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Sample records for lontra longicaudis annectens

  1. First record of the neotropical otter Lontra longicaudis annectens (Carnivora, Mustelidae in the estuary Boca Negra, Jalisco, Mexico: an approach to understanding its diet.

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    Rodríguez-Uribe, M.C.

    2015-01-01

    Full Text Available The first record of the neotropical otter Lontra longicaudis annectens in the estuary Boca Negra, Jalisco, Mexico is presented. It includes relevant information about its diet and a photograph in its natural habitat is showed.

  2. Hypoxanthine-guanine phosphoribosyltransferase and inosine 5’-monophosphate dehydrogenase activities in three mammalian species: aquatic (Mirounga angustirostris, semiaquatic (Lontra longicaudis annectens and terrestrial (Sus scrofa

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    Myrna eBarjau Perez-Milicua

    2015-07-01

    Full Text Available Aquatic and semiaquatic mammals have the capacity of breath hold (apnea diving. Northern elephant seals (Mirounga angustirostris have the ability to perform deep and long duration dives; during a routine dive, adults can hold their breath for 25 min. Neotropical river otters (Lontra longicaudis annectens can hold their breath for about 30 sec. Such periods of apnea may result in reduced oxygen concentration (hypoxia and reduced blood supply (ischemia to tissues. Production of adenosine 5’-triphosphate (ATP requires oxygen, and most mammalian species, like the domestic pig (Sus scrofa, are not adapted to tolerate hypoxia and ischemia, conditions that result in ATP degradation. The objective of this study was to explore the differences in purine synthesis and recycling in erythrocytes and plasma of three mammalian species adapted to different environments: aquatic (northern elephant seal (n=11, semiaquatic (neotropical river otter (n=4 and terrestrial (domestic pig (n=11. Enzymatic activity of hypoxanthine-guanine phosphoribosyltransferase (HGPRT was determined by spectrophotometry, and activity of inosine 5’-monophosphate dehydrogenase (IMPDH and the concentration of hypoxanthine (HX, inosine 5’-monophosphate (IMP, adenosine 5’-monophosphate (AMP, adenosine 5’-diphosphate (ADP, ATP, guanosine 5’-diphosphate (GDP, guanosine 5’-triphosphate (GTP, and xanthosine 5’-monophosphate (XMP were determined by high-performance liquid chromatography (HPLC. The activities of HGPRT and IMPDH and the concentration of HX, IMP, AMP, ADP, ATP, GTP and XMP in erythrocytes of domestic pigs were higher than in erythrocytes of northern elephant seals and river otters. These results suggest that under basal conditions (no diving, sleep apnea or exercise, aquatic and semiaquatic mammals have less purine mobilization than their terrestrial counterparts.

  3. Depredación de aves acuáticas por la nutria neotropical (Lontra longicaudis annectens, en el río Yaqui, Sonora, México Aquatic bird predation by neotropical river otter (Lontra longicaudis annectens, at Rio Yaqui, Sonora, Mexico

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    Juan Pablo Gallo-Reynoso

    2008-06-01

    Full Text Available Se registra la depredación de aves acuáticas por la nutria neotropical (L. longicaudis annectens en el río Yaqui, Sonora. Se colectaron e identificaron 25 cráneos, porciones de esqueleto postcraneal y plumas de aves encontrados en los comederos de las nutrias; las especies identificadas fueron el cormorán neotropical (Phalacrocorax brasilianus con 16 individuos, el pato de collar (Anas platyrhynchos diazi, 4 individuos; la garza blanca (Ardea alba, 3 individuos; el huaco de corona amarilla (Nyctanassa violacea y el pelícano café (Pelecanus occidentalis, ambos con 1 individuo. En los peces se encontró la tilapia del género Oreochromis. Probablemente los hábitos alimenticios de esta especie responden a la estacionalidad y al consumo de presas más disponibles en el hábitat. Estos registros confirman que las nutrias de río son depredadores oportunistas cuya dieta tiene una amplio rango de uso de especies de los ambientes riparios, además dichos registros son una razón más para considerar la nutria neotropical como especie sombrilla para la conservación de ecosistemas completos, ya que su presencia es un indicador de alta disponibilidad energética y de alta biodiversidad.We report the predation of aquatic birds by neotropical river otters (L. longicaudis annectens at Río Yaqui, Sonora. As many as 25 skulls, post-cranial skeletons and feathers were found at river otter feeding sites. The neotropical cormorant (Phalacrocorax brasilianus was the most predated bird with 16 individuals, followed by Mexican mallard (Anas platyrhynchos diazi with 4 individuals, great egret (Ardea alba with 3 individuals, yellow-crowned night-heron (Nyctanassa violacea, and brown pelican (Pelecanus occidentalis, both with 1 individual. With respect to fish, the tilapia Oreochromis, was the only species found in scats. Neotropical river otter feeding habits were associated with food availability at different seasons of the year. These records show that

  4. Trophic ecology of Lontra longicaudis (Carnivora, Mustelidae in lotic and semilotic environments in southeastern Brazil

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    Lívia B. Santos

    2012-09-01

    Full Text Available Lontra longicaudis (Olfers, 1818 (Carnivora, Mustelidae is a semi-aquatic animal spread through the Central and South America, except in Chile. The implantation of a hydroelectric power plant along a river alters the dynamics of the watercourse, transforming a lotic environment into a lentic or semilotic one, what can damage the otter's feeding. From April 2008 to March 2009 we analysed the otter's food habits in lotic (streamlet and semilotic (hydroelectric reservoir environments of Paranapanema Valley, in southeastern Brazil. Aiming to compare the otter's diet of these two environments, we analyzed statistically the frequency of occurrence of main items in the scats. Fishes represent the base of the diet both in the reservoir and in the streamlet and, despite of the total otter's diet showing up similarities in the two environments, the results evidenced modifications on the fish species consumed between them. In the reservoir the otters ate more exotic fish Oreochromis niloticus (Linnaeus, 1758 probably because it is an easy capture prey in this place. The fact that the otters get established and feed in the reservoir doesn't mean that this structure is benefic to the species because the food supplied for it consists mainly of exotic fish species.

  5. Determination of Hg and diet identification in otter (Lontra longicaudis) feces

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    Ferreira Josef, Carla [Centro de Energia Nuclear na Agricultura - CENA-USP, Universidade de Sao Paulo, Av. Centenario 303, 13400-970 Piracicaba, Sao Paulo (Brazil)], E-mail: carlajosef@hotmail.com; Ramos Adriano, Leonardo; Franca, Elvis Joacir de; Gustinelli Arantes de Carvalho, Gabriel [Centro de Energia Nuclear na Agricultura - CENA-USP, Universidade de Sao Paulo, Av. Centenario 303, 13400-970 Piracicaba, Sao Paulo (Brazil); Ferreira, Jose Roberto [Centro de Energia Nuclear na Agricultura - CENA-USP, Universidade de Sao Paulo, Av. Centenario 303, 13400-970 Piracicaba, Sao Paulo (Brazil); Polo de Pesquisa e Desenvolvimento Regional do Centro Sul - APTA, Agencia Paulista de Tecnologia dos Agronegocios. Rua Alberto Coral 1500, 13400-000 Piracicaba, Sao Paulo (Brazil)

    2008-04-15

    An analytical procedure for the determination of Hg in otter (Lontra longicaudis) feces was developed, to separate fish scales for the identification of the animal diet. Samples were washed with ultra-pure water and the suspension was sampled and transferred for digestion. The solubilization was performed with nitric-perchloric acid mixture, and detection carried out by the atomic fluorescence spectrometry (AFS). The quality of the analytical procedure was assessed by analyzing in-house standard solutions and certified reference materials. Total Hg concentrations were in the range of 7.6-156 ng g{sup -1} (July 2004), 25.6-277 ng g{sup -1} (January 2005) and 14.6-744 ng g{sup -1} (May 2005) that is approximately the same order of magnitude for all samples collected in two reservoirs at the Tiete River, Brazil. Although Hg concentrations varied with sampling periods and diet, high levels were correlated to the percentage of carnivorous fish scales present in the otter feces. - The importance of otter feces preparation for Hg analysis, focusing the food web.

  6. Determination of Hg and diet identification in otter (Lontra longicaudis) feces

    International Nuclear Information System (INIS)

    Ferreira Josef, Carla; Ramos Adriano, Leonardo; Franca, Elvis Joacir de; Gustinelli Arantes de Carvalho, Gabriel; Ferreira, Jose Roberto

    2008-01-01

    An analytical procedure for the determination of Hg in otter (Lontra longicaudis) feces was developed, to separate fish scales for the identification of the animal diet. Samples were washed with ultra-pure water and the suspension was sampled and transferred for digestion. The solubilization was performed with nitric-perchloric acid mixture, and detection carried out by the atomic fluorescence spectrometry (AFS). The quality of the analytical procedure was assessed by analyzing in-house standard solutions and certified reference materials. Total Hg concentrations were in the range of 7.6-156 ng g -1 (July 2004), 25.6-277 ng g -1 (January 2005) and 14.6-744 ng g -1 (May 2005) that is approximately the same order of magnitude for all samples collected in two reservoirs at the Tiete River, Brazil. Although Hg concentrations varied with sampling periods and diet, high levels were correlated to the percentage of carnivorous fish scales present in the otter feces. - The importance of otter feces preparation for Hg analysis, focusing the food web

  7. Trophic ecology of Lontra longicaudis (Carnivora, Mustelidae in lotic and semilotic environments in southeastern Brazil Ecologia trófica de Lontra longicaudis (Carnivora, Mustelidae em ambientes lótico e semilótico no sudeste do Brasil

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    Lívia B. Santos

    2012-09-01

    Full Text Available Lontra longicaudis (Olfers, 1818 (Carnivora, Mustelidae is a semi-aquatic animal spread through the Central and South America, except in Chile. The implantation of a hydroelectric power plant along a river alters the dynamics of the watercourse, transforming a lotic environment into a lentic or semilotic one, what can damage the otter's feeding. From April 2008 to March 2009 we analysed the otter's food habits in lotic (streamlet and semilotic (hydroelectric reservoir environments of Paranapanema Valley, in southeastern Brazil. Aiming to compare the otter's diet of these two environments, we analyzed statistically the frequency of occurrence of main items in the scats. Fishes represent the base of the diet both in the reservoir and in the streamlet and, despite of the total otter's diet showing up similarities in the two environments, the results evidenced modifications on the fish species consumed between them. In the reservoir the otters ate more exotic fish Oreochromis niloticus (Linnaeus, 1758 probably because it is an easy capture prey in this place. The fact that the otters get established and feed in the reservoir doesn't mean that this structure is benefic to the species because the food supplied for it consists mainly of exotic fish species.Lontra longicaudis (Olfers, 1818 (Carnivora: Mustelidae é um animal semi-aquático com distribuição nas Américas Central e do Sul, exceto no Chile. A implantação de uma usina hidrelétrica em um rio altera a dinâmica do curso d'água, transformando um ambiente lótico em um lêntico ou semilótico, o que pode prejudicar a alimentação das lontras. De abril de 2008 a março de 2009 foi analisado o hábito alimentar das lontras em um ambiente lótico (riacho e semilótico (reservatório hidrelétrico no Vale do Paranapanema, sudeste do Brasil. Visando comparar a dieta das lontras nessas duas áreas analisamos estatisticamente a frequência de ocorrência dos principais itens nas fezes. Peixes

  8. Diet of Lontra longicaudis (Olfers, 1818 (Carnivora: Mustelidae in three limnic systems in Southern Rio Grande do Sul State, Brazil

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    Fernando Marques Quintela

    2012-12-01

    Full Text Available The aim of the present work was to study the diet of Lontra longicaudis in three limnic systems (anthropogenic shallow lakes, pluvial channel and coastal stream in Rio Grande do Sul State coastal plain, southern Brazil. Fishes were the most consumed item in all the three systems, being Mugilidae the most representative family in the pluvial channel and coastal stream and Cichlidae in the shallow lakes. Other identified items were mollusks, insects, crustaceans, amphibians, reptiles, birds and mammals and vegetal fragments. The high frequency of birds in the shallow lakes was remarkable, considering the lower frequencies of this item in previous investigations on the species diet. There was a high frequency of swamp eels (Synbranchidae, Synbranchus marmoratus in the pluvial channel and shallow lakes, which were usually absent or found in low frequencies in previous studies.

  9. Treetop shelter of a neotropical river otter cub (Lontra longicaudis - Carnivora: Mustelidae in an Amazonian flooded forest Abrigo em copa de árvore de filhote de lontra neotropical (Lontra longicaudis - Carnivora: Mustelidae em floresta inundável amazônica

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    Pedro Manuel Ribeiro Simões dos Santos

    2007-06-01

    Full Text Available The finding of a Neotropical river otter (Lontra longicaudis cub occupying a shelter in a hollowed treetop is reported. The observation was made in a seasonally flooded forest in Central Amazonia, during the high water peak of the annual inundation cycle. A literature review indicates that this is the first description of a shelter of the species, both in a hollowed tree and in Amazonia. This observation can indicate a strong relationship between the species' breeding cycle with the annual dynamics of Amazonian rivers. We discuss potential advantages and disadvantages of breeding when water level is high.É relatada a observação de um filhote de lontra (Lontra longicaudis ocupando um abrigo em uma cavidade na copa de uma árvore. A observação foi feita em uma floresta inundada na Amazônia Central, no pico de cheia do ciclo anual de inundação. A revisão da literatura revela que esta é a primeira descrição de um abrigo desta espécie em uma cavidade de árvore na natureza e na Amazônia. Tal observação pode indicar uma forte relação entre o ciclo reprodutivo da espécie e a dinâmica anual dos rios amazônicos. Discutimos vantagens e desvantagens potenciais da reprodução na época da cheia.

  10. Impacto de um desastre natural sobre o habitat e a ocorrência de Lontra longicaudis (Mustelidae, Carnivora na Serra da Prata, Paraná, Brasil

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    Marcos A. Navarro

    2017-10-01

    Full Text Available RESUMO Estudos com impacto de desastres naturais sobre a fauna são raros na literatura científica. Considerando Lontra longicaudis (Olfers, 1818, informações publicadas não foram encontradas. O presente estudo buscou determinar se os deslizamentos de terra ocorridos em março de 2011 em parte das montanhas da Serra da Prata (Paraná, Brasil afetaram de alguma forma a ocorrência da Lontra Neotropical no local impactado. Com esse propósito, a área estudada compreendeu um rio afetado (Rio Santa Cruz - RSC da face leste dessa serra que foi comparado com outro não afetado (Rio das Pombas - RP, localizado na mesma face da serra e com características semelhantes às originais do RSC. A área de estudo está situada no Parque Nacional de Saint-Hilaire/Lange (PNSHL. Foram realizadas sete campanhas a partir do limite altitudinal do PNSHL (60 m s.n.m para montante entre agosto de 2012 e julho de 2013. As campanhas consistiram de busca ativa por vestígios (fezes, pegadas, arranhados e tocas de lontras ao longo de 3 km de margens e leito. Registros de outros mamíferos também foram observados. Cada evidência foi anotada em caderneta de campo, fotografada e georreferenciada. As tocas foram monitoradas ao longo das campanhas. Considerando as lontras, foram registrados 102 vestígios (11 arranhados, 11 pegadas e 80 fezes e 17 tocas no rio não afetado (RP; e o rio afetado (RSC apresentou apenas quatro vestígios (três pegadas, uma amostra fecal e uma toca. Registros de outros mamíferos denotaram a presença de oito táxons no RP e 14 táxons no RSC. As diferenças conspícuas entre a quantidade de vestígios da presença das lontras indicam que o desastre natural afetou a população de lontras do RSC e mesmo dois anos após o evento as lontras retornaram apenas discretamente ao rio afetado. Por outro lado, outras espécies de mamíferos como Cuniculus paca (Linnaeus, 1758, reocuparam as margens abundantemente.

  11. Seasonal and spatial differences in feeding habits of the Neotropical otter Lontra longicaudis (Carnivora: Mustelidae in a coastal catchment of southeastern Brazil

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    Marcelo L Rheingantz

    2011-02-01

    Full Text Available The diet of the Neotropical otter Lontra longicaudis (Olfers, 1818 is one of the best known aspects of its biology throughout its distribution range. However, most dietary studies have been undertaken during short time periods, making it difficult to identify temporal patterns in the feeding behavior of the species. The present study aimed to describe the diet of L. longicaudis in the lower region of the Mambucaba Catchment, state of Rio de Janeiro, Brazil, during a three year period, based on analyses of spraints (feces. The results show fish as the main prey item (frequency of occurrence, FO = 85.78%, as already described in previous studies. Crustaceans were the second main prey (FO = 70.67%, occurring in the spraints during the whole year, however presenting a higher frequency of occurrence than fish in samples collected during some months. Anurans were the third most important prey item (FO = 9.56% and mammals, birds and reptiles were preyed upon only rarely (less than 4%. Fish and crustaceans were present in the diet of the species throughout the year and frogs were important mostly from June to August (dry season. This higher rate of predation on amphibians during the drier months was probably related to the decrease of the main prey.

  12. Diet of Lontra longicaudis (Carnivora: Mustelidae in a pool system in Atlantic Forest of Minas Gerais State, southeastern Brazil=Dieta de Lontra longicaudis (Carnivora: Mustelidae em um sistema de poções na Floresta Atlântica do Estado de Minas Gerais, sudeste do Brasil

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    Fernando Marques Quintela

    2012-10-01

    Full Text Available The present study aimed to investigate the feeding habits of Lontra longicaudis in a pool system within the Private Reserve of Natural Patrimony (RPPN Usina Maurício, located in Paraíba do Sul river basin, Atlantic Forest of southeastern Minas Gerais State. The diet composition was determined based on the identification of items present in 212 scats sampled between July 2008 and October 2009 in a 4.1 km stretch of the pool system. The found items and its respective percentages of occurrence were: mollusks (0.5%, insects (16.5%, spiders (1.4%, crustaceans (3.3%, fish (96.7%, amphibians (0.9%, snakes (3.8%, birds (2.8%, mammals (8.5% and fruits (0.5%. Among fish, the identified families and respective percentages of occurrence were: Loricariidae (65.4%, Pimelodidae (42.9% Cichlidae (22%, Characidae (7.3%, Erythrinidae (3.9%, Synbranchidae (2.4%, Anostomidae (2%. Therefore fish make up the most consumed item in the study area, with the predominance of benthic siluriformes (families Loricariidae and Pimelodidae. O presente estudo teve como objetivo investigar os hábitos alimentares de Lontra longicaudis em um sistema de poções na Reserva Particular do Patrimônio Natural – RPPN Usina Maurício, localizada na bacia do rio Paraíba do Sul, Mata Atlântica do Sudeste do Estado de Minas Gerais. A composição da dieta foi determinada com base na identificação de itens presentes em 212 amostras de fezes coletadas entre julho de 2008 e outubro de 2009 em um trecho de 4,1 km de um sistema de poções. Os itens alimentares encontrados e suas respectivas porcentagens de ocorrência foram: moluscos (0,5%, insetos (16,5%, aranhas (1,4%, crustáceos (3,3%, peixes (96,7%, anfíbios (0,9%, serpentes (3,8%, aves (2,8%, mamíferos (8,5%, frutos (0,5%. Dentre os peixes, famílias identificadas e suas respectivas porcentagens de ocorrência foram: Loricariidae (65,4%, Pimelodidae (42,9% Cichlidae (22%, Characidae (7,3%, Erythrinidae (3,9%, Synbranchidae (2

  13. Aspects of the biology of the African lungfish, Protopterus annectens ...

    African Journals Online (AJOL)

    Aspects of the biology of the African lungfish, Protopterus annectens (Owen, 1839) from Orashi and Sombreiro Rivers in Rivers State, Nigeria were investigated using routine biological approaches. Samples were collected between October 2012 and September 2013. The analysis of the stomach content showed that the ...

  14. Nicho trófico de la nutria neotropical (Lontra longicaudis en un ambiente modificado, Temascaltepec, México Food niche of the neotropical river otter (Lontra longicaudis in a modified environment, Temascaltepec, México

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    Octavio Monroy-Vilchis

    2009-12-01

    Full Text Available Se analizaron los cambios en espacio y tiempo de dieta de la nutria en Temascaltepec, Estado de México, en 2 ríos que presentan importante intervención humana causada por el establecimiento de criaderos de peces comerciales. Se recolectaron 157 excrementos, identificandose la trucha (Oncorhynchus mykiss como la presa más consumida (92.4%, seguida por invertebrados (3.5%, anfibios (2.9% y plantas (1.8%. La dieta de la nutria no varía significativamente entre estaciones climáticas, mientras que entre ríos, la variación fue significativa. En la zona de estudio, la nutria muestra tendencia a especializarse en el consumo de trucha. Las granjas de trucha influyen en la dieta de la nutria y se presentan como clave para la permanencia de la nutria en la zona de estudio.Spatial and temporal changes in the diet of the river otter in Temascaltepec, Mexico were analyzed on 2 rivers that present important human disturbance caused by aquaculture of commercial fish. 157 scats were collected, the principal prey was trout Oncorhynchus mykiss (92.4% followed by invertebrates (3.5%, amphibians (2.9% and plants (1.8%. Between climatic stations the diet of the river otter did not vary significantly, whereas between rivers it presented significant variation. The river otter showed specialization in the consumption of trout. The trout farms have influenced the diet of the river otter, and appear as key for the permanence of the otter in the study zone.

  15. Use of X-ray fluorescence energy dispersive technique in the lead determination and other metals in excrements of otters (Lontra longicaudis)

    International Nuclear Information System (INIS)

    Moraes, Liz Mary B.; Silva, Richard M.C.; Nascimento Filho, Virgilio F.; Ferreira, Carla Josef; Adriano, Leonardo R.; Ferreira, Jose Roberto

    2005-01-01

    This work had for objective to evaluate the contamination for Pb and other metals (Ti, Mn, Fe, Ni, Cu and Zn) in excrement samples of a neotropical otter population specie, found in river Betari, Alto Vale do Ribeira basin, Southeast Sao Paulo State. This river is a tributary of the Ribeira de Iguape river and part of its passage meets inside of the Parque Estadual Turistico do Alto Ribeira, one of the most conserved area of Brazilian Atlantic Forest. As the diet of these animals is based in fishes, it is an environmental interest in the determination of Pb in its excrements, since that is accumulating on the tropical chain path and in this region (in the decade of 1970) had the implanted a Pb extraction from galena mining. The analysis of the samples requires frequently the chemical digestion, with the disadvantages of being weak and expense. Aiming at to eliminate these disadvantages, the objective of the work was to use the X-ray fluorescence energy dispersive technique (EDXRF), for demanding a minimum preparation of the sample. Six excrement samples had been frozen, lyophilized and cryogenically milled, and after analyzed as pellet form, using a X-ray tube (target Mo, Zr filter, 25 kV/10 mA) and Si(Li) semiconductor spectrometer. The concentration was varied from 5.0 to 15.4 μg g -1 and it was possible also quantified other metals, showing maximum concentrations: Ti - 308, Mn - 38, Fe - 1131, Ni - 44, Cu . 2.8 and Zn . 92.4 μg g -1 . (author)

  16. Geology and mineral occurences of braquiantidinal do Lontra - GO

    International Nuclear Information System (INIS)

    Macambira, J.B.

    1983-01-01

    This work involved the geological mapping (in the scale 1:60.000) of an area of 800 square kilometers in the nortwestern part of the state of Goias, near and east of the Araguaia river. Based on the stratigraphy, metamorphism, geochronology, magmatism and mineral deposits hypotheses on the geological evolution of the region are discussed. The area studied belongs to the Precambrian Araguaia Fold Belt. The oldest rocks identified are trondhjemitic gneisses and on these rocks was deposited a sedimentary sequence with minor volcanics of a geosynclinal type. The stratigraphic column of Abreu (1978) was adopted with minor modifications. The basement, of transamazonic age (2000 Ma), consists mostly of gneiss, migmatite, granite gneiss and amphibolite. The metasediments belongs to the lower unit (Estrondo Group) of the Supergroup Baixo Araguaia. The Estrondo Group, of brasilian age (600 Ma), consists in the area of the lowermost Morro do Campo Formation, mainly quartzite and amphibolite, which give the high relief of the brachyanticlines of Lontra and Ramal do Lontra.(author)

  17. Hearing of the African lungfish (Protopterus annectens) suggests underwater pressure detection and rudimentary aerial hearing in early tetrapods.

    Science.gov (United States)

    Christensen, Christian Bech; Christensen-Dalsgaard, Jakob; Madsen, Peter Teglberg

    2015-02-01

    In the transition from an aquatic to a terrestrial lifestyle, vertebrate auditory systems have undergone major changes while adapting to aerial hearing. Lungfish are the closest living relatives of tetrapods and their auditory system may therefore be a suitable model of the auditory systems of early tetrapods such as Acanthostega. Therefore, experimental studies on the hearing capabilities of lungfish may shed light on the possible hearing capabilities of early tetrapods and broaden our understanding of hearing across the water-to-land transition. Here, we tested the hypotheses that (i) lungfish are sensitive to underwater pressure using their lungs as pressure-to-particle motion transducers and (ii) lungfish can detect airborne sound. To do so, we used neurophysiological recordings to estimate the vibration and pressure sensitivity of African lungfish (Protopterus annectens) in both water and air. We show that lungfish detect underwater sound pressure via pressure-to-particle motion transduction by air volumes in their lungs. The morphology of lungfish shows no specialized connection between these air volumes and the inner ears, and so our results imply that air breathing may have enabled rudimentary pressure detection as early as the Devonian era. Additionally, we demonstrate that lungfish in spite of their atympanic middle ear can detect airborne sound through detection of sound-induced head vibrations. This strongly suggests that even vertebrates with no middle ear adaptations for aerial hearing, such as the first tetrapods, had rudimentary aerial hearing that may have led to the evolution of tympanic middle ears in recent tetrapods. © 2015. Published by The Company of Biologists Ltd.

  18. Surgical implantation of intra-abdominal radiotransmitters in marine otters (Lontra felina) in central Chile.

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    Soto-Azat, Claudio; Boher, Francisca; Fabry, Mauricio; Pascual, Paulo; Medina-Vogel, Gonzalo

    2008-10-01

    Six free-ranging marine otters (Lontra felina) were livetrapped on the central coast of Chile and implanted with specially designed radiotransmitters as part of a spatial ecology study. Marine otters frequent the rocky seashore, often squeezing their narrow bodies through cracks and crevices and grooming themselves on the rocks. They are also among the smallest of the otter species, weighing between 3.4 kg and 4.5 kg. For these reasons, the transmitter used was small, rectangular, and flat, measuring 3.5 x 3.2 x 1.0 cm. They were implanted using a ventral midline approach to minimize contact between the skin incision and sharp-edged rocks. Surgical incisions healed within 2 wk. The transmitters functioned well, but the duration varied from 62 days to 143 days instead of the 240 days predicted by the manufacturer. All six marine otters reestablished in their home ranges, and survey results suggest they survived well beyond the life of the transmitters.

  19. Bilateral uric acid nephrolithiasis and ureteral hypertrophy in a free-ranging river otter (Lontra canadensis)

    Science.gov (United States)

    Grove, Robert A.; Bildfell, Rob; Henny, Charles J.; Buhler, D.R.

    2003-01-01

    We report the first case of uric acid nephrolithiasis in a free-ranging river otter (Lontra canadensis). A 7 yr old male river otter collected from the Skagit River of western Washington (USA) had bilateral nephrolithiasis and severely enlarged ureters (one of 305 examined [0.33%]). The uroliths were 97% uric acid and 3% protein. Microscopic changes in the kidney were confined to expansion of renal calyces, minor loss of medullary tissue, and multifocal atrophy of the cortical tubules. No inflammation was observed in either kidney or the ureters. The ureters were enlarged due to marked hypertrophy of smooth muscle plus dilation of the lumen. Fusion of the major calyces into a single ureteral lumen was several cm distal to that of two adult male otters used as histopathologic control specimens. This case report is part of a large contaminant study of river otters collected from Oregon and Washington. It is important to understand diseases and lesions of the otter as part of our overall evaluation of this population.

  20. Distribution and observations on the population of marine otters Lontra felina(Molina 1782 in Peru

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    Manuel Apaza

    2013-06-01

    Full Text Available We analyzed the distribution of marine otter Lontra felinaon the Peruvian coast, from Punta Aguja (05°47'S to the boundary with Chile (18°21'S. We performed a comprehensive analysis of the literature on L. felinato elucidate a northern boundary of its geographic distribution, concluding that there is no solid evidence of a possible northern limit at 6°S. For the same reasons, the affirmation of a "historic distribution" to the Lobos de Tierra island was discarded. It is also presented information of 272 otters from 130 locations between the years 2000 and 2010. The distribution of these records no has spatial autocorrelation, suggesting a homogeneous distribution. Considering the morphostructure and geomorphology of the Peruvian coast we can see similarities with the division into three zones: north, central and south, the last two add all records of otters, which could provide habitat characteristics that, allow a continuous distribution of L. felina. Finally there is an increase in the number of otters in the Peruvian coast to compare the current values with those of 40 years ago, but we show the lack of traceability of the latest information. We suggest undertaking research linking abundances and densities of otters with the characterization and distribution of their habitats, and behavioral studies that reveal the processes or intrinsic characteristics of the species to move into its geographic range.

  1. NUEVO REGISTRO DE LA NUTRIA MARINA Lontra felina (MOLINA, 1782) AL NORTE DE SU DISTRIBUCIÓN ACTUAL

    OpenAIRE

    Alfaro-Shigueto, Joanna; University of Exeter, Penyrn, Cornwall, TR10 9EZ, United Kingdom.; Valqui, Juan; Centro de Ornitología y Biodiversidad (CORBIDI). Calle Santa Rita 105 Of. 202, Lima 33, Perú.; Mangel, Jeffrey C.; University of Exeter, Penyrn, Cornwall, TR10 9EZ, United Kingdom.

    2011-01-01

    La nutria marina Lontra felina es una especie en peligro de extinción cuyo rango de distribución es controversial, siendo considerada el área de Chimbote (9°10´S) como el límite norte de su distribución actual. Aquí se documenta por primera vez su presencia a 115 km al norte de Chimbote, en el puerto artesanal de Huanchaco (08°04´S). La discusión de esta nota científica busca promover la generación de investigaciones que esclarezcan tanto los factores que determinan la presencia de la nutria ...

  2. Molecular Characterization of Aquaporin 1 and Aquaporin 3 from the Gills of the African Lungfish, Protopterus annectens, and Changes in Their Branchial mRNA Expression Levels and Protein Abundance during Three Phases of Aestivation.

    Science.gov (United States)

    Chng, You R; Ong, Jasmine L Y; Ching, Biyun; Chen, Xiu L; Hiong, Kum C; Wong, Wai P; Chew, Shit F; Lam, Siew H; Ip, Yuen K

    2016-01-01

    African lungfishes can undergo long periods of aestivation on land during drought. During aestivation, lungfishes are confronted with desiccation and dehydration, and their gills become non-functional and covered with a thick layer of dried mucus. Aquaporins (Aqps) are a superfamily of integral membrane proteins which generally facilitate the permeation of water through plasma membranes. This study aimed to obtain the complete cDNA coding sequences of aqp1 and aqp3 from the gills of Protopterus annectens , and to determine their branchial mRNA and protein expression levels during the induction, maintenance and arousal phases of aestivation. Dendrogramic analyses of the deduced Aqp1 and Aqp3 amino acid sequences of P. annectens revealed their close relationships with those of Latimeria chalumnae and tetrapods. During the induction phase, there were significant decreases in the transcript levels of aqp1 and aqp3 in the gills of P. annectens , but the branchial Aqp1 and Aqp3 protein abundance remained unchanged. As changes in transcription might precede changes in translation, this could be regarded as an adaptive response to decrease the protein abundance of Aqp1 and Aqp3 in the subsequent maintenance phase of aestivation. As expected, the branchial transcript levels and protein abundance of aqp1 /Aqp1 and aqp3 /Aqp3 were significantly down-regulated during the maintenance phase, probably attributable to the shutdown of branchial functions and the cessation of volume regulation of branchial epithelial cells. Additionally, these changes could reduce the loss of water through branchial epithelial surfaces, supplementing the anti-desiccating property of the dried mucus. Upon arousal, it was essential for the lungfish to restore branchial functions. Indeed, the protein abundance of Aqp1 recovered partially, with complete recovery of mRNA expression level and protein abundance of Aqp3, in the gills of P. annectens after 3 days of arousal. These results provide insights

  3. Differential gene expression in the liver of the African lungfish, Protopterus annectens, after 6 months of aestivation in air or 1 day of arousal from 6 months of aestivation.

    Directory of Open Access Journals (Sweden)

    Kum C Hiong

    Full Text Available The African lungfish, Protopterus annectens, can undergo aestivation during drought. Aestivation has three phases: induction, maintenance and arousal. The objective of this study was to examine the differential gene expression in the liver of P. annectens after 6 months (the maintenance phase of aestivation as compared with the freshwater control, or after 1 day of arousal from 6 months aestivation as compared with 6 months of aestivation using suppression subtractive hybridization. During the maintenance phase of aestivation, the mRNA expression of argininosuccinate synthetase 1 and carbamoyl phosphate synthetase III were up-regulated, indicating an increase in the ornithine-urea cycle capacity to detoxify ammonia to urea. There was also an increase in the expression of betaine homocysteine-S-transferase 1 which could reduce and prevent the accumulation of hepatic homocysteine. On the other hand, the down-regulation of superoxide dismutase 1 expression could signify a decrease in ROS production during the maintenance phase of aestivation. In addition, the maintenance phase was marked by decreases in expressions of genes related to blood coagulation, complement fixation and iron and copper metabolism, which could be strategies used to prevent thrombosis and to conserve energy. Unlike the maintenance phase of aestivation, there were increases in expressions of genes related to nitrogen, carbohydrate and lipid metabolism and fatty acid transport after 1 day of arousal from 6 months aestivation. There were also up-regulation in expressions of genes that were involved in the electron transport system and ATP synthesis, indicating a greater demand for metabolic energy during arousal. Overall, our results signify the importance of sustaining a low rate of waste production and conservation of energy store during the maintenance phase, and the dependence on internal energy store for repair and structural modification during the arousal phase, of

  4. Polychlorinated biphenyls, organochlorinated pesticides, and polybrominated diphenyl ethers in the cerebral cortex of wild river otters (Lontra canadensis)

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Niladri [National Wildlife Research Center, Canadian Wildlife Service, Environment Canada, Ottawa, Ontario, K1A 0H3 (Canada)]. E-mail: nbasu@uottawa.ca; Scheuhammer, Anton M. [National Wildlife Research Center, Canadian Wildlife Service, Environment Canada, Ottawa, Ontario, K1A 0H3 (Canada); O' Brien, Mike [Furbearers and Upland Game, Nova Scotia Department of Natural Resources, Kentville, Nova Scotia, B4N 4E5 (Canada)

    2007-09-15

    We measured the levels of ortho-substituted polychlorinated biphenyls (PCB), organochlorinated pesticides (OCP), and polybrominated diphenyl ethers (PBDE) in the cerebral cortex of river otters (Lontra canadensis) trapped from Ontario and Nova Scotia between 2002 and 2004. The mean concentration of total PCBs was 70.9 {+-} 12.1 ng/g l.w., and congeners 153, 180 and 138 accounted for nearly 60% of the sum. The mean concentration of total OCPs was 21.2 {+-} 3.7 ng/g l.w., and hexachlorobenzene (32.6% of total) and DDE (28.1%) accounted for the majority. The mean concentration of total PBDEs was 3.2 {+-} 0.6 ng/g l.w., and congeners 99 (44.9%), 153 (30.5%), and 100 (24.7%) were measured at the indicated percentages. There was no relationship between these residue data and concentrations of brain mercury or neurochemical receptors and enzymes as determined in earlier studies on these same animals. - River otters accumulated PCBs, OCPs, and PBDEs, but at levels below thresholds for neurotoxic effects.

  5. Polychlorinated biphenyls, organochlorinated pesticides, and polybrominated diphenyl ethers in the cerebral cortex of wild river otters (Lontra canadensis)

    International Nuclear Information System (INIS)

    Basu, Niladri; Scheuhammer, Anton M.; O'Brien, Mike

    2007-01-01

    We measured the levels of ortho-substituted polychlorinated biphenyls (PCB), organochlorinated pesticides (OCP), and polybrominated diphenyl ethers (PBDE) in the cerebral cortex of river otters (Lontra canadensis) trapped from Ontario and Nova Scotia between 2002 and 2004. The mean concentration of total PCBs was 70.9 ± 12.1 ng/g l.w., and congeners 153, 180 and 138 accounted for nearly 60% of the sum. The mean concentration of total OCPs was 21.2 ± 3.7 ng/g l.w., and hexachlorobenzene (32.6% of total) and DDE (28.1%) accounted for the majority. The mean concentration of total PBDEs was 3.2 ± 0.6 ng/g l.w., and congeners 99 (44.9%), 153 (30.5%), and 100 (24.7%) were measured at the indicated percentages. There was no relationship between these residue data and concentrations of brain mercury or neurochemical receptors and enzymes as determined in earlier studies on these same animals. - River otters accumulated PCBs, OCPs, and PBDEs, but at levels below thresholds for neurotoxic effects

  6. Phylogeography of the Patagonian otter Lontra provocax: adaptive divergence to marine habitat or signature of southern glacial refugia?

    Directory of Open Access Journals (Sweden)

    Chehébar Claudio

    2011-02-01

    Full Text Available Abstract Background A number of studies have described the extension of ice cover in western Patagonia during the Last Glacial Maximum, providing evidence of a complete cover of terrestrial habitat from 41°S to 56°S and two main refugia, one in south-eastern Tierra del Fuego and the other north of the Chiloé Island. However, recent evidence of high genetic diversity in Patagonian river species suggests the existence of aquatic refugia in this region. Here, we further test this hypothesis based on phylogeographic inferences from a semi-aquatic species that is a top predator of river and marine fauna, the huillín or Southern river otter (Lontra provocax. Results We examined mtDNA sequences of the control region, ND5 and Cytochrome-b (2151 bp in total in 75 samples of L. provocax from 21 locations in river and marine habitats. Phylogenetic analysis illustrates two main divergent clades for L. provocax in continental freshwater habitat. A highly diverse clade was represented by haplotypes from the marine habitat of the Southern Fjords and Channels (SFC region (43°38' to 53°08'S, whereas only one of these haplotypes was paraphyletic and associated with northern river haplotypes. Conclusions Our data support the hypothesis of the persistence of L. provocax in western Patagonia, south of the ice sheet limit, during last glacial maximum (41°S latitude. This limit also corresponds to a strong environmental change, which might have spurred L. provocax differentiation between the two environments.

  7. Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: Relationship to age and parasitism

    Energy Technology Data Exchange (ETDEWEB)

    Klenavic, Katherine [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada); Champoux, Louise [Service Canadien de la Faune Environnement Canada, 1141 Route de l' Eglise, c.p. 10100, Sainte-Foy, QC G1V 4H5 (Canada)], E-mail: louise.champoux@ec.gc.ca; Mike, O' Brien [Furbearers and Upland Game, Department of Natural Resources, Kentville, NS B4N 4E5 (Canada)], E-mail: obrienms@gov.ns.ca; Daoust, Pierre-Y. [Department of Pathology and Microbiology, Atlantic Veterinary College, University of P.E.I., 550 University Avenue, Charlottetown, PEI C1A 4P3 (Canada)], E-mail: daoust@upei.ca; Evans, R. Douglas [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada); Evans, Hayla E. [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada)], E-mail: hevans@trentu.ca

    2008-11-15

    Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink. - Mercury (Hg) concentrations in liver, brain and fur are correlated in mink (Mustela vison) and otters (Lontra canadensis), allowing the use of fur as an indicator of internal tissue concentrations.

  8. Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: Relationship to age and parasitism

    International Nuclear Information System (INIS)

    Klenavic, Katherine; Champoux, Louise; Mike, O'Brien; Daoust, Pierre-Y.; Evans, R. Douglas; Evans, Hayla E.

    2008-01-01

    Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink. - Mercury (Hg) concentrations in liver, brain and fur are correlated in mink (Mustela vison) and otters (Lontra canadensis), allowing the use of fur as an indicator of internal tissue concentrations

  9. Molecular characterization of three Rhesus glycoproteins from the gills of the African lungfish, Protopterus annectens, and effects of aestivation on their mRNA expression levels and protein abundance.

    Directory of Open Access Journals (Sweden)

    You R Chng

    Full Text Available African lungfishes are ammonotelic in water. They can aestivate for long periods on land during drought. During aestivation, the gills are covered with dried mucus and ammonia excretion ceases. In fishes, ammonia excretion through the gills involves Rhesus glycoproteins (RhGP/Rhgp. This study aimed to obtain the complete cDNA coding sequences of rhgp from the gills of Protopterus annectens, and to determine their branchial mRNA and protein expression levels during the induction, maintenance and arousal phases of aestivation. Three isoforms of rhgp (rhag, rhbg and rhcg were obtained in the gills of P. annectens. Their complete cDNA coding sequences ranged between 1311 and 1398 bp, coding for 436 to 465 amino acids with estimated molecular masses between 46.8 and 50.9 kDa. Dendrogramic analyses indicated that Rhag was grouped closer to fishes, while Rhbg and Rhcg were grouped closer to tetrapods. During the induction phase, the protein abundance of Rhag, but not its transcript level, was down-regulated in the gills, suggesting that there could be a decrease in the release of ammonia from the erythrocytes to the plasma. Furthermore, the branchial transcript levels of rhbg and rhcg decreased significantly, in preparation for the subsequent shutdown of gill functions. During the maintenance phase, the branchial expression levels of rhag/Rhag, rhbg/Rhbg and rhcg/Rhcg decreased significantly, indicating that their transcription and translation were down-regulated. This could be part of an overall mechanism to shut down branchial functions and save metabolic energy used for transcription and translation. It could also be regarded as an adaptive response to stop ammonia excretion. During the arousal phase, it is essential for the lungfish to regain the ability to excrete ammonia. Indeed, the protein abundance of Rhag, Rhbg and Rhcg recovered to the corresponding control levels after 1 day or 3 days of recovery from 6 months of aestivation.

  10. Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: relationship to age and parasitism.

    Science.gov (United States)

    Klenavic, Katherine; Champoux, Louise; Mike, O'Brien; Daoust, Pierre-Y; Evans, R Douglas; Evans, Hayla E

    2008-11-01

    Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink.

  11. Modeling Behavior by Coastal River Otter (Lontra Canadensis in Response to Prey Availability in Prince William Sound, Alaska: A Spatially-Explicit Individual-Based Approach.

    Directory of Open Access Journals (Sweden)

    Shannon E Albeke

    Full Text Available Effects of climate change on animal behavior and cascading ecosystem responses are rarely evaluated. In coastal Alaska, social river otters (Lontra Canadensis, largely males, cooperatively forage on schooling fish and use latrine sites to communicate group associations and dominance. Conversely, solitary otters, mainly females, feed on intertidal-demersal fish and display mutual avoidance via scent marking. This behavioral variability creates "hotspots" of nutrient deposition and affects plant productivity and diversity on the terrestrial landscape. Because the abundance of schooling pelagic fish is predicted to decline with climate change, we developed a spatially-explicit individual-based model (IBM of otter behavior and tested six scenarios based on potential shifts to distribution patterns of schooling fish. Emergent patterns from the IBM closely mimicked observed otter behavior and landscape use in the absence of explicit rules of intraspecific attraction or repulsion. Model results were most sensitive to rules regarding spatial memory and activity state following an encounter with a fish school. With declining availability of schooling fish, the number of social groups and the time simulated otters spent in the company of conspecifics declined. Concurrently, model results suggested an elevation of defecation rate, a 25% increase in nitrogen transport to the terrestrial landscape, and significant changes to the spatial distribution of "hotspots" with declines in schooling fish availability. However, reductions in availability of schooling fish could lead to declines in otter density over time.

  12. El muestreo no invasivo de las nutrias neotropicales, una especie amenazada, revela altos niveles de dispersión en el sistema fluvial del Lacantún, en Chiapas, México

    OpenAIRE

    Ortega, J.; Navarrete, D.; Maldonado, J. E.

    2012-01-01

    Se investigaron patrones de dispersión genética, niveles de estructura poblacional genética, y desplazamientos de las nutrias neotropicales (Lontra longicaudis) mediante el screening de ocho microsatélites polimórficos tomados del DNA de muestras fecales, que fueron recogidas en el sistema hidrológico del río Lacantún de la Selva Lacandona, Chiapas, México. Se detectó un total de 34 genotipos únicos a lo largo de seis ríos, estudiándose el efecto de la estructura genética según el paisaje. Se...

  13. Análise Espacial e Temporal dos Dados de Precipitação das Estações de Entorno da Bacia do Ribeirão Concórdia, Lontras (SC Visando Sua Inserção no Contexto de Mudanças Climáticas

    Directory of Open Access Journals (Sweden)

    Gustavo Antonio Piazza

    Full Text Available Resumo Mudanças climáticas são cada vez mais evidentes no cenário atual, provocando alterações em processos físicos, químicos e biológicos. O aumento da precipitação, por exemplo, é uma consequência das mudanças do clima. Este estudo teve por objetivo analisar o comportamento tendencial de dados mensais e anuais, assim como os máximos, das estações de entorno da bacia do Ribeirão Concórdia no município de Lontras no estado de Santa Catarina. Foi analisada a normalidade dos dados utilizados, além de três testes de aferição de tendências; o da análise da linha de tendência, o teste Mann-Kendall e a técnica da DFA (Detrended Fluctuation Analysis, além de uma correlação com índices do clima global. Foram encontradas tendências positivas para grande parte das estações analisadas por ambos os métodos (16 de 20, com significância para 11 estações. Os dados de máxima precipitação diária no mês também apresentaram aumento. Por meio de métodos estatísticos simplificados não foi encontrada correlação entre os dados pluviométricos e os índices globais na área analisada.

  14. Zooarqueologia dos mamíferos aquáticos e semi-aquáticos da Ilha de Santa Catarina, sul do Brasil

    Directory of Open Access Journals (Sweden)

    Pedro Volkmer de Castilho

    2001-09-01

    Full Text Available This study analyzes the use of aquatic mammals by prehistoric societies of Santa Catarina Island, Southern Brazil. Samples from two archaeological sites were examined: Rio do Meio (RM and Porto do Rio Vermelho (SCPRV. Nine aquatic mammal species were found: a pinnipeds: Arctocephalus australis (Zimmerman, 1783 and A. tropicalis (Gray, 1872, and b cetaceans: Eubalaena australis (Desmoulins, 1822, Delphinus delphis Linnaeus, 1758, Stenella frontalis (Cuvier, 1829, Steno bredanensis (Lesson, 1828, Tursiops truncatus (Montagu, 1821, Pontoporia blainvillei (Gervais & d'Orbigny, 1844 and a non-identified rorqual from the genus Balaenoptera Lacépède, 1804. Three especies of semi-aquatic mammals were also recorded: Hydrochoerus hydrochaeris (Linnaeus, 1758, Tapirus terrestris (Linnaeus, 1758 and Lontra longicaudis (Olfers,1818. Both sites presented similar species diversity, although abundance was greater at the most recent site (RM. There were more samples from axial skeletons, but in genera the anatomical regions were homogeneously distributed among the identified taxa.

  15. Cryptosporidium spp. and Giardia sp. in aquatic mammals in northern and northeastern Brazil.

    Science.gov (United States)

    Borges, João Carlos; Lima, Danielle Dos; da Silva, Edson Moura; Moreira, André Lucas de Oliveira; Marmontel, Miriam; Carvalho, Vitor Luz; Amaral, Rodrigo de; Lazzarini, Stella Maris; Alves, Leucio Câmara

    2017-09-20

    Cryptosporidium and Giardia are protozoans that can infect humans and wild and domestic animals. Due to the growing importance of diseases caused by protozoan parasites in aquatic species, we aimed to evaluate the frequency of infection by Cryptosporidium spp. and Giardia sp. in aquatic and marine mammals in the northern and northeastern regions of Brazil. We collected 553 fecal samples from 15 species of wild-ranging and captive aquatic mammals in northern and northeastern Brazil. All samples were analyzed by the Kinyoun technique for identification of Cryptosporidium spp. oocysts. Giardia sp. cysts were identified by means of the centrifugal-flotation technique in zinc sulfate solution. Subsequently, all samples were submitted for direct immunofluorescence testing. The overall frequency of infection was 15.55% (86/553) for Cryptosporidium spp. and 9.04% (50/553) for Giardia sp. The presence of Cryptosporidium spp. was detected in samples from 5 species: neotropical river otter Lontra longicaudis (15.28%), giant otter Pteronura brasiliensis (41.66%), Guiana dolphin Sotalia guianensis (9.67%), Amazonian manatee Trichechus inunguis (16.03%), and Antillean manatee T. manatus (13.79%). Giardia sp. was identified in L. longicaudis (9.23%), P. brasiliensis (29.16%), pygmy sperm whale Kogia breviceps (100%), dwarf sperm whale K. sima (25%), S. guianensis (9.67%), T. inunguis (3.81%), and T. manatus (10.34%). This is the first report of Cryptosporidium spp. in L. longicaudis, P. brasiliensis, and S. guianensis, while the occurrence of Giardia sp., in addition to the 2 otter species, was also identified in manatees, thus extending the number of hosts susceptible to these parasitic agents.

  16. Hearing in the African lungfish (Protopterus annectens): pre-adaptation to pressure hearing in tetrapods?

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob; Brandt, Christian; Wilson, Maria

    2010-01-01

    Lungfishes are the closest living relatives of the tetrapods, and the ear of recent lungfishes resembles the tetrapod ear more than the ear of ray-finned fishes and is therefore of interest for understanding the evolution of hearing in the early tetrapods. The water-to-land transition resulted...... shows measurable vibrations above 100 Hz when stimulated by air-borne sound, but the ear is apparently insensitive at these frequencies, suggesting that the lungfish ear is neither adapted nor pre-adapted for aerial hearing. Thus, if the lungfish ear is a model of the ear of early tetrapods...

  17. Hearing of the African lungfish (Protopterus annectens) suggests underwater pressure detection and rudimentary aerial hearing in early tetrapods

    DEFF Research Database (Denmark)

    Christensen, Christian Bech; Christensen-Dalsgaard, Jakob; Madsen, Professor Peter Teglberg

    2015-01-01

    of early tetrapods such as Acanthostega. Therefore, experimental studies on the hearing capabilities of lungfish may shed light on the possible hearing capabilities of early tetrapods and broaden our understanding of hearing across the water-to-land transition. Here, we tested the hypotheses that (i......In the transition from an aquatic to a terrestrial lifestyle, vertebrate auditory systems have undergone major changes while adapting to aerial hearing. Lungfish are the closest living relatives of tetrapods and their auditory system may therefore be a suitable model of the auditory systems...... for aerial hearing, such as the first tetrapods, had rudimentary aerial hearing that may have led to the evolution of tympanic middle ears in recent tetrapods....

  18. Hearing of the African lungfish (Protopterus annectens) suggests underwater pressure detection and rudimentary aerial hearing in early tetrapods

    OpenAIRE

    Christensen, Christian Bech; Christensen-Dalsgaard, Jakob; Madsen, Peter Teglberg

    2015-01-01

    In the transition from an aquatic to a terrestrial lifestyle, vertebrate auditory systems have undergone major changes while adapting to aerial hearing. Lungfish are the closest living relatives of tetrapods and their auditory system may therefore be a suitable model of the auditory systems of early tetrapods such as Acanthostega. Therefore, experimental studies on the hearing capabilities of lungfish may shed light on the possible hearing capabilities of early tetrapods and broaden our under...

  19. Non–invasive sampling of endangered neotropical river otters reveals high levels of dispersion in the Lacantun River System of Chiapas, Mexico

    Directory of Open Access Journals (Sweden)

    Ortega, J.

    2012-01-01

    Full Text Available Patterns of genetic dispersion, levels of population genetic structure, and movement of the neotropical river otter (Lontra longicaudis were investigated by screening eight polymorphic microsatellites from DNA extracted from fecal samples, collected in a hydrologic system of the Lacandon rainforest in Chiapas, Mexico. A total of 34 unique genotypes were detected from our surveys along six different rivers, and the effect of landscape genetic structure was studied. We recovered 16 of the 34 individuals in multiple rivers at multiple times. We found high levels of dispersion and low levels of genetic differentiation among otters from the six surveyed rivers (P > 0.05, except for the pairwise comparison among the Lacantún and José rivers (P < 0.05. We recommend that conservation management plans for the species consider the entire Lacantún River System and its tributaries as a single management unit to ensure the maintenance of current levels of population genetic diversity, because the population analyzed seems to follow a source–sink dynamic mainly determined by the existence of the major river.

  20. Discovery of the fossil otter Enhydritherium terraenovae (Carnivora, Mammalia) in Mexico reconciles a palaeozoogeographic mystery.

    Science.gov (United States)

    Tseng, Z Jack; Pacheco-Castro, Adolfo; Carranza-Castañeda, Oscar; Aranda-Gómez, José Jorge; Wang, Xiaoming; Troncoso, Hilda

    2017-06-01

    The North American fossil otter Enhydritherium terraenovae is thought to be partially convergent in ecological niche with the living sea otter Enhydra lutris , both having low-crowned crushing teeth and a close association with marine environments. Fossil records of Enhydritherium are found in mostly marginal marine deposits in California and Florida; despite presence of very rich records of fossil terrestrial mammals in contemporaneous localities inland, no Enhydritherium fossils are hitherto known in interior North America. Here we report the first occurrence of Enhydritherium outside of Florida and California, in a land-locked terrestrial mammal fauna of the upper Miocene deposits of Juchipila Basin, Zacatecas State, Mexico. This new occurrence of Enhydritherium is at least 200 km from the modern Pacific coastline, and nearly 600 km from the Gulf of Mexico. Besides providing further evidence that Enhydritherium was not dependent on coastal marine environments as originally interpreted, this discovery leads us to propose a new east-to-west dispersal route between the Florida and California Enhydritherium populations through central Mexico. The proximity of the fossil locality to nearby populations of modern neotropical otters Lontra longicaudis suggests that trans-Mexican freshwater corridors for vertebrate species in riparian habitats may have persisted for a prolonged period of time, pre-dating the Great American Biotic Interchange. © 2017 The Author(s).

  1. Ticks (Acari: Ixodida) on wild carnivores in Brazil.

    Science.gov (United States)

    Labruna, Marcelo B; Jorge, Rodrigo S P; Sana, Dênis A; Jácomo, Anah Tereza A; Kashivakura, Cyntia K; Furtado, Mariana M; Ferro, Claudia; Perez, Samuel A; Silveira, Leandro; Santos, Tarcísio S; Marques, Samuel R; Morato, Ronaldo G; Nava, Alessandra; Adania, Cristina H; Teixeira, Rodrigo H F; Gomes, Albério A B; Conforti, Valéria A; Azevedo, Fernando C C; Prada, Cristiana S; Silva, Jean C R; Batista, Adriana F; Marvulo, Maria Fernanda V; Morato, Rose L G; Alho, Cleber J R; Pinter, Adriano; Ferreira, Patrícia M; Ferreira, Fernado; Barros-Battesti, Darci M

    2005-01-01

    The present study reports field data of ticks infesting wild carnivores captured from July 1998 to September 2004 in Brazil. Additional data were obtained from one tick collection and from previous published data of ticks on carnivores in Brazil. During field work, a total of 3437 ticks were collected from 89 Cerdocyon thous (crab-eating fox), 58 Chrysocyon brachyurus (maned wolf), 30 Puma concolor (puma), 26 Panthera onca (jaguar), 12 Procyon cancrivorus (crab-eating raccoon), 4 Speothos venaticus (bush dog), 6 Pseudalopex vetulus (hoary fox), 6 Nasua nasua (coati), 6 Leopardus pardalis (ocelot), 2 Leopardus tigrinus (oncilla), 1 Leopardus wiedii (margay), 1 Herpailurus yagouaroundi (jaguarundi), 1 Oncifelis colocolo (pampas cat), 1 Eira barbara (tayara), 1 Galictis vittata (grison), 1 Lontra longicaudis (neotropical otter), and 1 Potus flavus (kinkajou). Data obtained from the Acari Collection IBSP included a total of 381 tick specimens collected on 13 C. thous, 8 C. brachyurus, 3 P. concolor, 10 P. onca, 3 P. cancrivorus, 4 N. nasua, 1 L. pardalis, 1 L. wiedii, 4 H. yagouaroundi, 1 Galictis cuja (lesser grison), and 1 L. longicaudis. The only tick-infested carnivore species previously reported in Brazil, for which we do not present any field data are Pseudalopex gymnocercus (pampas fox), Conepatus chinga (Molina's hog-nosed skunk), and Conepatus semistriatus (striped hog-nosed skunk). We report the first tick records in Brazil on two Felidae species (O. colocolo, H. yagouaroundi), two Canidae species (P. vetulus, S. venaticus), one Procyonidae species (P. flavus) and one Mustelidae (E. barbara). Tick infestation remains unreported for 5 of the 26 Carnivora species native in Brazil: Oncifelis geoffroyi (Geoffroy's cat), Atelocynus microtis (short-eared dog), Pteronura brasiliensis (giant otter), Mustela africana (Amazon weasel), and Bassaricyon gabbii (olingo). Our field data comprise 16 tick species represented by the genera Amblyomma (12 species), Ixodes (1

  2. Foraminiferal evidences for 77-year cycles of droughts in India and its possible modulation by the gleissberg solar cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; Khare, N.; Nair, R.R.

    proloculus size of Rotalidium annectens (Parker and Jones), is inversely proportional to salinity and an abundance of indicator species R. annectens is directly proportional to salinity. These parameters show considerable fluctuations in the core...

  3. Mamíferos carnívoros e sua relação com a diversidade de hábitats no Parque Nacional dos Aparados da Serra, sul do Brasil Carnivore mammals and their relation with habitat diversity in Aparados da Serra National Park, southern Brazil

    Directory of Open Access Journals (Sweden)

    Maria de Fátima M. dos Santos

    2004-09-01

    Full Text Available A survey of carnivore mammals was accomplished in Aparados da Serra National Park from February 1998 to March 2000. The park has 10,250 ha and is considered a biodiversity core area of the Atlantic Forest Biosphere Reserve in the Rio Grande do Sul State, Brazil. The landscape is characterized by relatively well preserved relicts of Araucaria angustifolia (Bertol. Kuntze forest, grasslands and Atlantic Forest, which have contributed for the survival of endangered carnivore mammals. The National Park was divided in a grid of 16 km² cells using a 1:50,000 scale map. The animals were recorded using indirect methods, by identifying signs (scats, tracks and direct observation in 2.5 km long and 5 m wide transects, with 10 replicates in each grid cell. Interviews with local people were also used to confirm the animal presence. A total of 13 species was recorded: Procyon cancrivorus (Cuvier, 1798, Pseudalopex gymnocercus (G. Fischer, 1814, Leopardus pardalis (Linnaeus, 1758 and Cerdocyon thous (Linnaeus, 1766 were the most frequent species registered. Nasua nasua (Linnaeus 1766, Herpailurus yaguarondi (Lacépède, 1809, Chrysocyon brachyurus (Illiger, 1815, Eira barbara (Linnaeus, 1758, Leopardus sp., Puma concolor (Linnaeus, 1771, Galictis cuja (Molina, 1782, Conepatus chinga (Molina, 1892 and Lontra longicaudis (Olfers, 1818 showed lower frequencies. The Park presented areas with significant differences (Mantel Test, P< 0.05 in species richness and composition related to habitat classes. Areas with high habitat richness presented high species richness. The Araucaria forest was the habitat that presented the higher carnivore richness. The border areas of the Park are influenced by several environmental degradation factors that could be affecting the distribution of carnivores.

  4. Trophic interactions of the endangered Southern river otter ( Lontra provocax) in a Chilean Ramsar wetland inferred from prey sampling, fecal analysis, and stable isotopes

    Science.gov (United States)

    Franco, Marcela; Guevara, Giovany; Correa, Loreto; Soto-Gamboa, Mauricio

    2013-04-01

    Non-invasive methodological approaches are highly recommended and commonly used to study the feeding ecology of elusive and threatened mammals. In this study, we use multiple lines of evidence to assess the feeding strategies of the endangered Southern river otter, by determining seasonal prey availability (electrofishing), analysis of undigested prey remains (spraints), and the use of stable isotopes (δ15N and δ13C) in otter spraints ( n = 262) and prey in a wetland ecosystem of southern Chile (39°49'S, 73°15'W). Fecal and isotopic analyses suggest that the otter diet is restricted to a few prey items, particularly the less-mobile, bottom-living, and larger prey such as crayfish ( Samastacus spinifrons, 86.11 %) and crabs ( Aegla spp., 32.45 %), supplemented opportunistically by cyprinids ( Cyprinus carpio, 9.55 %) and catfish ( Diplomystes camposensis, 5.66 %). The results suggest that the river otter is highly specialized in bottom foraging. Isotopic signatures of food sources and feces revealed a mid-upper trophic position for the Southern river otter, with either higher or lower δ15N values than their potential prey items. δ13C values for river otters were less enriched than their potential food resources. We suggest that due to their narrow trophic niche and possible dependence on only a few food items, this species may be highly vulnerable to the reduction in its prey populations. Finally, maintaining the ecological interactions between Southern river otters and their prey is considered a central priority for the survival of this endangered carnivore mammal.

  5. Diversidad,historia natural y conservación de los mamíferos de San Vito de Coto Brus, Costa Rica

    Directory of Open Access Journals (Sweden)

    Jesús Pacheco

    2006-03-01

    Full Text Available Aunque Costa Rica ha sido biológicamente bien estudiada, pocas áreas tiene inventarios de mamíferos completos y actualizados,lo que es para llevar a cabo estudios ecológicos y de conservación. La región de San Vito es considerada entre las mas importantes para la investigación científica en el país, debido a la presencia del Jardín Botánico Wilson y la Estación Biológica Las Cruces. Sin embargo, el conocimiento de la mastofauna es incompleto. Por lo tanto se evaluó intensamente los mamíferos de San Vito, y se compiló una lista de especies, con una evaluación de su composición, abundancia relativa, distribución en los habitats, y su estado de conservación. Se registraron 105 especies, que representaron a 85 géneros, 29 familias y 10 órdenes. Los mamíferos no voladores representaron 62 especies, 59 géneros, 23 familias y 9 órdenes. Los murciélagos pertenecieron a 6 familias, 26 géneros y 43 especies. La extensa deforestación y cacería son factores que han causado la extinción local de 7especies, pero la región todavía mantiene un número relativamente alto de su diversidad original, incluyendo a especie raras. Pocas especies fueron comunes o abundantes. La riqueza de especies fue alta en el bosque y los fragmentos de bosque, y más baja en las plantaciones de café, pastizales inducidos y vegetación secundaria. Alrededor del 21% (13 de las espcies estan incluidad en el libro rojo de la UICN. Tres especies (Saimiri oerstedii, Tapirus bairdii y Sylvilagus dicei son consideradas en peligro y dos (Myrmecophaga trydactila y Caluromys derbianus como amenazadas:de estas, dos especies (T. bairdii and M. trydactila se encuentran localmente extintas. Las otras especies son consideradas de bajo riesgo (i. e. Chironectes minimus o con poca información (i. e. Lontra longicaudis . Adicionalmente, 24 especies (39% están incluidas en CITES.Diversity, natural history and conservation of mammals from San Vito de Coto Brus, Costa

  6. Influence of estuaries on shelf foraminiferal species

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.

    Dabhol-bhatkal stretch of the west coast of India is marked by a number of estuaries. Cavarotalia annectens is selected to monitor the influence of these estuaries on the inner shelf foraminiferal fauna. The percentage distribution of this species...

  7. The intriguing relationship between coiling direction and reproductive mode in benthic foraminifera

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; Rao, A

    direction changes. The relationship between mode of reproduction and coiling directions in benthic foraminifera is explored. Benthic foraminiferal species Cavarotalia annectens (Paarker & Jones) in 58 samples obtained from a core off Karwar, west coast...

  8. Mean proloculus size, delta super(13) C and delta super(18) O variations in recent benthic foraminifera from the west coast of India and their climatic implications

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; Sarkar, A.

    The interrelationship between mean proloculus size (MPS), delta super(18) O and delta super(13) C vatiations in benthic foraminiferal species Rotalidium annectens and their relation with temperature (T) and salinity (S) have been studied in samples...

  9. Marine Mammals as Models for Cost Efficient AUVs: Specifications of Oscillating Hydrofoils

    National Research Council Canada - National Science Library

    Williams, Terrie

    2004-01-01

    ...), California sea lions (Zalophus californianus), river otters (Lontra canadensis), and sea otters (Enhydra lutris) to assess the mechanical operation and energetic cost of oscillating hydrofoils performing in controlled environments...

  10. Life Histories of Frogs in the Namib Desert | Channing | African ...

    African Journals Online (AJOL)

    Four anuran taxa inhabit the central Namib: Xenopus laevis, Tomopterna delalandei cryptotis, Phrynomerus annectens and Bufo vertebrate hoeschi. Xenopus is confined to permanent pools in the Kuiseb river canyon. Tomopterna extends further into the Namib, but is restricted to the Kuiseb river bed. The Kuiseb is normally ...

  11. Reproductive behaviour of benthic foraminifera: A key to palaeoclimate

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.

    in mean proloculus size in Cavarotalia annectens in a number of modern surface sediment samples from the inner shelf of the west coast of India. It is observed that mean proloculus size is inversely proportional to temperature and salinity. In view...

  12. Fluctuating monsoonal precipitation as revealed by foraminiferal variations in a core from shelf regime off Karwar (India)

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.

    in this area. The percentage abundance of C. annectens in the total benthic foraminifera obtained for each sample and plotted against depth in core varied from 0 to 4.88%. In coastal areas, abundance of this species is inversely proportional to freshwater...

  13. The species of Hemiancistrus (Siluriformes: Loricariidae) from Ecuador.

    Science.gov (United States)

    Provenzano R, Francisco; Barriga S, Ramiro

    2017-05-29

    At the Fish Collection of the Instituto de Ciencias Biológicas, Escuela Politécnica Nacional, Quito, three species traditionally grouped in the genus Hemiancistrus were identified: H. annectens (Regan 1904), H. landoni Eigenmann 1916, and a new specie described here. The new species inhabits exclusively in the Esmeraldas River Basin, Pacific slope, northwestern Ecuador. It is easily recognized by the completely naked abdomen, with rounded, dark spots, and a different color pattern on the dorsal and caudal fins. A comparative analysis of bones related to the opercular mobility, shows important differences between H. annectens, H. landoni, and the new species, suggesting that H. annectens does not belong to the genus Hemiancistrus or the Ancistrini group. According to the characteristics observed in these bones, H. annectens shows greater similarity to those reported in species of the Hypostomini group, supporting its inclusion in this group, but placing it in the genus Hypostomus requires further analysis. On the other hand, the conditions observed on the bones of Hemiancistrus landoni and the new species suggest that both are inside of the Ancistrini group. The new species is placed in the genus Hemiancistrus tentatively, pending future analysis.

  14. The Effect Of Salinity Stress On Buccal Ventilatory Rate In The ...

    African Journals Online (AJOL)

    The Effect Of Salinity Stress On Buccal Ventilatory Rate In The African Lungfish, Protopterus annectens Owen. AI Okafor, LO Chukwu, LO Chukwu. Abstract. No Abstract. Animal Research International Vol. 2 (1) 2005 pp. 252-254. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...

  15. An eDNA assay for river otter detection: A tool for surveying a semi-aquatic mammal

    Science.gov (United States)

    Ticha M. Padgett-Stewart; Taylor M. Wilcox; Kellie J. Carim; Kevin S. McKelvey; Michael K. Young; Michael K. Schwartz

    2016-01-01

    Environmental DNA (eDNA) is an effective tool for the detection of elusive or low-density aquatic organisms. However, it has infrequently been applied to mammalian species. North American river otters (Lontra canadensis) are both broad ranging and semi-aquatic, making them an ideal candidate for examining the uses of eDNA for detection of mammals. We developed...

  16. Water infiltration capacity under different land uses and agricultural management practices

    OpenAIRE

    Lizandra Poeta Teixeira; Vander Kaufmann; Adilson Pinheiro

    2009-01-01

    Knowledge of physical and hydraulic properties of soil is important for the appropriate use and management of soil, and for the understanding of dynamic movement process of water and solutes. This study aims to determine the soil infiltration capacity of the Concordia Experimental Basin, located in the municipality of Lontras in Santa Catarina state. The infiltration tests were performed with the concentric ring infiltrometer, with a diameter of 25 and 50 cm on twenty sampling points showing ...

  17. Habitat quality assessment for the Eurasian otter (Lutra lutra on the river Jajrood, Iran

    Directory of Open Access Journals (Sweden)

    Roohallah Mirzaei

    2010-06-01

    Full Text Available Abstract There is little information about the status and ecology of the Eurasian otter (Lutra lutra in Iran. We assessed the habitat suitability for otters of the River Jajrood, Tehran province, measuring, or visually estimating, 12 environmental parameters along 16 600 m long river stretches (sampling sites. The downstream stretches of the river were found to be more suitable for otters with respect to the upper part of its course. Although the assessments of habitat suitability for the otter may be affected by several limits, the current distribution of the species on the river agrees with the results of this study. The preservation of the otter in Tehran province should involve the restoration of the ecosystem of the River Jajrood in order to improve the length of suitable river stretches.
    Riassunto Stima dell’idoneità ambientale per la lontra (Lutra lutra del fiume Jajrood, Iran. Le informazioni relative alla lontra (Lutra lutra in Iran sono scarse. L’idoneità ambientale per la specie del fiume Jajrood, provincia di Tehran, è stata valutata, misurando o stimando 12 parametri ambientali lungo 16 stazioni di campionamento, coincidenti con tratti di fiume della lunghezza di 600 m. I tratti più a valle sono risultati più idonei rispetto al corso superiore del fiume. Malgrado i numerosi limiti del metodo di stima dell’idoneità ambientale adottato, i risultati sono in accordo con l’attuale distribuzione della lontra lungo il fiume Jajrood. La conservazione della lontra nella provincia di Tehran dovrebbe prevedere miglioramenti ambientali volti a incrementare lo sviluppo lineare degli habitat idonei lungo il fiume Jajrood.

    doi:10.4404/hystrix-20.2-4447

  18. Habitat networking: a new chance for the otter in Europe?

    Directory of Open Access Journals (Sweden)

    Claus Reuther

    1995-12-01

    Full Text Available Abstract One of the main problems for otter protection in Germany as well as in Europe is the fragmentation and isolation of populations. In Germany a thriving population exists in the eastern parts of the country while in the central parts only isolated populations remain, and in the western parts the species is extirpated. On the basis of this situation a habitat network program is in progress with the aim to protect and restore not only those habitats where the otter still remains but also those habitats which can function as a network to connect the thriving with the isolated populations. This network focuses on existing protected wetlands or rivers and restoration activities in wetlands or rivers. The situation of the otter in Europe (excluding Scandinavia and the British Isles is comparable to that in Germany. There are stable or thriving populations in the eastern and western parts while in Central Europe only isolated populations remain. Following the German otter habitat network program possibilities are shown and discussed to establish a habitat network program for the otter on a European level. Riassunto Ripristino di una rete di ambienti favorevoli alla lontra: una nuova possibilità per la specie in Europa? - Uno dei principali problemi riguardanti la conservazione della lontra (Lutra lutra in Germania, come del resto in Europa, è la frammentazione e l'isolamento delle popolazioni. In Germania, una cospicua popolazione esiste nella parte orientale, mentre in quella centrale sono presenti nuclei isolati; nella porzione occidentale del paese la specie è invece praticamente estinta. Tenendo presente questa situazione, è stato avviato un programma di ricostruzione di una rete di ambienti favorevoli alla lontra con l'obiettivo di proteggere e ripristinare non solo gli ambienti in cui la specie è attualmente presente, ma anche quelli che possono funzionare come rete di

  19. Habitat quality, water quality and otter distribution

    Directory of Open Access Journals (Sweden)

    Christopher Mason

    1995-12-01

    Full Text Available Abstract In recent decades the otter (Lutra lutra has declined over much of Europe. Good habitat has been shown to be essential to otters. Specific elements of cover have been identified in some studies but the minimum cover requirements to support otter populations are not known. These are likely to vary in relation to other factors, such as disturbance. Habitat destruction has been severe in many areas of Europe. Water quantity is important to otters, especially where low flows destroy the food base, namely fish. However the minimum food requirements to support populations are not known. The main cause of the decline in otter populations is almost certainly bioaccumulating pollutants, especially PCBs. These are likely to be inhibiting recolonization in many areas. In Britain, catchment distribution of otters within regions is negatively correlated to mean PCB levels in otter spraints, and these are indicative of tissue levels. PCBs have been found in all samples studied. Current EC statutory monitoring is inadequate to protect otter populations from bioaccumulating contaminants. Standards are presented here for otter protection. More fundamental research is required to refine our understanding of the requirements of the otter. Riassunto Qualità ambientale, qualità dell'acqua e distribuzione della lontra - Negli ultimi decenni la lontra (Lutra lutra è diminuita su buona parte del suo areale europeo, dove particolarmente pesante è stata la distruzione di ambienti favorevoli. Habitat qualitativamente idonei sono essenziali per la sopravvivenza della specie. In alcuni studi, specifici parametri di copertura vegetale dei corpi idrici sono stati ritenuti importanti per la specie, ma quale sia il valore minimo di copertura riparia in grado di supportare una popolazione resta sconosciuto. I parametri di copertura variano probabilmente in relazione ad altri fattori, quali, ad

  20. Foraging behaviour and feeding ecology of the otter Lutra lutra: a selective review

    Directory of Open Access Journals (Sweden)

    David Carss

    1995-12-01

    Full Text Available Abstract This paper reviews literature on food, foraging behaviour and feeding ecology of Lutra lutra and on the behaviour of their prey species. Otters have a diverse diet, forage in a wide variety of different habitats and have a relatively complex social system. Similarly, their strategies for obtaining food are complex and varied. Three aspects of foraging behaviour (i, ii, iii and two of feeding ecology (iv, v are discussed: i adaptations and ontogeny, ii energetics and food-limitation, iii human disturbance, and periods of prey vulnerability, iv assessing diet, and v changes in prey vulnerability and selection. The review has three main aims: (a to summarize some recent advances in research, (b to highlight gaps in current knowledge, and (c to suggest some areas of future research. The need for such a review arises from a necessity to direct further research effort towards carnivore predator-prey relationships in general, and those of otters in particular, and also to meet demands for conservation management. Riassunto Foraggiamento ed ecologia alimentare della lontra Lutra lutra: un'analisi selettiva della letteratura disponibile - Questo lavoro prende in esame la letteratura riguardante dieta, foraggiamento ed ecologia alimentare della lontra Lutra lutra e il comportamento delle sue prede. La lontra ha una dieta varia, ricerca il cibo in un'ampia gamma di ambienti e ha un'organizzazione sociale relativamentc complessa. Similarmente, le sue strategie di ricerca del cibo sono complesse e varie. Tre aspetti del foraggiamento (i, ii, iii e due di ecologia alimentare (iv, v sono qui discussi: i adattamenti e ontogenesi, ii richiesta energetica e fattori limitanti la disponibilità di cibo, iii disturbo antropico e periodi di vulnerabilità delle prede, iv analisi della dieta, e v cambiamenti nella vulnerabilità delle prede e selezione. Il presente lavoro ha tre

  1. Supplementary cranial description of the types of Edmontosaurus regalis (Ornithischia: Hadrosauridae, with comments on the phylogenetics and biogeography of Hadrosaurinae.

    Directory of Open Access Journals (Sweden)

    Hai Xing

    Full Text Available The cranial anatomy of the flat-skulled hadrosaurine Edmontosaurus regalis (Ornithischia: Hadrosauridae is extensively described here, based on the holotype and paratype collected from the middle part of the Horseshoe Canyon Formation in southern Alberta. Focus is given to previously undocumented features of ontogenetic and phylogenetic importance. This description facilitates overall osteological comparisons between E. regalis and other hadrosaurids (especially E. annectens, and revises the diagnosis of E. regalis, to which a new autapomorphy (the dorsal half of the jugal anterior process bearing a sharp posterolateral projection into the orbit is added. We consider the recently named Ugrunaaluk kuukpikensis from the upper Campanian/lower Maastrichtian of Alaska a nomen dubium, and conservatively regard the Alaskan material as belonging to Edmontosaurus sp.. A phylogenetic analysis of Hadrosauroidea using maximum parsimony further corroborates the sister-taxon relationship between E. regalis and E. annectens. In the strict consensus tree, Hadrosaurus foulkii occurs firmly within the clade comprising all non-lambeosaurine hadrosaurids, supporting the taxonomic scheme that divides Hadrosauridae into Hadrosaurinae and Lambeosaurinae. Within Edmontosaurini, Kerberosaurus is posited as the sister taxon to the clade of Shantungosaurus + Edmontosaurus. The biogeographic reconstruction of Hadrosaurinae in light of the time-calibrated cladogram and probability calculation of ancestral areas for all internal nodes reveals a significantly high probability for the North American origin of the clade. However, the Laramidia-Appalachia dispersals around the Santonian-Campanian boundary, inferred from the biogeographic scenario for the North American origin of Hadrosaurinae, are in conflict with currently accepted paleogeographic models. By contrast, the Asian origin of Hadrosaurinae with its relatively low probability resulting from the biogeographic analysis

  2. Supplementary cranial description of the types of Edmontosaurus regalis (Ornithischia: Hadrosauridae), with comments on the phylogenetics and biogeography of Hadrosaurinae.

    Science.gov (United States)

    Xing, Hai; Mallon, Jordan C; Currie, Margaret L

    2017-01-01

    The cranial anatomy of the flat-skulled hadrosaurine Edmontosaurus regalis (Ornithischia: Hadrosauridae) is extensively described here, based on the holotype and paratype collected from the middle part of the Horseshoe Canyon Formation in southern Alberta. Focus is given to previously undocumented features of ontogenetic and phylogenetic importance. This description facilitates overall osteological comparisons between E. regalis and other hadrosaurids (especially E. annectens), and revises the diagnosis of E. regalis, to which a new autapomorphy (the dorsal half of the jugal anterior process bearing a sharp posterolateral projection into the orbit) is added. We consider the recently named Ugrunaaluk kuukpikensis from the upper Campanian/lower Maastrichtian of Alaska a nomen dubium, and conservatively regard the Alaskan material as belonging to Edmontosaurus sp.. A phylogenetic analysis of Hadrosauroidea using maximum parsimony further corroborates the sister-taxon relationship between E. regalis and E. annectens. In the strict consensus tree, Hadrosaurus foulkii occurs firmly within the clade comprising all non-lambeosaurine hadrosaurids, supporting the taxonomic scheme that divides Hadrosauridae into Hadrosaurinae and Lambeosaurinae. Within Edmontosaurini, Kerberosaurus is posited as the sister taxon to the clade of Shantungosaurus + Edmontosaurus. The biogeographic reconstruction of Hadrosaurinae in light of the time-calibrated cladogram and probability calculation of ancestral areas for all internal nodes reveals a significantly high probability for the North American origin of the clade. However, the Laramidia-Appalachia dispersals around the Santonian-Campanian boundary, inferred from the biogeographic scenario for the North American origin of Hadrosaurinae, are in conflict with currently accepted paleogeographic models. By contrast, the Asian origin of Hadrosaurinae with its relatively low probability resulting from the biogeographic analysis is worth

  3. Proposals for the conservation of otters Lutra lutra L. on Corfu island (Ionian Sea, Greece

    Directory of Open Access Journals (Sweden)

    Xavier Grémillet

    1995-12-01

    Full Text Available Abstract Suggested measures for the conservation of otters (Lutra lutra on Corfu include: 1 a nature sanctuary ("Otter Haven" for some little remote lagoons near Aghios Stephanos in the north-east; 2 a lagoon restoration scheme including restoration of traditional fishing with joint nature tourism for the large reedbeds and lagoons: Antinioti (100 ha in the north, Chalkiopoulou (380 ha in the suburbs of Kerkyra, Korission (500 ha in the south-west; 3 the stopping of raw sewage discharge, illegal infilling, building and waste dumping in the wetlands; 4 the limitation of intensive fish farming schemes. Such a policy is reconcilable with economic activities (tourism, fishing, trade or administration. Riassunto Proposte per la conservazione della lontra Lutra lutra L. nell'isola di Corfù (Mare Jonio, Grecia - Per la conservazione della lontra (Lutra lutra nell'Isola di Corfù sono suggeriti i seguenti interventi: 1 creazione di "santuari naturali" per la specie comprendenti le piccole lagune vicino a Aghios Stephanos nella parte nord-est dell'isola; 2 riqualificazione degli ambienti a canneto e delle lagune, abbinata a1 ripristino della pesca tradizionale e allo sviluppo del turismo ecologico: Antinioti (100 ha nella parte settentrionale, Chalkiopoulou (380 ha nell'area suburbana di Kerkyra, Korission (500 ha nella parte sud-ovest; 3 divieto di scarichi fognari e abusivi, divieto di costruzione di insediamenti abitativi e eliminazione di discariche nelle zone umide; 4 limitazioni allo sviluppo degli allevamenti ittici intensivi. Gli interventi prospettati si inquadrano in una politica di gestione ambientale compatibile con le attività economiche presenti (turismo, pesca, commercio.

  4. A predictive model of the effect of environmental factors on the occurrence of otters (Lutra lutra L. in Hungary

    Directory of Open Access Journals (Sweden)

    Ildikó Kemenes

    1995-12-01

    useful tool to pinpoint sites of possible significance for the purposes of conservation of existing or potential otter habitats. Riassunto Modello predittivo dell'effetto dei fattori ambientali sulla presenza della Lontra (Lutra lutra L. in Ungheria - Un'indagine sulla distribuzione della lontra (Lutra lutra L. in Ungheria ha evidenziato che la specie è comune in buona parte del paese dove l'ambiente acquatico appare adatto. C'era comunque un largo numero di habitat apparentemente in buone condizioni dove la presenza della specie non era accertata. Al contrario, alcuni siti, che sulla base di una valutazione qualitativa sarebbero stati negativi per la lontra, rivelavano segni di presenza del mustelide. L'unico fattore che limitava fortemente la presenza della specie era l'elevato inquinamento chimico delle acque, come accertato dai dati raccolti dalle autorità competenti. Quanto sopra esposto ci ha portato all'impiego di un metodo quantitativo che tenesse conto delle variabili ambientali (3 valutate secondo una scala di punteggio e 5 sulla base della loro presenza/assenza che potevano influenzare la presenza della specie. Il modello di analisi utilizzato, chiamato regressione logistica, è utile per esaminare le relazioni tra una variabile dipendente binaria e un gruppo di variabili indipendenti espresse secondo categorie. Per 369 siti esaminati in diversi corpi idrici è stata accertata la presenza (valore 1 o l'assenza (valore 0 della lontra e sono state stimate le seguenti variabili: profondità dell'acqua, pendenza delle rive, copertura vegetale riparia e la presenza o assenza di vari fattori legati alle attività produttive, quali, ad esempio, l'uso agricolo dei terreni a ridosso delle rive dei corpi idrici e la presenza visibile di inquinamento. Le prime tre variabili erano valutate secondo una scala di punteggio, le altre invece avevano valore 1 quando presenti, 0 quando assenti (v. metodi. I risultati ottenuti

  5. Importance of terrestrial arthropods as subsidies in lowland Neotropical rain forest stream ecosystems

    Science.gov (United States)

    Small, Gaston E.; Torres, Pedro J.; Schwizer, Lauren M.; Duff, John H.; Pringle, Catherine M.

    2013-01-01

    The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an important subsidy to tropical stream food webs and could also represent an important flux of nitrogen (N) and phosphorus (P) in nutrient-poor headwater streams. We quantified input rates of terrestrial insects in eight streams draining lowland tropical wet forest in Costa Rica. In two focal headwater streams, we also measured capture efficiency by the fish assemblage and quantified terrestrially derived N- and P-excretion relative to stream nutrient uptake rates. Average input rates of terrestrial insects ranged from 5 to 41 mg dry mass/m2/d, exceeding previous measurements of aquatic invertebrate secondary production in these study streams, and were relatively consistent year-round, in contrast to values reported in temperate streams. Terrestrial insects accounted for half of the diet of the dominant fish species, Priapicthys annectens. Although terrestrially derived fish excretion was found to be a small flux relative to measured nutrient uptake rates in the focal streams, the efficient capture and processing of terrestrial arthropods by fish made these nutrients available to the local stream ecosystem. This aquatic-terrestrial linkage is likely being decoupled by deforestation in many tropical regions, with largely unknown but potentially important ecological consequences.

  6. Polypteridae (Actinopterygii: Cladistia) and DANA-SINEs insertions.

    Science.gov (United States)

    Morescalchi, Maria Alessandra; Barucca, Marco; Stingo, Vincenzo; Capriglione, Teresa

    2010-06-01

    SINE sequences are interspersed throughout virtually all eukaryotic genomes and greatly outnumber the other repetitive elements. These sequences are of increasing interest for phylogenetic studies because of their diagnostic power for establishing common ancestry among taxa, once properly characterized. We identified and characterized a peculiar family of composite tRNA-derived short interspersed SINEs, DANA-SINEs, associated with mutational activities in Danio rerio, in a group of species belonging to one of the most basal bony fish families, the Polypteridae, in order to investigate their own inner specific phylogenetic relationships. DANA sequences were identified, sequenced and then localized, by means of fluorescent in situ hybridization (FISH), in six Polypteridae species (Polypterus delhezi, P. ornatipinnis, P. palmas, P. buettikoferi P. senegalus and Erpetoichthys calabaricus) After cloning, the sequences obtained were aligned for phylogenetic analysis, comparing them with three Dipnoan lungfish species (Protopterus annectens, P. aethiopicus, Lepidosiren paradoxa), and Lethenteron reissneri (Petromyzontidae)was used as outgroup. The obtained overlapping MP, ML and NJ tree clustered together the species belonging to the two taxonomically different Osteichthyans groups: the Polypteridae, by one side, and the Protopteridae by the other, with the monotypic genus Erpetoichthys more distantly related to the Polypterus genus comprising three distinct groups: P. palmas and P. buettikoferi, P. delhezi and P. ornatipinnis and P. senegalus. In situ hybridization with DANA probes marked along the whole chromosome arms in the metaphases of all the Polypteridae species examined. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Otter Lutra lutra movements assessed by genotyped spraints in southern Italy

    Directory of Open Access Journals (Sweden)

    Claudio Prigioni

    2006-09-01

    Full Text Available Abstract
    This paper analyses some otter (Lutra lutra spatial data, obtained by the location of genetically typed spraints in the Pollino national park and surrounding areas (southern Italy. A sample of 214 otter spraints was collected (27 faeces in 2001-02 and 187 in 2004 along 10 streams of the park, and their location was digitalized by a Geographic Information System (Arcview 3.1 for spatial analysis. DNA was extracted using the GuSCN/silica method and each faecal sample was genotyped by PCR amplification of twelve microsatellite loci. Finally, 103 (48.1% spraints yielded a reliable genotype, providing the identification of 31 otters. The maximum distance, measured along watercourses between the genotyped faecal samples of each individual identified by at least two faeces, varied from 0.02 to 34.8 km. On the whole, our results outlined a ranging pattern based on the occupation by one otter of a long stretch of watercourse (21.6 and 34.8 km, including 4-6 partially overlapped short stretches (from 0.02 to 14.1 km occupied by as many animals. RIASSUNTO – Spostamenti della Lontra Lutra lutra valutati mediante analisi genetica delle feci in Italia meridionale. Tramite l’estrazione del DNA da feci “fresche” e la succes- siva amplificazione di 12 loci microsatellite, da un campione di 214 feci di Lontra raccolto lungo 10 corsi idrici del Parco Nazionale del Pollino e aree limitrofe (27 feci nel 2001-02 e 187 nel 2004 sono stati ottenuti 103 genotipi affidabili (48,1%, consentendo l’identifi- cazione di 31 individui. La localizzazione delle feci genotipizzate è stata stabilita mediante GPS (Global Positioning System e trasferita su una mappa digitalizzata (scala 1:10000 tramite GIS (Geographic Information System. La distanza massima, misurata lungo i corsi idrici investigati, tra i campioni fecali tipizzati di ciascun individuo è variata da 0,02 a 34,8 km. Nel complesso, i risultati ottenuti hanno

  8. Mercury Hazard Assessment for Piscivorous Wildlife in Glacier National Park

    KAUST Repository

    Stafford, Craig P.

    2016-12-14

    We examined the mercury hazard posed to selected piscivorous wildlife in Glacier National Park (GNP), Montana. Logging Lake was our focal site where we estimated the dietary mercury concentrations of wildlife (common loon [Gavia immer], American mink [Neovison vison], river otter [Lontra canadensis], and belted kingfisher [Megaceryle alcyon]) by assuming that fishes were consumed in proportion to their relative abundances. To evaluate if Logging Lake provided a suitable baseline for our study, we made geographic comparisons of fish mercury levels and investigated the distribution and abundance of high mercury fishes within GNP. We complimented our assessment by examining selenium:mercury molar ratios in fishes from Logging Lake and Saint Mary Lake. Our results suggest fish consumption does not imperil wildlife from Logging Lake based on published thresholds for adverse mercury effects, but some hazard may exist particularly if there is strong feeding selectivity for the most contaminated species, northern pikeminnow (Ptychocheilus oregonensis). The geographic comparisons of fish mercury levels, together with the distribution and abundance of high mercury fishes within GNP, suggest that Logging Lake provided a relatively protective baseline among our study lakes. Risk may be further reduced by the molar excess of selenium relative to mercury, particularly in the smaller fishes typically consumed by GNP wildlife. Our findings contrast with studies from northeastern US and southeastern Canada where greater mercury hazard to wildlife exists. An emergent finding from our research is that waterborne concentrations of methylmercury may provide limited insight into regional differences in fish mercury levels.

  9. Water infiltration capacity under different land uses and agricultural management practices

    Directory of Open Access Journals (Sweden)

    Lizandra Poeta Teixeira

    2009-08-01

    Full Text Available Knowledge of physical and hydraulic properties of soil is important for the appropriate use and management of soil, and for the understanding of dynamic movement process of water and solutes. This study aims to determine the soil infiltration capacity of the Concordia Experimental Basin, located in the municipality of Lontras in Santa Catarina state. The infiltration tests were performed with the concentric ring infiltrometer, with a diameter of 25 and 50 cm on twenty sampling points showing different uses of land and agricultural management practices. The initial capacity of infiltration, calculated by Horton's equation, ranged from 0.8 (pasture to 5.0 cm min-1 (pine forest and cassava planting. In pasture areas, the initial infiltration ranged from 0.8 to 0.9 cm min-1. Regarding the minimum value, they ranged from 0.01 (perennial pasture to 0.3 cm min-1 (minimum tillage for corn. In forest areas, the minimum infiltration varied between 0.05 and 0.15 cm min-1 and in the areas of pasture, it was equal to 0.01 cm min-1.

  10. ECOLOGICAL EFFECTS OF METALS IN STREAMS ON A DEFENSE MATERIALS PROCESSING SITE IN SOUTH CAROLINA, USA

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.; Dyer, S.

    2009-09-01

    The Savannah River Site (SRS) is a 780 km{sup 2} U.S. Department of Energy facility near Aiken SC established in 1950 to produce nuclear materials. SRS streams are 'integrators' that potentially receive water transportable contaminants from all sources within their watersheds necessitating a GIS-based watershed approach to organize contaminant distribution data and accurately characterize the effects of multiple contaminant sources on aquatic organisms. Concentrations of metals in sediments, fish, and water were elevated in streams affected by SRS operations, but contaminant exposure models for Lontra Canadensis and Ceryle alcyon indicated that toxicological reference values were exceeded only by Hg and Al. Macroinvertebrate community structure was unrelated to sediment metal concentrations. This study indicated that (1) modeling studies and field bioassessments provide a complementary basis for addressing the individual and cumulative effects of contaminants, (2) habitat effects must be controlled when assessing contaminant impacts, (3) sensitivity analyses of contaminant exposure models are helpful in apportioning sampling effort, and (4) contaminants released during fifty years of industrial operations have not resulted in demonstrable harm to aquatic organisms in SRS streams.

  11. Behavioral responses of Pacific lamprey to alarm cues

    Science.gov (United States)

    Porter, Laurie L.; Hayes, Michael C.; Jackson, Aaron D.; Burke, Brian J.; Moser, Mary L.; Wagner, R. Steven

    2017-01-01

    Pacific lamprey (Entosphenus tridentatus), an anadromous ectoparasite, faces several challenges during adult migration to spawning grounds. Developing methods to address these challenges is critical to the success of ongoing conservation efforts. The challenges are diverse, and include anthropogenic alterations to the ecosystem resulting in loss of habitat, impassable barriers such as dams, climate change impacts, and altered predator fields. We conducted a behavioral study to understand how adult migrating Pacific lamprey respond to potential alarm cues: White Sturgeon (Acipenser transmontanus), human saliva, decayed Pacific lamprey, and river otter (Lontra canadensis). Research has shown that some species of lamprey can be guided to a location using odors and similar cues may be useful as a management tool for Pacific lamprey. Experiments were conducted over 2 nights and measured the number of entries (count) and duration of time spent (occupancy) by adult lamprey in each arm of a two-choice maze. During the first night, no odor was added to test for selection bias between arms. During the second night odor was added to one arm of the maze. Contrary to expectations, lamprey were significantly attracted to the river otter odor in both count and occupancy. No significant differences were found in the response of lamprey to the other three odors. Results from this study indicate that Pacific lamprey do respond to some odors; however, additional tests are necessary to better identify the types of odors and concentrations that elicit a repeatable response.

  12. Mercury Hazard Assessment for Piscivorous Wildlife in Glacier National Park

    KAUST Repository

    Stafford, Craig P.; Downs, Christopher C.; Langner, Heiko W.

    2016-01-01

    We examined the mercury hazard posed to selected piscivorous wildlife in Glacier National Park (GNP), Montana. Logging Lake was our focal site where we estimated the dietary mercury concentrations of wildlife (common loon [Gavia immer], American mink [Neovison vison], river otter [Lontra canadensis], and belted kingfisher [Megaceryle alcyon]) by assuming that fishes were consumed in proportion to their relative abundances. To evaluate if Logging Lake provided a suitable baseline for our study, we made geographic comparisons of fish mercury levels and investigated the distribution and abundance of high mercury fishes within GNP. We complimented our assessment by examining selenium:mercury molar ratios in fishes from Logging Lake and Saint Mary Lake. Our results suggest fish consumption does not imperil wildlife from Logging Lake based on published thresholds for adverse mercury effects, but some hazard may exist particularly if there is strong feeding selectivity for the most contaminated species, northern pikeminnow (Ptychocheilus oregonensis). The geographic comparisons of fish mercury levels, together with the distribution and abundance of high mercury fishes within GNP, suggest that Logging Lake provided a relatively protective baseline among our study lakes. Risk may be further reduced by the molar excess of selenium relative to mercury, particularly in the smaller fishes typically consumed by GNP wildlife. Our findings contrast with studies from northeastern US and southeastern Canada where greater mercury hazard to wildlife exists. An emergent finding from our research is that waterborne concentrations of methylmercury may provide limited insight into regional differences in fish mercury levels.

  13. Araguaia fold belt, new geochronological data

    International Nuclear Information System (INIS)

    Lafon, J.M.; Macambira, J.B.; Macambira, M.J.B.; Moura, C.A.V.; Souza, A.C.C.

    1990-01-01

    The northern part of the Araguaia Fold Belt (AFB) outcrops in a N-S direction for about 400 km in the state of Tocantins. Dome-like structures occur in this fold belt also in a N-S direction. Both deformation and metamorphism increase from the West to the East. The basement of the AFB consist of Colmeia complex and Cantao gneiss, which crop out mainly in the core of the dome-like structures. The supracrustals rocks of the fold belt belongs to the Baixo Araguaia supergroup which is divided into the lower Estrondo group and the upper Tocantins group. Preliminary Sm-Nd data from the Colmeia complex (Grota Rica dome) gave Archean model ages of 2.8 Ga (TNd sub(DM)) while Rb-Sr data in the same rocks give an age of 2530 ± 200 Ma. In the others dome-like structures, the Rb-Sr systematics gave ages for the Colmeia a complex of 2239 ± 47 Ma (Colmeia structure) and 1972 ± 46 Ma (Lontra structure). These younger ages are believed to represent partial to total isotopic resetting of the Rb-Sr system during the Transamazonian Event. The Rb-Sr studies of the Cantao gneiss gave an age of 1774 ± 31 Ma. (author)

  14. High-altitude diving in river otters: coping with combined hypoxic stresses.

    Science.gov (United States)

    Crait, Jamie R; Prange, Henry D; Marshall, Noah A; Harlow, Henry J; Cotton, Clark J; Ben-David, Merav

    2012-01-15

    River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O(2)) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 g dl(-1)) than sea-level otters (15.6 g dl(-1)). Yellowstone otters displayed higher levels of the vasodilator nitric oxide (NO), and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Despite compensation in several hematological and serological parameters, theoretical aerobic dive limits (ADL) were similar between high-elevation and sea-level otters because of the lower availability of O(2) at altitude. Our results suggest that recent disruptions to the Yellowstone Lake food web could be detrimental to otters because at this high elevation, constraints on diving may limit their ability to switch to prey in a deep-water environment.

  15. Plantas de ocorrência espontânea como substratos alternativos para fitoseídeos (Acari, Phytoseiidae em cultivos de seringueira Hevea brasiliensis Muell. Arg. (Euphorbiaceae Weeds as alternative substrates to phytoseiids (Acari, Phytoseiidae in rubber tree Hevea brasilienis, Muell. Arg. (Euphorbiaceae cultivation

    Directory of Open Access Journals (Sweden)

    Marcos Roberto Bellini

    2005-03-01

    Full Text Available O objetivo deste estudo foi determinar as espécies de plantas espontâneas em áreas de cultivo de seringueira que poderiam servir com reservatório de ácaros predadores. O trabalho foi conduzido em Olímpia, Estado de São Paulo, Brasil, em dois cultivos de seringueira. A cada três meses, cerca de 1.000 cm³ de folhas de cada uma das cinco espécies de plantas espontâneas dominantes em cada cultivo foi tomada para determinar os fitoseídeos. Como as plantas espontâneas dominantes variaram durante o estudo, um total de 20 espécies foi verificado. Somente Cecropia sp. foi dominante em todo estudo, em ambos os cultivos. Um total de 336 fitoseídeos pertencentes às seguintes espécies foi encontrado: Euseius citrifolius Denmark & Muma, 1970, E. concordis (Chant, 1959, Galendromus annectens (DeLeon, 1958, Iphiseiodes zuluagai Denmark & Muma, 1972, Neoseiulus anonymus (Chant & Baker, 1965 e N. tunus (DeLeon, 1967. E. citrifolius (189 espécimes e N. tunus (138 espécimes foram os mais abundantes. A maior abundância (231espécimes e diversidade (5 espécies foram observadas sobre Cecropia sp. Sobre esta planta foi encontrado o maior número de ácaros por amostra (29 espécimes, seguida por Piper duncum Linnaeus (22, Guarea sp. (18 e Ageratum conyzoides Linnaeus (12. E. citrifolius tem sido determinado como um dos ácaros predadores mais abundantes sobre seringueiras cultivadas na região onde este trabalho foi conduzido. Cecropia sp. parece ser uma das plantas espontâneas mais importantes consideradas como reservatório de E. citrifolius porque está continuamente presente nos cultivos. Estudos complementares poderiam indicar a viabilidade de se manejar esta planta nas áreas de cultivo de seringueira para permitir o controle biológico dos ácaros-praga desta cultura.The objective of this study was to determine weed species of rubber tree cultivation areas that could serve as reservoirs of predatory mites. The work was conducted in Ol

  16. A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian of northern Alaska

    Directory of Open Access Journals (Sweden)

    Hirotsugu Mori

    2016-02-01

    Full Text Available The Liscomb bonebed in the Price Creek Formation of northern Alaska has produced thousands of individual bones of a saurolophine hadrosaurid similar to Edmontosaurus; however, the specific identity of this taxon has been unclear, in part because the vast majority of the remains represent immature individuals. In this study, we address the taxonomic status of the Alaskan material through a comparative and quantitative morphological analysis of juvenile as well several near adult-sized specimens with particular reference to the two known species of Edmontosaurus, as well as a cladistic analysis using two different matrices for Hadrosauroidea. In the comparative morphological analysis, we introduce a quantitative method using bivariate plots to address ontogenetic variation. Our comparative anatomical analysis reveals that the Alaskan saurolophine possesses a unique suite of characters that distinguishes it from Edmontosaurus, including a premaxillary circumnarial ridge that projects posterolaterally without a premaxillary vestibular promontory, a shallow groove lateral to the posterodorsal premaxillary foramen, a relatively narrow jugal process of the postorbital lacking a postorbital pocket, a relatively tall maxilla, a relatively gracile jugal, a more strongly angled posterior margin of the anterior process of the jugal, wide lateral exposure of the quadratojugal, and a short symphyseal process of the dentary. The cladistic analyses consistently recover the Alaskan saurolophine as the sister taxon to Edmontosaurus annectens + Edmontosaurus regalis. This phylogenetic assessment is robust even when accounting for ontogenetically variable characters. Based on these results, we erect a new taxon, Ugrunaaluk kuukpikensis gen. et sp. nov. that contributes to growing evidence for a distinct, early Maastrichtian Arctic dinosaur community that existed at the northernmost extent of Laramidia during the Late Cretaceous.

  17. Sprainting activity of captive otters: its relationship with breeding cycle and number of animals

    Directory of Open Access Journals (Sweden)

    Claudio Prigioni

    1995-12-01

    Full Text Available Abstract The marking activity of captive otters (Lutra lutra was studied from April 1989 to August 1993 in an enclosure of 1.64 ha in size, located in the Ticino Valley Natural Park (Piemonte region, northern Italy. The number of otters in the enclosure varied from 1 to 6 and three litters of 1, 2 and 2 cubs were recorded in October 1990, 1991 and 1992. The sprainting activity, expressed as number of signs (spraints and anal secretions per day was associated to the breeding cycle and increased in relation to the number of animals present in the enclosure. These data are of particular importance in order to explain the annual variation of the marking level in wild otter populations. Riassunto Attività di marcamento di 1ontre in cattività in relazione a1 ciclo riproduttivo e a1 numero degli animali - L'attività di marcamento della lontra (Lutra lutra è stata rilevata dall'aprile 1989 all'agosto 1993 in un recinto di 1,64 ha, situato nel Parco Naturale della Valle del Ticino (regione Piemonte, provincia di Novara. I1 numero di animali presenti in tale recinto variava da 1 a 6, e la nascita di tre cucciolate, composte da 1, 2 e 2 piccoli, è stata registrata in ottobre negli anni 1990, 1991 e 1992. L'intensità di marcamento, espressa come numero di segni (feci e secrezioni anali per giorno era associata a1 ciclo riproduttivo della specie e incrementava in relazione al numero di animali presenti nel recinto. I dati acquisiti rivestono particolare importanza per interpretare le variazioni nell'arco dell'anno del livello di marcamento di popolazioni selvatiche.

  18. Estimating Mass Properties of Dinosaurs Using Laser Imaging and 3D Computer Modelling

    Science.gov (United States)

    Bates, Karl T.; Manning, Phillip L.; Hodgetts, David; Sellers, William I.

    2009-01-01

    Body mass reconstructions of extinct vertebrates are most robust when complete to near-complete skeletons allow the reconstruction of either physical or digital models. Digital models are most efficient in terms of time and cost, and provide the facility to infinitely modify model properties non-destructively, such that sensitivity analyses can be conducted to quantify the effect of the many unknown parameters involved in reconstructions of extinct animals. In this study we use laser scanning (LiDAR) and computer modelling methods to create a range of 3D mass models of five specimens of non-avian dinosaur; two near-complete specimens of Tyrannosaurus rex, the most complete specimens of Acrocanthosaurus atokensis and Strutiomimum sedens, and a near-complete skeleton of a sub-adult Edmontosaurus annectens. LiDAR scanning allows a full mounted skeleton to be imaged resulting in a detailed 3D model in which each bone retains its spatial position and articulation. This provides a high resolution skeletal framework around which the body cavity and internal organs such as lungs and air sacs can be reconstructed. This has allowed calculation of body segment masses, centres of mass and moments or inertia for each animal. However, any soft tissue reconstruction of an extinct taxon inevitably represents a best estimate model with an unknown level of accuracy. We have therefore conducted an extensive sensitivity analysis in which the volumes of body segments and respiratory organs were varied in an attempt to constrain the likely maximum plausible range of mass parameters for each animal. Our results provide wide ranges in actual mass and inertial values, emphasizing the high level of uncertainty inevitable in such reconstructions. However, our sensitivity analysis consistently places the centre of mass well below and in front of hip joint in each animal, regardless of the chosen combination of body and respiratory structure volumes. These results emphasize that future

  19. Estimating mass properties of dinosaurs using laser imaging and 3D computer modelling.

    Directory of Open Access Journals (Sweden)

    Karl T Bates

    Full Text Available Body mass reconstructions of extinct vertebrates are most robust when complete to near-complete skeletons allow the reconstruction of either physical or digital models. Digital models are most efficient in terms of time and cost, and provide the facility to infinitely modify model properties non-destructively, such that sensitivity analyses can be conducted to quantify the effect of the many unknown parameters involved in reconstructions of extinct animals. In this study we use laser scanning (LiDAR and computer modelling methods to create a range of 3D mass models of five specimens of non-avian dinosaur; two near-complete specimens of Tyrannosaurus rex, the most complete specimens of Acrocanthosaurus atokensis and Strutiomimum sedens, and a near-complete skeleton of a sub-adult Edmontosaurus annectens. LiDAR scanning allows a full mounted skeleton to be imaged resulting in a detailed 3D model in which each bone retains its spatial position and articulation. This provides a high resolution skeletal framework around which the body cavity and internal organs such as lungs and air sacs can be reconstructed. This has allowed calculation of body segment masses, centres of mass and moments or inertia for each animal. However, any soft tissue reconstruction of an extinct taxon inevitably represents a best estimate model with an unknown level of accuracy. We have therefore conducted an extensive sensitivity analysis in which the volumes of body segments and respiratory organs were varied in an attempt to constrain the likely maximum plausible range of mass parameters for each animal. Our results provide wide ranges in actual mass and inertial values, emphasizing the high level of uncertainty inevitable in such reconstructions. However, our sensitivity analysis consistently places the centre of mass well below and in front of hip joint in each animal, regardless of the chosen combination of body and respiratory structure volumes. These results emphasize