analyses in wild populations that found a variety of aquatic invertebrates in the newts' stomachs during their breeding season. Accordingly, we hypothesized that T. verrucosus actively changes its terrestrial prey capture mechanism to hunt for aquatic prey at least during its aquatic stage. In fact, the kinematic analyses showed that T. verrucosus uses lingual prehension to capture prey on land but changes to suction feeding for aquatic strikes. The statistical analyses revealed that terrestrial and aquatic strikes differ significantly in most kinematic parameters while behavioral variability does not differ between both behaviors. In turn, the movement patterns in suction feeding showed a higher degree of coordination between jaw and hyoid movements compared to the putative primary feeding mode, namely lingual prehension. We conclude that T. verrucosus, though relatively slow compared to trophic specialists, benefits from a high degree of behavioral flexibility that allows exploiting food sources efficiently from two very different habitats. PMID:27612510

  18. Ecological values of shallow-water habitats: Implications for the restoration of disturbed ecosystems

    Science.gov (United States)

    Lopez, C.B.; Cloern, J.E.; Schraga, T.S.; Little, A.J.; Lucas, L.V.; Thompson, J.K.; Burau, J.R.

    2006-01-01

    A presumed value of shallow-habitat enhanced pelagic productivity derives from the principle that in nutrient-rich aquatic systems phytoplankton growth rate is controlled by light availability, which varies inversely with habitat depth. We measured a set of biological indicators across the gradient of habitat depth within the Sacramento-San Joaquin River Delta (California) to test the hypothesis that plankton biomass, production, and pelagic energy flow also vary systematically with habitat depth. Results showed that phytoplankton biomass and production were only weakly related to phytoplankton growth rates whereas other processes (transport, consumption) were important controls. Distribution of the invasive clam Corbicula fluminea was patchy, and heavily colonized habitats all supported low phytoplankton biomass and production and functioned as food sinks. Surplus primary production in shallow, uncolonized habitats provided potential subsidies to neighboring recipient habitats. Zooplankton in deeper habitats, where grazing exceeded phytoplankton production, were likely supported by significant fluxes of phytoplankton biomass from connected donor habitats. Our results provide three important lessons for ecosystem science: (a) in the absence of process measurements, derived indices provide valuable information to improve our mechanistic understanding of ecosystem function and to benefit adaptive management strategies; (b) the benefits of some ecosystem functions are displaced by water movements, so the value of individual habitat types can only be revealed through a regional perspective that includes connectedness among habitats; and (c) invasive species can act as overriding controls of habitat function, adding to the uncertainty of management outcomes. ?? 2006 Springer Science+Business Media, Inc.

  19. Advanced Plant Habitat (APH)

    Science.gov (United States)

    Richards, Stephanie E. (Compiler); Levine, Howard G.; Reed, David W.

    2016-01-01

    The Advanced Plant Habitat (APH) hardware will be a large growth volume plant habitat, capable of hosting multigenerational studies, in which environmental variables (e.g., temperature, relative humidity, carbon dioxide level light intensity and spectral quality) can be tracked and controlled in support of whole plant physiological testing and Bio-regenerative Life Support System investigations.

  20. Behavioural cues surpass habitat factors in explaining prebreeding resource selection by a migratory diving duck

    Science.gov (United States)

    O'Neil, Shawn T.; Warren, Jeffrey M.; Takekawa, John Y.; De La Cruz, Susan E. W.; Cutting, Kyle A.; Parker, Michael W.; Yee, Julie L.

    2014-01-01

    Prebreeding habitat selection in birds can often be explained in part by habitat characteristics. However, females may also select habitats on the basis of fidelity to areas of previous reproductive success or use by conspecifics. The relative influences of sociobehavioural attributes versus habitat characteristics in habitat selection has been primarily investigated in songbirds, while less is known about how these factors affect habitat selection processes in migratory waterfowl. Animal resource selection models often exhibit much unexplained variation; spatial patterns driven by social and behavioural characteristics may account for some of this. We radiomarked female lesser scaup, Aythya affinis, in the southwestern extent of their breeding range to explore hypotheses regarding relative roles of habitat quality, site fidelity and conspecific density in prebreeding habitat selection. We used linear mixed-effects models to relate intensity of use within female home ranges to habitat features, distance to areas of reproductive success during the previous breeding season and conspecific density. Home range habitats included shallow water (≤118 cm), moderate to high densities of flooded emergent vegetation/open water edge and open water areas with submerged aquatic vegetation. Compared with habitat features, conspecific female density and proximity to successful nesting habitats from the previous breeding season had greater influences on habitat use within home ranges. Fidelity and conspecific attraction are behavioural characteristics in some waterfowl species that may exert a greater influence than habitat features in influencing prebreeding space use and habitat selection within home ranges, particularly where quality habitat is abundant. These processes may be of critical importance to a better understanding of habitat selection in breeding birds.

  1. Habitat stability and occurrences of malaria vector larvae in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Atieli Harrysone

    2009-10-01

    Full Text Available Abstract Background Although the occurrence of malaria vector larvae in the valleys of western Kenya highlands is well documented, knowledge of larval habitats in the uphill sites is lacking. Given that most inhabitants of the highlands actually dwell in the uphill regions, it is important to develop understanding of mosquito breeding habitat stability in these sites in order to determine their potential for larval control. Methods A total of 128 potential larval habitats were identified in hilltops and along the seasonal streams in the Sigalagala area of Kakamega district, western Kenya. Water availability in the habitats was followed up daily from August 3, 2006 to February 23, 2007. A habitat is defined as stable when it remains aquatic continuously for at least 12 d. Mosquito larvae were observed weekly. Frequencies of aquatic, stable and larvae positive habitats were compared between the hilltop and seasonal stream area using χ2-test. Factors affecting the presence/absence of Anopheles gambiae larvae in the highlands were determined using multiple logistic regression analysis. Results Topography significantly affected habitat availability and stability. The occurrence of aquatic habitats in the hilltop was more sporadic than in the stream area. The percentage of habitat occurrences that were classified as stable during the rainy season is 48.76% and 80.79% respectively for the hilltop and stream area. Corresponding frequencies of larvae positive habitats were 0% in the hilltop and 5.91% in the stream area. After the rainy season, only 23.42% of habitat occurrences were stable and 0.01% larvae positive habitats were found in the hilltops, whereas 89.75% of occurrences remained stable in the stream area resulting in a frequency of 12.21% larvae positive habitats. The logistic regression analysis confirmed the association between habitat stability and larval occurrence and indicated that habitat surface area was negatively affecting the

  2. Cone visual pigments of aquatic mammals.

    Science.gov (United States)

    Newman, Lucy A; Robinson, Phyllis R

    2005-01-01

    It has long been hypothesized that the visual systems of animals are evolutionarily adapted to their visual environment. The entrance many millions of years ago of mammals into the sea gave these new aquatic mammals completely novel visual surroundings with respect to light availability and predominant wavelengths. This study examines the cone opsins of marine mammals, hypothesizing, based on previous studies [Fasick et al. (1998) and Levenson & Dizon (2003)], that the deep-dwelling marine mammals would not have color vision because the pressure to maintain color vision in the dark monochromatic ocean environment has been relaxed. Short-wavelength-sensitive (SWS) and long-wavelength-sensitive (LWS) cone opsin genes from two orders (Cetacea and Sirenia) and an additional suborder (Pinnipedia) of aquatic mammals were amplified from genomic DNA (for SWS) and cDNA (for LWS) by PCR, cloned, and sequenced. All animals studied from the order Cetacea have SWS pseudogenes, whereas a representative from the order Sirenia has an intact SWS gene, for which the corresponding mRNA was found in the retina. One of the pinnipeds studied (harp seal) has an SWS pseudogene, while another species (harbor seal) appeared to have an intact SWS gene. However, no SWS cone opsin mRNA was found in the harbor seal retina, suggesting a promoter or splice site mutation preventing transcription of the gene. The LWS opsins from the different species were expressed in mammalian cells and reconstituted with the 11-cis-retinal chromophore in order to determine maximal absorption wavelengths (lambda(max)) for each. The deeper dwelling Cetacean species had blue shifted lambda(max) values compared to shallower-dwelling aquatic species. Taken together, these findings support the hypothesis that in the monochromatic oceanic habitat, the pressure to maintain color vision has been relaxed and mutations are retained in the SWS genes, resulting in pseudogenes. Additionally, LWS opsins are retained in the

  3. Widespread and persistent invasions of terrestrial habitats coincident with larval feeding behavior transitions during snail-killing fly evolution (Diptera: Sciomyzidae

    Directory of Open Access Journals (Sweden)

    Chapman Eric G

    2012-09-01

    Full Text Available Abstract Background Transitions in habitats and feeding behaviors were fundamental to the diversification of life on Earth. There is ongoing debate regarding the typical directionality of transitions between aquatic and terrestrial habitats and the mechanisms responsible for the preponderance of terrestrial to aquatic transitions. Snail-killing flies (Diptera: Sciomyzidae represent an excellent model system to study such transitions because their larvae display a range of feeding behaviors, being predators, parasitoids or saprophages of a variety of mollusks in freshwater, shoreline and dry terrestrial habitats. The remarkable genus Tetanocera (Tetanocerini occupies five larval feeding groups and all of the habitat types mentioned above. This study has four principal objectives: (i construct a robust estimate of phylogeny for Tetanocera and Tetanocerini, (ii estimate the evolutionary transitions in larval feeding behaviors and habitats, (iii test the monophyly of feeding groups and (iv identify mechanisms underlying sciomyzid habitat and feeding behavior evolution. Results Bayesian inference and maximum likelihood analyses of molecular data provided strong support that the Sciomyzini, Tetanocerini and Tetanocera are monophyletic. However, the monophyly of many behavioral groupings was rejected via phylogenetic constraint analyses. We determined that (i the ancestral sciomyzid lineage was terrestrial, (ii there was a single terrestrial to aquatic habitat transition early in the evolution of the Tetanocerini and (iii there were at least 10 independent aquatic to terrestrial habitat transitions and at least 15 feeding behavior transitions during tetanocerine phylogenesis. The ancestor of Tetanocera was aquatic with five lineages making independent transitions to terrestrial habitats and seven making independent transitions in feeding behaviors. Conclusions The preponderance of aquatic to terrestrial transitions in sciomyzids goes against the trend

  4. Aquatic risk assessment of pesticides in Latin America.

    Science.gov (United States)

    Carriquiriborde, Pedro; Mirabella, Paula; Waichman, Andrea; Solomon, Keith; Van den Brink, Paul J; Maund, Steve

    2014-10-01

    Latin America is anticipated to be a major growth market for agriculture and production is increasing with use of technologies such as pesticides. Reports of contamination of aquatic ecosystems by pesticides in Latin America have raised concerns about potential for adverse ecological effects. In the registration process of pesticides, all countries require significant data packages on aquatic toxicology and environmental fate. However, there are usually no specific requirements to conduct an aquatic risk assessment. To address this issue, the Society of Environmental Toxicology and Chemistry organized a workshop that brought together scientists from academia, government, and industry to review and elaborate on aquatic risk assessment frameworks that can be implemented into regulation of pesticides in Latin America. The workshop concluded that the international framework for risk assessments (protection goals, effects, and exposure assessments, risk characterization, and risk mitigation) is broadly applicable in Latin America but needs further refinement for the use in the region. Some of the challenges associated with these refinements are discussed in the article. It was recognized that there is potential for data sharing both within and outside of the region where conditions are similar. However, there is a need for research to compare local species and environmental conditions to those in other jurisdictions to be able to evaluate the applicability of data used in other countries. Development should also focus on human resources as there is a need to build local capacity and capability, and scientific collaboration and exchange between stakeholders in industry, government, and academia is also important. The meeting also emphasized that, although establishing a regionally relevant risk assessment framework is important, this also needs to be accompanied by enforcement of developed regulations and good management practices to help protect aquatic habitats

  5. A habitat-use model to determine essential fish habitat for juvenile brown shrimp (Farfantepenaeus aztecus) in Galveston Bay, Texas

    OpenAIRE

    Clark, Randall D.; Christensen, John D.; Mark E Monaco; Caldwell, Philip A.; Matthews, Geoffrey A.; Minello , Thomas J.

    2004-01-01

    A density prediction model for juvenile brown shrimp (Farfantepenaeus aztecus) was developed by using three bottom types, five salinity zones, and four seasons to quantify patterns of habitat use in Galveston Bay, Texas. Sixteen years of quantitative density data were used. Bottom types were vegetated marsh edge, submerged aquatic vegetation, and shallow nonvegetated bottom. Multiple regression was used to develop density estimates, and the resultant formula was then coupled with a geographic...

  6. Wildfire may increase habitat quality for spring Chinook salmon in the Wenatchee River subbasin, WA, USA

    Science.gov (United States)

    Flitcroft, Rebecca L; Falke, Jeffrey A.; Reeves, Gordon H.; Hessburg, Paul F.; McNyset, Kris M.; Benda, Lee E.

    2016-01-01

    Pacific Northwest salmonids are adapted to natural disturbance regimes that create dynamic habitat patterns over space and through time. However, human land use, particularly long-term fire suppression, has altered the intensity and frequency of wildfire in forested upland and riparian areas. To examine the potential impacts of wildfire on aquatic systems, we developed stream-reach-scale models of freshwater habitat for three life stages (adult, egg/fry, and juvenile) of spring Chinook salmon (Oncorhynchus tshawytscha) in the Wenatchee River subbasin, Washington. We used variables representing pre- and post-fire habitat conditions and employed novel techniques to capture changes in in-stream fine sediment, wood, and water temperature. Watershed-scale comparisons of high-quality habitat for each life stage of spring Chinook salmon habitat suggested that there are smaller quantities of high-quality juvenile overwinter habitat as compared to habitat for other life stages. We found that wildfire has the potential to increase quality of adult and overwintering juvenile habitat through increased delivery of wood, while decreasing the quality of egg and fry habitat due to the introduction of fine sediments. Model results showed the largest effect of fire on habitat quality associated with the juvenile life stage, resulting in increases in high-quality habitat in all watersheds. Due to the limited availability of pre-fire high-quality juvenile habitat, and increased habitat quality for this life stage post-fire, occurrence of characteristic wildfires would likely create a positive effect on spring Chinook salmon habitat in the Wenatchee River subbasin. We also compared pre- and post-fire model results of freshwater habitat for each life stage, and for the geometric mean of habitat quality across all life stages, using current compared to the historic distribution of spring Chinook salmon. We found that spring Chinook salmon are currently distributed in stream channels in

  7. Tritium in the aquatic environment

    International Nuclear Information System (INIS)

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products

  8. Tritium in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products.

  9. Freshwater habitats in Plovdiv town and its surroundings and their importance for the biodiversity

    Directory of Open Access Journals (Sweden)

    DILYAN GEORGIEV

    2015-08-01

    Full Text Available The current synopsis reviews the types of aquatic habitats, that are located in the city of Plovdiv and analyses their importance for the biodiversity. Studies of the biodiversity in urban landscapes are of particular importance because they are still scarce. Several plant and animal groups are studied in the city of Plovdiv – mosses, mollusks, fish, amphibians, reptiles, birds and mammals. Their distribution among habitats is presented, as well as specific threats and conservation problems.

  10. Lissotriton vulgaris paedomorphs in south-western Romania: a consequence of a human modified habitat ?

    Directory of Open Access Journals (Sweden)

    Severus-Daniel Covaciu-Marcov

    2011-06-01

    Full Text Available A Lissotriton vulgaris paedomorph population was identified for the first time ever in south-western Romania. The occurrence of this paedomorphosis is explained by the particularities of the area, the newts inhabiting a permanent but artificial habitat, surrounded by agricultural fields. Thus, the presence of an acceptable aquatic habitat together with the absence of a suitable terrestrial one triggered the occurrence of paedomorphosis.

  11. Terrestrial habitat use by western pond turtles (Actinemys marmorata) in the sierra foothills

    OpenAIRE

    Zaragoza, G; Rose, JP; Purcell, K; Todd, BD

    2015-01-01

    © 2015 Society for the Study of Amphibians and Reptiles. Western Pond Turtles (Actinemys marmorata) are endemic to western North America and are found in a diversity of aquatic habitats. To date, few studies have examined the ecology of populations in ephemeral or intermittent ponds. Here, we studied the terrestrial habitat requirements of Western Pond Turtles in an intermittent pond that dries in years with below-average rainfall. We tracked terrestrial movements of Western Pond Turtles in a...

  12. An aquatic ecosystem in space.

    Science.gov (United States)

    Voeste, D; Andriske, M; Paris, F; Levine, H G; Blum, V

    1999-07-01

    The Closed Equilibrated Biological Aquatic System (CEBAS) Mini-Module experiment was designed to study aquatic ecosystem performance within a middeck locker on the Space Shuttle. CEBAS was flown aboard STS-89 in January 1998 with a population of four pregnant Xiphophorus helleri female fish and eleven adult Biomphalaria glabrata snails in the first compartment and 200 juvenile X. helleri and 48 adult and juvenile B. glabrata in the second compartment. A plant compartment contained eleven snails and 53 g of the aquatic angiosperm Ceratophyllum demersum. During the flight, Ceratophyllum fresh weight increased from 53 g to 117 g. All adult fish and 65 juveniles survived the flight experiment and 37 adult snails and 40 newly laid snail spawn packs were recovered after the flight. Oxygen production and pH were as expected.

  13. Benthic habitat mapping using hyperspectral remote sensing

    Science.gov (United States)

    Vélez-Reyes, Miguel; Goodman, James A.; Castrodad-Carrau, Alexey; Jiménez-Rodriguez, Luis O.; Hunt, Shawn D.; Armstrong, Roy

    2006-09-01

    Benthic habitats are the different bottom environments as defined by distinct physical, geochemical, and biological characteristics. Remote sensing is increasingly being used to map and monitor the complex dynamics associated with estuarine and nearshore benthic habitats. Advantages of remote sensing technology include both the qualitative benefits derived from a visual overview, and more importantly, the quantitative abilities for systematic assessment and monitoring. Advancements in instrument capabilities and analysis methods are continuing to expand the accuracy and level of effectiveness of the resulting data products. Hyperspectral sensors in particular are rapidly emerging as a more complete solution, especially for the analysis of subsurface shallow aquatic systems. The spectral detail offered by hyperspectral instruments facilitates significant improvements in the capacity to differentiate and classify benthic habitats. This paper reviews two techniques for mapping shallow coastal ecosystems that both combine the retrieval of water optical properties with a linear unmixing model to obtain classifications of the seafloor. Example output using AVIRIS hyperspectral imagery of Kaneohe Bay, Hawaii is employed to demonstrate the application potential of the two approaches and compare their respective results.

  14. Aquatic Natural Areas Analysis and Evaluation: Oak Ridge Reservation

    Energy Technology Data Exchange (ETDEWEB)

    Baranski, Dr. Michael J. [Catawba College

    2011-04-01

    This report presents an assessment of the natural area value of eight Aquatic Natural Areas (ANAs) and seven Aquatic Reference Areas (ARAs) on the Oak Ridge Reservation (ORR) in Anderson and Roane Counties in east Tennessee. It follows a previous study in 2009 that analyzed and evaluated terrestrial natural areas on the Reservation. The purpose of both studies was to evaluate and rank those specially designated areas on the Reservation that contain sensitive species, special habitats, and natural area value. Natural areas receive special protections through established statutes, regulations, and policies. The ORR contains 33,542 acres (13,574 ha) administered by the Department of Energy. The surface waters of the Reservation range from 1st-order to 5th-order streams, but the majority of the streams recognized as ANAs and ARAs are 1st- and 2nd-order streams. East Fork Poplar Creek is a 4th-order stream and the largest watershed that drains Reservation lands. All the waters of the Reservation eventually reach the Clinch River on the southern and western boundaries of the ORR. All available information was collected, synthesized, and evaluated. Field observations were made to support and supplement the available information. Geographic information system mapping techniques were used to develop several quantitative attributes about the study areas. Narrative descriptions of each ANA and ARA and tables of numerical data were prepared. Criteria for assessment and evaluation were developed, and eight categories of factors were devised to produce a ranking system. The evaluation factors used in the ranking system were: (A) size of area, (B) percentage of watershed protected, (C) taxa present with protected status, (D) overall biotic diversity, (E) stream features, (F) water quality and use support ratings, (G) disturbance regime, and (H) other factors. Each factor was evaluated on a 5-point ranking scale (0-4), and each area received a composite score, where 32 was the

  15. Hydrologic and water-quality rehabilitation of environments for suitable fish habitat

    Science.gov (United States)

    Zhao, C. S.; Yang, S. T.; Xiang, H.; Liu, C. M.; Zhang, H. T.; Yang, Z. L.; Zhang, Y.; Sun, Y.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.

    2015-11-01

    Aquatic ecological rehabilitation is attracting increasing public and research attention, but without knowledge of the responses of aquatic species to their habitats the success of habitat restoration is uncertain. Thus efficient study of species response to habitat, through which to prioritize the habitat factors influencing aquatic ecosystems, is highly important. However many current models have too high requirement for assemblage information and have great bias in results due to consideration of only the species' attribute of presence/absence, abundance or biomass, thus hindering the wider utility of these models. This paper, using fish as a case, presents a framework for identification of high-priority habitat factors based on the responses of aquatic species to their habitats, using presence/absence, abundance and biomass data. This framework consists of four newly developed sub-models aiming to determine weightings for the evaluation of species' contributions to their communities, to quantitatively calculate an integrated habitat suitability index for multi-species based on habitat factors, to assess the suitable probability of habitat factors and to assess the rehabilitation priority of habitat factors. The framework closely links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. Breakpoint identification techniques based on curvature in cumulated dominance along with a newly developed weighting calculation model based on theory of mass systems were used to help identify the dominant fish, based on which the presence and abundance of multiple fish were normalized to estimate the integrated habitat suitability index along gradients of various factors, based on their variation with principal habitat factors. Then, the appropriate probability of every principal habitat factor was

  16. Invaded habitats. Chapter 4

    Directory of Open Access Journals (Sweden)

    Carlos Lopez-Vaamonde

    2010-07-01

    Full Text Available More than 65% (1040 species of arthropod species alien to Europe are associated with human-made habitats, especially parks and gardens, human settlements and agricultural lands, whereas woodlands are yet colonized by less than 20% of the alien fauna, which still has a negligible representation in the other natural and semi-natural habitats. Large differences in habitat affinity are observed between alien taxonomic groups. Phytophagous species are predominant among aliens, representing 47.2% of species alien to Europe.

  17. Aquatic polymers can drive pathogen transmission in coastal ecosystems.

    Science.gov (United States)

    Shapiro, Karen; Krusor, Colin; Mazzillo, Fernanda F M; Conrad, Patricia A; Largier, John L; Mazet, Jonna A K; Silver, Mary W

    2014-11-22

    Gelatinous polymers including extracellular polymeric substances (EPSs) are fundamental to biophysical processes in aquatic habitats, including mediating aggregation processes and functioning as the matrix of biofilms. Yet insight into the impact of these sticky molecules on the environmental transmission of pathogens in the ocean is limited. We used the zoonotic parasite Toxoplasma gondii as a model to evaluate polymer-mediated mechanisms that promote transmission of terrestrially derived pathogens to marine fauna and humans. We show that transparent exopolymer particles, a particulate form of EPS, enhance T. gondii association with marine aggregates, material consumed by organisms otherwise unable to access micrometre-sized particles. Adhesion to EPS biofilms on macroalgae also captures T. gondii from the water, enabling uptake of pathogens by invertebrates that feed on kelp surfaces. We demonstrate the acquisition, concentration and retention of T. gondii by kelp-grazing snails, which can transmit T. gondii to threatened California sea otters. Results highlight novel mechanisms whereby aquatic polymers facilitate incorporation of pathogens into food webs via association with particle aggregates and biofilms. Identifying the critical role of invisible polymers in transmission of pathogens in the ocean represents a fundamental advance in understanding and mitigating the health impacts of coastal habitat pollution with contaminated runoff.

  18. Smalltooth Sawfish Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for smalltooth sawfish (Pristis pectinatat) as designated by 74 FR 45353, September 2, 2009, Rules and Regulations.

  19. Johnsons Seagrass Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Johnson's Seagrass as designated by Federal Register Vol. 65, No. 66, Wednesday, April 5, 2000, Rules and Regulations.

  20. Right Whale Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Right Whale as designated by Federal Register Vol. 59, No. 28805, May 19, 1993, Rules and Regulations.

  1. Habitat Mapping Camera (HABCAM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset entails imagery collected using the HabCam towed underwater vehicle and annotated data on objects or habitats in the images and notes on image...

  2. Critical Habitat Designations

    Data.gov (United States)

    Department of Homeland Security — The Endangered Species Act (ESA) requires the Federal government to designate 'critical habitat' for any species it lists under the ESA. This dataset combines both...

  3. Designated Critical Habitat

    Data.gov (United States)

    Kansas Data Access and Support Center — Critical habitats include those areas documented as currently supporting self-sustaining populations of any threatened or endangered species of wildlife as well as...

  4. Green Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  5. Green Turtle Critical Habitat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  6. Energetic extremes in aquatic locomotion by coral reef fishes.

    Directory of Open Access Journals (Sweden)

    Christopher J Fulton

    Full Text Available Underwater locomotion is challenging due to the high friction and resistance imposed on a body moving through water and energy lost in the wake during undulatory propulsion. While aquatic organisms have evolved streamlined shapes to overcome such resistance, underwater locomotion has long been considered a costly exercise. Recent evidence for a range of swimming vertebrates, however, has suggested that flapping paired appendages around a rigid body may be an extremely efficient means of aquatic locomotion. Using intermittent flow-through respirometry, we found exceptional energetic performance in the Bluelined wrasse Stethojulis bandanensis, which maintains tuna-like optimum cruising speeds (up to 1 metre s(-1 while using 40% less energy than expected for their body size. Displaying an exceptional aerobic scope (22-fold above resting, streamlined rigid-body posture, and wing-like fins that generate lift-based thrust, S. bandanensis literally flies underwater to efficiently maintain high optimum swimming speeds. Extreme energetic performance may be key to the colonization of highly variable environments, such as the wave-swept habitats where S. bandanensis and other wing-finned species tend to occur. Challenging preconceived notions of how best to power aquatic locomotion, biomimicry of such lift-based fin movements could yield dramatic reductions in the power needed to propel underwater vehicles at high speed.

  7. Habitats, activities, and signs

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh; Brynskov, Martin

    2004-01-01

    Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational......, and pragmatic, 2) proposes a notation, and 3) sketches a method and exemplifies areas of application using authentic cases from hospital work, primary school education, the maritime domain, and other areas...

  8. Morbillivirus infections in aquatic mammals

    NARCIS (Netherlands)

    I.K.G. Visser (Ilona); M.F. van Bressem; T. Barrett (Thomas); A.D.M.E. Osterhaus (Ab)

    1993-01-01

    textabstractInfections with morbilliviruses have caused heavy losses among different populations of aquatic mammals during the last 5 years. Two different morbilliviruses were isolated from disease outbreaks among seals in Europe and Siberia: phocid distemper virus-1 (PDV-1) and phocid distemper vir

  9. Macrophytes: Ecology of aquatic plants

    NARCIS (Netherlands)

    Bornette, G.; Puijalon, S.

    2009-01-01

    Aquatic plants contribute to maintaining key functions and related biodiversity in freshwater ecosystems, and to provide the needs of human societies. The way the ecological niches of macrophytes are determined by abiotic filters and biotic ones is considered. A simple, broadly applicable model of t

  10. Fire and aquatic ecosystems in forested biomes of North America

    Science.gov (United States)

    Gresswell, Robert E.

    1999-01-01

    Synthesis of the literature suggests that physical, chemical, and biological elements of a watershed interact with long-term climate to influence fire regime, and that these factors, in concordance with the postfire vegetation mosaic, combine with local-scale weather to govern the trajectory and magnitude of change following a fire event. Perturbation associated with hydrological processes is probably the primary factor influencing postfire persistence of fishes, benthic macroinvertebrates, and diatoms in fluvial systems. It is apparent that salmonids have evolved strategies to survive perturbations occurring at the frequency of wildland fires (100a??102 years), but local populations of a species may be more ephemeral. Habitat alteration probably has the greatest impact on individual organisms and local populations that are the least mobile, and reinvasion will be most rapid by aquatic organisms with high mobility. It is becoming increasingly apparent that during the past century fire suppression has altered fire regimes in some vegetation types, and consequently, the probability of large stand-replacing fires has increased in those areas. Current evidence suggests, however, that even in the case of extensive high-severity fires, local extirpation of fishes is patchy, and recolonization is rapid. Lasting detrimental effects on fish populations have been limited to areas where native populations have declined and become increasingly isolated because of anthropogenic activities. A strategy of protecting robust aquatic communities and restoring aquatic habitat structure and life history complexity in degraded areas may be the most effective means for insuring the persistence of native biota where the probability of large-scale fires has increased.

  11. Aquatic Macrophyte Risk Assessment for Pesticides

    NARCIS (Netherlands)

    Maltby, L.; Arnold, D.; Arts, G.H.P.; Davies, J.; Heimbach, F.; Pickl, C.; Poulsen, V.

    2009-01-01

    Given the essential role that primary producers play in aquatic ecosystems, it is imperative that the potential risk of pesticides to the structure and functioning of aquatic plants is adequately assessed. This book discusses the assessment of the risk of pesticides with herbicidal activity to aquat

  12. Biodiversity value of agricultural drainage ditches; a comparative analysis of the aquatic invertebrate fauna of ditches and small lakes.

    NARCIS (Netherlands)

    Verdonschot, R.C.M.; Keizer-Vlek, H.E.; Verdonschot, P.F.M.

    2011-01-01

    1. Drainage ditches are a common aquatic habitat in the lowland agricultural landscape of north-western Europe. The invertebrate fauna of these waters is poorly known compared with that of the semi-natural wetland fragments found in this region. While most wetlands are designated as nature reserves,

  13. Dam removal, connectivity, and aquatic resources in the St. Regis River Watershed, New York

    Science.gov (United States)

    McKenna Jr, James E.; Hanak, Kaitlin; DeVilbiss, Katharine; David, Anthony; Johnson, James H.

    2015-10-09

    The decommissioning and planned removal of the Hogansburg Dam on the St. Regis River in New York has stimulated interest in the potential effects of that barrier removal on the St. Regis watershed. There will be immediate and systemic effects of the Hogansburg Dam removal, which may include inundation of habitats below the dam or dewatering of habitats above the dam, possibly affecting local fish assemblages and (or) local native mussel assemblages; and expansion of stream network connectivity, which has the potential to open a large area of the watershed to migratory aquatic species. Information was collected about biota, water quality, sediment distribution, riverbed dimensions in the vicinity of the dam, and habitat characteristics of headwater sample sites. Complete fish assemblages were collected, but species of special concern associated with the connectivity changes included, American Eel, Atlantic Salmon, Brook Trout, Eastern Sand Darter, and Lake Sturgeon. Freshwater mussels in the vicinity of the dam also were examined and may be at risk of exposure (without a rescue plan) after dam removal. Reservoir sediment will be transported downstream and will alter aquatic habitat as it moves through the system. The dam removal will open more than 440 kilometers of stream habitat to migratory species, allowing them to more easily complete their life cycles. Fish assemblages above the dam may be altered by migrating fishes, but resident Brook Trout are not expected to be adversely affected.

  14. Act together – implications of symbioses in aquatic ciliates

    Directory of Open Access Journals (Sweden)

    Claudia eDziallas

    2012-08-01

    Full Text Available Mutual interactions in form of symbioses can increase the fitness of organisms and provide them with the capacity to occupy new ecological niches. The formation of obligate symbioses allows for rapid evolution of new life forms including multitrophic consortia. Microbes are important components of many known endosymbioses and their short generation times and strong potential for genetic exchange may be important drivers of speciation. Hosts provide endo- and ectosymbionts with stable, nutrient-rich environments and protection from environmental stresses. This is of particular importance in aquatic ecosystems, which are often highly variable, harsh and nutrient-deficient habitats. Thus it is not surprising that symbioses are widespread in both marine and freshwater environments. Symbioses in aquatic ciliates are good model systems for exploring symbiont-host interactions. Many ciliate species are globally distributed and have been intensively studied in the context of plastid evolution. Their relatively large cell size offers an ideal habitat for numerous microorganisms with different functional traits including commensalism and parasitism. Phagocytosis facilitates the formation of symbiotic relationships, particularly since some ingested microorganisms can escape the digestion. For example, photoautotrophic algae and methanogens represent endosymbionts that greatly extend the biogeochemical functions of their hosts. Consequently, symbiotic relationships between protists and prokaryotes are widespread and often result in new ecological functions of symbiotic communities. This enables ciliates to thrive under a wide range of environmental conditions including ultraoligotrophic or anoxic habitats. We summarize the current understanding of this exciting research topic to identify the many areas in which knowledge is lacking and to stimulate future research by providing an overview on new methodologies and by formulating a number of emerging

  15. CUMULATIVE EFFECTS OF COASTAL HABITAT ALTERATIONS ON FISHERY RESOURCES: TOWARD PREDICTION AT REGIONAL SCALES

    Science.gov (United States)

    The integrity of aquatic ecosystems and habitats at the land-sea interface is challeneged by several forces, ranging from plot scale destruction and disturbance, to watershed scale perturbations, to global changes in climate and human demographis. The scientific challenge is to ...

  16. Ecosystem Services of Coastal Habitats and Fisheries: Multi-Scale Ecological and Economic Modeling

    Science.gov (United States)

    Critical habitats for fish and wildlife often are small patches in landscapes, e.g., aquatic vegetation beds, reefs, isolated ponds and wetlands, remnant old growth forests, etc, yet the same animal populations that depend on these patches for reproduction or survival can be exte...

  17. 75 FR 19994 - Green Diamond Resource Company, California Timberlands Division, Forest Management Habitat...

    Science.gov (United States)

    2010-04-16

    ... where it actually kills or injures wildlife by significantly impairing essential behavioral patterns... to Green Diamond, based on a federally approved Aquatic HCP designed to address listed and unlisted... habitat associated with all or some portion of active spotted owl sites well distributed throughout...

  18. Lichens of neglected habitats in Eastern and East-Central European lowlands

    Directory of Open Access Journals (Sweden)

    Jurga Motiejūnaitē

    2013-12-01

    Full Text Available Situation of lichens of aquatic and transient habitats in Eastern and East-Central European lowlands is discussed basing on example of several selected species: Leptogium biatorinum, Sarcosagium campestre, Steinia geophana, Verrucaria aquatilis, V. hydrela, V. praetermissa, V. xyloxena. Both habitat types are generally very much neglected in the region and all species show large spatial gaps in recording, which makes it difficult to judge both about their true distribution limits and spreading dynamics. On the other hand, targeted search through the suitable habitats and abundance of such indicate that many of these lichens are probably not uncommon in the region.

  19. Energetic consequences of a major change in habitat use: endangered Brent Geese Branta bernicla hrota losing their main food source

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Clausen, Preben; Fælled, Casper Cæsar;

    2012-01-01

    Coastal seagrasses are declining at increasing rates worldwide, forcing herbivores previously reliant on these habitats to abandon them in search of alternative ways to fulfil their daily energy budgets. After two decades of declining seagrass abundance in Mariager Fjord, Denmark, the Svalbard...... habitats such as saltmarsh and winter wheat. In contrast to those birds exploiting aquatic habitats, birds relying on these new habitats showed higher energy expenditure and failed to balance their energy budget. Eelgrass (Zostera) was energetically superior to other food resources, with marine Ulva being...

  20. Assessment of potential aquatic herbicide impacts to California aquatic ecosystems.

    Science.gov (United States)

    Siemering, Geoffrey S; Hayworth, Jennifer D; Greenfield, Ben K

    2008-10-01

    A series of legal decisions culminated in 2002 with the California State Water Resources Control Board funding the San Francisco Estuary Institute to develop and implement a 3-year monitoring program to determine the potential environmental impacts of aquatic herbicide applications. The monitoring program was intended to investigate the behavior of all aquatic pesticides in use in California, to determine potential impacts in a wide range of water-body types receiving applications, and to help regulators determine where to direct future resources. A tiered monitoring approach was developed to achieve a balance between program goals and what was practically achievable within the project time and budget constraints. Water, sediment, and biota were collected under "worst-case" scenarios in close association with herbicide applications. Applications of acrolein, copper sulfate, chelated copper, diquat dibromide, glyphosate, fluridone, triclopyr, and 2,4-D were monitored. A range of chemical analyses, toxicity tests, and bioassessments were conducted. At each site, risk quotients were calculated to determine potential impacts. For sediment-partitioning herbicides, sediment quality triad analysis was performed. Worst-case scenario monitoring and special studies showed limited short-term and no long-term toxicity directly attributable to aquatic herbicide applications. Risk quotient calculations called for additional risk characterizations; these included limited assessments for glyphosate and fluridone and more extensive risk assessments for diquat dibromide, chelated copper products, and copper sulfate. Use of surfactants in conjunction with aquatic herbicides was positively associated with greater ecosystem impacts. Results therefore warrant full risk characterization for all adjuvant compounds. PMID:18293029

  1. Carbonic anhydrase levels and internal lacunar CO/sub 2/ concentrations in aquatic macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.I.

    1979-01-01

    Carbonic anhydrase levels were examined in a variety of aquatic macrophytes from different habitats. In general, carbonic anhydrase levels increased across the habitat gradient such that activities were low in submersed aquatic macrophytes and high in emergent macrophytes with floating-leaved and free-floating plants exhibiting intermediate activities. Internal lacunar CO/sub 2/ concentrations were analyzed in relation to carbonic anhydrase activities. There was no correlation between these two parameters. Internal CO/sub 2/ concentrations ranged from low to high in submersed macrophytes, but were low in floating-leaved and emergent macrophytes. The observed internal CO/sub 2/ concentrations are discussed in relation to the individual morphologies of the plants and the environments in which they occurred.

  2. Proposed Release Guides to Protect Aquatic Biota

    Energy Technology Data Exchange (ETDEWEB)

    Marter, W.L.

    2001-03-28

    At the request of South Carolina Department of Health and Environmental Control (SCDHEC) and the Department of Energy (DOE), the Savannah River Laboratory was assigned the task of developing the release guides to protect aquatic biota. A review of aquatic radioecology literature by two leading experts in the field of radioecology concludes that exposure of aquatic biota at one rad per day or less will not produce detectable deleterious effects on aquatic organisms. On the basis of this report, DOE recommends the use of one rad per day as an interim dose standard to protect aquatic biota.

  3. Freshwater Ecosystems and Resilience of Pacific Salmon: Habitat Management Based on Natural Variability

    Directory of Open Access Journals (Sweden)

    Gordon H. Reeves

    2009-06-01

    Full Text Available In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologically unsustainable conditions may partly explain this lack of response. Natural watershed processes generate highly variable environmental conditions and population responses, i.e., multiple life histories, that are often not considered in restoration. Examples from several locations underscore the importance of natural variability to the resilience of Pacific salmon. The implication is that habitat restoration efforts will be more likely to foster salmon resilience if they consider processes that generate and maintain natural variability in fresh water. We identify three specific criteria for management based on natural variability: the capacity of aquatic habitat to recover from disturbance, a range of habitats distributed across stream networks through time sufficient to fulfill the requirements of diverse salmon life histories, and ecological connectivity. In light of these considerations, we discuss current threats to habitat resilience and describe how regulatory and restoration approaches can be modified to better incorporate natural variability.

  4. Freshwater ecosystems and resilience of Pacific salmon: Habitat Management based on natural variability

    Science.gov (United States)

    Bisson, P.A.; Dunham, J.B.; Reeves, G.H.

    2009-01-01

    In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologically unsustainable conditions may partly explain this lack of response. Natural watershed processes generate highly variable environmental conditions and population responses, i.e., multiple life histories, that are often not considered in restoration. Examples from several locations underscore the importance of natural variability to the resilience of Pacific salmon. The implication is that habitat restoration efforts will be more likely to foster salmon resilience if they consider processes that generate and maintain natural variability in fresh water. We identify three specific criteria for management based on natural variability: the capacity of aquatic habitat to recover from disturbance, a range of habitats distributed across stream networks through time sufficient to fulfill the requirements of diverse salmon life histories, and ecological connectivity. In light of these considerations, we discuss current threats to habitat resilience and describe how regulatory and restoration approaches can be modified to better incorporate natural variability. ?? 2009 by the author(s).

  5. Azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.

    Directory of Open Access Journals (Sweden)

    Florence Wisniewski-Dyé

    2011-12-01

    Full Text Available Fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (Gyr and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyzed their gene origins. While most Azospirillum house-keeping genes have orthologs in its close aquatic relatives, this lineage has obtained nearly half of its genome from terrestrial organisms. The majority of genes encoding functions critical for association with plants are among horizontally transferred genes. Our results show that transition of some aquatic bacteria to terrestrial habitats occurred much later than the suggested initial divergence of hydro- and terrabacterial clades. The birth of the genus Azospirillum approximately coincided with the emergence of vascular plants on land.

  6. Gradual adaptation of bone structure to aquatic lifestyle in extinct sloths from Peru.

    Science.gov (United States)

    Amson, Eli; de Muizon, Christian; Laurin, Michel; Argot, Christine; de Buffrénil, Vivian

    2014-05-01

    Non-pathological densification (osteosclerosis) and swelling (pachyostosis) of bones are the main modifications affecting the skeleton of land vertebrates (tetrapods) that returned to water. However, a precise temporal calibration of the acquisition of such adaptations is still wanting. Here, we assess the timing of such acquisition using the aquatic sloth Thalassocnus, from the Neogene of the Pisco Formation, Peru. This genus is represented by five species occurring in successive vertebrate-bearing horizons of distinct ages. It yields the most detailed data about the gradual acquisition of aquatic adaptations among tetrapods, in displaying increasing osteosclerosis and pachyostosis through time. Such modifications, reflecting a shift in the habitat from terrestrial to aquatic, occurred over a short geological time span (ca 4 Myr). Otherwise, the bones of terrestrial pilosans (sloths and anteaters) are much more compact than the mean mammalian condition, which suggests that the osteosclerosis of Thalassocnus may represent an exaptation.

  7. Phenotypic flexibility of gape anatomy fine-tunes the aquatic prey-capture system of newts

    Science.gov (United States)

    van Wassenbergh, Sam; Heiss, Egon

    2016-07-01

    A unique example of phenotypic flexibility of the oral apparatus is present in newts (Salamandridae) that seasonally change between an aquatic and a terrestrial habitat. Newts grow flaps of skin between their upper and lower jaws, the labial lobes, to partly close the corners of the mouth when they adopt an aquatic lifestyle during their breeding season. Using hydrodynamic simulations based on μCT-scans and cranial kinematics during prey-capture in the smooth newt (Lissotriton vulgaris), we showed that this phenotypic flexibility is an adaptive solution to improve aquatic feeding performance: both suction distance and suction force increase by approximately 15% due to the labial lobes. As the subsequent freeing of the corners of the mouth by resorption of the labial lobes is assumed beneficial for the terrestrial capture of prey by the tongue, this flexibility of the mouth fine-tunes the process of capturing prey throughout the seasonal switching between water and land.

  8. ISOLATION OF FILAMENTOUS FUNGI ASSOCIATED WITH TWO COMMON EDIBLE AQUATIC INSECTS, HYDROPHILUS PICEUS AND DYTISCUS MARGINALIS

    OpenAIRE

    Ozlem Gur; Ahmet Polat; Umit Incekara; Murat Ozdal; Esabi Basaran Kurbanoglu,Gani Erhan Tasar

    2012-01-01

    Insects are widely used for their potential source of protein, lipids, carbohydrates and certain vitamins in many parts of the world. As in terrestial ones, aquatic insects can also carry fungal structures. Therefore, in the present study, we evaluated microfungal flora of internal and external surface of Hydrophilus piceus and Dytiscus marginalis collected from their natural habitats in Erzurum (Turkey). We isolated total 19 different species of fungi belonging to Penicillium, Alternaria, Be...

  9. Herbivory and growth in terrestrial and aquatic populations of amphibious stream plants

    DEFF Research Database (Denmark)

    Sand-Jensen, Kaj; Jacobsen, Dean

    2002-01-01

    1. Many amphibious plant species grow in the transition between terrestrial and submerged vegetation in small lowland streams. We determined biomass development, leaf turnover rate and invertebrate herbivory during summer in terrestrial and aquatic populations of three amphibious species to evalu...... that the ability of amphibious plants to grow submerged permits them to expand their niche and escape intense competition on land, but the stream does not provide a refugium against grazing and constrains plant production compared with the terrestrial habitat....

  10. Ecological opportunities, habitat, and past climatic fluctuations influenced the diversification of modern turtles.

    Science.gov (United States)

    Rodrigues, João Fabrício Mota; Diniz-Filho, José Alexandre Felizola

    2016-08-01

    Habitat may be viewed as an important life history component potentially related to diversification patterns. However, differences in diversification rates between aquatic and terrestrial realms are still poorly explored. Testudines is a group distributed worldwide that lives in aquatic and terrestrial environments, but until now no-one has evaluated the diversification history of the group as a whole. We aim here to investigate the diversification history of turtles and to test if habitat influenced speciation rate in these animals. We reconstructed the phylogeny of the modern species of chelonians and estimated node divergence dates using molecular markers and a Bayesian approach. Then, we used Bayesian Analyses of Macroevolutionary Mixtures to evaluate the diversification history of turtles and evaluate the effect of habitat on this pattern. Our reconstructed phylogeny covered 300 species (87% of the total diversity of the group). We found that the emydid subfamily Deirochelyinae, which forms the turtle hotspot in south-eastern United States, had an increase in its speciation rate, and that Galapagos tortoises had similar increases. Current speciation rates are lower in terrestrial turtles, contradicting studies supporting the idea terrestrial animals diversify more than aquatic species. Our results suggest that habitat, ecological opportunities, island invasions, and climatic factors are important drivers of diversification in modern turtles and reinforce the importance of habitat as a diversification driver. PMID:27233435

  11. Effect of leaf type and pesticide exposure on abundance of bacterial taxa in mosquito larval habitats.

    Directory of Open Access Journals (Sweden)

    Ephantus J Muturi

    Full Text Available Lentic freshwater systems including those inhabited by aquatic stages of mosquitoes derive most of their carbon inputs from terrestrial organic matter mainly leaf litter. The leaf litter is colonized by microbial communities that provide the resource base for mosquito larvae. While the microbial biomass associated with different leaf species in container aquatic habitats is well documented, the taxonomic composition of these microbes and their response to common environmental stressors is poorly understood. We used indoor aquatic microcosms to determine the abundances of major taxonomic groups of bacteria in leaf litters from seven plant species and their responses to low concentrations of four pesticides with different modes of action on the target organisms; permethrin, malathion, atrazine and glyphosate. We tested the hypotheses that leaf species support different quantities of major taxonomic groups of bacteria and that exposure to pesticides at environmentally relevant concentrations alters bacterial abundance and community structure in mosquito larval habitats. We found support for both hypotheses suggesting that leaf litter identity and chemical contamination may alter the quality and quantity of mosquito food base (microbial communities in larval habitats. The effect of pesticides on microbial communities varied significantly among leaf types, suggesting that the impact of pesticides on natural microbial communities may be highly complex and difficult to predict. Collectively, these findings demonstrate the potential for detritus composition within mosquito larval habitats and exposure to pesticides to influence the quality of mosquito larval habitats.

  12. Model-Based Selection of Areas for the Restoration of Acrocephalus paludicola Habitats in NE Germany

    Science.gov (United States)

    Frick, Annett; Tanneberger, Franziska; Bellebaum, Jochen

    2014-04-01

    The global Aquatic Warbler ( Acrocephalus paludicola, Vieillot, 1817) population has suffered a major decline due to the large-scale destruction of its natural habitat (fen mires). The species is at risk of extinction, especially in NE Germany/NW Poland. In this study, we developed habitat suitability models based on satellite and environmental data to identify potential areas for habitat restoration on which further surveys and planning should be focused. To create a reliable model, we used all Aquatic Warbler presences in the study area since 1990 as well as additional potentially suitable habitats identified in the field. We combined the presence/absence regression tree algorithm Cubist with the presence-only algorithm Maxent since both commonly outperform other algorithms. To integrate the separate model results, we present a new way to create a metamodel using the initial model results as variables. Additionally, a histogram approach was applied to further reduce the final search area to the most promising sites. Accuracy increased when using both remote sensing and environmental data. It was highest for the integrated metamodel (Cohen's Kappa of 0.4, P < 0.001). The final result of this study supports the selection of the most promising sites for Aquatic Warbler habitat restoration.

  13. Ecological opportunities, habitat, and past climatic fluctuations influenced the diversification of modern turtles.

    Science.gov (United States)

    Rodrigues, João Fabrício Mota; Diniz-Filho, José Alexandre Felizola

    2016-08-01

    Habitat may be viewed as an important life history component potentially related to diversification patterns. However, differences in diversification rates between aquatic and terrestrial realms are still poorly explored. Testudines is a group distributed worldwide that lives in aquatic and terrestrial environments, but until now no-one has evaluated the diversification history of the group as a whole. We aim here to investigate the diversification history of turtles and to test if habitat influenced speciation rate in these animals. We reconstructed the phylogeny of the modern species of chelonians and estimated node divergence dates using molecular markers and a Bayesian approach. Then, we used Bayesian Analyses of Macroevolutionary Mixtures to evaluate the diversification history of turtles and evaluate the effect of habitat on this pattern. Our reconstructed phylogeny covered 300 species (87% of the total diversity of the group). We found that the emydid subfamily Deirochelyinae, which forms the turtle hotspot in south-eastern United States, had an increase in its speciation rate, and that Galapagos tortoises had similar increases. Current speciation rates are lower in terrestrial turtles, contradicting studies supporting the idea terrestrial animals diversify more than aquatic species. Our results suggest that habitat, ecological opportunities, island invasions, and climatic factors are important drivers of diversification in modern turtles and reinforce the importance of habitat as a diversification driver.

  14. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate. PMID:26841246

  15. Distribution and frequency of kdr mutations within Anopheles gambiae s.l. populations and first report of the ace.1 G119S mutation in Anopheles arabiensis from Burkina Faso (West Africa.

    Directory of Open Access Journals (Sweden)

    Roch K Dabiré

    Full Text Available An entomological survey was carried out at 15 sites dispersed throughout the three eco-climatic regions of Burkina Faso (West Africa in order to assess the current distribution and frequency of mutations that confer resistance to insecticides in An. gambiae s.l. populations in the country. Both knockdown (kdr resistance mutation variants (L1014F and L1014S, that confer resistance to pyrethroid insecticides, were identified concomitant with the ace-1 G119S mutation confirming the presence of multiple resistance mechanisms in the An. gambiae complex in Burkina Faso. Compared to the last survey, the frequency of the L1014F kdr mutation appears to have remained largely stable and relatively high in all species. In contrast, the distribution and frequency of the L1014S mutation has increased significantly in An. gambiae s.l. across much of the country. Furthermore we report, for the first time, the identification of the ace.1 G119S mutation in An. arabiensis populations collected at 8 sites [corrected]. This mutation, which confers resistance to organophosphate and carbamate insecticides, has been reported previously only in the An. gambiae S and M molecular forms. This finding is significant as organophosphates and carbamates are used in indoor residual sprays (IRS to control malaria vectors as complementary strategies to the use of pyrethroid impregnated bednets. The occurrence of the three target-site resistance mutations in both An. gambiae molecular forms and now An. arabiensis has significant implications for the control of malaria vector populations in Burkina Faso and for resistance management strategies based on the rotation of insecticides with different modes of action.

  16. Effects of Management Legacies on Stream Fish and Aquatic Benthic Macroinvertebrate Assemblages

    Science.gov (United States)

    Quist, Michael C.; Schultz, Randall D.

    2014-09-01

    Fish and benthic macroinvertebrate assemblages often provide insight on ecological conditions for guiding management actions. Unfortunately, land use and management legacies can constrain the structure of biotic communities such that they fail to reflect habitat quality. The purpose of this study was to describe patterns in fish and benthic macroinvertebrate assemblage structure, and evaluate relationships between biota and habitat characteristics in the Chariton River system of south-central Iowa, a system likely influenced by various potential management legacies (e.g., dams, chemical removal of fishes). We sampled fishes, benthic macroinvertebrates, and physical habitat from a total of 38 stream reaches in the Chariton River watershed during 2002-2005. Fish and benthic macroinvertebrate assemblages were dominated by generalist species tolerant of poor habitat quality; assemblages failed to show any apparent patterns with regard to stream size or longitudinal location within the watershed. Metrics used to summarize fish assemblages and populations [e.g., presence-absence, relative abundance, Index of Biotic Integrity for fish (IBIF)] were not related to habitat characteristics, except that catch rates of piscivores were positively related to the depth and the amount of large wood. In contrast, family richness of benthic macroinvertebrates, richness of Ephemeroptera, Trichoptera, and Plecoptera taxa, and IBI values for benthic macroinvertebrates (IBIBM) were positively correlated with the amount of overhanging vegetation and inversely related to the percentage of fine substrate. A long history of habitat alteration by row-crop agriculture and management legacies associated with reservoir construction has likely resulted in a fish assemblage dominated by tolerant species. Intolerant and sensitive fish species have not recolonized streams due to downstream movement barriers (i.e., dams). In contrast, aquatic insect assemblages reflected aquatic habitat, particularly

  17. Aquatic and Terrestrial Environment 2004

    DEFF Research Database (Denmark)

    Andersen, J. M.; Boutrup, S.; Bijl, L. van der;

    , watercourses, lakes and marine waters and the pressures upon them and reviews the monitoring of terrestrial natural habitats and selected plants and animals. The report is based on the annual reports prepared for each subprogramme by the Topic Centres. The latter reports are mainly based on data collected...

  18. Evaluation of Macroinvertebrate Communities and Habitat for Selected Stream Reaches at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    L.J. Henne; K.J. Buckley

    2005-08-12

    This is the second aquatic biological monitoring report generated by Los Alamos National Laboratory's (LANL's) Water Quality and Hydrology Group. The study has been conducted to generate impact-based assessments of habitat and water quality for LANL waterways. The monitoring program was designed to allow for the detection of spatial and temporal trends in water and habitat quality through ongoing, biannual monitoring of habitat characteristics and benthic aquatic macroinvertebrate communities at six key sites in Los Alamos, Sandia, Water, Pajarito, and Starmer's Gulch Canyons. Data were collected on aquatic habitat characteristics, channel substrate, and macroinvertebrate communities during 2001 and 2002. Aquatic habitat scores were stable between 2001 and 2002 at all locations except Starmer's Gulch and Pajarito Canyon, which had lower scores in 2002 due to low flow conditions. Channel substrate changes were most evident at the upper Los Alamos and Pajarito study reaches. The macroinvertebrate Stream Condition Index (SCI) indicated moderate to severe impairment at upper Los Alamos Canyon, slight to moderate impairment at upper Sandia Canyon, and little or no impairment at lower Sandia Canyon, Starmer's Gulch, and Pajarito Canyon. Habitat, substrate, and macroinvertebrate data from the site in upper Los Alamos Canyon indicated severe impacts from the Cerro Grande Fire of 2000. Impairment in the macroinvertebrate community at upper Sandia Canyon was probably due to effluent-dominated flow at that site. The minimal impairment SCI scores for the lower Sandia site indicated that water quality improved with distance downstream from the outfall at upper Sandia Canyon.

  19. Earth is a Marine Habitat. Habitat Conservation Program.

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    This brochure is intended to educate the public about the need to conserve and preserve the earth's environment (man's habitat). It contains an introduction to the ocean world and threats to coastal habitat. Photos and narrative revolve around the theme "Earth is a Marine Habitat." Sections include: "The Web of Life,""Oceans and the United…

  20. Role of Marsh-Mangrove Interface Habitats as Aquatic Refuges for Wetland Fishes and Other Aquatic Animals

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — We examined spatial and temporal dynamics in the fish community of ecotonal mangrove creeks along the Shark River Slough transect, particularly between SRS3 &...

  1. Field evaluation of a two-dimensional hydrodynamic model near boulders for habitat calculation

    Science.gov (United States)

    Waddle, Terry

    2009-01-01

    Two-dimensional hydrodynamic models are now widely used in aquatic habitat studies. To test the sensitivity of calculated habitat outcomes to limitations of such a model and of typical field data, bathmetry, depth and velocity data were collected for three discharges in the vicinity of two large boulders in the South Platte River (Colorado) and used in the River2D model. Simulated depth and velocity were compared with observed values at 204 locations and the differences in habitat numbers produced by observed and simulated conditions were calculated. The bulk of the differences between simulated and observed depth and velocity values were found to lie within the likely error of measurement. However, the effect of flow simulation outliers on potential habitat outcomes must be considered when using 2D models for habitat simulation. Furthermore, the shape of the habitat suitability relation can influence the effects of simulation errors. Habitat relations with steep slopes in the velocity ranges found in similar study areas are expected to be sensitive to the magnitude of error found here. Comparison of habitat values derived from simulated and observed depth and velocity revealed a small tendency to under-predict habitat values.

  2. Field evaluation of a two-dimensinal hydrodynamic model near boulders for habitat calculation

    Science.gov (United States)

    Waddle, Terry

    2010-01-01

    Two-dimensional hydrodynamic models are now widely used in aquatic habitat studies. To test the sensitivity of calculated habitat outcomes to limitations of such a model and of typical field data, bathymetry, depth and velocity data were collected for three discharges in the vicinity of two large boulders in the South Platte River (Colorado) and used in the River2D model. Simulated depth and velocity were compared with observed values at 204 locations and the differences in habitat numbers produced by observed and simulated conditions were calculated. The bulk of the differences between simulated and observed depth and velocity values were found to lie within the likely error of measurement. However, the effect of flow simulation outliers on potential habitat outcomes must be considered when using 2D models for habitat simulation. Furthermore, the shape of the habitat suitability relation can influence the effects of simulation errors. Habitat relations with steep slopes in the velocity ranges found in similar study areas are expected to be sensitive to the magnitude of error found here. Comparison of habitat values derived from simulated and observed depth and velocity revealed a small tendency to under-predict habitat values.

  3. NEPR Benthic Habitat Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This benthic habitat map was created from a semi-automated habitat mapping process, using a combination of bathymetry, satellite imagery, aerial imagery and...

  4. From terrestrial to aquatic fluxes: Integrating stream dynamics within a dynamic global vegetation modeling framework

    Science.gov (United States)

    Hoy, Jerad; Poulter, Benjamin; Emmett, Kristen; Cross, Molly; Al-Chokhachy, Robert; Maneta, Marco

    2016-04-01

    Integrated terrestrial ecosystem models simulate the dynamics and feedbacks between climate, vegetation, disturbance, and hydrology and are used to better understand biogeography and biogeochemical cycles. Extending dynamic vegetation models to the aquatic interface requires coupling surface and sub-surface runoff to catchment routing schemes and has the potential to enhance how researchers and managers investigate how changes in the environment might impact the availability of water resources for human and natural systems. In an effort towards creating such a coupled model, we developed catchment-based hydrologic routing and stream temperature model to pair with LPJ-GUESS, a dynamic global vegetation model. LPJ-GUESS simulates detailed stand-level vegetation dynamics such as growth, carbon allocation, and mortality, as well as various physical and hydrologic processes such as canopy interception and through-fall, and can be applied at small spatial scales, i.e., 1 km. We demonstrate how the coupled model can be used to investigate the effects of transient vegetation dynamics and CO2 on seasonal and annual stream discharge and temperature regimes. As a direct management application, we extend the modeling framework to predict habitat suitability for fish habitat within the Greater Yellowstone Ecosystem, a 200,000 km2 region that provides critical habitat for a range of aquatic species. The model is used to evaluate, quantitatively, the effects of management practices aimed to enhance hydrologic resilience to climate change, and benefits for water storage and fish habitat in the coming century.

  5. CTUIR Umatilla Anadromous Fisheries Habitat Project : A Columbia River Basin Fish Habitat Project 2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hoverson, Eric D.; Amonette, Alexandra

    2009-02-09

    The Umatilla Anadromous Fisheries Habitat Project (UAFHP) is an ongoing effort to protect, enhance, and restore riparian and instream habitat for the natural production of anadromous salmonids in the Umatilla River Basin, Northeast Oregon. Flow quantity, water temperature, passage, and lack of in-stream channel complexity have been identified as the key limiting factors in the basin. During the 2008 Fiscal Year (FY) reporting period (February 1, 2008-January 31, 2009) primary project activities focused on improving instream and riparian habitat complexity, migrational passage, and restoring natural channel morphology and floodplain function. Eight primary fisheries habitat enhancement projects were implemented on Meacham Creek, Birch Creek, West Birch Creek, McKay Creek, West Fork Spring Hollow, and the Umatilla River. Specific restoration actions included: (1) rectifying one fish passage barrier on West Birch Creek; (2) participating in six projects planting 10,000 trees and seeding 3225 pounds of native grasses; (3) donating 1000 ft of fencing and 1208 fence posts and associated hardware for 3.6 miles of livestock exclusion fencing projects in riparian areas of West Birch and Meacham Creek, and for tree screens to protect against beaver damage on West Fork Spring Hollow Creek; (4) using biological control (insects) to reduce noxious weeds on three treatment areas covering five acres on Meacham Creek; (5) planning activities for a levee setback project on Meacham Creek. We participated in additional secondary projects as opportunities arose. Baseline and ongoing monitoring and evaluation activities were also completed on major project areas such as conducting photo point monitoring strategies activities at the Meacham Creek Large Wood Implementation Project site (FY2006) and at additional easements and planned project sites. Fish surveys and aquatic habitat inventories were conducted at project sites prior to implementation. Proper selection and implementation of

  6. Marine envenomations and aquatic dermatology.

    Science.gov (United States)

    Soppe, G G

    1989-08-01

    Jellyfish stings are usually mild except those caused by species in the South Pacific. The box jellyfish can produce a severe cardiorespiratory insult. The sting of the Portuguese man-of-war is more potent than that of the common jellyfish. The Indo-Pacific area is the source of the most venomous bony fish. Many injuries can be avoided by wearing shoes when walking in shallow water or tide pools. Aquatic-related skin infections may involve unusual organisms. Swimmer's itch, a disease of freshwater bathing, is caused by cercariae. Seabather's eruption produces a rash in swimsuit-covered areas; the etiology is not clear. PMID:2569260

  7. Predicting the resilience and recovery of aquatic systems: a framework for model evolution within environmental observatories

    Science.gov (United States)

    Hipsey, Matthew R.; Hamilton, David P.; Hanson, Paul C.; Carey, Cayelan C; Coletti, Janaine Z; Read, Jordan S.; Ibelings, Bas W; Valensini, Fiona J; Brookes, Justin D

    2015-01-01

    Maintaining the health of aquatic systems is an essential component of sustainable catchmentmanagement, however, degradation of water quality and aquatic habitat continues to challenge scientistsand policy-makers. To support management and restoration efforts aquatic system models are requiredthat are able to capture the often complex trajectories that these systems display in response to multiplestressors. This paper explores the abilities and limitations of current model approaches in meeting this chal-lenge, and outlines a strategy based on integration of flexible model libraries and data from observationnetworks, within a learning framework, as a means to improve the accuracy and scope of model predictions.The framework is comprised of a data assimilation component that utilizes diverse data streams from sensornetworks, and a second component whereby model structural evolution can occur once the model isassessed against theoretically relevant metrics of system function. Given the scale and transdisciplinarynature of the prediction challenge, network science initiatives are identified as a means to develop and inte-grate diverse model libraries and workflows, and to obtain consensus on diagnostic approaches to modelassessment that can guide model adaptation. We outline how such a framework can help us explore thetheory of how aquatic systems respond to change by bridging bottom-up and top-down lines of enquiry,and, in doing so, also advance the role of prediction in aquatic ecosystem management.

  8. Phytoremediation Potential of Aquatic Macrophyte, Azolla

    OpenAIRE

    Sood, Anjuli; Uniyal, Perm L.; Prasanna, Radha; Ahluwalia, Amrik S.

    2011-01-01

    Aquatic macrophytes play an important role in the structural and functional aspects of aquatic ecosystems by altering water movement regimes, providing shelter to fish and aquatic invertebrates, serving as a food source, and altering water quality by regulating oxygen balance, nutrient cycles, and accumulating heavy metals. The ability to hyperaccumulate heavy metals makes them interesting research candidates, especially for the treatment of industrial effluents and sewage waste water. The us...

  9. Understanding Aquatic Rhizosphere Processes Through Metabolomics and Metagenomics Approach

    Science.gov (United States)

    Lee, Yong Jian; Mynampati, Kalyan; Drautz, Daniela; Arumugam, Krithika; Williams, Rohan; Schuster, Stephan; Kjelleberg, Staffan; Swarup, Sanjay

    2013-04-01

    The aquatic rhizosphere is a region around the roots of aquatic plants. Many studies focusing on terrestrial rhizosphere have led to a good understanding of the interactions between the roots, its exudates and its associated rhizobacteria. The rhizosphere of free-floating roots, however, is a different habitat that poses several additional challenges, including rapid diffusion rates of signals and nutrient molecules, which are further influenced by the hydrodynamic forces. These can lead to rapid diffusion and complicates the studying of diffusible factors from both plant and/or rhizobacterial origins. These plant systems are being increasingly used for self purification of water bodies to provide sustainable solution. A better understanding of these processes will help in improving their performance for ecological engineering of freshwater systems. The same principles can also be used to improve the yield of hydroponic cultures. Novel toolsets and approaches are needed to investigate the processes occurring in the aquatic rhizosphere. We are interested in understanding the interaction between root exudates and the complex microbial communities that are associated with the roots, using a systems biology approach involving metabolomics and metagenomics. With this aim, we have developed a RhizoFlowCell (RFC) system that provides a controlled study of aquatic plants, observed the root biofilms, collect root exudates and subject the rhizosphere system to changes in various chemical or physical perturbations. As proof of concept, we have used RFC to test the response of root exudation patterns of Pandanus amaryllifolius after exposure to the pollutant naphthalene. Complexity of root exudates in the aquatic rhizosphere was captured using this device and analysed using LC-qTOF-MS. The highly complex metabolomic profile allowed us to study the dynamics of the response of roots to varying levels of naphthalene. The metabolic profile changed within 5mins after spiking with

  10. Physical Thresholds as Ecological Proxies in Aquatic Ecosystems

    Science.gov (United States)

    Hausner, M. B.; Gaines, D. B.; Morrison, R. R.; Sada, D. W.; Scoppettone, G. G.; Stone, M. C.; Suarez, F. I.; Tyler, S. W.; Wilson, K. P.

    2015-12-01

    It is often difficult to directly quantify ecological thresholds and predict ecological responses to changing environmental conditions. Here, we present two case studies from Death Valley National Park - Devils Hole and Travertine Springs - in which physical parameters are used as proxies for ecological processes to assess the consequences of environmental change on aquatic ecosystems. In Devils Hole, seasonal thresholds for water temperature and food availability are defined to quantify the optimal recruitment window for the Devils Hole pupfish (Cyprinodon diabolis). At Travertine Springs, physical thresholds of water depth, velocity, and temperature are used to define the spatial extent of the preferred habitat of several threatened macroinvertebrate species. In both systems, mechanistic models are developed to predict the response of those physical thresholds to changing environmental conditions informed by climate change scenarios and potential changes in water availability. By examining the temporal and spatial response of targeted physical parameters to alternative scenarios, we can assess potential ecosystem impacts without direct measurement of ecological processes.

  11. Radioactivity in the Canadian aquatic environment

    International Nuclear Information System (INIS)

    Sources of radionuclides arising from natural anthropogenic processes as well as technologically enhanced natural radiation are discussed. Transport, distribution and behaviour of these radionuclides in aquatic systems are influenced by physical, chemical, biological and geological processes and conditions in freshwater and marine environments. Dosimetry of aquatic organisms, as well as various methods of measuring dose rate are presented. Effects of ionizing radiation (acute and chronic exposure) on aquatic organisms, populations and ecosystems are reviewed. This review covers the entire spectrum of the aquatic environment. Results of many studies are summarized. 300+ refs

  12. Habitat Use Database - Groundfish Essential Fish Habitat (EFH) Habitat Use Database (HUD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Habitat Use Database (HUD) was specifically designed to address the need for habitat-use analyses in support of groundfish EFH, HAPCs, and fishing and...

  13. Ghost of habitat past: historic habitat affects the contemporary distribution of giant garter snakes in a modified landscape.

    Science.gov (United States)

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2014-01-01

    Historic habitat conditions can affect contemporary communities and populations, but most studies of historic habitat are based on the reduction in habitat extent or connectivity. Little is known about the effects of historic habitat on contemporary species distributions when historic habitat has been nearly completely removed, but species persist in a highly altered landscape. More than 93% of the historic wetlands in the Central Valley of California, USA, have been drained and converted to agricultural and other uses, but agricultural wetlands, such as rice and its supporting infrastructure of canals, allow some species to persist. Little is known about the distribution of giant garter snakes Thamnophis gigas, a rare aquatic snake species inhabiting this predominantly agricultural landscape, or the variables that affect where this species occurs. We used occupancy modeling to examine the distribution of giant garter snakes at the landscape scale in the Sacramento Valley (northern portion of the Central Valley) of California, with an emphasis on the relative strength of historic and contemporary variables (landscape-scale habitat, local microhabitat, vegetation composition and relative prey counts) for predicting giant garter snake occurrence. Proximity to historic marsh best explained variation in the probability of occurrence of giant garter snakes at the landscape scale, with greater probability of occurrence near historic marsh. We suspect that the importance of distance to historic marsh represents dispersal limitations of giant garter snakes. These results suggest that preserving and restoring areas near historic marsh, and minimizing activities that reduce the extent of marsh or marsh-like (e.g. rice agriculture, canal) habitats near historic marsh may be advantageous to giant garter snakes.

  14. Habitat monitoring needs for Arapaho NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is the refuge's ideas on what level of monitoring is needed for each habitat objective. Habitat objectives include riparian habitat, wetland habitat,...

  15. Habitat architecture influencing microcrustaceans composition: a case study on freshwater Cladocera (Crustacea Branchiopoda).

    Science.gov (United States)

    Debastiani-Júnior, J R; Elmoor-Loureiro, L M A; Nogueira, M G

    2016-02-01

    Environmental complexity is considered a key factor for diversity enhancement in aquatic ecosystems. Macrophyte stands are a major contributor for this complexity due to their differential architectures. Nevertheless, the influence of distinct aquatic habitat architectures (with different types of macrophytes or without them) on microcrustaceans' taxa composition, usually found in macrophyte colonized water bodies, is underexplored in limnological studies. The main objective of this study was to analyze this influence by comparing the Cladocera composition among four habitat architectures: (1) fluctuant macrophytes, (2) rooted emergent macrophytes, (3) submerged macrophytes and (4) the limnetic zone of oxbow lakes associated to a large subtropical reservoir. Wide compositional variation was observed. Fluctuant macrophytes exhibited the richest Cladocera assemblage, dominated by Chydoridae. Submerged and rooted emergent macrophytes had the most similar assemblages between them. The most distinctive fauna was found in the limnetic zone, dominated by Bosminidae. Probable differences in resource availability in each sampled habitat architecture are considered as the driving factor for the Cladocera composition variation. We concluded that for a complete inventory of a given local fauna, it is imperative to take into account the aquatic habitat architecture, including macrophyte stands, in the data sampling design. PMID:26909628

  16. Biodiversity enhances ecosystem multifunctionality across trophic levels and habitats.

    Science.gov (United States)

    Lefcheck, Jonathan S; Byrnes, Jarrett E K; Isbell, Forest; Gamfeldt, Lars; Griffin, John N; Eisenhauer, Nico; Hensel, Marc J S; Hector, Andy; Cardinale, Bradley J; Duffy, J Emmett

    2015-04-24

    The importance of biodiversity for the integrated functioning of ecosystems remains unclear because most evidence comes from analyses of biodiversity's effect on individual functions. Here we show that the effects of biodiversity on ecosystem function become more important as more functions are considered. We present the first systematic investigation of biodiversity's effect on ecosystem multifunctionality across multiple taxa, trophic levels and habitats using a comprehensive database of 94 manipulations of species richness. We show that species-rich communities maintained multiple functions at higher levels than depauperate ones. These effects were stronger for herbivore biodiversity than for plant biodiversity, and were remarkably consistent across aquatic and terrestrial habitats. Despite observed tradeoffs, the overall effect of biodiversity on multifunctionality grew stronger as more functions were considered. These results indicate that prior research has underestimated the importance of biodiversity for ecosystem functioning by focusing on individual functions and taxonomic groups.

  17. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S.; Nottelman, H.

    1997-01-01

    The Biology Team of ESH-20 (the Ecology Group) at Los Alamos National Laboratory (LANL) has collected samples from the stream within Sandia Canyon since the summer of 1990. These field studies measure water quality parameters and collect aquatic macroinvertebrates from sampling sites within the upper canyon stream. Reports by Bennett and Cross discuss previous aquatic studies in Sandia Canyon. This report updates and expands the previous findings. The Biology Team collected water quality data and aquatic macroinvertebrates monthly at three sampling stations within Sandia Canyon in 1995. The two upstream stations occur near a cattail (Typha latifolia) dominated marsh downstream from outfalls that discharge industrial and sanitary waste effluent into the stream, thereby maintaining year-round flow. The third station is approximately 1.5 miles downstream from the outfalls within a mixed conifer forest. All water chemistry parameters measured in Sandia Canyon during 1995 fell within acceptable State limits and scored in the {open_quotes}good{close_quotes} or {open_quotes}excellent{close_quotes} ranges when compared to an Environmental Quality Index. However, aquatic macroinvertebrates habitats have been degraded by widespread erosion, channelization, loss of wetlands due to deposition and stream lowering, scour, limited acceptable substrates, LANL releases and spills, and other stressors. Macroinvertebrate communities at all the stations had low diversities, low densities, and erratic numbers of individuals. These results indicate that although the stream possesses acceptable water chemistry, it has reduced biotic potential. The best developed aquatic community occurs at the sampling station with the best habitat and whose downstream location partially mitigates the effects of upstream impairments.

  18. Aquatic Therapy: A Viable Therapeutic Recreation Intervention.

    Science.gov (United States)

    Broach, Ellen; Dattilo, John

    1996-01-01

    Reviews literature on the effects of aquatic therapy (swimming and exercise) to improve function. Research shows that aquatic therapy has numerous psychological and physical benefits, and it supports the belief that participation can provide a realistic solution to maintaining physical fitness and rehabilitation goals while engaging in enjoyable…

  19. Purification of Water by Aquatic Plants

    OpenAIRE

    Morimitsu, Katsuhito; Kawahigashi, Tatsuo

    2013-01-01

    [Abstract] Water quality purification of many water systems including those occurring in rivers depends to a great degree on water quality purification activities of aquatic plants and microbes. This paper presents a discussion of results, based on laboratory experiments, of purification by aquatic plants.

  20. Estimating Aquatic Insect Populations. Introduction to Sampling.

    Science.gov (United States)

    Chihuahuan Desert Research Inst., Alpine, TX.

    This booklet introduces high school and junior high school students to the major groups of aquatic insects and to population sampling techniques. Chapter 1 consists of a short field guide which can be used to identify five separate orders of aquatic insects: odonata (dragonflies and damselflies); ephemeroptera (mayflies); diptera (true flies);…

  1. Control of Fish and Aquatic Plants.

    Science.gov (United States)

    Hesser, R. B.; And Others

    This agriculture extension service publication from Pennsylvania State University is a handbook for the water body manager. The bulk of the contents deals with aquatic plant control. The different types of aquatic plants, their reproduction and growth, and their role in the ecology of the water body are introduced in this main section. Also, the…

  2. Spatial Pattern Dynamics in Aquatic Ecosystem Modelling

    NARCIS (Netherlands)

    Hong Li

    2009-01-01

    In this thesis, several modelling approaches are explored to represent spatial pattern dynamics of aquatic populations in aquatic ecosystems by the combination of models, knowledge and data in different scales. It is shown that including spatially distributed inputs retrieved from Remote Sensing i

  3. Phytoremediation potential of aquatic macrophyte, Azolla.

    Science.gov (United States)

    Sood, Anjuli; Uniyal, Perm L; Prasanna, Radha; Ahluwalia, Amrik S

    2012-03-01

    Aquatic macrophytes play an important role in the structural and functional aspects of aquatic ecosystems by altering water movement regimes, providing shelter to fish and aquatic invertebrates, serving as a food source, and altering water quality by regulating oxygen balance, nutrient cycles, and accumulating heavy metals. The ability to hyperaccumulate heavy metals makes them interesting research candidates, especially for the treatment of industrial effluents and sewage waste water. The use of aquatic macrophytes, such as Azolla with hyper accumulating ability is known to be an environmentally friendly option to restore polluted aquatic resources. The present review highlights the phytoaccumulation potential of macrophytes with emphasis on utilization of Azolla as a promising candidate for phytoremediation. The impact of uptake of heavy metals on morphology and metabolic processes of Azolla has also been discussed for a better understanding and utilization of this symbiotic association in the field of phytoremediation. PMID:22396093

  4. Coastal Resources Atlas: Long Island: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sensitive/rare coastal plants and submerged aquatic vegetation (SAV) for Long Island, New York. Vector...

  5. Plant Habitat (PH)

    Science.gov (United States)

    Onate, Bryan

    2016-01-01

    The International Space Station (ISS) will soon have a platform for conducting fundamental research of Large Plants. Plant Habitat (PH) is designed to be a fully controllable environment for high-quality plant physiological research. PH will control light quality, level, and timing, temperature, CO2, relative humidity, and irrigation, while scrubbing ethylene. Additional capabilities include leaf temperature and root zone moisture and oxygen sensing. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs. There will be several internal cameras (visible and IR) to monitor and record plant growth and operations.

  6. Applications of a broad-spectrum tool for conservation and fisheries analysis: aquatic gap analysis

    Science.gov (United States)

    McKenna, James E.; Steen, Paul J.; Lyons, John; Stewart, Jana S.

    2009-01-01

    Natural resources support all of our social and economic activities, as well as our biological existence. Humans have little control over most of the physical, biological, and sociological conditions dictating the status and capacity of natural resources in any particular area. However, the most rapid and threatening influences on natural resources typically are anthropogenic overuse and degradation. In addition, living natural resources (i.e., organisms) do not respect political boundaries, but are aware of their optimal habitat and environmental conditions. Most organisms have wider spatial ranges than the jurisdictional boundaries of environmental agencies that deal with them; even within those jurisdictions, information is patchy and disconnected. Planning and projecting effects of ecological management are difficult, because many organisms, habitat conditions, and interactions are involved. Conservation and responsible resource use involves wise management and manipulation of the aspects of the environment and biological communities that can be effectively changed. Tools and data sets that provide new insights and analysis capabilities can enhance the ability of resource managers to make wise decisions and plan effective, long-term management strategies. Aquatic gap analysis has been developed to provide those benefits. Gap analysis is more than just the assessment of the match or mis-match (i.e., gaps) between habitats of ecological value and areas with an appropriate level of environmental protection (e.g., refuges, parks, preserves), as the name suggests. Rather, a Gap Analysis project is a process which leads to an organized database of georeferenced information and previously available tools to examine conservation and other ecological issues; it provides a geographic analysis platform that serves as a foundation for aquatic ecological studies. This analytical tool box allows one to conduct assessments of all habitat elements within an area of interest

  7. THE APPLICATION OF SOME METHODS FOR COMPUTATION THE FLOWS FOR PROTECTION OF AQUATIC ECOSYSTEMS DOWNSTREAM OF RESERVOIR

    Directory of Open Access Journals (Sweden)

    TĂNASE ILEANA

    2014-03-01

    Full Text Available The modification of the natural flow regimes by different water intakes degrades river ecosystems by erosion, by altering physical habitat and sediment supply rate. Providing a "flow for aquatic ecosystem" implies a flow regime designed to maintain a river in some environmentally acceptable conditions. All components of the natural hydrological regime have ecological significance. However, maintaining the full spectrum of naturally flows which occurring in a river is normally impossible due to water resources development and changes in land use in the catchments. Therefore, the flow protection of aquatic ecosystems should be seen as a compromise between developments within the river basin on the one hand and the maintenance of river ecology on the other. In Romania, providing the flow for the protection of aquatic ecosystems is a very important issue in the complex process of ecological restoration. According to the "Programme of Measures" chapter, presented within the River Basin Management Plans, "for increase of aquatic biodiversity besides the re-naturation of landscape, restoring the natural processes namely an adequate hydrologic regime for the water uses and aquatic species and a functional link between river and floodplain through changes to the water management systems operation is required". The paper shows the results for the application of some methods for computing the flows for protection of aquatic ecosystems downstream of a reservoir.

  8. Habitat modeling and genetic signatures of postglacial recolonization for tidal estuaries

    Science.gov (United States)

    Dolby, G. A.; Jacobs, D. K.

    2014-12-01

    Pleistocene glacial cycles are a foremost influence on the genetic diversity and species distribution patterns observed today. Though much work has centered on biotic response to such climatic forcing, little of it has regarded estuarine or other aquatic coastal taxa whose habitat formation is a function of sea level, hydrography, and coastal geomorphology. These physical parameters required for habitat formation suggest that glacial cycles impart a significant effect on such taxa through glacially driven eustatic changes. Additionally, the steepened coastline and rainfall-limited Mediterranean climate suggest limited glacial habitat for estuarine species in southern and Baja California. Here we present GIS modeled habitat for tidal estuaries for three co-distributed estuarine fishes (Gillichthys mirabilis, Quietula y-cauda, Fundulus parvipinnis) since the last glacial maximum. Parameterization of sea level and slope enables biologically relevant temporal resolution of near-millennial scale. At lowstand our approach reveals two refuges along the coast at 1000km distance from each other, with habitat rapidly increasing 15 - 12 ka during meltwater pulse 1A. Habitat area peaked in the early Holocene and began decreasing with the current stillstand roughly 7 ka, probably as a result of coastal maturation towards less tidal systems. To target the postglacial recolonization process we applied discriminant function analysis to highly polymorphic microsatellite data to partition out the alleles associated with refuges identified a priori by habitat modeling. The frequencies of these alleles were calculated for all individuals at intervening populations and regressed against geographic distance. This analysis revealed nonlinear mixing curves, suggesting uneven allelic mixing efficiency along the coastline, perhaps as a result of differential habitat origination times as indicated by the habitat models. These results highlight the dynamism of estuarine habitat in recent

  9. Predation efficiency of Anopheles gambiae larvae by aquatic predators in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Nyindo Mramba

    2011-07-01

    Full Text Available Abstract Background The current status of insecticide resistance in mosquitoes and the effects of insecticides on non-target insect species have raised the need for alternative control methods for malaria vectors. Predation has been suggested as one of the important regulation mechanisms for malaria vectors in long-lasting aquatic habitats, but the predation efficiency of the potential predators is largely unknown in the highlands of western Kenya. In the current study, we examined the predation efficiency of five predators on Anopheles gambiae s.s larvae in 24 hour and semi- field evaluations. Methods Predators were collected from natural habitats and starved for 12 hours prior to starting experiments. Preliminary experiments were conducted to ascertain the larval stage most predated by each predator species. When each larval instar was subjected to predation, third instar larvae were predated at the highest rate. Third instar larvae of An. gambiae were introduced into artificial habitats with and without refugia at various larval densities. The numbers of surviving larvae were counted after 24 hours in 24. In semi-field experiments, the larvae were counted daily until they were all either consumed or had developed to the pupal stage. Polymerase chain reaction was used to confirm the presence of An. gambiae DNA in predator guts. Results Experiments found that habitat type (P P P P An. gambiae DNA was found in at least three out of ten midguts for all predator species. Gambusia affins was the most efficient, being three times more efficient than tadpoles. Conclusion These experiments provide insight into the efficiency of specific natural predators against mosquito larvae. These naturally occurring predators may be useful in biocontrol strategies for aquatic stage An. gambiae mosquitoes. Further investigations should be done in complex natural habitats for these predators.

  10. Distribution of aquatic insects in phumdis (floating island of Loktak Lake, Manipur, northeastern India

    Directory of Open Access Journals (Sweden)

    K. Takhelmayum

    2011-06-01

    Full Text Available A study was made on the temporal fluctuations of distribution of aquatic insects around Phumdi Live (PL, Phumdi Mixed (PM and Phumdi Dry (PD areas of Loktak Lake. Phumdis are a heterogeneous mass of soil, vegetation and organic matter. The study revealed the presence of predators, and the absence of herbivores and detritivores in both PL and PM, the PD area was totally devoid of insects. Although both the habitats supported the same predator groups hemiptera and odonata, diversity and density in terms of family and species were higher in PL than in PM. Temporal fluctuations revealed that the Shannon-Weiner’s Diversity Index values were highest in June for both PL (0.726 and PM (0.47. In both the sites the highest density was recorded in February. The relative abundance of hemiptera was higher than that of odonata in most of the months in PL. Phumdi Mixed was represented by one species of hemiptera only, in the month of February and dominated by odonates otherwise. Community composition of odonata larvae did not show any difference between the two habitats. Although the study revealed low diversity and density of insects in both sites, the PL community provided a better habitat to aquatic insects than that of PM. These are of value as fish food and in turn for fish production.

  11. Evaluating extinction in rare habitats: an essay

    Directory of Open Access Journals (Sweden)

    Camacho, A. I.

    2003-12-01

    Full Text Available Inference and estimation are the Achilles heel of many biological disciplines. The validation of results is the first step before taking any further decision. In Biodiversity studies the technical problems in validation are similar to those faced in other disciplines. The main difference with areas like medicine is that a validation error in the latter can easily take you to court, but very few responsibilities apart from moral or ethical ones generally derive from a faulty estimation or validation in Biodiversity. However, many political decisions concerning conservation issues, which in many cases affect powerful economic interests depend on the reliability of those biodiversity studies. Getting good, reliable information is not always easy, and this explains in part, the success of critical voices like Simon (1998 and Lomborg (2001. New methodologies like Population Viability Analysis has been developed to take advantage of the potential information contained in periodical sampling. We apply it to a peculiar and difficult to study fauna: the fauna of the aquatic subterranean environment. Lack of regular information and scarcity of the fauna due to difficulty to reach their proper habitat are the main problems that confront this analysis. However, despite its limitations, the analysis points towards a need to better understand the structure of the subterranean habitat from “an animal point of view” and the need of more regular sampling at the same time that the other environmental parameters are taken.

    La inferencia y la estima son el talón de Aquiles de muchas disciplinas biológicas. La validación de resultados es el primer paso antes de tomar decisiones ulteriores. En estudios de Biodiversidad los problemas técnicos de validación son semejantes a los que se enfrentan otras disciplinas. La principal diferencia con áreas como Medicina es que un error en validación en ésta última puede terminar fácilmente en el juzgado

  12. Human Exploitation of Aquatic Landscapes. Editorial

    Directory of Open Access Journals (Sweden)

    Ricardo Fernandes

    2014-11-01

    Full Text Available Aquatic landscapes such as rivers, lakes, and seas played an important role in past human behaviour, affecting modes of subsistence, patterns of mobility, access to material resources, and technological choices and their developments. The interaction with aquatic landscapes was also influential in the establishment of economic and social structures and in the formation of communal identities. The aim of this special themed issue of Internet Archaeology is to contribute to a better understanding of different forms of human interaction with aquatic landscapes.

  13. Aquatic invasive species: Lessons from cancer research

    Science.gov (United States)

    Sepulveda, Adam; Ray, Andrew; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Gresswell, Robert E.; Gross, Jackson A.; Kershner, Jeffrey L.

    2014-01-01

    Aquatic invasive species are disrupting ecosystems with increasing frequency. Successful control of these invasions has been rare: Biologists and managers have few tools for fighting aquatic invaders. In contrast, the medical community has long worked to develop tools for preventing and fighting cancer. Its successes are marked by a coordinated research approach with multiple steps: prevention, early detection, diagnosis, treatment options and rehabilitation. The authors discuss how these steps can be applied to aquatic invasive species, such as the American bullfrog (Lithobates catesbeianus), in the Northern Rocky Mountain region of the United States, to expedite tool development and implementation along with achievement of biodiversity conservation goals.

  14. A Mixed Picture of AQUATIC PRODUCTS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Aquatic products constitute an important part of China's international trade in agricultural products with the strongest competitiveness for export.The aquatic products industry of apparent competitive edge has maintained a considerable trade surplus despite the general trend of trade deficit among agricultural products in recent years.Nevertheless,the great changes taking place in the global economic and trade pattern in late years have given rise to the increasing uncertainties of the supply and demand as well as the price in the international aquatic products market.

  15. Community photosynthesis of aquatic macrophytes

    DEFF Research Database (Denmark)

    Binzer, T.; Sand-Jensen, K.; Middelboe, A. L.

    2006-01-01

    We compared 190 photosynthesis-irradiance (P-E) experiments with single- and multispecies communities of macroalgae and vascular plants from freshwater and marine habitats. We found a typical hyperbolic P-E relation in all communities and no sign of photosaturation or photoinhibition...... of photosynthesis at the highest irradiances of about 2,000 mmol m22 s21. Macrophyte communities displayed much higher maximum gross production (GPmax), respiration, and light compensation point than separate phytoelements because of the multilayered structure and extensive self-shading in the communities, whereas...... light use efficiency at low irradiance (a) was the same. Although GPmax and a varied extensively among the 190 communities, their upper limits increased linearly and predictably with community absorption reaching 26.3 mmol m22 s21 O2 and 0.090 mol mol21 photon at 100% absorption. The upper limit...

  16. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, November 1993--October 1994

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S.

    1995-08-01

    The Ecological Studies Team (EST) of ESH-20 at Los Alamos National Laboratory (LANL) has collected samples from the stream within Sandia Canyon since the summer of 1990. These field studies gather water quality measurements and collect aquatic macroinvertebrates from permanent sampling sites. Reports by Bennett (1994) and Cross (1994) discuss previous EST aquatic studies in Sandia Canyon. This report updates and expands those findings. EST collected water quality data and aquatic macroinvertebrates at five permanent stations within the canyon from November 1993 through October 1994. The two upstream stations are located below outfalls that discharge industrial and sanitary waste effluent into the stream, thereby maintaining year-round flow. Some water quality parameters are different at the first three stations from those expected of natural streams in the area, indicating degraded water quality due to effluent discharges. The aquatic habitat at the upper stations has also been degraded by sedimentation and channelization. The macroinvertebrate communities at these stations are characterized by low diversities and unstable communities. In contrast, the two downstream stations appear to be in a zone of recovery, where water quality parameters more closely resemble those found in natural streams of the area. The two lower stations have increased macroinvertebrate diversity and stable communities, further indications of downstream water quality improvement.

  17. Anatomy of the root of eight species of emergent aquatic macrophytes from the upper Paraná river, Paraná State, Brazil floodplain - doi: 10.4025/actascibiolsci.v32i3.5509 Anatomy of the root of eight species of emergent aquatic macrophytes from the upper Paraná river, Paraná State, Brazil floodplain - doi: 10.4025/actascibiolsci.v32i3.5509

    Directory of Open Access Journals (Sweden)

    Angela Maria Marques Sanches Marques

    2010-09-01

    Full Text Available The upper Paraná River floodplain is characterized by the existence of several aquatic and transitional habitats between the aquatic and terrestrial environment, influencing the presence and distribution of aquatic macrophytes. Samples were taken from different places and permanent slides were prepared for analysis and capture of images with the objective of comparing the anatomy of the roots of eight species of emergent aquatic macrophytes. The species feature uniseriate epidermis with narrow and long cells, cortex composed of uniseriate or biseriate exodermis, with or without thickening, aerenchyma with great gaps, uniseriate endodermis, with or without thickening, continuous or interrupted pericycle, and central cylinder with variable number of xylem poles.The upper Paraná River floodplain is characterized by the existence of several aquatic and transitional habitats between the aquatic and terrestrial environment, influencing the presence and distribution of aquatic macrophytes. Samples were taken from different places and permanent slides were prepared for analysis and capture of images with the objective of comparing the anatomy of the roots of eight species of emergent aquatic macrophytes. The species feature uniseriate epidermis with narrow and long cells, cortex composed of uniseriate or biseriate exodermis, with or without thickening, aerenchyma with great gaps, uniseriate endodermis, with or without thickening, continuous or interrupted pericycle, and central cylinder with variable number of xylem poles.

  18. Dietary supplements for aquatic sports.

    Science.gov (United States)

    Derave, Wim; Tipton, Kevin D

    2014-08-01

    Many athletes use dietary supplements, with use more prevalent among those competing at the highest level. Supplements are often self-prescribed, and their use is likely to be based on an inadequate understanding of the issues at stake. Supplementation with essential micronutrients may be useful when a diagnosed deficiency cannot be promptly and effectively corrected with food-based dietary solutions. When used in high doses, some supplements may do more harm than good: Iron supplementation, for example, is potentially harmful. There is good evidence from laboratory studies and some evidence from field studies to support health or performance benefits from appropriate use of a few supplements. The available evidence from studies of aquatic sports is small and is often contradictory. Evidence from elite performers is almost entirely absent, but some athletes may benefit from informed use of creatine, caffeine, and buffering agents. Poor quality assurance in some parts of the dietary supplements industry raises concerns about the safety of some products. Some do not contain the active ingredients listed on the label, and some contain toxic substances, including prescription drugs, that can cause health problems. Some supplements contain compounds that will cause an athlete to fail a doping test. Supplement quality assurance programs can reduce, but not entirely eliminate, this risk.

  19. Use of Aeromonas spp. as general indicators of antimicrobial susceptibility among bacteria in aquatic environments in Thailand

    OpenAIRE

    Masaru eUsui; Chie eTagaki; Akira eFukuda; Torahiko eOkubo; Chanchai eBoonla; Satoru eSuzuki; Kanako eSeki; Hideshige eTakada; Yutaka eTamura

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria (ARB), and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya Riv...

  20. Effects of co-habitation between Anopheles gambiae s.s. and Culex quinquefasciatus aquatic stages on life history traits

    OpenAIRE

    Kweka Eliningaya J; Zhou Goufa; Beilhe Leila B; Dixit Amruta; Afrane Yaw; Gilbreath Thomas M; Munga Stephen; Nyindo Mramba; Githeko Andrew K; Yan Guiyun

    2012-01-01

    Abstract Background The effective measures for the control of malaria and filariasis vectors can be achieved by targeting immature stages of anopheline and culicine mosquitoes in productive habitat. To design this strategy, the mechanisms (like biotic interactions with conspecifc and heterospecific larvae) regulating mosquito aquatic stages survivorship, development time and the size of emerging adults should be understood. This study explored the effect of co-habitation between An. gambiae s...

  1. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Dawley, Earl M.; Coleman, Andre M.

    2010-08-01

    This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary.

  2. Amazonian freshwater habitats experiencing environmental and socioeconomic threats affecting subsistence fisheries.

    Science.gov (United States)

    Alho, Cleber J R; Reis, Roberto E; Aquino, Pedro P U

    2015-09-01

    Matching the trend seen among the major large rivers of the globe, the Amazon River and its tributaries are facing aquatic ecosystem disruption that is affecting freshwater habitats and their associated biodiversity, including trends for decline in fishery resources. The Amazon's aquatic ecosystems, linked natural resources, and human communities that depend on them are increasingly at risk from a number of identified threats, including expansion of agriculture; cattle pastures; infrastructure such as hydroelectric dams, logging, mining; and overfishing. The forest, which regulates the hydrological pulse, guaranteeing the distribution of rainfall and stabilizing seasonal flooding, has been affected by deforestation. Flooding dynamics of the Amazon Rivers are a major factor in regulating the intensity and timing of aquatic organisms. This study's objective was to identify threats to the integrity of freshwater ecosystems, and to seek instruments for conservation and sustainable use, taking principally fish diversity and fisheries as factors for analysis. PMID:25572836

  3. Antimicrobial activity and identification of potential antimicrobial compounds from aquatic pteridophyte, Azolla microphylla Kaulf.

    Science.gov (United States)

    Abraham, G; Yadav, R K; Kaushik, G K

    2015-04-01

    Azolla microphylla Kaulf. is an aquatic nitrogen fixing pteridophyte commonly found in aquatic habitats including paddy fields. Methanolic extract of the fronds of A. microphylla was subjected to partial purification by solvent partitioning with diethyl ether and ethyl acetate followed by hydrolysis, and further partitioning with ethyl acetate. The two fractions, thus obtained were tested for antibacterial activity. It was observed that the ethyl acetate fraction inhibited the growth of the pathogenic bacterium Xanthomonas oryzae. The GC-MS analysis of the ethyl acetate fraction showed several prominent peaks with retention time ranging from 8.83 to 45.54 min. A comparison of these peaks with the GC-MS libraries revealed that it could be eicosenes and heptadecanes with potential of antimicrobial activity. PMID:26011985

  4. Efficacy of sunlight-activatable porphyrin formulates on larvae of Anopheles gambiae M and S molecular forms and An. arabiensis: a potential novel biolarvicide for integrated malaria vector control.

    Science.gov (United States)

    Fabris, Clara; Ouédraogo, Robert Kossivi; Coppellotti, Olimpia; Dabiré, Roch K; Diabaté, Abdoulaye; Di Martino, Piera; Guidolin, Laura; Jori, Giulio; Lucantoni, Leonardo; Lupidi, Giulio; Martena, Valentina; Sawadogo, Simon P; Soncin, Marina; Habluetzel, Annette

    2012-09-01

    Biolarvicides, such as microbial formulations based on Bacillus thuringiensis and B. sphaericus, have been found to be highly effective against mosquito larvae and are currently employed as eco-friendly alternatives to synthetic chemical insecticides for vector control. Recently, a porphyrin of natural origin has been suggested as a sunlight-activatable larvicide against the dengue vector Aedes aegypti. In order to validate the approach for the control of the malaria vector, we tested the photo-larvicidal activity of a novel porphyrin, namely meso-tri(N-methyl-pyridyl), mono(N-dodecyl-pyridyl)porphine, C12, associated with two specifically selected carriers, against Anopheles gambiae s.s. and An. arabiensis larvae, both laboratory reared and collected from malaria endemic sites in Burkina Faso. Both C12-porphyrin formulates, when administered to larvae at a 50μM porphyrin dose, were accumulated in the alimentary canal. Subsequent exposure of the porphyrin-loaded larvae to sunlight for short times (0.5-3h) led to a complete mortality. The high efficacy exhibited by a "foodstuff" porphyrin formulate also in the presence of typical larval food particles opens promising perspectives for the development of an effective photocidal larvicide.

  5. Clay Animals and Their Habitats

    Science.gov (United States)

    Adamson, Kay

    2010-01-01

    Creating clay animals and their habitats with second-grade students has long been one of the author's favorite classroom activities. Students love working with clay and they also enjoy drawing animal homes. In this article, the author describes how the students created a diorama instead of drawing their clay animal's habitat. This gave students…

  6. Habitat specialization through germination cueing

    DEFF Research Database (Denmark)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen; Bruun, Hans Henrik

    2013-01-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently...

  7. Summer Home Range Size and Habitat Use by River Otters in Ohio

    Directory of Open Access Journals (Sweden)

    David A. Helon

    2004-01-01

    Full Text Available Reintroduced river otters (Lontra canadensis are an important component of Ohio’s biological diversity, and are a key indicator of wetland and watershed health and quality. However, few data are available on their home range sizes and habitat use. We monitored river otters using radio-telemetry in the Killbuck Watershed, in northeastern Ohio, during 2002 and 2003 to determine home range and habitat use. Overall, mean home range size was 802.4 ha (range = 84.5–3,376.3, SE = 448.2 for female river otters and 1,101.7 ha (range = 713.8–1,502.6, SE = 102.2 for male river otters. Home range size of female and male river otters did not differ in 2002 (P = 0.763, but males had larger home range size than females during 2003 (P = 0.001. Based on compositional analysis, habitat use differed in proportion to availability of the 5 habitat types available in the study area (marsh, wet meadow, riparian/floodplain, open water, and flooded upland (P < 0.0001. Overall, river otters used marsh habitat with a diverse association of floating aquatics and emergent vegetation in greater proportion than was available. Knowledge and understanding of river otter habitat use and home range size in Ohio will help managers identify habitats suitable for river otters in the Midwestern United States.

  8. Nitrous oxide emission by aquatic macrofauna

    DEFF Research Database (Denmark)

    Stief, Peter; Poulsen, Morten; Nielsen, Lars Peter;

    2009-01-01

      A large variety of aquatic animals was found to emit the potent greenhouse gas nitrous oxide when nitrate was present in the environment. The emission was ascribed to denitrification by ingested bacteria in the anoxic animal gut, and the exceptionally high N2O-to-N2 production ratio suggested...... delayed induction of the last step of denitrification. Filter- and deposit-feeding animal species showed the highest rates of nitrous oxide emission and predators the lowest, probably reflecting the different amounts of denitrifying bacteria in the diet. We estimate that nitrous oxide emission by aquatic...... animals is quantitatively important in nitraterich aquatic environments like freshwater, coastal marine, and deep-sea ecosystems. The contribution of this source to overall nitrous oxide emission from aquatic environments might further increase because of the projected increase of nitrate availability...

  9. Submerged Aquatic Vegetation (SAV) - Volusia County Seagrass

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Aquatic vegetation in Volusia County. DEP SEA_GRASSES This polygon GIS data set represents a compilation of statewide seagrass data from various source agencies and...

  10. Nonindigenous Aquatic Species Database Marine Fishes

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Nonindigenous Aquatic Species Database (NAS) information resource is an established central repository for spatially referenced biogeographic accounts of...

  11. Freshwater aquatic plant biomass production in Florida

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, K.R.; Sutton, D.L.; Bowes, G.

    1983-01-01

    About 8% (1.2 million ha) of the total surface area of Florida is occupied by freshwater. Many of these water bodies are eutrophic. Nutrients present in these water bodies can be potentially used to culture aquatic plants as a possible feedstock for methane production. This paper summarizes the results of known research findings on biomass production potential of freshwater aquatic plants in Florida and identifies key research needs to improve the quality and quantity of biomass yields. Among floating aquatic plants, biomass yield potential was in the order of water-hyacinth > water lettuce > pennywort > salvinia > duckweed > azolla. Pennywort, duckweed, and azolla appear to perform well during the cooler months compared to other aquatic plants. Among emergent plants, biomass yield potential was in the order of southern wild rice > cattails > soft rush > bulrush. Cultural techniques, nutrient management, and environmental factors influencing the biomass yields were discussed. 68 references.

  12. Nitrous oxide emission by aquatic macrofauna

    Science.gov (United States)

    Stief, Peter; Poulsen, Morten; Nielsen, Lars Peter; Brix, Hans; Schramm, Andreas

    2009-01-01

    A large variety of aquatic animals was found to emit the potent greenhouse gas nitrous oxide when nitrate was present in the environment. The emission was ascribed to denitrification by ingested bacteria in the anoxic animal gut, and the exceptionally high N2O-to-N2 production ratio suggested delayed induction of the last step of denitrification. Filter- and deposit-feeding animal species showed the highest rates of nitrous oxide emission and predators the lowest, probably reflecting the different amounts of denitrifying bacteria in the diet. We estimate that nitrous oxide emission by aquatic animals is quantitatively important in nitrate-rich aquatic environments like freshwater, coastal marine, and deep-sea ecosystems. The contribution of this source to overall nitrous oxide emission from aquatic environments might further increase because of the projected increase of nitrate availability in tropical regions and the numeric dominance of filter- and deposit-feeders in eutrophic ecosystems. PMID:19255427

  13. Effect of Aquatic Immersion on Static Balance

    OpenAIRE

    Louder, Talin J.

    2013-01-01

    Objective To quantitatively assess measures of static balance and limits of stability (LOS) in an aquatic environment compared to on land. Methods Fifteen healthy, young adults (23 + or - 2 years) performed 90 s static balance trials on land and aquatic immersion at two different depths (greater trochanter, xiphoid process). Measures of 95% ellipse area and center of pressure (CoP) mean velocity were computed from the force data. Additionally, participants completed a visual analog scale (VAS...

  14. Aquatic bird disease and mortality as an indicator of changing ecosystem health

    Science.gov (United States)

    Newman, Scott H.; Chmura, Aleksei; Converse, Kathy; Kilpatrick, A. Marm; Patel, Nikkita; Lammers, Emily; Daszak, Peter

    2007-01-01

    We analyzed data from pathologic investigations in the United States, collected by the USGS National Wildlife Health Center between 1971 and 2005, into aquatic bird mortality events. A total of 3619 mortality events was documented for aquatic birds, involving at least 633 708 dead birds from 158 species belonging to 23 families. Environmental causes accounted for the largest proportion of mortality events (1737 or 48%) and dead birds (437 258 or 69%); these numbers increased between 1971 and 2000, with biotoxin mortalities due to botulinum intoxication (Types C and E) being the leading cause of death. Infectious diseases were the second leading cause of mortality events (20%) and dead birds (20%), with both viral diseases, including duck plague (Herpes virus), paramyxovirus of cormorants (Paramyxovirus PMV1) and West Nile virus (Flavivirus), and bacterial diseases, including avian cholera (Pasteurella multocida), chlamydiosis (Chalmydia psittici), and salmonellosis (Salmonella sp.), contributing. Pelagic, coastal marine birds and species that use marine and freshwater habitats were impacted most frequently by environmental causes of death, with biotoxin exposure, primarily botulinum toxin, resulting in mortalities of both coastal and freshwater species. Pelagic birds were impacted most severely by emaciation and starvation, which may reflect increased anthropogenic pressure on the marine habitat from over-fishing, pollution, and other factors. Our study provides important information on broad trends in aquatic bird mortality and highlights how long-term wildlife disease studies can be used to identify anthropogenic threats to wildlife conservation and ecosystem health. In particular, mortality data for the past 30 yr suggest that biotoxins, viral, and bacterial diseases could have impacted >5 million aquatic birds.

  15. Nutrition and training adaptations in aquatic sports.

    Science.gov (United States)

    Mujika, Iñigo; Stellingwerff, Trent; Tipton, Kevin

    2014-08-01

    The adaptive response to training is determined by the combination of the intensity, volume, and frequency of the training. Various periodized approaches to training are used by aquatic sports athletes to achieve performance peaks. Nutritional support to optimize training adaptations should take periodization into consideration; that is, nutrition should also be periodized to optimally support training and facilitate adaptations. Moreover, other aspects of training (e.g., overload training, tapering and detraining) should be considered when making nutrition recommendations for aquatic athletes. There is evidence, albeit not in aquatic sports, that restricting carbohydrate availability may enhance some training adaptations. More research needs to be performed, particularly in aquatic sports, to determine the optimal strategy for periodizing carbohydrate intake to optimize adaptations. Protein nutrition is an important consideration for optimal training adaptations. Factors other than the total amount of daily protein intake should be considered. For instance, the type of protein, timing and pattern of protein intake and the amount of protein ingested at any one time influence the metabolic response to protein ingestion. Body mass and composition are important for aquatic sport athletes in relation to power-to-mass and for aesthetic reasons. Protein may be particularly important for athletes desiring to maintain muscle while losing body mass. Nutritional supplements, such as b-alanine and sodium bicarbonate, may have particular usefulness for aquatic athletes' training adaptation.

  16. Aquatic arsenic: phytoremediation using floating macrophytes.

    Science.gov (United States)

    Rahman, M Azizur; Hasegawa, H

    2011-04-01

    Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. PMID:21435676

  17. Larval Habitats Diversity and Distribution of the Mosquito (Diptera: Culicidae) Species in the Republic of Moldova.

    Science.gov (United States)

    Sulesco, Tatiana M; Toderas, Lidia G; Uspenskaia, Inga G; Toderas, I K

    2015-11-01

    A countrywide field survey of immature mosquitoes was conducted in Moldova with the aim to evaluate the Culicidae species composition in different larval habitats and their distribution in the country. In total, 259 potential larval habitats were sampled in the 53 localities, resulting in 9,456 specimens. Twenty species belonging to the genera Anopheles, Aedes, Culex, Culiseta, and Uranotaenia were collected. Mean species richness in aquatic habitats ranged from 1.00 to 4.00, and, for example, was higher in swamps, flood plains, ditches, and large ground pools and lower in rivers, streams, tree-holes, and containers. Six mosquito species were identified only in a single type of aquatic habitat. Anopheles maculipennis s.l., Culex pipiens pipiens L., and Culex modestus Ficalbi were the most abundant and distributed species representing over 80% of the identified specimens. Three, four, and five associated species were recorded from 23.5% of mosquito-positive aquatic habitats. Our findings demonstrate the co-occurrence of Cx. p. pipiens and Culex torrentium Martini in natural and rural environments. It is concluded that the study area has undergone a dramatic ecological change since the previous studies in the 1950s, causing the near extinction of Culex theileri Theobald from Moldova. An. maculipennis s.l. larval abundance, reduced by the DDT control of the adults in the 1950s, had returned to those of the 1940s. Restoration of An. maculipennis s.l. abundance in combination with imported malaria cases constitute a risk of the reintroduction of malaria transmission in Moldova.

  18. Combining Data to Assess of the Habitat Suitability of Patches of Streambed

    Science.gov (United States)

    Wicks, C. M.; Aley, T.; Ashley, D.; Noltie, D.

    2011-12-01

    Many of the aquatic animals that live in cave streams are threatened, endangered, or endemic. Management plans needed to conserve the aquatic ecosystems within which these animals live must be based on an understanding of the food webs, life histories, and habitat suitability. However, for many of these ecosystems, there is very little information about the food webs, life histories, or habitat suitability. If information is available, that information is frequently incomplete. One aspect of habitat suitability is the stability of the streambed sediment. Sediment that can be scoured over a wide range of hydrologic conditions is not suitable habitat as scour events disrupt the streambed sediment resulting in dispersal or possibly death of the animals; whereas, sediment that cannot be scoured would be suitable habitat. Assessing sediment stability requires hydrologic and sedimentologic data and assessing habitat suitability requires population consensus data. Rarely are the three disparate sets of data collected. Our objective was to develop a method that can be used to assess streambed stability using disparate data sets. At locations along the cave streams for which we have conducted population consensuses and particle-size distribution data, we used the flow competence method to assess streambed stability. At each location, the depth of water that would result in scour of the sediment was calculated (a constant) and was compared to the measured or calculated depth of the water (a function of time). In absence of measured depth of water data, we used a numerical model of unsteady state flow along the two main stream channels to calculate the depth of water at each consensus location in each ecosystem. Habitat suitability was evaluated by comparing the presence or absence of animals at each consensus location with our understanding of the stability of the streambed at the same location. With a calibrated numerical model and water depth and sedimentologic data, this

  19. Is there a need for a '100 questions exercise' to enhance fisheries and aquatic conservation, policy, management and research? Lessons from a global 100 questions exercise on conservation of biodiversity.

    Science.gov (United States)

    Cooke, S J; Danylchuk, A J; Kaiser, M J; Rudd, M A

    2010-06-01

    Recent global and regional exercises have been undertaken to identify 100 questions of relevance to policy makers that, if answered, would improve decision making and conservation actions. These were intentionally broad, but all included themes and questions of relevance to aquatic and fisheries professionals (e.g. exploitation, habitat alteration, effectiveness of protected areas, migratory connectivity and environmental effects of aquaculture). Here, the content of the global 100 question exercise relevant to aquatic and fisheries issues is summarized and a critical analysis is provided. Many of the questions addressed in apparently unrelated themes and topics (e.g. terrestrial, agriculture and energy policy) have potential relevance to fisheries and aquatic habitats, which underlines the connectivity between terrestrial and aquatic realms. Given the intimate link between aquatic environmental problems and human activities (including culture and economics), greater understanding of the human dimension is required to inform decision making. Stakeholder perspectives need to be included as a core component of the fisheries management triangle (i.e. managing fish, habitat and people). The benefits and risks of conducting a global 100 questions exercise with an exclusive focus on questions of relevance to fisheries and aquatic practitioners are also considered. There is no question that evidence-based approaches to conservation are essential for addressing the many threats that face aquatic ecosystems and reverse the imperilment trends among ichthyofauna. It is still unclear, however, as to the extent to which 100 questions exercises will help to achieve conservation and management targets for aquatic resources. A global 100 questions exercise that focused on fisheries and aquatic issues would certainly help to generate interest and awareness sufficient to justify such an exercise. PMID:20557662

  20. Invasive lionfish use a diversity of habitats in Florida

    Science.gov (United States)

    Schofield, Pamela J.; Akins, Lad; Gregoire-Lucente, Denise R.; Pawlitz, Rachel J.

    2014-01-01

    Two species of lionfish (Pterois volitans and Pterois miles) are the first marine fishes known to invade and establish self-sustaining populations along the eastern seaboard of the United States. First documented off the coast of Florida in 1985, lionfish are now found along the Atlantic coast of the United States as well as in the Caribbean Sea and Gulf of Mexico. Although long-term effects of this invasion are not yet fully known, there is early evidence that lionfish are negatively impacting native marine life. The lionfish invasion raises questions about which types of habitat the species will occupy in its newly invaded ecosystem. In their native range, lionfish are found primarily on coral reefs but sometimes are found in other habitats such as seagrasses and mangroves. This fact sheet documents the diversity of habitat types in which invasive lionfish have been reported within Florida’s coastal waters, based on lionfish sightings recorded in the U.S. Geological Survey Nonindigenous Aquatic Species database (USGS-NAS).

  1. Steelhead Critical Habitat, Coast - NOAA [ds122

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Steelhead Critical Habitat as well as habitat type and quality in the Coastal California Steelhead ESUs (evolutionarily...

  2. Guam and the Northern Mariana Islands ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats and plants in Guam and the Northern Mariana Islands. Vector polygons in this...

  3. Southeast Alaska ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seagrass habitats in Southeast Alaska. Vector polygons in this data set represent locations of seagrass...

  4. Riparian Habitat - Product of 2 riparian habitat workshops

    Data.gov (United States)

    California Department of Resources — In two riparian habitat workshops held between 2001 and 2002, scientists and managers identified the need for determining the scope of a consistent and acceptable...

  5. Physical habitat classification and instream flow modeling to determine habitat availability during low-flow periods, North Fork Shenandoah River, Virginia

    Science.gov (United States)

    Krstolic, Jennifer L.; Hayes, Donald C.; Ruhl, Peter M.

    2006-01-01

    Increasing development and increasing water withdrawals for public, industrial, and agricultural water supply threaten to reduce streamflows in the Shenandoah River basin in Virginia. Water managers need more information to balance human water-supply needs with the daily streamflows necessary for maintaining the aquatic ecosystems. To meet the need for comprehensive information on hydrology, water supply, and instream-flow requirements of the Shenandoah River basin, the U.S. Geological Survey and the Northern Shenandoah Valley Regional Commission conducted a cooperative investigation of habitat availability during low-flow periods on the North Fork Shenandoah River. Historic streamflow data and empirical data on physical habitat, river hydraulics, fish community structure, and recreation were used to develop a physical habitat simulation model. Hydraulic measurements were made during low, medium, and high flows in six reaches at a total of 36 transects that included riffles, runs, and pools, and that had a variety of substrates and cover types. Habitat suitability criteria for fish were developed from detailed fish-community sampling and microhabitat observations. Fish were grouped into four guilds of species and life stages with similar habitat requirements. Simulated habitat was considered in the context of seasonal flow regimes to show the availability of flows that sustain suitable habitat during months when precipitation and streamflow are scarce. The North Fork Shenandoah River basin was divided into three management sections for analysis purposes: the upper section, middle section, and lower section. The months of July, August, and September were chosen to represent a low-flow period in the basin with low mean monthly flows, low precipitation, high temperatures, and high water withdrawals. Exceedance flows calculated from the combined data from these three months describe low-flow periods on the North Fork Shenandoah River. Long-term records from three

  6. Characteristics of extracellular polymeric substances of phototrophic biofilms at different aquatic habitats.

    Science.gov (United States)

    Fang, Fang; Lu, Wen-Tao; Shan, Qi; Cao, Jia-Shun

    2014-06-15

    Three different phototrophic biofilms obtained from a natural lake (Sample 1), drinking water plant (Sample 2) and wastewater treatment plant (Sample 3) were investigated. Diatoms and green algae were the dominant algae of three biofilms, and the biomass was highest in biofilm of Sample 2. The three phototrophic biofilms also had variable extracellular polymeric substances (EPS) concentrations and compositions. Total EPS concentration of 14.80 mg/g DW was highest in biofilm of Sample 2, followed by biofilms of Samples 3 and 1 (13.11 and 12.29 mg/g DW). Tightly bound EPS (TB-EPS) were the main fraction, and polysaccharides and protein were the main components of total EPS in all three biofilms. However, the compositions of loosely bound EPS (LB-EPS) and TB-EPS were different in three biofilms. Fourier-transform infrared and fluorescence spectra indicated different structure and compositions of LB-EPS and TB-EPS. These results demonstrated the characteristics of EPS produced by phototrophic biofilms varied and had compact relation to their growth environmental conditions.

  7. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  8. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  9. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  10. Impacts of surface water diversions for marijuana cultivation on aquatic habitat in four northwestern California watersheds.

    Directory of Open Access Journals (Sweden)

    Scott Bauer

    Full Text Available Marijuana (Cannabis sativa L. cultivation has proliferated in northwestern California since at least the mid-1990s. The environmental impacts associated with marijuana cultivation appear substantial, yet have been difficult to quantify, in part because cultivation is clandestine and often occurs on private property. To evaluate the impacts of water diversions at a watershed scale, we interpreted high-resolution aerial imagery to estimate the number of marijuana plants being cultivated in four watersheds in northwestern California, USA. Low-altitude aircraft flights and search warrants executed with law enforcement at cultivation sites in the region helped to validate assumptions used in aerial imagery interpretation. We estimated the water demand of marijuana irrigation and the potential effects water diversions could have on stream flow in the study watersheds. Our results indicate that water demand for marijuana cultivation has the potential to divert substantial portions of streamflow in the study watersheds, with an estimated flow reduction of up to 23% of the annual seven-day low flow in the least impacted of the study watersheds. Estimates from the other study watersheds indicate that water demand for marijuana cultivation exceeds streamflow during the low-flow period. In the most impacted study watersheds, diminished streamflow is likely to have lethal or sub-lethal effects on state- and federally-listed salmon and steelhead trout and to cause further decline of sensitive amphibian species.

  11. Hydrological Regimes, Pond Morphology, and Habitat Use: Predicting the Impact of an Emerging Aquatic Pathogen

    OpenAIRE

    Cheryl J Briggs

    2006-01-01

    Declines in amphibian populations have been reported throughout the world in recent years. Chytridiomycosis, a disease of amphibians caused by the chytrid fungus, Batrachochytrium dendrobatidis, is one of a number of factors that have been shown to contribute to these population declines. B. dendrobatidis is associated with rapid population declines and local extinctions of populations of mountain yellow-legged frog, Rana muscosa, in some areas of the California Sierra Nevada mountains, howev...

  12. Habitat associations of fish and aquatic turtles in an East Texas Stream

    Directory of Open Access Journals (Sweden)

    Riedle J.D.

    2016-01-01

    Full Text Available The community structure of stream communities are treated as bioassays of stream ecosystems and changes to species patterns within those communities reflect response to multiple stressors including natural fluctuations in environmental variables. Research has focused on the structure of fish assemblages and there is increasing interest in environmental factors structuring turtle communities. Both fishes and turtles can be sampled using common methods, but are rarely studied together. Our objective was to compare distribution of fish and turtle species based on measured environmental variables in East Texas, USA. Species distributions were influenced by flow, substrate, and emergent vegetation. Results from Monte Carlo permutation tests suggest that downed woody debris and water temperature also had a strong influence on species distributions. Co-correspondence analysis showed considerable overlap of species scores in the absence of environmental variables. The five macrohabitats sampled exhibited varying degrees of connectivity and thus species mixing, which is driven by annual fluctuations in precipitation. Results from this study suggest that turtles and fishes can be considered simultaneously and exhibit similar patterns of species distribution across the landscape, at least at local scales.

  13. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  14. Habitat-specific foraging of prothonotary warblers: Deducing habitat quality

    Science.gov (United States)

    Lyons, J.E.

    2005-01-01

    Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.

  15. Successional colonization of temporary streams: An experimental approach using aquatic insects

    Science.gov (United States)

    Godoy, Bruno Spacek; Queiroz, Luciano Lopes; Lodi, Sara; Nascimento de Jesus, Jhonathan Diego; Oliveira, Leandro Gonçalves

    2016-11-01

    The metacommunity concept studies the processes that structure communities on local and regional scales. This concept is useful to assess spatial variability. However, temporal patterns (e.g., ecological succession and colonization) are neglected in metacommunity studies, since such patterns require temporally extensive, and hard to execute studies. We used experimental habitats in temporary streams located within the Brazilian Cerrado to evaluate the importance of succession for the aquatic insect metacommunity. Five artificial habitats consisting of wrapped crushed rock were set transversally to the water flow in five streams. The habitats were sampled weekly to assess community composition, and replaced after sampling to identify new potential colonizers. We analyzed the accumulation of new colonizers after each week using a logistic model. We selected pairs of experimental habitats and estimated the Bray-Curtis dissimilarity index to assess the community composition trajectory during the experiment. We used the dissimilarity values in ANOVA tests, identifying the importance of time and space for the community. The number of new taxa stabilized in the third week, and we estimated a weekly increase of 1.61 new taxa in the community after stabilization. The overall pattern was a small change on community composition, but one stream had a higher weekly turnover. Our results showed a relevant influence of time in the initial communities of aquatic insects of temporary streams. However, we must observe the temporal pattern in a spatial context, once different streams have different successional history regarding number of taxa and community turnover. We highlight the importance of aerial dispersal and movement to seek oviposition sites as an important factor in determining colonization patterns.

  16. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    Science.gov (United States)

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit; Clayton, John S.; Brix, Hans; Sorrell, Brian K.

    2010-01-01

    Background and Aims The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Methods Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. Key Results For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. Conclusions The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained

  17. The long-term impact of urbanisation on aquatic plants: Cambridge and the River Cam.

    Science.gov (United States)

    Preston, C D; Sheail, J; Armitage, P; Davy-Bowker, J

    2003-10-01

    Historical and contemporary records have been used to assess the impact of urbanisation on the aquatic plants of the River Cam and its narrow floodplain in Cambridge. Of the 62 native aquatic plant species which have been recorded in the study area since 1660, 40 (65%) were still present in the period 1985-1999 whereas 22 (35%) are apparently extinct. There is a striking relationship between the fate of species and their trophic requirements, with species of less eutrophic habitats having suffered disproportionately. Historical records demonstrate that the River Cam became grossly polluted by sewage from Cambridge in the 19th century, but the chemical and biological quality of the river improved from 1897 onwards. However, the majority of the species recorded from the river and nearby ditches persisted until after maximum incidence of sewage pollution, which may even have stimulated the growth of 'weed' in the river. Losses of aquatic plant species from two riparian commons, Coe Fen (35%) and Sheep's Green (50%), have been particularly great. The level of these and other areas of low-lying common land by the river has been systematically raised by the controlled tipping of waste in hollows, followed by levelling and resowing. The main effects of urbanisation on the flora therefore arose from the transformation of riparian pastures into suburban open spaces. Commons which are used purely for amenity purposes have lost almost all their aquatic plant species. Those which are still grazed retain more, and continuance of grazing is probably essential if a varied aquatic flora is to be maintained. The interpretation of botanical records in terms of recorded management history is likely to throw further light on the processes of urbanisation, although the number of sites with a sufficiently detailed botanical record may be limited. PMID:14499527

  18. Naragh Suburb, Center of Iran; A Natural Habitat of Hirudo medicinalis

    Directory of Open Access Journals (Sweden)

    Dehghani R.1 PhD,

    2014-08-01

    Full Text Available Aims A very common species of leeches has been named as Hirudo medicinalis. Regarding to the application of leeches in medicine and their fast extinction, this study was performed in aquatic habitats of Kashan aimed to determine the distribution of leeches and to provide information about their regional and habitat characteristics. Materials & Methods This descriptive study was conducted during 2008 to 2010 in three periods and 90 samples from 30 sites were collected, totally. 30 lentic and lotic aquatic habitats located in different regions of Naragh were recognized and selected. Leeches were collected initially in 10% ethanol followed by washing and removing mucus and then maintained in 70% ethanol. The identification keys were used for recognizing the species of leeches. Findings According to the identification key of the leech species, 15 samples from the total samples of 30 locations were Hirudo medicinalis. Total Hirudo medicinalis samples were collected just from Naragh River. These species of leeches were relatively large with 7-10cm and their colors were olive green, brown and greenish brown with a red stripe on the sides. Conclusion Naragh River is one of the habitats of Hirudo medicinalis.

  19. Autonomous Systems: Habitat Automation Element

    Data.gov (United States)

    National Aeronautics and Space Administration — We define a habitat fairly broadly to include any enclosed space that is intended to house people for an extended period of time away from the Earth....

  20. Waterfowl Production and Habitat Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Waterfowl Production and Habitat Survey, conducted by the U.S. Fish and Wildlife Service, became operational in 1955 in the Canadian prairies (strata 26-40). In...

  1. Leatherback Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for leatherback turtle as designated by Federal Register Vol. 44, No. 17711, March 23, 1979, Rules and Regulations....

  2. Hawksbill Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for hawksbill turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations....

  3. Tidal Creek Sentinel Habitat Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ecological Research, Assessment and Prediction's Tidal Creeks: Sentinel Habitat Database was developed to support the National Oceanic and Atmospheric...

  4. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  5. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  6. Habitat--Offshore Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Monterey map area, California. The vector data file is included in...

  7. Shrub-Scrub Habitat Evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Conversion of the current shrub-scrub habitats west of Sandpiper Road and north of the Back BayNational Wildlife Refuge, into recreational facilities for a new...

  8. An analysis of diet quality, how it controls fatty acid profiles, isotope signatures and stoichiometry in the malaria mosquito Anopheles arabiensis.

    Directory of Open Access Journals (Sweden)

    Rebecca Hood-Nowotny

    Full Text Available BACKGROUND: Knowing the underlying mechanisms of mosquito ecology will ensure effective vector management and contribute to the overall goal of malaria control. Mosquito populations show a high degree of population plasticity in response to environmental variability. However, the principle factors controlling population size and fecundity are for the most part unknown. Larval habitat and diet play a crucial role in subsequent mosquito fitness. Developing the most competitive insects for sterile insect technique programmes requires a "production" orientated perspective, to deduce the most effective larval diet formulation; the information gained from this process offers us some insight into the mechanisms and processes taking place in natural native mosquito habitats. METHODOLOGY/PRINCIPAL FINDINGS: Fatty acid profiles and de-novo or direct assimilation pathways, of whole-individual mosquitoes reared on a range of larval diets were determined using pyrolysis gas chromatograph/mass spectrometry. We used elemental analysis and isotope ratio mass spectrometry to measure individual-whole-body carbon, nitrogen and phosphorous values and to assess the impact of dietary quality on subsequent population stoichiometry, size, quality and isotopic signature. Diet had the greatest impact on fatty acid (FA profiles of the mosquitoes, which exhibited a high degree of dietary routing, characteristic of generalist feeders. De-novo synthesis of a number of important FAs was observed. Mosquito C:N stoichiometry was fixed in the teneral stage. Dietary N content had significant influence on mosquito size, and P was shown to be a flexible pool which limited overall population size. CONCLUSIONS/SIGNIFICANCE: Direct routing of FAs was evident but there was ubiquitous de-novo synthesis suggesting mosquito larvae are competent generalist feeders capable of survival on diet with varying characteristics. It was concluded that nitrogen availability in the larval diet

  9. Arbuscular Mycorrhizal and Dark Septate Endophyte Fungal Associations in South Indian Aquatic and Wetland Macrophytes

    Directory of Open Access Journals (Sweden)

    Kumar Seerangan

    2014-01-01

    Full Text Available Investigations on the prevalence of arbuscular mycorrhizal (AM and dark septate endophyte (DSE fungal symbioses are limited for plants growing in tropical aquatic and wetland habitats compared to those growing on terrestrial moist or dry habitats. Therefore, we assessed the incidence of AM and DSE symbiosis in 8 hydrophytes and 50 wetland plants from four sites in south India. Of the 58 plant species examined, we found AM and DSE fungal symbiosis in 21 and five species, respectively. We reported for the first time AM and DSE fungal symbiosis in seven and five species, respectively. Intermediate-type AM morphology was common, and AM morphology is reported for the first time in 16 plant species. Both AM and DSE fungal colonization varied significantly across plant species and sites. Intact and identifiable AM fungal spores occurred in root zones of nine plant species, but AM fungal species richness was low. Though no clear relationship between AM and DSE fungal colonization was recognized, a significant negative correlation between AM colonization and spore numbers was established. Our study suggests that the occurrence of AM and DSE fungal symbiosis in plants growing in hydrophytic and wetland habitats is not as common as in terrestrial habitats.

  10. Habitat classification modeling with incomplete data: pushing the habitat envelope.

    Science.gov (United States)

    Zarnetske, Phoebe L; Edwards, Thomas C; Moisen, Gretchen G

    2007-09-01

    Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical techniques for HCMs. One option is to generate pseudo-absence points so that the many available statistical modeling tools can bb used. Traditional techniques generate pseudo-absence points at random across broadly defined species ranges, often failing to include biological knowledge concerning the species-habitat relationship. We incorporated biological knowledge of the species-habitat relationship into pseudo-absence points by creating habitat envelopes that constrain the region from which points were randomly selected. We define a habitat envelope as an ecological representation of a species, or species feature's (e.g., nest) observed distribution (i.e., realized niche) based on a single attribute, or the spatial intersection of multiple attributes. We created HCMs for Northern Goshawk (Accipiter gentilis atricapillus) nest habitat during the breeding season across Utah forests with extant nest presence points and ecologically based pseudo-absence points using logistic regression. Predictor variables were derived from 30-m USDA Landfire and 250-m Forest Inventory and Analysis (FIA) map products. These habitat-envelope-based models were then compared to null envelope models which use traditional practices for generating pseudo-absences. Models were assessed for fit and predictive capability using metrics such as kappa, threshold-independent receiver operating characteristic (ROC) plots, adjusted deviance (D(adj)2), and cross-validation, and were also assessed for ecological relevance. For all cases, habitat envelope-based models outperformed null envelope models and were more ecologically relevant

  11. Developing a novel approach to analyse the regimes of temporary streams and their controls on aquatic biota

    Directory of Open Access Journals (Sweden)

    F. Gallart

    2011-10-01

    Full Text Available Temporary streams are those water courses that undergo the recurrent cessation of flow or the complete drying of their channel. The biological communities in temporary stream reaches are strongly dependent on the temporal changes of the aquatic habitats determined by the hydrological conditions. The use of the aquatic fauna structural and functional characteristics to assess the ecological quality of a temporary stream reach can not therefore be made without taking into account the controls imposed by the hydrological regime. This paper develops some methods for analysing temporary streams' aquatic regimes, based on the definition of six aquatic states that summarize the sets of mesohabitats occurring on a given reach at a particular moment, depending on the hydrological conditions: flood, riffles, connected, pools, dry and arid. We used the water discharge records from gauging stations or simulations using rainfall-runoff models to infer the temporal patterns of occurrence of these states using the developed aquatic states frequency graph. The visual analysis of this graph is complemented by the development of two metrics based on the permanence of flow and the seasonal predictability of zero flow periods. Finally, a classification of the aquatic regimes of temporary streams in terms of their influence over the development of aquatic life is put forward, defining Permanent, Temporary-pools, Temporary-dry and Episodic regime types. All these methods were tested with data from eight temporary streams around the Mediterranean from MIRAGE project and its application was a precondition to assess the ecological quality of these streams using the current methods prescribed in the European Water Framework Directive for macroinvertebrate communities.

  12. Habitat change influences mate search behaviour in three-spined sticklebacks

    DEFF Research Database (Denmark)

    Heuschele, Jan; Salminen, Tiina; Candolin, Ulrika

    2012-01-01

    Mate choice is one of the main mechanisms of sexual selection, with profound implications for individual fitness. Changes in environmental conditions can cause individuals to alter their mate search behaviour, with consequences for mate choice. Human-induced eutrophication of water bodies...... evaluation in the absence of visual stimulation. This reduced the rate of mate encounters and probably also the opportunity for choice. Our results show that changes in habitat structure and visibility can alter female mate searching, with potential consequences for the opportunity for sexual selection....... is a global problem that alters habitat structure and visibility in aquatic ecosystems. We investigated whether changes in habitat complexity and male cue modality, visual or olfactory, influence mate search behaviour of female three-spined sticklebacks, Gasterosteus aculeatus. We allowed gravid females...

  13. Remote sensing and GIS [geographic information system] technology for wildlife habitat assessment

    International Nuclear Information System (INIS)

    A geographic information system (GIS) data base was prepared for 217 square kilometers of the Savannah River Plant (SRP). Since 1952, these facilities have released once-through cooling water into several streams and lakes which eventually discharge into the Savannah River. The thermal effluents have altered wetland vegetation along the stream channel floodplains and in the SRP portion of the Savannah River swamp. Two large cooling reservoirs were constructed to reduce these effects. Terrestrial and aquatic wildlife habitat studies were conducted as part of the Final Environmental Impact Statement prepared for several cooling system alternatives. This paper addresses the use of a GIS data base and other remote sensing data in support of habitat assessments for these alternatives using the US Fish and Wildlife Service Habitat Evaluation Procedures. 9 refs

  14. Asotin Creek Instream Habitat Alteration Projects: 1998 Habitat Evaluation Surveys.

    Energy Technology Data Exchange (ETDEWEB)

    Bumgarner, Joseph D.

    1999-03-01

    The Asotin Creek Model Watershed Master Plan was completed 1994. The plan was developed by a landowner steering committee for the Asotin County Conservation District (ACCD), with technical support from the various Federal, State and local entities. Actions identified within the plan to improve the Asotin Creek ecosystem fall into four main categories, (1) Stream and Riparian, (2) Forestland, (3) Rangeland, and (4) Cropland. Specific actions to be carried out within the stream and in the riparian area to improve fish habitat were, (a) create more pools, (b) increase the amount of large organic debris (LOD), (c) increase the riparian buffer zone through tree planting, and (d) increase fencing to limit livestock access; additionally, the actions are intended to stabilize the river channel, reduce sediment input, and protect private property. Fish species of main concern in Asotin Creek are summer steelhead (Oncorhynchus mykiss), spring chinook (Oncorhynchus tshawytscha), and bull trout (Salvelinus confluentus). Spring chinook in Asotin Creek are considered extinct (Bumgarner et al. 1998); bull trout and summer steelhead are below historical levels and are currently as ''threatened'' under the ESA. In 1998, 16 instream habitat projects were planned by ACCD along with local landowners. The ACCD identified the need for a more detailed analysis of these instream projects to fully evaluate their effectiveness at improving fish habitat. The Washington Department of Fish and Wildlife's (WDFW) Snake River Lab (SRL) was contracted by the ACCD to take pre-construction measurements of the existing habitat (pools, LOD, width, depth, etc.) within each identified site, and to eventually evaluate fish use within these sites. All pre-construction habitat measurements were completed between 6 and 14 July, 1998. 1998 was the first year that this sort of evaluation has occurred. Post construction measurements of habitat structures installed in 1998, and fish

  15. Nutrition, illness, and injury in aquatic sports.

    Science.gov (United States)

    Pyne, David B; Verhagen, Evert A; Mountjoy, Margo

    2014-08-01

    In this review, we outline key principles for prevention of injury and illness in aquatic sports, detail the epidemiology of injury and illness in aquatic athletes at major international competitions and in training, and examine the relevant scientific evidence on nutrients for reducing the risk of illness and injury. Aquatic athletes are encouraged to consume a well-planned diet with sufficient calories, macronutrients (particularly carbohydrate and protein), and micronutrients (particularly iron, zinc, and vitamins A, D, E, B6, and B12) to maintain health and performance. Ingesting carbohydrate via sports drinks, gels, or sports foods during prolonged training sessions is beneficial in maintaining energy availability. Studies of foods or supplements containing plant polyphenols and selected strains of probiotic species are promising, but further research is required. In terms of injury, intake of vitamin D, protein, and total caloric intake, in combination with treatment and resistance training, promotes recovery back to full health and training. PMID:24937101

  16. Nutrition, illness, and injury in aquatic sports.

    Science.gov (United States)

    Pyne, David B; Verhagen, Evert A; Mountjoy, Margo

    2014-08-01

    In this review, we outline key principles for prevention of injury and illness in aquatic sports, detail the epidemiology of injury and illness in aquatic athletes at major international competitions and in training, and examine the relevant scientific evidence on nutrients for reducing the risk of illness and injury. Aquatic athletes are encouraged to consume a well-planned diet with sufficient calories, macronutrients (particularly carbohydrate and protein), and micronutrients (particularly iron, zinc, and vitamins A, D, E, B6, and B12) to maintain health and performance. Ingesting carbohydrate via sports drinks, gels, or sports foods during prolonged training sessions is beneficial in maintaining energy availability. Studies of foods or supplements containing plant polyphenols and selected strains of probiotic species are promising, but further research is required. In terms of injury, intake of vitamin D, protein, and total caloric intake, in combination with treatment and resistance training, promotes recovery back to full health and training.

  17. Emergent aquatic plants: biological and economic perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Kresovich, S.; Wagner, C.K.; Scantland, D.A.; Lawhon, W.T.

    1981-01-01

    One of the most productive, but least exploited, biomass resources is the group classified as the emergent aquatic plants. Information is presented concerning the biological and economic factors that must be considered if emergent aquatic plants are to become viable feedstocks for multipurpose systems. The feedstock purposes highlighted include fuel and/or chemical production and the species identified as potential candidates for production in biomass systems include Arundo donax, Cyperus papyrus, Phragmites communis, Saccharum spontaneum, Spartina alterniflora, and Typha latifolla. If these species are to be viable candidates in biomass systems, a number of research areas must be investigated further. Issues such as the development of base-line yield data for managed systems, mechanization and harvesting conceptualization, genetic (crop) improvement, identification of secondary plant products, and economic considerations require refinement. However, the potential pay-off for developing emergent aquatic systems will be significant if successful. 19 references.

  18. Persistence at distributional edges: Columbia spotted frog habitat in the arid Great Basin, USA.

    Science.gov (United States)

    Arkle, Robert S; Pilliod, David S

    2015-09-01

    A common challenge in the conservation of broadly distributed, yet imperiled species is understanding which factors facilitate persistence at distributional edges, locations where populations are often vulnerable to extirpation due to changes in climate, land use, or distributions of other species. For Columbia spotted frogs (Rana luteiventris) in the Great Basin (USA), a genetically distinct population segment of conservation concern, we approached this problem by examining (1) landscape-scale habitat availability and distribution, (2) water body-scale habitat associations, and (3) resource management-identified threats to persistence. We found that areas with perennial aquatic habitat and suitable climate are extremely limited in the southern portion of the species' range. Within these suitable areas, native and non-native predators (trout and American bullfrogs [Lithobates catesbeianus]) are widespread and may further limit habitat availability in upper- and lower-elevation areas, respectively. At the water body scale, spotted frog occupancy was associated with deeper sites containing abundant emergent vegetation and nontrout fish species. Streams with American beaver (Castor canadensis) frequently had these structural characteristics and were significantly more likely to be occupied than ponds, lakes, streams without beaver, or streams with inactive beaver ponds, highlighting the importance of active manipulation of stream environments by beaver. Native and non-native trout reduced the likelihood of spotted frog occupancy, especially where emergent vegetation cover was sparse. Intensive livestock grazing, low aquatic connectivity, and ephemeral hydroperiods were also negatively associated with spotted frog occupancy. We conclude that persistence of this species at the arid end of its range has been largely facilitated by habitat stability (i.e., permanent hydroperiod), connectivity, predator-free refugia, and a commensalistic interaction with an ecosystem

  19. Quantifying the role of woody debris in providing bioenergetically favorable habitat for juvenile salmon

    Science.gov (United States)

    Harrison, L.; Hafs, A. W.; Utz, R.; Dunne, T.

    2013-12-01

    The habitat complexity of a riverine ecosystem substantially influences aquatic communities, and especially the bioenergetics of drift feeding fish. We coupled hydrodynamic and bioenergetic models to assess the influence of habitat complexity, generated via large woody debris (LWD) additions, on juvenile Chinook salmon (Oncorhynchus tshawytscha) growth potential in a river that lacked large wood. Model simulations indicated that LWD diversified the flow field, creating pronounced velocity gradients, which enhanced fish feeding and resting activities at the micro-habitat (sub-meter) scale. Fluid drag created by individual wood structures was increased under higher wood loading rates, leading to a 5-19% reduction in the reach-averaged velocity. We found that wood loading was asymptotically related to the reach-scale growth potential, suggesting that the river became saturated with LWD and additional loading would produce minimal benefit. In our study reach, LWD additions could potentially quadruple the potential growth area available before that limit was reached. Wood depletion in the world's rivers has been widely documented, leading to widespread attempts by river managers to reverse this trend by adding wood to simplified aquatic habitats, though systematic prediction of the effects of wood on fish growth has not been previously accomplished. We offer a quantitative, theory-based approach for assessing the role of wood on habitat potential as it affects fish growth at the micro-habitat and reach-scales. Fig. 1. Predicted flow field and salmon growth potential maps produced from model simulations with no woody debris (Graphs A and D), a low density (Graphs B and E), and a high density (Graphs C and E) of woody debris.

  20. Biodiversity of trematodes associated with amphibians from a variety of habitats in Corrientes Province, Argentina.

    Science.gov (United States)

    Hamann, M I; Kehr, A I; González, C E

    2013-09-01

    The main goals of this study were to compare the richness of parasitic trematodes in amphibians with diverse habits (terrestrial, fossorial, semi-aquatic and arboreal), and to evaluate whether the composition of the trematode community is determined by ecological relationships. Specimens were collected between April 2001 and December 2006 from a common area (30 ha) in Corrientes Province, Argentina. Trematodes of amphibians in this area comprised a total of 19 species, and were dominated by common species. Larval trematodes presented highest species richness, with the metacercaria of Bursotrema tetracotyloides being dominant in the majority (7/9, 78%) of the parasite communities. Adults of the trematode Catadiscus inopinatus were dominant in the majority (6/9, 67%) of amphibians. The amphibians Leptodactylus latinasus, Leptodactylus bufonius and Scinax nasicus presented a high diversity of trematodes, whereas Leptodactylus chaquensis had the lowest diversity even though it presented with the highest species richness. The patterns of similarity among amphibian species showed groups linking with their habitats. Leptodactilid amphibians, with a generalist diet and an active foraging strategy showed highest infection rates with adult trematodes. The mean richness of trematode species related to host's habitat preferences was higher in semi-aquatic amphibians. Results suggest that semi-aquatic amphibians, present in both aquatic and terrestrial environments, present a greater diversity of parasites as they have a higher rate of exposure to a wider range of prey species and, hence, to diverse infective states. The trematode composition is related to the diets and mobility of the host, and habitat.

  1. New North American records of aquatic insects as paratenic hosts of pheromermis (nematoda : mermithidae).

    Energy Technology Data Exchange (ETDEWEB)

    Molloy, D. P.; Vinikour, W. S.; Anderson, R. V.; Environmental Assessment; New York State Museum; Western Illinois Univ.

    1999-07-01

    Several species of aquatic insects in Trout Park Nature Preserve (Elgin, IL) were observed to have small, black spots (<0.1 mm diameter) visible within their bodies. Microscopic examination revealed these spots to be coiled juveniles of a mermithid (Nematoda: Mermithidae). Based on host habitat (seepage areas and rivulets), host species (aquatic insects), and size (mean diameter of coiled juveniles = 79 {mu}m), it is likely that these mermithids were in the genus Pheromermis. Since adult mermithids were not found, species determination was not feasible, and the possibility of a new species cannot be ruled out. Pheromermis pachysoma and Pheromermis vesparum, however, are two species known to use aquatic insects as paratenic (i.e., transport) hosts in order to reach their definitive hosts, vespid wasps. Wasp larvae are infected by consuming the flesh of adult aquatic insects that contain the coiled juveniles of these Pheromermis spp. Of the 19 macroinvertebrate species examined in this study, Pheromermis juveniles were found in 4 caddisfly species (Hesperophylax designatus, Lepidostoma liba, Glossosoma intermedium, and Diplectrona modesta) and in 2 stonefly species (Clioperla clio and Amphinemura delosa). In addition to all 6 insect species being new host records for Pheromermis infection, this also represents the first report of nematode infection in stoneflies within the Western Hemisphere and of a Pheromermis sp. in Illinois. Among trophic groups, insect detritivores have been frequently recorded infected with coiled Pheromermis juveniles because of their direct consumption of eggs, and we also observed this for detritivores in our investigation (e.g., L. liba and A. delosa). Because C. clio was intensively infected, however, our study also provided evidence that predatory insects can be paratenic hosts. Coiled juveniles were typically present in muscle and fat body and present in almost all body regions. Not every infected paratenic host had external signs of

  2. Effects of modifications of aquatic ecosystems

    International Nuclear Information System (INIS)

    Studies under this program historically have been concerned with the effects of a variety of stress factors on aquatic populations and communities. Current research was focused principally on ionizing radiation, and includes studies on the interaction of acute radiation and temperature on fish, the in situ measurement of radiation exposure in an aquatic environment, and the uptake and retention of tritium in a simulated pond community. In response to the expanded responsibilities of the recently formed Energy Research and Development Administration in dealing with all forms of energy related problems, this program will be redirected in the coming year to nonnuclear energy research

  3. Microbial ecology of Antarctic aquatic systems.

    Science.gov (United States)

    Cavicchioli, Ricardo

    2015-11-01

    The Earth's biosphere is dominated by cold environments, and the cold biosphere is dominated by microorganisms. Microorganisms in cold Southern Ocean waters are recognized for having crucial roles in global biogeochemical cycles, including carbon sequestration, whereas microorganisms in other Antarctic aquatic biomes are not as well understood. In this Review, I consider what has been learned about Antarctic aquatic microbial ecology from 'omic' studies. I assess the factors that shape the biogeography of Antarctic microorganisms, reflect on some of the unusual biogeochemical cycles that they are associated with and discuss the important roles that viruses have in controlling ecosystem function.

  4. Aquatic macroinvertebrates of the Jablanica river, Serbia

    Directory of Open Access Journals (Sweden)

    Stefanović Katarina S.

    2009-01-01

    Full Text Available Research on the community of aquatic macroinvertebrates was carried out during 2005 and 2006 at four sampling sites along the Jablanica River, a right-hand tributary of the Kolubara River. Fifty-seven taxa were recorded in the course of the investigation. The most diverse group was Ephemeroptera, followed by Trichoptera and Plecoptera. Members of the Rhitrogena semicolorata group were the most abundant. Our results could be the basis for evaluation of the influence of damming of the Jablanica River on the status of its water and can serve as a model for studying the influ­ence of hydromorphological degradation of aquatic ecosystems.

  5. Aquatic ape theory and fossil hominids.

    Science.gov (United States)

    Verhaegen, M J

    1991-06-01

    While most older palaeo-anthropological studies emphasise the similarities of the fossil hominids with modern man, recent studies often stress the unique and the apelike features of the australopithecine dentitions, skulls and postcranial bones. It is worth reconsidering the features of Australopithecus, Homo erectus and Homo neanderthalensis in the light of the so-called Aquatic Ape Theory (AAT) of Hardy and Morgan, and to compare the skeletal parts of our fossil relatives with those of (semi)aquatic animals. Possible convergences are observed with proboscis monkeys, beavers, sea-otters, hippopotamuses, seals, sea-lions, walruses, sea-cows, whales, dolphins, porpoises, penguins and crocodiles. PMID:1909768

  6. Radioactive contamination of aquatic media and organisms

    International Nuclear Information System (INIS)

    After a brief account of the radioactive wastes produced by peaceful or military uses of Atomic Industry, the author first describes a series of observations carried out 'in the field' on the extent of contamination in aquatic organisms with respect to that of the medium. The experimental studies are then analysed, with reference both to the radioisotope metabolism and to the factors and types of contamination of aquatic organisms by wastes from atomic industry. A precise experimental project is presented at the end of the paper, including almost 300 references. (author)

  7. National Training Center Fort Irwin expansion area aquatic resources survey

    Energy Technology Data Exchange (ETDEWEB)

    Cushing, C.E.; Mueller, R.P.

    1996-02-01

    Biologists from Pacific Northwest National Laboratory (PNNL) were requested by personnel from Fort Irwin to conduct a biological reconnaissance of the Avawatz Mountains northeast of Fort Irwin, an area for proposed expansion of the Fort. Surveys of vegetation, small mammals, birds, reptiles, amphibians, and aquatic resources were conducted during 1995 to characterize the populations and habitats present with emphasis on determining the presence of any species of special concern. This report presents a description of the sites sampled, a list of the organisms found and identified, and a discussion of relative abundance. Taxonomic identifications were done to the lowest level possible commensurate with determining the status of the taxa relative to its possible listing as a threatened, endangered, or candidate species. Consultation with taxonomic experts was undertaken for the Coleoptera ahd Hemiptera. In addition to listing the macroinvertebrates found, the authors also present a discussion related to the possible presence of any threatened or endangered species or species of concern found in Sheep Creek Springs, Tin Cabin Springs, and the Amargosa River.

  8. Comparison of aquatic macroinvertebrate samples collected using different field methods

    Science.gov (United States)

    Lenz, Bernard N.; Miller, Michael A.

    1996-01-01

    Government agencies, academic institutions, and volunteer monitoring groups in the State of Wisconsin collect aquatic macroinvertebrate data to assess water quality. Sampling methods differ among agencies, reflecting the differences in the sampling objectives of each agency. Lack of infor- mation about data comparability impedes data shar- ing among agencies, which can result in duplicated sampling efforts or the underutilization of avail- able information. To address these concerns, com- parisons were made of macroinvertebrate samples collected from wadeable streams in Wisconsin by personnel from the U.S. Geological Survey- National Water Quality Assessment Program (USGS-NAWQA), the Wisconsin Department of Natural Resources (WDNR), the U.S. Department of Agriculture-Forest Service (USDA-FS), and volunteers from the Water Action Volunteer-Water Quality Monitoring Program (WAV). This project was part of the Intergovernmental Task Force on Monitoring Water Quality (ITFM) Wisconsin Water Resources Coordination Project. The numbers, types, and environmental tolerances of the organ- isms collected were analyzed to determine if the four different field methods that were used by the different agencies and volunteer groups provide comparable results. Additionally, this study com- pared the results of samples taken from different locations and habitats within the same streams.

  9. 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

  10. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    A. KUN

    2007-01-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  11. Habitat Suitability Index Models: Bigmouth Buffalo

    Science.gov (United States)

    Edwards, Elizabeth A.

    1983-01-01

    A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for Bigmouth buffalo (Ictiobus cyprinellus), a freshwater fish. The models are scaled to produce an indices of habitat suitability between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for freshwater areas of the continental United States. Other habitat suitability models found in the literature are also included. Habitat suitability indices (HSI's) are designed for use with the habitat evaluation procedures developed by the U.S. Fish and Wildlife Service.

  12. Assessment of Habitat and Streamflow Requirements for Habitat Protection, Usquepaug-Queen River, Rhode Island, 1999-2000

    Science.gov (United States)

    Armstrong, David S.; Parker, Gene W.

    2003-01-01

    The relations among stream habitat and hydrologic conditions were investigated in the Usquepaug?Queen River Basin in southern Rhode Island. Habitats were assessed at 13 sites on the mainstem and tributaries from July 1999 to September 2000. Channel types are predominantly low-gradient glides, pools, and runs that have a sand and gravel streambed and a forest or shrub riparian zone. Along the stream margins,overhanging brush, undercut banks supported by roots, and downed trees create cover; within the channel, submerged aquatic vegetation and woody debris create cover. These habitat features decrease in quality and availability with declining streamflows, and features along stream margins generally become unavailable once streamflows drop to the point at which water recedes from the stream banks. Riffles are less common, but were identified as critical habitat areas because they are among the first to exhibit habitat losses or become unavailable during low-flow periods. Stream-temperature data were collected at eight sites during summer 2000 to indicate the suitability of those reaches for cold-water fish communities. Data indicate stream temperatures provide suitable habitat for cold-water species in the Fisherville and Locke Brook tributaries and in the mainstem Queen River downstream of the confluence with Fisherville Brook. Stream temperatures in the Usquepaug River downstream from Glen Rock Reservoir are about 6?F warmer than in the Queen River upstream from the impoundment. These warmer temperatures may make habitat in the Usquepaug River marginal for cold-water species. Fish-community composition was determined from samples collected at seven sites on tributaries and at three sites on the mainstem Usquepaug?Queen River. Classification of the fish into habitat-use groups and comparison to target fish communities developed for the Quinebaug and Ipswich Rivers indicated that the sampled reaches of the Usquepaug?Queen River contained most of the riverine fish

  13. Dinoflagelados em diversos habitats e hidroperíodos na zona costeira do sul do Brasil Dinoflagellates in different habitats and hydroperiods on the coast of southern Brazil

    Directory of Open Access Journals (Sweden)

    Luciana de Souza Cardoso

    2007-06-01

    Full Text Available Informações sobre a riqueza, densidade, diversidade e distribuição de dinoflagelados em habitats aquáticos (lagoas abertas e fechadas, canais, açudes e áreas úmidas, em relação aos períodos de águas altas e baixas, são apresentadas. O estudo baseou-se em amostragens realizadas em 23 pontos, localizados nas margens leste (área da Lagoa do Casamento e oeste (área do Butiazal de Tapes da laguna dos Patos, no ano de 2003. Foram identificados 11 táxons, cuja distribuição teve maior homogeneidade no período de águas altas. Durinskia baltica (Levander Carty & Cox foi o único táxon cuja distribuição não se alterou pelo hidroperíodo. Peridinium gatunense Nygaard foi uma espécie indicadora de águas altas e P. umbonatum Stein foi indicadora de habitats associados à área do Butiazal de Tapes. Esta área mostrou ter mais alta diversidade de Dinophyceae em relação à área da Lagoa do Casamento, independente do hidroperíodo, refletindo a maior diversidade e especificidade de habitats aquáticos. O tipo de habitat influenciou significativamente (pData on richness, density, diversity and distribution of dinoflagellates in aquatic habitats (open and closed lagoons, channels, reservoirs and wetlands during high and low water periods are presented. The study was based on 23 point samples, located on the eastern (Lagoa do Casamento area and western (Butiazal de Tapes area shores of Laguna dos Patos, in 2003. Eleven taxa were identified; taxon distribution was more homogeneous during the high-water period. Durinskia baltica (Levander Carty & Cox was the only taxon whose distribution was the same for both hydroperiods. Peridinium gatunense Nygaard was a high-water indicator species and P. umbonatum Stein was an indicator of habitats associated with the Butiazal de Tapes area. This area had higher Dinophyceae diversity than the Lagoa do Casamento area, regardless of hydroperiod, due to the higher diversity and specificity of aquatic

  14. Characteristics of terrestrial and aquatic ecosystems of two locations in Deaf Smith and Swisher Counties, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1984-11-01

    According to the Civilian Radioactive Waste Management Program and the Nuclear Waste Policy Act of 1982 (P.L. 97-425), a potential nuclear waste repository site must be chosen with consideration of potential impacts on terrestrial and aquatic ecosystems. This report is a preliminary environmental characterization of two locations in the Texas Panhandle, one in Deaf Smith County and the other in Swisher County, that have been recommended for further study. A description of important natural areas is offered as a basis for comparative studies of the two locations and for the identification and screening of potential repository sites. Information on current land uses, potential habitats, and expected plant and wildlife species is provided to assist field investigators in the collection of baseline data in support of further siting activities. The results of limited field surveys are also included. The report is in two parts. Part I contains a characterization of terrestrial ecological resources based upon limited field surveys aimed at verifying the presence of plant communities and wildlife habitats. It also presents inventories of species with special status, species with recreational and economic importance, and species of ecological value to important or special-status species. Part II presents information on aquatic ecosystems and resources derived primarily from a review of the literature, interviews, and limited field surveys. 21 figures, 18 tables.

  15. Characteristics of terrestrial and aquatic ecosystems of two locations in Deaf Smith and Swisher Counties, Texas

    International Nuclear Information System (INIS)

    According to the Civilian Radioactive Waste Management Program and the Nuclear Waste Policy Act of 1982 (P.L. 97-425), a potential nuclear waste repository site must be chosen with consideration of potential impacts on terrestrial and aquatic ecosystems. This report is a preliminary environmental characterization of two locations in the Texas Panhandle, one in Deaf Smith County and the other in Swisher County, that have been recommended for further study. A description of important natural areas is offered as a basis for comparative studies of the two locations and for the identification and screening of potential repository sites. Information on current land uses, potential habitats, and expected plant and wildlife species is provided to assist field investigators in the collection of baseline data in support of further siting activities. The results of limited field surveys are also included. The report is in two parts. Part I contains a characterization of terrestrial ecological resources based upon limited field surveys aimed at verifying the presence of plant communities and wildlife habitats. It also presents inventories of species with special status, species with recreational and economic importance, and species of ecological value to important or special-status species. Part II presents information on aquatic ecosystems and resources derived primarily from a review of the literature, interviews, and limited field surveys. 21 figures, 18 tables

  16. Habitat requirements of Polygonetum natantis Soó 1927 and Potamogetonetum natantis Soó 1927 phytocenoses in north-eastern Poland

    Directory of Open Access Journals (Sweden)

    Stanisław Kłosowski

    2014-02-01

    Full Text Available Comparison of habitats of Polygonetum natantis Soó 1927 and Potamogetonetum natantis Soó 1927 phytocenoses as regards physical and chemical properties of the water and substrate demonstrated that the habitat requirements of both these communities are different. Polygonetum natantis phytocenoses indicate a substrate poor in nutrient components and rich waters, whereas Potamogetonetum natantis patches, on the contrary, are evidence of fertile substrate and waters poor in biophilous components. The differences in habitat conditions demonstrated between the examined communities confirm the correctness of narrow classification of aquatic plant communities, based on floristic dominance.

  17. Carp Control Techniques for Aquatic Plant Establishment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Over the years, fish and wildlife habitat in the Great Lakes basin has been dramatically altered by many factors including water level regulation, the introduction...

  18. Lower Clearwater Aquatic Mammal Survey. Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Mack, Curt; Kronemann, Loren A.; Eneas, Cheryl

    1994-08-01

    BPA provided funding to collect baseline data on river otters to assist in developing mitigation implementation plans for river otters percent to the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program, sections 1003 (b)(2) and (3). Distribution, movements, habitat use, and diets of river otters were investigated in the Clearwater River within the Nez Perce Indian Reservation from 1991-1992. The study outlined recommendations to guide development of mitigation implementation plans for riparian habitats. Sections of the Clearwater River were identified that if protected or enhanced would provide optimal benefit to otters. Habitat improvement alternatives were also outlined which could be used to enhance otter habitats.

  19. Habitat Suitability Index Models: Swamp Rabbit

    Science.gov (United States)

    Allen, Arthur W.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the swamp rabbit (Sylvilagus aquaticus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  20. Habitat Suitability Index Models: Eastern wild turkey

    Science.gov (United States)

    Schroeder, Richard L.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  1. Habitat Suitability Index Models: Smallmouth Buffalo

    Science.gov (United States)

    Edwards, Elizabeth A.; Twomey, Katie

    1982-01-01

    This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the Smallmouth buffalo (Ictiobus bubalus) are synthesized. These data are subsequently used to develop Habitat Suitability (HIS) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.

  2. Determining habitat quality for species that demonstrate dynamic habitat selection.

    Science.gov (United States)

    Beerens, James M; Frederick, Peter C; Noonburg, Erik G; Gawlik, Dale E

    2015-12-01

    Determining habitat quality for wildlife populations requires relating a species' habitat to its survival and reproduction. Within a season, species occurrence and density can be disconnected from measures of habitat quality when resources are highly seasonal, unpredictable over time, and patchy. Here we establish an explicit link among dynamic selection of changing resources, spatio-temporal species distributions, and fitness for predictive abundance and occurrence models that are used for short-term water management and long-term restoration planning. We used the wading bird distribution and evaluation models (WADEM) that estimate (1) daily changes in selection across resource gradients, (2) landscape abundance of flocks and individuals, (3) conspecific foraging aggregation, and (4) resource unit occurrence (at fixed 400 m cells) to quantify habitat quality and its consequences on reproduction for wetland indicator species. We linked maximum annual numbers of nests detected across the study area and nesting success of Great Egrets (Ardea alba), White Ibises (Eudocimus albus), and Wood Storks (Mycteria americana) over a 20-year period to estimated daily dynamics of food resources produced by WADEM over a 7490 km(2) area. For all species, increases in predicted species abundance in March and high abundance in April were strongly linked to breeding responses. Great Egret nesting effort and success were higher when birds also showed greater conspecific foraging aggregation. Synthesis and applications: This study provides the first empirical evidence that dynamic habitat selection processes and distributions of wading birds over environmental gradients are linked with reproductive measures over periods of decades. Further, predictor variables at a variety of temporal (daily-multiannual) resolutions and spatial (400 m to regional) scales effectively explained variation in ecological processes that change habitat quality. The process used here allows managers to

  3. Linking hydrologic, physical and chemical habitat environments for the potential assessment of fish community rehabilitation in a developing city

    Science.gov (United States)

    Zhao, C. S.; Yang, S. T.; Liu, C. M.; Dou, T. W.; Yang, Z. L.; Yang, Z. Y.; Liu, X. L.; Xiang, H.; Nie, S. Y.; Zhang, J. L.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.

    2015-04-01

    Aquatic ecological rehabilitation is increasingly attracting considerable public and research attention. An effective method that requires less data and expertise would help in the assessment of rehabilitation potential and in the monitoring of rehabilitation activities as complicated theories and excessive data requirements on assemblage information make many current assessment models expensive and limit their wide use. This paper presents an assessment model for restoration potential which successfully links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. In this model three newly developed sub-models, integrated habitat index (IHSI), integrated ecological niche breadth (INB) and integrated ecological niche overlap (INO), are established to study spatial heterogeneity of the restoration potential of fish assemblages based on gradient methods of habitat suitability index and ecological niche models. To reduce uncertainties in the model, as many fish species as possible, including important native fish, were selected as dominant species with monitoring occurring over several seasons to comprehensively select key habitat factors. Furthermore, a detrended correspondence analysis (DCA) was employed prior to a canonical correspondence analysis (CCA) of the data to avoid the "arc effect" in the selection of key habitat factors. Application of the model to data collected at Jinan City, China proved effective reveals that three lower potential regions that should be targeted in future aquatic ecosystem rehabilitation programs. They were well validated by the distribution of two habitat parameters: river width and transparency. River width positively influenced and transparency negatively influenced fish assemblages. The model can be applied for monitoring the effects of fish assemblage restoration

  4. Diversity and Impact of Prokaryotic Toxins on Aquatic Environments: A Review

    Directory of Open Access Journals (Sweden)

    Rogério Tenreiro

    2010-10-01

    Full Text Available Microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. Some of the most common toxins present in water are produced by several cyanobacterial species. As a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. Quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. These toxins are secondary metabolites, presenting a vast diversity of structures and variants. Most of cyanobacterial secondary metabolites are peptides or have peptidic substructures and are assumed to be synthesized by non-ribosomal peptide synthesis (NRPS, involving peptide synthetases, or NRPS/PKS, involving peptide synthetases and polyketide synthases hybrid pathways. Besides cyanobacteria, other bacteria associated with aquatic environments are recognized as significant toxin producers, representing important issues in food safety, public health, and human and animal well being. Vibrio species are one of the most representative groups of aquatic toxin producers, commonly associated with seafood-born infections. Some enterotoxins and hemolysins have been identified as fundamental for V. cholerae and V. vulnificus pathogenesis, but there is evidence for the existence of other potential toxins. Campylobacter spp. and Escherichia coli are also water contaminants and are able to produce important toxins after infecting their hosts. Other bacteria associated with aquatic environments are emerging as toxin producers, namely Legionella pneumophila and Aeromonas hydrophila, described as responsible for the synthesis of several exotoxins, enterotoxins and cytotoxins. Furthermore, several Clostridium species can produce potent neurotoxins. Although not considered aquatic microorganisms, they are ubiquitous in the environment and can easily contaminate drinking

  5. Systems and Cycles: Learning about Aquatic Ecosystems

    Science.gov (United States)

    Hmelo-Silver, Cindy E.; Jordan, Rebecca; Eberbach, Catherine; Rugaber, Spencer; Goel, Ashok

    2011-01-01

    In this research, the authors present both the design and preliminary testing of a technology-intensive classroom intervention designed to support middle schools students' understanding of an aquatic ecosystem. The goals of their intervention are to help learners develop deep understanding of ecosystems and to use tools that make the relationships…

  6. Aquatics Therapy and the Halliwick Concept

    Science.gov (United States)

    Skinner, Alison; Thomson, Ann

    2008-01-01

    Aquatic therapy is the use of the properties of water for the therapeutic benefit of people of all ages and abilities. This article illustrates how people with disabilities may maximize the benefits of activities in water, including individual and group work and swimming. The overall aim is to encourage family activity and social interaction. The…

  7. Aquatic ecotoxicity effect of engineered aminoclay nanoparticles

    DEFF Research Database (Denmark)

    Choi, Moon-Hee; Hwang, Yuhoon; Uk Lee, Hyun;

    2014-01-01

    In the present study the short term aquatic ecotoxicity of water-solubilized aminoclay nanoparticles (ANPs) of ~51±31 nm average hydrodynamic diameter was characterized. An ecotoxicological evaluation was carried out utilizing standard test organisms of different phyla and trophic levels namely t...

  8. Aquatic Pest Control. Sale Publication 4071.

    Science.gov (United States)

    Wamsley, Mary Ann, Ed.; Vermeire, Donna M., Ed.

    The information in this manual applies to control of aquatic pests in recreational waters, agricultural reservoirs, ornamental ponds, coastal bays, estuaries and channels, and drinking water reservoirs. Mechanical, cultural, biological, and chemical control methods are discussed. The majority of the material is devoted to weed control in static…

  9. Aquatic ecotoxicological indicators in life cycle assessment

    DEFF Research Database (Denmark)

    Pennington, David W.; Payet, Jerome; Hauschild, Michael Zwicky

    2004-01-01

    This paper compares available options for the aquatic ecotoxicological effect factor component in life cycle assessment (LCA). The effect factor is expressed here as the change in risk per unit change in cumulative exposure, ƒ´Effect/ƒ´Exposure. The comparison is restricted to approaches linked...

  10. SUBMERGED AQUATIC VEGETATION GARDENING MX974861

    Science.gov (United States)

    The Submerged Aquatic Vegetation Gardening project will acquire the seed/seedlings of SAVs for planting, will create an SAV gardening guide; and will create SAV plots at volunteers waterfront properties. Volunteers will gather data on plant size and spacing. Water quality test ...

  11. Black magic in the aquatic environment

    NARCIS (Netherlands)

    Jonker, M.T.O.

    2004-01-01

    Sorption to sediment controlsthe actual fate and risks ofhydrophobic organic contaminants (HOCs)in most aquatic environments. Sediment-bound HOCs are not readily available for uptake by organisms and degra

  12. Nano-plastics in the aquatic environment.

    Science.gov (United States)

    Mattsson, K; Hansson, L-A; Cedervall, T

    2015-10-01

    The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data. PMID:26337600

  13. Toxicokinetic modeling challenges for aquatic nanotoxicology

    Directory of Open Access Journals (Sweden)

    Wei-Yu eChen

    2016-01-01

    Full Text Available Nanotoxicity has become of increasing concern since the rapid development of metal nanoparticles (NPs. Aquatic nanotoxicity depends on crucial qualitative and quantitative properties of nanomaterials that induce adverse effects on subcellular, tissue, and organ level. The dose-response effects of size-dependent metal NPs, however, are not well investigated in aquatic organisms. In order to determine the uptake and elimination rate constants for metal NPs in the metabolically active/ detoxified pool of tissues, a one-compartmental toxicokinetic model can be applied when subcellular partitioning of metal NPs data would be available. The present review is an attempt to describe the nano-characteristics of toxicokinetics and subcellular partitioning on aquatic organisms with the help of the mechanistic modeling for NP size-dependent physiochemical properties and parameters. Physiologically-based pharmacokinetic (PBPK models can provide an effective tool to estimate the time course of NP accumulation in target organs and is useful in quantitative risk assessments. NP accumulation in fish should take into account different effects of different NP sizes to better understand tissue accumulative capacities and dynamics. The size-dependent NP partition coefficient is a crucial parameter that influences tissue accumulation levels in PBPK modeling. Further research is needed to construct the effective systems-level oriented toxicokinetic model that can provide a useful tool to develop quantitatively the robustly approximate relations that convey a better insight into the impacts of environmental metal NPs on subcellular and tissue/organ responses in aquatic organisms.

  14. Effects of radiation on aquatic organisms

    International Nuclear Information System (INIS)

    With the onset of nuclear age, nuclear fuel cycle products, nuclear medicine techniques, disposal of radio active wastes on land or in water, fall out of testing nuclear weapons has contributed large amount of radio nuclides to the water bodies. Radio nuclides can imbalance aquatic ecosystem resulting in danger to natural life. The biological effects of radiation on aquatic life are mortality, pathophysiological, reproductive, developmental and genetic changes. A broad review of the results obtained about the aquatic organisms related to different phyla indicates that the lower or less developed or more primitive organisms are more resistant than the higher or more advanced, developed and complex organisms to ionizing radiation. The algae, protozoa are more resistant than the insects, crustaceans, molluscs and fishes. The changes in sensitivity between different stages of development have also been noted. A review of the results of exposing salmonoid gametes, eggs, fingerlings and adults to X-rays supports the concepts that radio sensitivity decreases with age. This paper presents a selective review on effects of radiation and radio nuclides on the aquatic life. It include uses and sources of radiation, effective quantity of radiation, lethal and sub lethal effect, effects on survival, growth, reproduction, behaviour, metabolism, carcinogenicity and mutagenicity. (author)

  15. Landscape-stream interactions and habitat conservation for amphibians.

    Science.gov (United States)

    Ficetola, Gentile Francesco; Marziali, Laura; Rossaro, Bruno; De Bernardi, Fiorenza; Padoa-Schioppa, Emilio

    2011-06-01

    Semiaquatic organisms depend on the features of both water bodies and landscapes; the interplay between terrestrial and aquatic systems might influence the semiaquatic communities, determining the scale at which management would be more effective. However, the consequences of such interplay are not frequently quantified, particularly at the community level. We analyzed the distribution of amphibians to evaluate whether the influence of landscape features on freshwater ecosystems can have indirect consequences at both the species and community level. We surveyed 74 streams in northern Italy to obtain data on breeding amphibians, water, and microhabitat features; we also measured features of surrounding landscapes. We used an information-theoretic approach and structural equation models to compare hypotheses on causal relationships between species distribution and variables measured at multiple levels. We also used a constrained redundancy analyses to evaluate causal relationships between multivariate descriptors of habitat features and community composition. Distribution of Salamandra salamandra was related to landscape, hydrological, and water characteristics: salamanders were more frequent in permanent streams with low phosphate concentration within natural landscapes. Water characteristics were dependent on landscape: streams in natural landscapes had less phosphates. Landscape influenced the salamander both directly and indirectly through its influence on phosphates. Community structure was determined by both landscape and water characteristics. Several species were associated with natural landscapes, and with particular water characteristics. Landscape explained a significant proportion of variability of water characteristics; therefore it probably had indirect effects on community. Upland environments play key roles for amphibians, for example, as the habitat of adults, but upland environments also have indirect effects on the aquatic life stages, mediated

  16. Carryover aquatic effects on survival of metamorphic frogs during pond emigration

    Science.gov (United States)

    Chelgren, N.D.; Rosenberg, D.K.; Heppell, S.S.; Gitelman, A.I.

    2006-01-01

    In organisms with complex life cycles, physiological stressors during early life stages may have fitness-level impacts that are delayed into later stages or habitats. We tested the hypothesis that body size and date of metamorphosis, which are highly responsive to aquatic stressors, influence post-metamorphic survival and movement patterns in the terrestrial phase of an ephemeral pond-breeding frog by examining these traits in two populations of northern red-legged frogs (Rana aurora aurora). To increase variation of body size at metamorphosis, we manipulated food availability for 314 of 1045 uniquely marked tadpoles and estimated the probability that frogs survived and emigrated using concentric rings of drift fencing surrounding ponds and Bayesian capture-recapture modeling. The odds of surviving and emigrating from the ponds to the innermost drift fences, ???12 m, increased by factors of 2.20 (95% credibility intervals 1.39-4.23) and 2.54 (0.94-4.91) with each millimeter increase in snout-vent length and decreased by factors of 0.91 (0.85-0.96) and 0.89 (0.80-1.00) with each day's delay in metamorphosis for the two ponds. The odds of surviving and moving to the next ring of fencing, 12 m to ???40 m from the ponds, increased by a factor of 1.20 (0.45-4.06) with each millimeter increase in size. Our results demonstrated that body size and timing of metamorphosis relate strongly to the performance of newly metamorphosed frogs during their initial transition into terrestrial habitat. Carryover effects of aquatic stressors that reduce size and delay metamorphosis may have population-level impacts that are not expressed until terrestrial stages. Since changes in both aquatic and terrestrial systems are implicated in many amphibian declines, quantifying both immediate and delayed effects of stressors on demographic rates is critical to sound management. ?? 2006 by the Ecological Society of America.

  17. Structure of aquatic vegetation of a large lake, western border of the Brazilian Pantanal.

    Science.gov (United States)

    Cunha, N L; Delatorre, M; Rodrigues, R B; Vidotto, C; Gonçalves, F; Scremin-Dias, E; Damasceno-Júnior, G; Pott, V J; Pott, A

    2012-08-01

    Studies on Neotropical aquatic macrophytes have increased in recent decades, however species richness in wetlands of South America is far from being fully known. In addition, studies having an ecological approach are scarce in the Pantanal. Rapid assessments are essential for gaining knowledge of the biodiversity in the region. This study was performed in five sites of the Baía do Castelo, the western border of the Brazilian Pantanal, which included wild-rice patches, floating mats and floating meadows. At each site, plots of 0.5 × 0.5 m were set (n = 137), species of aquatic macrophytes were identified, their coverage was measured and the plot depth was estimated. We recorded 57 species in 26 families, of which Poaceae was the richest. The most frequent and abundant species was Commelina schomburgkiana; the second most frequent was Oryza latifolia,followed by Leersia hexandra, Enydra radicans and Pityrogramma calomelanos. The latter species was second in cover, followed by Pontederia rotundifolia, Eichhornia azurea, E. crassipes and Enydra radicans. These five species and C. schomburgkiana (the most abundant) together represent more than half of the coverage on the lake. Pontederia rotundifolia, Ludwigia helminthorrhiza, Pistia stratiotes, E. azurea, E. crassipes, Enydra radicans and Panicum elephantipes were strongly associated with deeper areas, while Oryza latifolia, Leersia hexandra and Salvinia auriculata were prevalent in shallow areas. Pityrogramma calomelanos, Ludwigia nervosa, Ipomoea alba, Cayaponia podantha, Polygonum acuminatum, Rhynchanthera novemnervia and Ludwigia leptocarpa were highly correlated with floating meadows. The structure of the habitat, natural dynamics and zonation of aquatic vegetation in the Baía do Castelo seems to be influenced by a variation in water levels, which promotes spatial segregation, most likely due to competition and/habitat preference. PMID:22990823

  18. Why Care About Aquatic Insects: Uses, Benefits, and Services

    Science.gov (United States)

    Mayflies and other aquatic insects are common subjects of ecological research, and environmental monitoring and assessment. However, their important role in protecting and restoring aquatic ecosystems is often challenged, because their benefits and services to humans are not obv...

  19. Malheur NWR: Initial Survey Instructions for Lacustrine Submergent Aquatic Vegetation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Submergent aquatic vegetation (SAV) provides the foundation for wildlife use in aquatic systems. Sago pondweed is of particular significance in providing protein by...

  20. Vegetation development following stream/river restoration: more natural fluvial dynamics and morphology, return of aquatic and riparian plant species?

    Science.gov (United States)

    Soons, M. B.

    2012-04-01

    After centuries of human interventions in stream/river dynamics and morphology aimed at optimizing landscapes for agricultural and industrial purposes, new insights have inspired water managers to try and combine stream and river ecosystem functions with the conservation of biodiversity. Around the world, aquatic and riparian species have declined strongly due to pollution, destruction and fragmentation of their habitat, so that biodiversity conservation initiatives primarily focus on habitat restoration. In the past decades many stream and river restoration projects have been carried out and often hydrological dynamics and morphology have been restored to a more natural state. However, the successful restoration of aquatic and riparian habitats very often failed to result in restoration of their biodiversity. This lack of success from a biodiversity conservation perspective is usually attributed to 'dispersal limitation', meaning that the habitat may be restored, but species fail to reach the site and re-colonize it. Especially re-colonization by aquatic and riparian plant species is important, as such species function as ecosystem engineers: their presence alters fluvial dynamics and morphology, generates additional habitat heterogeneity and provides habitat and food for animal species. Following minor disturbances, re-colonization is often possible through locally remaining populations, by seeds in the seed bank or by surviving plant fragments. However, following major disturbances, colonization and establishment from other source populations are necessary. This usually occurs through dispersal of seeds (and in more aquatic species also by dispersal of vegetative fragments) into the restored wetland area. As dispersal occurs predominantly over short distances and source populations of aquatic and riparian species may be lacking in the surroundings, dispersal may be a limiting factor in the development of aquatic and riparian vegetation at a restored site. But

  1. Yakima Habitat Improvement Project Master Plan, Technical Report 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Golder Associates, Inc.

    2003-04-22

    The Yakima Urban Growth Area (UGA) is a developing and growing urban area in south-central Washington. Despite increased development, the Yakima River and its tributaries within the UGA continue to support threatened populations of summer steelhead and bull trout as well as a variety of non-listed salmonid species. In order to provide for the maintenance and recovery of these species, while successfully planning for the continued growth and development within the UGA, the City of Yakima has undertaken the Yakima Habitat Improvement Project. The overall goal of the project is to maintain, preserve, and restore functioning fish and wildlife habitat within and immediately surrounding the Yakima UGA over the long term. Acquisition and protection of the fish and wildlife habitat associated with key properties in the UGA will prevent future subdivision along riparian corridors, reduce further degradation or removal of riparian habitat, and maintain or enhance the long term condition of aquatic habitat. By placing these properties in long-term protection, the threat of development from continued growth in the urban area will be removed. To most effectively implement the multi-year habitat acquisition and protection effort, the City has developed this Master Plan. The Master Plan provides the structure and guidance for future habitat acquisition and restoration activities to be performed within the Yakima Urban Area. The development of this Master Plan also supports several Reasonable and Prudent Alternatives (RPAs) of the NOAA Fisheries 2000 Biological Opinion (BiOp), as well as the Water Investment Action Agenda for the Yakima Basin, local planning efforts, and the Columbia Basin Fish and Wildlife Authority's 2000 Fish and Wildlife Program. This Master Plan also provides the framework for coordination of the Yakima Habitat Improvement Project with other fish and wildlife habitat acquisition and protection activities currently being implemented in the area. As a

  2. Hungry Horse Dam fisheries mitigation program: Fish passage and habitat improvement in the Upper Flathead River basin

    International Nuclear Information System (INIS)

    In the past 50 years, dramatic changes have occurred in the Flathead Lake and River system. Degradation of fishery resources has been evident, in part due to deterioration of aquatic habitat and introduction of non-endemic fish and invertebrate species. Habitat loss has been attributed to many factors including the construction and operation of Hungry Horse Dam, unsound land use practices, urban development, and other anthropogenic and natural disturbances. Fish migration has also been limited by barriers such as dams and impassible culverts. Cumulatively, these factors have contributed to declines in the distribution and abundance of native fish populations. Recovery of fish populations requires that a watershed approach be developed that incorporates long-term aquatic habitat needs and promotes sound land use practices and cooperation among natural resource management agencies. In this document, the authors (1) describe completed and ongoing habitat improvement and fish passage activities under the Hungry Horse Fisheries Mitigation Program, (2) describe recently identified projects that are in the planning stage, and (3) develop a framework for identifying prioritizing, implementing, and evaluating future fish habitat improvement and passage projects

  3. Effects of Seven Fungicides on Non-Target Aquatic Fungi

    OpenAIRE

    Dijksterhuis, Jan; van Doorn, Tineke; Samson, Rob; Postma, Jaap

    2011-01-01

    Aquatic risk assessments for fungicides are carried out without information on their toxicity to non-target aquatic fungi. This might cause an underestimation of the toxic effects to the aquatic fungal community. This study focuses on the question whether recently derived concentrations limits for fungicides considered to protect populations of primary producers and (in)vertebrates also do protect the aquatic fungi. A panel of fungal species and Oomycetes was isolated and identified from unpo...

  4. Trapping Triatominae in Silvatic Habitats

    Directory of Open Access Journals (Sweden)

    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  5. Les communautés microbiennes des phytotelmes des Broméliacées : structure et influence de l'habitat, des conditions environnementales et des interactions biologiques

    OpenAIRE

    Brouard, Olivier

    2012-01-01

    Bromeliads are a large family of neotropical flowering plants. The leaves of many bromeliads are tightly interlocking, forming wells that collect water and organic detritus. These phytotelmata (plant-held water) provide habitat for numerous aquatic organisms ranging from microorganisms to vertebrates. In this aquatic ecosystem, detritus (usually leaf litter) form the basis of a food web upon which depends the nutrition of the bromeliad. In tropical forests, these phytotelmata form abundant na...

  6. Remote sensing for mapping natural habitats and their conservation status - New opportunities and challenges

    Science.gov (United States)

    Corbane, Christina; Lang, Stefan; Pipkins, Kyle; Alleaume, Samuel; Deshayes, Michel; García Millán, Virginia Elena; Strasser, Thomas; Vanden Borre, Jeroen; Toon, Spanhove; Michael, Förster

    2015-05-01

    Safeguarding the diversity of natural and semi-natural habitats in Europe is one of the aims set out by the Habitats Directive (Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora) and one of the targets of the European 2020 Biodiversity Strategy, and is to be accomplished by maintaining a favourable conservation status. To reach this aim a high-level understanding of the distribution and conditions of these habitats is needed. Remote sensing can considerably contribute to habitat mapping and their observation over time. Several European projects and a large number of scientific studies have addressed the issue of mapping and monitoring natural habitats via remote sensing and the deriving of indicators on their conservation status. The multitude of utilized remote sensing sensors and applied methods used in these studies, however, impede a common understanding of what is achievable with current state-of-the-art technologies. The aim of this paper is to provide a synthesis on what is currently feasible in terms of detection and monitoring of natural and semi-natural habitats with remote sensing. To focus this endeavour, we concentrate on those studies aimed at direct mapping of individual habitat types or discriminating between different types of habitats occurring in relatively large, spatially contiguous units. By this we uncover the potential of remote sensing to better understand the distribution of habitats and the assessment of their conservation status in Europe. Natural habitats are "terrestrial or aquatic areas distinguished by geographic, abiotic and biotic features, whether entirely natural or semi-natural" (HabDir). Biotopes are "the smallest geographical unit of the biosphere or of a habitat that can be delimited by convenient boundaries and is characterized by its biota" (Lincoln, 1998). The term 'remote sensing' as used in this context comprises advanced, computer-assisted analytical tools for information

  7. Effects of Surface-Water Diversions on Habitat Availability for Native Macrofauna, Northeast Maui, Hawaii

    Science.gov (United States)

    Gingerich, Stephen B.; Wolff, Reuben H.

    2005-01-01

    Effects of surface-water diversions on habitat availability for native stream fauna (fish, shrimp, and snails) are described for 21 streams in northeast Maui, Hawaii. Five streams (Waikamoi, Honomanu, Wailuanui, Kopiliula, and Hanawi Streams) were chosen as representative streams for intensive study. On each of the five streams, three representative reaches were selected: (1) immediately upstream of major surface-water diversions, (2) midway to the coast, and (3) near the coast. This study focused on five amphidromous native aquatic species (alamoo, nopili, nakea, opae, and hihiwai) that are abundant in the study area. The Physical Habitat Simulation (PHABSIM) System, which incorporates hydrology, stream morphology and microhabitat preferences to explore relations between streamflow and habitat availability, was used to simulate habitat/discharge relations for various species and life stages, and to provide quantitative habitat comparisons at different streamflows of interest. Hydrologic data, collected over a range of low-flow discharges, were used to calibrate hydraulic models of selected transects across the streams. The models were then used to predict water depth and velocity (expressed as a Froude number) over a range of discharges up to estimates of natural median streamflow. The biological importance of the stream hydraulic attributes was then assessed with the statistically derived suitability criteria for each native species and life stage that were developed as part of this study to produce a relation between discharge and habitat availability. The final output was expressed as a weighted habitat area of streambed for a representative stream reach. PHABSIM model results are presented to show the area of estimated usable bed habitat over a range of streamflows relative to natural conditions. In general, the models show a continuous decrease in habitat for all modeled species as streamflow is decreased from natural conditions. The PHABSIM modeling results

  8. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV), floating aquatic vegetation (FAV), and rare/sensitive coastal...

  9. Phylogenetic analysis of conservation priorities for aquatic mammals and their terrestrial relatives, with a comparison of methods.

    Directory of Open Access Journals (Sweden)

    Laura J May-Collado

    Full Text Available BACKGROUND: Habitat loss and overexploitation are among the primary factors threatening populations of many mammal species. Recently, aquatic mammals have been highlighted as particularly vulnerable. Here we test (1 if aquatic mammals emerge as more phylogenetically urgent conservation priorities than their terrestrial relatives, and (2 if high priority species are receiving sufficient conservation effort. We also compare results among some phylogenetic conservation methods. METHODOLOGY/PRINCIPAL FINDINGS: A phylogenetic analysis of conservation priorities for all 620 species of Cetartiodactyla and Carnivora, including most aquatic mammals. Conservation priority ranking of aquatic versus terrestrial species is approximately proportional to their diversity. However, nearly all obligated freshwater cetartiodactylans are among the top conservation priority species. Further, ∼74% and 40% of fully aquatic cetartiodactylans and carnivores, respectively, are either threatened or data deficient, more so than their terrestrial relatives. Strikingly, only 3% of all 'high priority' species are thought to be stable. An overwhelming 97% of these species thus either show decreasing population trends (87% or are insufficiently known (10%. Furthermore, a disproportional number of highly evolutionarily distinct species are experiencing population decline, thus, such species should be closely monitored even if not currently threatened. Comparison among methods reveals that exact species ranking differs considerably among methods, nevertheless, most top priority species consistently rank high under any method. While we here favor one approach, we also suggest that a consensus approach may be useful when methods disagree. CONCLUSIONS/SIGNIFICANCE: These results reinforce prior findings, suggesting there is an urgent need to gather basic conservation data for aquatic mammals, and special conservation focus is needed on those confined to freshwater. That

  10. Cobbania corrugata gen. et comb. nov. (Araceae): a floating aquatic monocot from the Upper Cretaceous of western North America.

    Science.gov (United States)

    Stockey, Ruth A; Rothwell, Gar W; Johnson, Kirk R

    2007-04-01

    The fossil record of aquatic flowering plants broadens our understanding of their former diversity and origins from terrestrial ancestors. This paper describes a floating aquatic monocot from 71 whole plants and several isolated leaf fragments from Upper Cretaceous oxbow lake sediments in the Dinosaur Park Formation, Alberta, Canada. The new material is represented by rosettes of leaves and roots attached to short stems that are interconnected by stolons and corresponds to the fossil aroid originally described as Pistia corrugata Lesquereux. Up to six plants have been found interconnected on a single slab suggesting that these plants grew in extensive floating mats covering lakes and calm stretches of rivers. Stems have up to six leaves and large numbers of branched aquatic roots. The leaf is trumpet-shaped with an elongate clasping petiole, large aerenchymatous base, and a nearly circular blade rim. Leaf bases are often filled with sediment giving the leaf the appearance of having a basal pouch. Petioles have 6-9 veins that divide into an upper and lower set, and veins converge at an apical notch. A submarginal collective vein and at least two marginal veins with branching veins form the leaf rim. A series of dichotomizing and anastomosing veins characterize the adaxial leaf surface. Tertiary and quaternary veins form polygonal areolae. Leaf surfaces are covered in trichomes that, like those in Pistia stratiotes, probably aided in buoyancy. A reconstruction of the plant is presented. Based on unique leaf morphology, these fossil plants are clearly not assignable to the genus Pistia and are described as Cobbania corrugata (Lesquereux) Stockey, Rothwell et Johnson gen. et comb. nov. Recent systematic analyses using molecular characters resolve two separate origins of floating aquatic aroids included in the duckweeds and the genus Pistia. This new fossil genus increases our understanding of colonization of aquatic habitats by revealing a third possible origin of the

  11. South Fork Shenandoah River habitat-flow modeling to determine ecological and recreational characteristics during low-flow periods

    Science.gov (United States)

    Krstolic, Jennifer L.; Ramey, R. Clay

    2012-01-01

    The ecological habitat requirements of aquatic organisms and recreational streamflow requirements of the South Fork Shenandoah River were investigated by the U.S. Geological Survey in cooperation with the Central Shenandoah Valley Planning District Commission, the Northern Shenandoah Valley Regional Commission, and Virginia Commonwealth University. Physical habitat simulation modeling was conducted to examine flow as a major determinant of physical habitat availability and recreation suitability using field-collected hydraulic habitat variables such as water depth, water velocity, and substrate characteristics. Fish habitat-suitability criteria specific to the South Fork Shenandoah River were developed for sub-adult and adult smallmouth bass (Micropterus dolomieu), juvenile and sub-adult redbreast sunfish (Lepomis auritus), spotfin or satinfin shiner (Cyprinella spp), margined madtom (Noturus insignis),and river chub (Nocomis micropogon). Historic streamflow statistics for the summer low-flow period during July, August, and September were used as benchmark low-flow conditions and compared to habitat simulation results and water-withdrawal scenarios based on 2005 withdrawal data. To examine habitat and recreation characteristics during droughts, daily fish habitat or recreation suitability values were simulated for 2002 and other selected drought years. Recreation suitability during droughts was extremely low, because the modeling demonstrated that suitable conditions occur when the streamflows are greater than the 50th percentile flow for July, August, and September. Habitat availability for fish is generally at a maximum when streamflows are between the 75th and 25th percentile flows for July, August, and September. Time-series results for drought years, such as 2002, showed that extreme low-flow conditions less than the 5th percentile of flow for July, August, and September corresponded to below-normal habitat availability for both game and nongame fish in the

  12. Terrestrial contributions to the aquatic food web in the middle Yangtze River.

    Science.gov (United States)

    Wang, Jianzhu; Gu, Binhe; Huang, Jianhui; Han, Xingguo; Lin, Guanghui; Zheng, Fawen; Li, Yuncong

    2014-01-01

    Understanding the carbon sources supporting aquatic consumers in large rivers is essential for the protection of ecological integrity and for wildlife management. The relative importance of terrestrial and algal carbon to the aquatic food webs is still under intensive debate. The Yangtze River is the largest river in China and the third longest river in the world. The completion of the Three Gorges Dam (TGD) in 2003 has significantly altered the hydrological regime of the middle Yangtze River, but its immediate impact on carbon sources supporting the river food web is unknown. In this study, potential production sources from riparian and the main river channel, and selected aquatic consumers (invertebrates and fish) at an upstream constricted-channel site (Luoqi), a midstream estuarine site (Huanghua) and a near dam limnetic site (Maoping) of the TGD were collected for stable isotope (δ13C and δ15N) and IsoSource analyses. Model estimates indicated that terrestrial plants were the dominant carbon sources supporting the consumer taxa at the three study sites. Algal production appeared to play a supplemental role in supporting consumer production. The contribution from C4 plants was more important than that of C3 plants at the upstream site while C3 plants were the more important carbon source to the consumers at the two impacted sites (Huanghua and Maoping), particularly at the midstream site. There was no trend of increase in the contribution of autochthonous production from the upstream to the downstream sites as the flow rate decreased dramatically along the main river channel due to the construction of TGD. Our findings, along with recent studies in rivers and lakes, are contradictory to studies that demonstrate the importance of algal carbon in the aquatic food web. Differences in system geomorphology, hydrology, habitat heterogeneity, and land use may account for these contradictory findings reported in various studies. PMID:25047656

  13. Terrestrial contributions to the aquatic food web in the middle Yangtze River.

    Directory of Open Access Journals (Sweden)

    Jianzhu Wang

    Full Text Available Understanding the carbon sources supporting aquatic consumers in large rivers is essential for the protection of ecological integrity and for wildlife management. The relative importance of terrestrial and algal carbon to the aquatic food webs is still under intensive debate. The Yangtze River is the largest river in China and the third longest river in the world. The completion of the Three Gorges Dam (TGD in 2003 has significantly altered the hydrological regime of the middle Yangtze River, but its immediate impact on carbon sources supporting the river food web is unknown. In this study, potential production sources from riparian and the main river channel, and selected aquatic consumers (invertebrates and fish at an upstream constricted-channel site (Luoqi, a midstream estuarine site (Huanghua and a near dam limnetic site (Maoping of the TGD were collected for stable isotope (δ13C and δ15N and IsoSource analyses. Model estimates indicated that terrestrial plants were the dominant carbon sources supporting the consumer taxa at the three study sites. Algal production appeared to play a supplemental role in supporting consumer production. The contribution from C4 plants was more important than that of C3 plants at the upstream site while C3 plants were the more important carbon source to the consumers at the two impacted sites (Huanghua and Maoping, particularly at the midstream site. There was no trend of increase in the contribution of autochthonous production from the upstream to the downstream sites as the flow rate decreased dramatically along the main river channel due to the construction of TGD. Our findings, along with recent studies in rivers and lakes, are contradictory to studies that demonstrate the importance of algal carbon in the aquatic food web. Differences in system geomorphology, hydrology, habitat heterogeneity, and land use may account for these contradictory findings reported in various studies.

  14. Habitat Suitability Index Models: Red king crab

    Science.gov (United States)

    Jewett, Stephen C.; Onuf, Christopher P.

    1988-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for evaluating habitat of different life stages of red king crab (Paralithodes camtschatica). A model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat) in Alaskan coastal waters, especially in the Gulf of Alaska and the southeastern Bering Sea. HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  15. Aluminium in UK rivers: a need for integrated research related to kinetic factors, colloidal transport, carbon and habitat.

    Science.gov (United States)

    Neal, Colin; Rowland, Philip; Neal, Margaret; Jarvie, Helen P; Lawlor, Alan; Sleep, Darren; Scholefield, Paul

    2011-08-01

    Dissolved aluminium concentrations ([Al]) in the hydrogeochemistry in river systems there is a need to integrate research that moves from equilibrium to kinetic and colloidal consideration including the critical issues of organic and inorganic controls within the context of bioavailability and aquatic stress. The colloidal Al may well be of low environmental concern to fish and other factors such as habitat may well be critical. PMID:21701704

  16. Habitat use of migratory bats killed during autumn at wind turbines.

    Science.gov (United States)

    Voigt, Christian C; Lindecke, Oliver; Schönborn, Sophia; Kramer-Schadt, Stephanie; Lehmann, David

    2016-04-01

    The killing of large numbers of migratory bats at wind turbines is a pressing conservation problem. Even though avoidance and mitigation measures could benefit from a better knowledge of the species' migratory habits, we lack basic information about what habitats and corridors bats use during migration. We studied the isotopic niche dimensions of three bat species that are frequently killed at wind turbines in Germany: non-migratory Pipistrellus pipistrellus, mid-distance migratory Nyctalus noctula, and long- distance migratory Pipistrellus nathusii. We measured stable carbon and nitrogen isotope ratios (δ¹³C, δ¹⁵N) in five tissues that differed in isotopic retention time (fur, wing membrane tissue, muscle, liver, blood) to shed light on the species-specific habitat use during the autumn migration period using standard ellipse areas (SEAc). Further, we used stable isotope ratios of non-exchangeable hydrogen (δ²H(K)) in fur keratin to assess the breeding origin of bats. We inferred from isotopic composition (δ¹³C, δ¹⁵N) of fur keratin that isotopic niche dimensions of P. nathusii was distinct from that of N. noctula and P. pipistrellus, probably because P. nathusii was using more aquatic habitats than the other two species. Isoscape origin models supported that traveled distances before dying at wind turbines was largest for P. nathusii, intermediate for N. noctula, and shortest for P. pipistrellus. Isotopic niche dimensions calculated for each sample type separately reflected the species' migratory behavior. Pipistrellus pipistrellus and N. noctula showed similar isotopic niche breadth across all tissue types, whereas SEAc values of P. nathusii increased in tissues with slow turnaround time. Isotopic data suggested that P. nathusii consistently used aquatic habitats throughout the autumn period, whereas N. noctula showed a stronger association with terrestrial habitats during autumn compared to the pre-migration period.

  17. Wildlife and biological resources: Chapter 5 in A synthesis of aquatic science for management of Lakes Mead and Mohave

    Science.gov (United States)

    Chandra, Sudeep; Abella, Scott R.; Albrecht, Brandon A.; Barnes, Joseph G.; Engel, E. Cayenne; Goodbred, Steven L.; Holden, Paul B.; Kegerries, Ron B.; Jaeger, Jef R.; Orsak, Erik; Rosen, Michael R.; Sjöberg, Jon; Wong, Wai Hing

    2012-01-01

    The creation of Lakes Mead and Mohave drastically changed habitats originally found along their region of the historical Colorado River. While still continuing to provide habitat conditions that support a rich diversity of species within the water, along shorelines, and in adjacent drainage areas, the reservoirs contain organisms that are both native and non-native to the Colorado River drainage (fig. 5-1). The diversity of species within these lakes continues to change with time due to changing habitat conditions, the invasion of non-native species, and extirpations of native species. From the bottom of the food web to the top predators, all organisms within the ecosystem are interconnected in food webs or food-chain networks. As non-native invasive species continue to be introduced into the lakes, alterations to the food web, species competition, and species predation likely will continue to change the ecosystem and populations of native organisms. Following an overview of the food web, this chapter summarizes information on aquatic and aquatic-dependent wildlife at Lakes Mead and Mohave and their relationships within the food web from members of lower trophic levels to the highest: phytoplankton, invertebrates, including zooplankton, and macroinvertebrates; fishes; and birds. The following sections describe the biological diversity, limiting factors, and ecological functions of these groups in Lake Mead, and to a lesser extent, in Lake Mohave.

  18. Delineation of level III aquatic ecological function regionalization in the Taihu Lake basin%太湖流域水生态功能三级分区

    Institute of Scientific and Technical Information of China (English)

    高永年; 高俊峰; 陈垌烽; 许妍; 赵家虎

    2012-01-01

    Aquatic ecoregions have been used as spatial units for aquatic ecosystem management at the watershed scale. According to the protection requirements and characteristics of aquatic ecosystems in the Taihu Lake basin, the main purpose and the principles of level III aquatic ecological function regionalization delineation in this basin were proposed. Then the indicators for delineating level III aquatic ecological function regionalization were established based on regionalization objective and principles. The indicators for delineating level Ili aquatic ecological function regionalization in the non-Taihu Lake area included benthic Shannon-Wiener diversity index, chlorophyll content, water habitat types and benthic indicator species types (including Ephemera, Bivalvia, snail, Chironomidae and Oligochaeta), and the regionalization indicators for delineating level III aquatic ecological function regionalization in the Taihu Lake area included benthic Shannon-Wiener diversity index, chlorophyll content, water flow velocity and benthic indicator species (including Oligochaeta, Chironomidae class, Bivalvia, snail and others) ratio. With the aid of GIS technology, the spatial distribution of the indicators for level III aquatic ecological function regionalization delineation was identified based on the raster data from 1106 aquatic ecoregion function units in the non-Taihu Lake area and 3568 aquatic ecoregion function units in the Taihu Lake area, respectively. Two-step spatial clustering analysis approach and manual-assisted method were used to delineate level III aquatic ecological function zones. Then the Taihu Lake basin was divided into 21 level III aquatic ecological function zones. Moreover, the characteristics of the 21 zones were summarized, showing that there were significant differences in the aspects such as topography, soil type, water quality and aquatic ecology. The results of quantitative comparison of aquatic life also indicated that the benthic dominant

  19. Mosquito larval habitat mapping using remote sensing and GIS: Implications of coalbed methane development and West Nile virus

    Energy Technology Data Exchange (ETDEWEB)

    Zou, L.; Miller, S.N.; Schmidtmann, E.T. [University of Wyoming, Laramie, WY (United States). Dept. of Renewable Resources

    2006-09-15

    Potential larval habitats of the mosquito Culex tarsalis (Coquillett), implicated as a primary vector of West Nile virus in Wyoming, were identified using integrated remote sensing and geographic information system (GIS) analyses. The study area is in the Powder River Basin of north central Wyoming, an area that has been undergoing a significant increase in coalbed methane gas extractions since the late 1990s. Large volumes of water are discharged, impounded, and released during the extraction of methane gas, creating aquatic habitats that have the potential to support immature mosquito development. Landsat TM and ETM + data were initially classified into spectrally distinct water and vegetation classes, which were in turn used to identify suitable larval habitat sites. This initial habitat classification was refined using knowledge-based GIS techniques requiring spatial data layers for topography, streams, and soils to reduce the potential for overestimation of habitat. Accuracy assessment was carried out using field data and high-resolution aerial photography commensurate with one of the Landsat images. The classifier can identify likely habitat for ponds larger than 0.8 ha (2 acres) with generally satisfactory results (72.1%) with a lower detection limit of approximate to 0.4 ha (1 acre). Results show a 75% increase in potential larval habitats from 1999 to 2004 in the study area, primarily because of the large increase in small coalbed methane water discharge ponds. These results may facilitate mosquito abatement programs in the Powder River Basin with the potential for application throughout the state and region.

  20. Derivation of habitat-specific dissolved oxygen criteria for Chesapeake Bay and its tidal tributaries

    Science.gov (United States)

    Batiuk, R.A.; Breitburg, D.L.; Diaz, R.J.; Cronin, T. M.; Secor, D.H.; Thursby, G.

    2009-01-01

    The Chesapeake 2000 Agreement committed its state and federal signatories to "define the water quality conditions necessary to protect aquatic living resources" in the Chesapeake Bay (USA) and its tidal tributaries. Hypoxia is one of the key water quality issues addressed as a result of the above Agreement. This paper summarizes the protection goals and specific criteria intended to achieve those goals for addressing hypoxia. The criteria take into account the variety of Bay habitats and the tendency towards low dissolved oxygen in some areas of the Bay. Stressful dissolved oxygen conditions were characterized for a diverse array of living resources of the Chesapeake Bay by different aquatic habitats: migratory fish spawning and nursery, shallow-water, open-water, deep-water, and deep-channel. The dissolved oxygen criteria derived for each of these habitats are intended to protect against adverse effects on survival, growth, reproduction and behavior. The criteria accommodate both spatial and temporal aspects of low oxygen events, and have been adopted into the Chesapeake Bay states - Maryland, Virginia, and Delaware - and the District of Columbia's water quality standards regulations. These criteria, now in the form of state regulatory standards, are driving an array of land-based and wastewater pollution reduction actions across the six-watershed.

  1. Habitats: staging life and art

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2004-01-01

    -relevantinformation. The habitat concept was originally proposed as a help to understandmobile context-sensitive technology, but turns out to have much broader applications. Thepresent version of the approach uses activity theory and semiotics as the basic theoretical un-derpinnings.The paper offers a notation for specifying...

  2. A comparison of the functional traits of common reed (Phragmites australis) in northern China: aquatic vs. terrestrial ecotypes.

    Science.gov (United States)

    Li, Liping; Han, Wenxuan; Thevs, Niels; Jia, Xiuhong; Ji, Chengjun; Jin, Dongmei; He, Ping; Schmitt, Armin O; Cirella, Giuseppe Tommaso; Zerbe, Stefan

    2014-01-01

    Common reed (Phragmites australis (Cav.) Trin. ex Steud.) is distributed widely throughout the world with various ecotypes. This research compares the functional traits and biomass allocation patterns of two contrasting reed ecotypes. Twelve pairs of aquatic and terrestrial reed samples were collected in northern China. Significant differences in functional traits between the two reed ecotypes were observed, while biomass allocation patterns of reed organs did not differ significantly except for at the root. The dry matter content (DMC) in the whole of the reed plant, leaf, root, and rhizome was higher; while the specific leaf area (SLA) and specific root length (SRL) were lower in terrestrial versus aquatic reed. The biomass allocation in organs of the two forms of reed was isometric, only root in the terrestrial habitat increased faster with an increase in the whole plant biomass. It can be affirmed that aquatic and terrestrial reed that adapt to different environments generally has distinct leaf and root functional traits but isometric biomass allocation patterns. This suggests different resource acquisition strategies: (1) aquatic reed grows faster with high SLA and SRL and is more responsive to the environment, while (2) terrestrial reed with high DMC grows slower and is less responsive to the adverse environment (e.g. dry soil conditions).

  3. A comparison of the functional traits of common reed (Phragmites australis in northern China: aquatic vs. terrestrial ecotypes.

    Directory of Open Access Journals (Sweden)

    Liping Li

    Full Text Available Common reed (Phragmites australis (Cav. Trin. ex Steud. is distributed widely throughout the world with various ecotypes. This research compares the functional traits and biomass allocation patterns of two contrasting reed ecotypes. Twelve pairs of aquatic and terrestrial reed samples were collected in northern China. Significant differences in functional traits between the two reed ecotypes were observed, while biomass allocation patterns of reed organs did not differ significantly except for at the root. The dry matter content (DMC in the whole of the reed plant, leaf, root, and rhizome was higher; while the specific leaf area (SLA and specific root length (SRL were lower in terrestrial versus aquatic reed. The biomass allocation in organs of the two forms of reed was isometric, only root in the terrestrial habitat increased faster with an increase in the whole plant biomass. It can be affirmed that aquatic and terrestrial reed that adapt to different environments generally has distinct leaf and root functional traits but isometric biomass allocation patterns. This suggests different resource acquisition strategies: (1 aquatic reed grows faster with high SLA and SRL and is more responsive to the environment, while (2 terrestrial reed with high DMC grows slower and is less responsive to the adverse environment (e.g. dry soil conditions.

  4. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand.

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  5. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  6. Aquatic invertebrate sampling at selected outfalls in Operable Unit 1082; Technical areas 9, 11, 16 and 22

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S.

    1995-09-01

    The Ecological Studies Team (EST) of ESH-20 at Los Alamos National Laboratory conducted preliminary aquatic sampling at outfalls within Operable Unit 1082 and nearby natural waterways. Eleven outfalls were sampled a total of eighteen times. Three natural waterways (upper Pajarito Canyon, Starmer`s Gulch, and Bulldog Spring) in the vicinity were sampled a total of six times. At most sites, EST recorded hydrological condition, physico-chemical parameters, wildlife uses, and vegetation. At each outfall with water and each natural waterway, EST collected an aquatic invertebrate sample which was analyzed by taxa composition, Wilhm`s biodiversity index, the community tolerance quotient (CTQ), and density. The physico-chemical parameters at most outfalls and natural waterways fell within the normal range of natural waters in the area. However, the outfalls are characterized by low biodiversity and severely stressed communities composed of a restricted number of taxa. The habitat at the other outfalls could probably support well-developed aquatic communities if sufficient water was available. At present, the hydrology at these outfalls is too slight and/or sporadic to support such a community in the foreseeable future. In contrast to the outfalls, the natural waterways of the area had greater densities of aquatic invertebrates, higher biodiversities, and lower CTQs.

  7. Toxicological effects of pyrethroids on non-target aquatic insects.

    Science.gov (United States)

    Antwi, Frank B; Reddy, Gadi V P

    2015-11-01

    The toxicological effects of pyrethroids on non-target aquatic insects are mediated by several modes of entry of pyrethroids into aquatic ecosystems, as well as the toxicological characteristics of particular pyrethroids under field conditions. Toxicokinetics, movement across the integument of aquatic insects, and the toxicodynamics of pyrethroids are discussed, and their physiological, symptomatic and ecological effects evaluated. The relationship between pyrethroid toxicity and insecticide uptake is not fully defined. Based on laboratory and field data, it is likely that the susceptibility of aquatic insects (vector and non-vector) is related to biochemical and physiological constraints associated with life in aquatic ecosystems. Understanding factors that influence aquatic insects susceptibility to pyrethroids is critical for the effective and safe use of these compounds in areas adjacent to aquatic environments.

  8. Measuring Complexity in an Aquatic Ecosystem

    OpenAIRE

    Fernandez, Nelson; Gershenson, Carlos

    2013-01-01

    We apply formal measures of emergence, self-organization, homeostasis, autopoiesis and complexity to an aquatic ecosystem; in particular to the physiochemical component of an Arctic lake. These measures are based on information theory. Variables with an homogeneous distribution have higher values of emergence, while variables with a more heterogeneous distribution have a higher self-organization. Variables with a high complexity reflect a balance between change (emergence) and regularity/orde...

  9. Toxicity of trifluoroacetate to aquatic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Berends, A.G.; Rooij, C.G. de [Solvay S.A., Brussels (Belgium); Boutonnet, J.C. [Elf Atochem, Levallois-Perret (France); Thompson, R.S. [Zeneca Ltd., Devon (United Kingdom). Brixham Environmental Lab.

    1999-05-01

    As a result of the atmospheric degradation of several hydrofluorocarbons and hydrochlorofluorocarbons, trifluoroacetate (TFA) will be formed. Through precipitation, TFA will enter aquatic ecosystems. To evaluate the impact on the aquatic environment, an aquatic toxicity testing program was carried out with sodium trifluoroacetate (NaTFA). During acute toxicity tests, no effects of NaTFA on water fleas (Daphnia magna) and zebra fish (Danio retrio) were found at a concentration of 1,200 mg/L. A 7-d study with duckweed (Lemna gibba Ge) revealed a NOEC of 300 mg/L. On the basis of the results of five toxicity tests with Selenastrum capricornutum, they determined a NOEC of 0.12 mg/L. However, algal toxicity tests with NaTFA and Chlorella vulgaris, Scenedesmus subspicatus, Chlamydomonas reinhardtii, Dunaliella tertiolecta, Eugelan gracilis, Phaeodactylum tricornutum, Navicula pelliculosa, Skeletonema costatum, Anabaena flos-aquae, and Microcystis aeruginosa resulted in EC50 values that were all higher than 100 mg/L. The toxicity of TFA to S. capricornutum could be due to metabolic defluorination to monofluoroacetate (MFA), which is known to inhibit the citric acid cycle. A toxicity test with MFA and S. capricornutum revealed it to be about three orders of magnitude more toxic than TFA. However, a bioactivation study revealed that defluorination of TFA was less than 4%. On the other hand, S. capricornutum exposed to a toxic concentration of NaTFA showed a recovery of growth when citric acid was added, suggesting that TFA (or a metabolite of TFA) interferes with the citric acid cycle. A recovery of the growth of S. capricornutum was also found when TFA was removed from the test solutions. Therefore, TFA should be considered algistatic and not algicidic for S. capricornutum. On the basis of the combined results of the laboratory tests and a previously reported semi-field study, they can consider a TFA concentration of 0.10 mg/L as safe for the aquatic ecosystem.

  10. Aspects of Aquatic Pollution in Nigeria

    OpenAIRE

    A.T. Ekubo; J.F.N. Abowei

    2011-01-01

    Water pollution is a major problem in the global context. Yet aquatic resources consists of extremely wide range of floral and fauna resources which offer a broad array of goods with potential utilitarian application in agriculture, innovative industry and the pharmaceutical industry which renders valuable benefits and services. The slow poisoning of the waters is witnessed in Nigeria and the destruction of vegetation and agricultural land by oil spills which occur during petroleum operations...

  11. Mechanical performance of aquatic rowing and flying.

    OpenAIRE

    Walker, J.A.; Westneat, M. W.

    2000-01-01

    Aquatic flight, performed by rowing or flapping fins, wings or limbs, is a primary locomotor mechanism for many animals. We used a computer simulation to compare the mechanical performance of rowing and flapping appendages across a range of speeds. Flapping appendages proved to be more mechanically efficient than rowing appendages at all swimming speeds, suggesting that animals that frequently engage in locomotor behaviours that require energy conservation should employ a flapping stroke. The...

  12. Stream Habitat Reach Summary - NCWAP [ds158

    Data.gov (United States)

    California Department of Resources — The Stream Habitat - NCWAP - Reach Summary [ds158] shapefile contains in-stream habitat survey data summarized to the stream reach level. It is a derivative of the...

  13. Mingo National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mingo National Wildlife Refuge Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern at...

  14. Incipient habitat race formation in an amphibian.

    Science.gov (United States)

    Van Buskirk, J

    2014-03-01

    Theory defines conditions under which sympatric speciation may occur, and several possible examples of the process in action have been identified. In most cases, organisms specialize onto habitats that fall into discrete categories, such as host species used by herbivores and parasites. Ecological specialization within a continuous habitat gradient is theoretically possible, but becomes less likely with increasing gene flow among clinal habitat types. Here, I show that habitat race formation is underway in a frog, Rana temporaria, along a continuous and spatially mosaic habitat gradient. Tadpoles from 23 populations raised in an outdoor mesocosm experiment showed adaptive phenotypic variation correlated with the predator density in their pond of origin. A survey of microsatellite markers in 48 populations found that neutral genetic divergence was enhanced between ponds with very different densities of predators. This represents a new example of habitat specialization along a continuous habitat gradient with no spatial autocorrelation in habitat. PMID:26230250

  15. Lower Hatchie Forest Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Lower Hatchie National Wildlife Refuge Forest Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources...

  16. Montezuma National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Montezuma National Wildlife Refuge Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern...

  17. Chinook Critical Habitat, Coast - NOAA [ds124

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Chinook Critical Habitat as well as habitat type and quality in the California Coastal Evolutionary Significant Unit (ESU -...

  18. Agassiz National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Agassiz National Wildlife Refuge Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern at...

  19. critical_habitat_by_HUC10

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — CriticalHabitatWatershedOccupation is a digital hydrologic unit boundary layer of Level 5 (10-digit) WATERSHEDs for Maine that describe salmon critical habitat...

  20. Benthic Habitats of the Florida Keys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The benthic habitats of the Florida Keys were mapped from a series of 450 aerial photographs. Ecologists outlined the boundaries of specific habitat types by...