| use of a tiletamine-zolazepam mixture to immobilise wild grey seals and southern elephant seals. | a mixture of tiletamine and zolazepam at a combined dose of 1 mg/kg was a reliable and safe agent for immobilising wild grey seals (halichoerus grypus) and southern elephant seals (mirouga leonina). the agent had a number of advantages over all the other agents used previously. | 1990 | 2309387 |
| the use of a ketamine-diazepam mixture to immobilise wild grey seals (halichoerus grypus) and southern elephant seals (mirounga leonina). | a mixture of ketamine and diazepam, at doses of 6 mg/kg and 0.30 mg/kg respectively, proved to be a reliable and reasonably safe immobilisation agent for field work on grey and southern elephant seals. it was better than previously reported drugs used either singly or in combination. | 1988 | 3195003 |
| plasma concentrations of 25-hydroxyvitamin-d3 (calcifediol) as an indicator of ultraviolet radiation. | vitamin d3 is produced in the skin of animals and humans by the sun's ultraviolet rays (uvb region, 290-315 nm). the main metabolite 25-hydroxyvitamin-d3 has a seasonal variation, depending on the ultraviolet radiation. in the antarctic preliminary investigations on penguins (pygoscelis papua), female sea elephants (mirounga leonina), and humans showed that there was an increase in plasma 25-hydroxyvitamin-d3 concentrations during uv-exposure in all three species. this metabolite can therefore b ... | 1993 | 8305094 |
| molecular population genetics of the southern elephant seal mirounga leonina. | southern elephant seals breed on sub-antarctic islands and have a circumpolar distribution. we assayed mitochondrial dna (mtdna) and nuclear dna (ndna) variation in the three main populations in the south atlantic, south indian, and south pacific oceans, and a smaller continental population in south america. population structure of mtdna was strong and not consistent with isolation by distance. the ndna loci, although less informative, were consistent with the mtdna results. geographic structure ... | 1998 | 9691049 |
| molecular genetic diversity and evolution at the mhc dqb locus in four species of pinnipeds. | variation was investigated at exon 2 (including part of the putative peptide-binding region) of the class ii major histocompatibility complex (mhc) dqb locus for two congeneric phocid seal species and two congeneric otariid seal species. polymorphism in one phocid species, the southern elephant seal (mirounga leonina), was comparable to that seen in human populations, while the other phocid, the northern elephant seal (mirounga angustirostris), has been through a severe population bottleneck and ... | 1999 | 10335654 |
| pharmacokinetics of intravenously administered ketamine in southern elephant seals (mirounga leonina). | southern elephant seals (mirounga leonina) are large, potentially dangerous animals which must be restrained before study or treatment. however, chemical restraint is unpredictable, possibly because of differences in body composition during fasting ashore, and circulatory adaptations to enable diving. the pharmacokinetics of ketamine (1.1 mg/kg i.v.) was studied in 15 southern elephant seals which had come ashore on macquarie island. the animals were first sedated with pethidine (5 mg/kg i.m.) t ... | 1999 | 10530900 |
| arbovirus of marine mammals: a new alphavirus isolated from the elephant seal louse, lepidophthirus macrorhini. | a novel alphavirus was isolated from the louse lepidophthirus macrorhini, collected from southern elephant seals, mirounga leonina, on macquarie island, australia. the virus displayed classic alphavirus ultrastructure and appeared to be serologically different from known australasian alphaviruses. nearly all macquarie island elephant seals tested had neutralizing antibodies against the virus, but no virus-associated pathology has been identified. antarctic division personnel who have worked exte ... | 2001 | 11287559 |
| evolutionary relationships and systematics of the alphaviruses. | partial e1 envelope glycoprotein gene sequences and complete structural polyprotein sequences were used to compare divergence and construct phylogenetic trees for the genus alphavirus. tree topologies indicated that the mosquito-borne alphaviruses could have arisen in either the old or the new world, with at least two transoceanic introductions to account for their current distribution. the time frame for alphavirus diversification could not be estimated because maximum-likelihood analyses indic ... | 2001 | 11581380 |
| evidence of helicobacter sp. in dental plaque of captive dolphins (tursiops gephyreus). | gastrointestinal lesions have been extensively reported in wild and captive marine mammals. however, their etiology remains unclear. in humans and other animals, chronic gastritis and peptic ulcers have been associated with helicobacter sp. therefore, the aim of our study was to investigate the presence of helicobacter sp. in the gastric juice, dental plaque, and saliva of marine mammals living in a controlled environment. five dolphins (tursiops gephyreus), one killer whale (orcinus orca), one ... | 2002 | 12238390 |
| southern ocean frontal structure and sea-ice formation rates revealed by elephant seals. | polar regions are particularly sensitive to climate change, with the potential for significant feedbacks between ocean circulation, sea ice, and the ocean carbon cycle. however, the difficulty in obtaining in situ data means that our ability to detect and interpret change is very limited, especially in the southern ocean, where the ocean beneath the sea ice remains almost entirely unobserved and the rate of sea-ice formation is poorly known. here, we show that southern elephant seals (mirounga l ... | 2008 | 18695241 |
| ddt in endangered galapagos sea lions (zalophus wollebaeki). | we characterize for the first time the presence of ddt and its metabolites in tropical galapagos sea lions (zalophus wolleabeki). ?ddt concentrations in galapagos sea lion pups sampled in 2005 and 2008 ranged from 16 to 3070 µg/kg lipid. concentrations of ?ddt in pups in 2008 averaged 525 µg/kg lipid and were 1.9 times higher than that (281 µg/kg lipid) detected in pups in 2005. these concentrations are lower than those reported in many pinnipeds elsewhere, comparable to those in hawaiian monk s ... | 2011 | 21353257 |
| Indications for both host-specific and introduced genotypes of Staphylococcus aureus in marine mammals. | Staphylococcus aureus is present in the marine environment and causes disease in marine mammals. To determine whether marine mammals are colonized by host-specific strains or by strains originating from other species, we performed multi-locus sequence typing on ten S. aureus strains isolated from marine mammals in the U.K., the Netherlands, and the Antarctic. Four new sequence types of S. aureus were discovered. S. aureus strains from a southern elephant seal (n=1) and harbour porpoises (n=2) di ... | 2011 | 22112853 |
| n-terminal amino acid sequence of trypsinogen from the elephant seal mirounga leonina l. (carnivora). | | 2015 | 4834682 |
| prolonged and multiple immobilizations of the southern elephant seal using ketamine hydrochloride-xylazine hydrochloride or ketamine hydrochloride-diazepam combinations. | thirty seven southern elephant seals (mirounga leonina) were singularly or repeatedly immobilized with combinations of ketamine hydrochloride (hcl) and xylazine hcl or ketamine hcl and diazepam. atropine sulphate was included in the drug combinations. to permit experimental procedures the seals were immobilized for periods of 30-330 min. the mean induction dose of ketamine hcl was 8.71 +/- 0.25 mg/kg (mean +/- se). the mean induction time was 16.02 +/- 2.62 min. for the elephant seals immobilize ... | 2013 | 3682087 |
| detection of toxoplasma gondii antibodies in antarctic pinnipeds. | the presence of toxoplasma gondii antibodies was investigated in antarctic marine mammals. two hundred and eleven sera from different species of pinnipeds collected in years 2007, 2010 and 2011 from different locations in the south shetland islands and antarctic peninsula were analysed using a commercially available agglutination test kit. the presence of antibodies (titres ≥ 1:25) against t. gondii was detected in a total of 28 animals (13.3%). amongst animal species, percentages of detection w ... | 2012 | 22726387 |
| molecular systematics of pinniped hookworms (nematoda: uncinaria): species delimitation, host associations and host-induced morphometric variation. | hookworms of the genus uncinaria have been widely reported from juvenile pinnipeds, however investigations of their systematics has been limited, with only two species described, uncinaria lucasi from northern fur seals (callorhinus ursinus) and uncinaria hamiltoni from south american sea lions (otaria flavescens). hookworms were sampled from these hosts and seven additional species including steller sea lions (eumetopias jubatus), california sea lions (zalophus californianus), south american fu ... | 2013 | 24162075 |
| morphometric and molecular characterization of the species of uncinaria frölich, 1789 (nematoda) parasitic in the australian fur seal arctocephalus pusillus doriferus (schreber), with notes on hookworms in three other pinniped hosts. | this study presents morphological and molecular data on hookworms from the australian fur seal arctocephalus pusillus doriferus (schreber) currently identified in australian waters as uncinaria hamiltoni baylis, 1933. additional specimens from the australian sea lion neophoca cinerea (péron) and the new zealand fur seal arctocephalus forsteri (lesson) from australia, and the southern elephant seal mirounga leonina (linnaeus) from antarctica, were included. using the internal transcribed spacer ( ... | 2013 | 23595493 |
| foraging fidelity as a recipe for a long life: foraging strategy and longevity in male southern elephant seals. | identifying individual factors affecting life-span has long been of interest for biologists and demographers: how do some individuals manage to dodge the forces of mortality when the vast majority does not? answering this question is not straightforward, partly because of the arduous task of accurately estimating longevity in wild animals, and of the statistical difficulties in correlating time-varying ecological covariables with a single number (time-to-event). here we investigated the relation ... | 2012 | 22505993 |
| rapid response of a marine mammal species to holocene climate and habitat change. | environmental change drives demographic and evolutionary processes that determine diversity within and among species. tracking these processes during periods of change reveals mechanisms for the establishment of populations and provides predictive data on response to potential future impacts, including those caused by anthropogenic climate change. here we show how a highly mobile marine species responded to the gain and loss of new breeding habitat. southern elephant seal, mirounga leonina, rema ... | 2009 | 19593366 |
| persistent organic pollutants and stable isotopes in pinnipeds from king george island, antarctica. | in the present work, fat, skin, liver and muscle samples from leptonychotes weddellii (weddell seal, n=2 individuals), lobodon carcinophagus (crabeater seal, n=2), arctocephalus gazella (antarctic fur seal, n=3) and mirounga leonina (southern elephant seal, n=1) were collected from king george island, antarctica, and analysed for pops (pcbs, organochlorine pesticides and pbdes) and stable isotopes (δ¹³c and δ¹⁵n in all tissues but fat). pbdes could be found in only one sample (l. weddellii fat). ... | 2012 | 23154138 |
| lactational transfer of pcbs and chlorinated pesticides in pups of southern elephant seals (mirounga leonina) from antarctica. | seven pairs of southern elephant seals (mirounga leonina) pups and their dams were sampled during the late weaning season among a breeding population of seals on elephant island in antarctica. the blubber of the pups and the milk and blubber of their dams were analyzed for lipid-normalized concentrations of pcbs and organochlorines compounds in order to evaluate the lactational transfer of these contaminants. the lipid-normalized concentrations in these tissues were in the ppb range (i.e., ngg(- ... | 2009 | 19201445 |
| a phylogenomic study of the genus alphavirus employing whole genome comparison. | the phylogenetics of the genus alphavirus have historically been characterized using partial gene, single gene or partial proteomic data. we have mined cdna and amino acid sequences from genbank for all fully sequenced and some partially sequenced alphaviruses and generated phylogenomic analyses of the genus alphavirus genus, employing capsid encoding structural regions, non-structural coding regions and complete viral genomes. our studies support the presence of the previously reported recombin ... | 2005 | 18629194 |
| the better to eat you with: the comparative feeding morphology of phocid seals (pinnipedia, phocidae). | one adaptation crucial to the survival of mammalian lineages that secondarily transitioned from land to water environments was the ability to capture and consume prey underwater. phocid seals have evolved diverse feeding strategies to feed in the marine environment, and the objectives of this study were to document the specialized feeding morphologies and identify feeding strategies used by extant phocids. this study used principal component analysis (pca) to determine the major axes of diversif ... | 2016 | 26646351 |
| residues of persistent organochlorine contaminants in southern elephant seals (mirounga leonina) from elephant island, antarctica. | contamination of blubber tissues by organochlorine pesticides (oc) and pcbs was assessed in female and male pups and juveniles, as well as in adult females and subdominant adult males of the southern elephant seal, mirounga leonina, from elephant island in the antarctic peninsula. all residues of persistent organochlorine contaminants analyzed were found in blubber samples, except for beta-hch, endosulfan ii, endrin, heptachlor, and aldrin. the relative concentrations of the analytes detected we ... | 2007 | 17612156 |
| successful foraging zones of southern elephant seals from the kerguelen islands in relation to oceanographic conditions. | southern elephant seals, mirounga leonina, undertake large-scale oceanic movements to access favourable foraging areas. successful foraging areas of elephant seals from the kerguelen islands are investigated here in relation to oceanographic parameters. movements and diving activity of the seals as well as oceanographic data were collected through a new generation of satellite relayed devices measuring and transmitting locations, pressure, temperature and salinity. for the first time, we have as ... | 2007 | 17472917 |
| holocene elephant seal distribution implies warmer-than-present climate in the ross sea. | we show that southern elephant seal (mirounga leonina) colonies existed proximate to the ross ice shelf during the holocene, well south of their core sub-antarctic breeding and molting grounds. we propose that this was due to warming (including a previously unrecognized period from approximately 1,100 to 2,300 (14)c yr b.p.) that decreased coastal sea ice and allowed penetration of warmer-than-present climate conditions into the ross embayment. if, as proposed in the literature, the ice shelf su ... | 2006 | 16801535 |
| speciation, population structure, and demographic history of the mojave fringe-toed lizard (uma scoparia), a species of conservation concern. | the north american deserts were impacted by both neogene plate tectonics and quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. we tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the mojave fringe-toed lizard (uma scoparia), a sand dune specialist endemic to the mojave desert of california and arizona. we sampled 109 individual lizards representing 22 insular dun ... | 2014 | 25360285 |
| how to build a deep diver: the extreme morphology of mesoplodonts. | mesoplodont beaked whales are extreme divers, diving for over 45 mins and to depths of over 800 m. these dives are of similar depth and duration to those of the giant sperm whale (physeter macrocephalus) whose body mass can be 50 times larger. velten et al. (2013) provided anatomical data that demonstrated that on-board oxygen stores were sufficient to aerobically support the extreme dives of mesoplodonts if their diving metabolic rates are low. because no physiological data yet exist, we utiliz ... | 2016 | 27940620 |
| growth in pinnipeds. | this review presents summary figures of, and fits growth curves to, data on body lengths (as standard length, sl, whenever possible) of pinnipeds at ages estimated to o.i y. (1) generalized von bertalanffy (vb) growth curves are fitted to most data: lx = l infinity (i - ea(x-x0)b, lx is length at age x, x0 is the origin of the curve (here chosen a priori as time of initiation of embryonic growth), l infinity is asymptotic length, a (which is negative) determines rate of approach to the asymptote ... | 1993 | 8457634 |
| handling intensity and the short- and long-term survival of elephant seals: addressing and quantifying research effects on wild animals. | this study addresses the consequences of repeated human handling on the survival of an endangered phocid, the southern elephant seal and the implications for wildlife research. southern elephant seal pups were repeatedly handled during the first six weeks of their lives. the possibility that such anthropogenic research may have altered the very parameters that were being investigated is a topical and relevant study area that we address here. our results show that there were no measurable effects ... | 2005 | 16201211 |
| climate change and seal survival: evidence for environmentally mediated changes in elephant seal, mirounga leonina, pup survival. | maternal and physical factors play a significant role in animal life-history variability, which means that large scale climate change has the potential to affect the size and dynamics of animal populations indirectly through maternal investment and directly through conditions that animals are exposed to. however, little is known about the effects of large-scale oceanographic events such as the el-niño southern oscillation (enso) that influence productivity in the southern ocean and the abundance ... | 2005 | 16024347 |
| corynosoma australe johnston, 1937 and c. cetaceum johnston & best, 1942 (acanthocephala: polymorphidae) from marine mammals and fishes in argentinian waters: allozyme markers and taxonomic status. | genetic and morphological studies were carried out on acanthocephalans belonging to corynosoma lühe, 1904 and referable to the species c. cetaceum johnston & best, 1942 and c. australe johnston, 1937, which were recovered from both definitive and intermediate hosts in argentinian waters. the aims were to estimate the level of genetic differentiation between the two taxa at any stage of their life-cycle, to provide genetic (allozyme) markers for their recognition and to analyse the systematic sta ... | 2005 | 15980967 |
| jeotgalicoccus pinnipedialis sp. nov., from a southern elephant seal (mirounga leonina). | a previously unknown gram-positive, catalase-positive, facultatively anaerobic, non-spore-forming, coccus-shaped bacterium (a/g14/99/10(t)), originating from the mouth of a female southern elephant seal, was subjected to a taxonomic analysis. comparative 16s rrna gene-sequencing showed that the organism formed a hitherto unknown subline within the catalase-positive, low-g+c, gram-positive cocci, exhibiting a specific association with species of the genus jeotgalicoccus. sequence divergence value ... | 2004 | 15143018 |
| increasing levels and biomagnification of persistent organic pollutants (pops) in antarctic biota. | representatives of the antarctic food web (krill, cephalopod, fish, penguin, seal) of the area around elephant island and from the weddell sea were analysed for the most recalcitrant organochlorine compounds. due to sorption of the compounds to sinking particles and accumulation in sediments, two benthic fish species (gobionotothen gibberifrons, chaenocephalus aceratus) feeding on benthos invertebrates and fish reflected significantly increasing concentrations within a decade (1987-1996), while ... | 2004 | 14972581 |
| metabolic biochemistry and the making of a mesopelagic mammal. | large seals such as northern and southern elephant seals and weddell seals are able to dive for startling duration and enormous depth. the current dive duration record is 120 minutes (recorded for the southern elephant seal); the current depth record is 1.5 km (recorded for the northern elephant seal). equally striking is the widespread observation that these seals when at sea spend close to 90% of the time submerged and often at great depth. for practical purposes, these species can be viewed a ... | 1992 | 1612137 |
| blubber and buoyancy: monitoring the body condition of free-ranging seals using simple dive characteristics. | elephant seals regularly perform dives during which they spend a large proportion of time drifting passively through the water column. the rate of vertical change in depth during these "drift" dives is largely a result of the proportion of lipid tissue in the body, with fatter seals having higher (more positive or less negative) drift rates compared with leaner seals. we examined the temporal changes in drift rates of 24 newly weaned southern elephant seal (mirounga leonina) pups during their fi ... | 2003 | 12939372 |
| estimating resource acquisition and at-sea body condition of a marine predator. | 1. body condition plays a fundamental role in many ecological and evolutionary processes at a variety of scales and across a broad range of animal taxa. an understanding of how body condition changes at fine spatial and temporal scales as a result of interaction with the environment provides necessary information about how animals acquire resources. 2. however, comparatively little is known about intra- and interindividual variation of condition in marine systems. where condition has been studie ... | 2013 | 23869551 |
| plasma melatonin concentration in neonatal northern elephant seals, mirounga angustirostris. | the development of pineal function in northern elephant seals was examined in an attempt to understand the physiological basis for previously observed high daytime levels of melatonin in neonatal southern elephant seals. pineal glands from four northern elephant seal pups, estimated age less than 1 week, weighted 3.0 +/- 0.80 g, which was significantly less than that previously found in southern elephant seals (4.6 +/- 0.35 g). midday concentrations of plasma melatonin in pups averaged more than ... | 1994 | 7828030 |
| multiple nuclear-gene phylogenies: application to pinnipeds and comparison with a mitochondrial dna gene phylogeny. | phylogenetic analyses of closely related species should use information from multiple, independent genes with relatively high rates of sequence evolution. to investigate species for which there are few prior sequence data for single-copy nuclear (scndna) genes, primers for gene amplification can be designed to highly conserved regions of exons in order to amplify both coding (exons) and noncoding (introns) sequences. we have explored this approach in a phylogenetic analysis of six species of pin ... | 1994 | 8015430 |
| elephant seal genetic variation and the use of simulation models to investigate historical population bottlenecks. | because the northern elephant seal (mirounga angustirostrus) was heavily exploited during the 19th century, it experienced an extreme population bottleneck. since then, under legislative protection in the united states and mexico, northern elephant seals have recovered dramatically in number, although their genomic diversity was greatly reduced, apparently as a consequence of the bottleneck. in this study we investigated dna sequence diversity in two mtdna regions (the control region and 16s rna ... | 2008 | 7505788 |
| bio-physical characterisation of polynyas as a key foraging habitat for juvenile male southern elephant seals (mirounga leonina) in prydz bay, east antarctica. | antarctic coastal polynyas are persistent open water areas in the sea ice zone, and regions of high biological productivity thought to be important foraging habitat for marine predators. this study quantified southern elephant seal (mirounga leonina) habitat use within and around the polynyas of the prydz bay region (63°e- 88°e) in east antarctica, and examined the bio-physical characteristics structuring polynyas as foraging habitat. output from a climatological regional ocean model was used to ... | 2017 | 28902905 |
| three-dimensional space use during the bottom phase of southern elephant seal dives. | in marine pelagic ecosystems, the spatial distribution of biomass is heterogeneous and dynamic. at large scales, physical processes are the main driving forces of biomass distribution. at fine scales, both biotic and abiotic parameters are likely to be key determinants in the horizontal and vertical distribution of biomass, with direct consequences on the foraging behaviour of diving predators. however, fine scale three-dimensional (3d) spatial interactions between diving predators and their pre ... | 2017 | 28861272 |
| you are what you eat: describing the foraging ecology of southern elephant seals (mirounga leonina) using blubber fatty acids. | understanding the trophodynamics of marine ecosystems requires data on the temporal and spatial variation in predator diet but, particularly for wide-ranging species, these data are often unavailable. the southern elephant seal (mirounga leonina) consumes large quantities of fish and squid prey in the southern ocean relative to other marine mammals; however, how diet varies relative to seasonal and spatial foraging behaviour is unknown. we used fatty acid (fa) signature analysis of 63 blubber co ... | 2003 | 12816642 |
| genetic evidence for two sibling species within contracaecum ogmorhini johnston & mawson, 1941 (nematoda: anisakidae) from otariid seals of boreal and austral regions. | genetic variation of contracaecum ogmorhini (sensu lato) populations from different otariid seals of the northern and southern hemisphere was studied on the basis of 18 enzyme loci as well as preliminary sequence analysis of the mitochondrial cyt b gene (260 bp). samples were collected from zalophus californianus in the boreal region and from arctocephalus pusillus pusillus, a. pusillus doriferus and a. australis from the austral region. marked genetic heterogeneity was found between c. ogmorhin ... | 2003 | 12567006 |
| blood chemistry in southern elephant seal mothers and pups during lactation reveals no effect of handling. | serum clinical chemistry parameters were examined in lactating southern elephant seal mirounga leonina mothers and their pups from the declining macquarie island population. there were significant changes in serum values from 2 to 21 days postpartum in both nursing mothers (increase: inorganic phosphate; decrease: creatinine, potassium, chloride, cholesterol, total protein, albumin, globulin, aspartate aminotransferase, creatine kinase) and suckling pups (increase: inorganic phosphate, globulin, ... | 2002 | 12208307 |
| facklamia miroungae sp. nov., from a juvenile southern elephant seal (mirounga leonina). | an unusual gram-positive, catalase-negative, facultatively anaerobic, coccus-shaped organism that originated from a juvenile elephant seal was characterized by phenotypic and molecular taxonomic methods. comparative 16s rrna gene sequencing showed that the unknown coccus represents a new subline within the genus facklamia. the unknown strain was readily distinguishable from all currently recognized species of the genus facklamia (facklamia hominis, facklamia languida, facklamia ignava, facklamia ... | 2001 | 11491339 |
| big data analyses reveal patterns and drivers of the movements of southern elephant seals. | the growing number of large databases of animal tracking provides an opportunity for analyses of movement patterns at the scales of populations and even species. we used analytical approaches, developed to cope with "big data", that require no 'a priori' assumptions about the behaviour of the target agents, to analyse a pooled tracking dataset of 272 elephant seals (mirounga leonina) in the southern ocean, that was comprised of >500,000 location estimates collected over more than a decade. our a ... | 2017 | 28273915 |
| postweaning duration and body composition changes in southern elephant seal (mirounga leonina) pups at king george island. | weaning mass in southern elephant seals is highly variable, the heaviest pups being three times as heavy as the lightest ones. after weaning, pups undergo an extensive postweaning period in which they draw on their reserves. to quantify the energy expenditure during the postweaning period, changes in mass, body composition, and postweaning duration were measured in southern elephant seals at king george island, south shetland islands, antarctica. overall, mean pup weaning mass was 154 +/- 26 kg ... | 2001 | 11436137 |
| lipid composition of blood platelets and erythrocytes of southern elephant seal (mirounga leonina) and antarctic fur seal (arctocephalus gazella). | erythrocyte and blood platelet phospholipid compositions were studied in three elephant seals and two fur seals, two species of marine mammals living in the subantarctic region feeding on preys rich in (n-3) polyunsaturated fatty acids. results were compared with those reported for related species and humans. in erythrocytes, the phospholipid (pl) and cholesterol (chol) contents were lower in pinnipeds than in humans. phosphatidylcholine (pc) levels were higher in elephant seals than in fur seal ... | 2000 | 10825663 |
| immunoglobulin m serum levels in females and pups of southern elephant seal (mirounga leonina) during the suckling period. | this paper reports immunoglobulin m (igm) levels in serum samples from eight female-pup pairs of southern elephant seals (mirounga leonina), at king george island, antarctica. igm levels were determined on sera obtained from sequential sampling throughout the suckling period (approximately 23 days). the igm concentration in southern elephant seal serum was measured by single radial immunodiffusion on agarose plates. female igm levels (123.5-613.0 mg/dl, n = 8) were significantly higher than pup ... | 1998 | 9683413 |
| concentrations, metabolic clearance rates, production rates and plasma binding of cortisol in antarctic phocid seals. | we have reported previously that plasma of the weddell seal, a member of the phocid family, contains a very high concentration of cortisol. the present study was undertaken to determine whether high cortisol levels were common to seals in the antarctic environment, or to other phocidae, and to determine the mechanism of the hypercortisolaemia. high levels of cortisol (0.82-2.38 mumol/l) were found in 4 phocidae (weddell, crabeater, leopard and southern elephant seals), whereas levels in a member ... | 1993 | 8237255 |
| southern elephant seals replenish their lipid reserves at different rates according to foraging habitat. | assessing energy gain and expenditure in free ranging marine predators is difficult. however, such measurements are critical if we are to understand how variation in foraging efficiency, and in turn individual body condition, is impacted by environmentally driven changes in prey abundance and/or accessibility. to investigate the influence of oceanographic habitat type on foraging efficiency, ten post-breeding female southern elephant seals mirounga leonina (ses) were equipped and tracked with bi ... | 2016 | 27902786 |
| thyroid morphology and function and its role in thermoregulation in the newborn southern elephant seal (mirounga leonina) at macquarie island. | the thyroid gland of the newborn southern elephant seal pup exhibits markedly increased secretory activity during the first 24 hours after birth. thyroid epithelial cell height is cuboidal to columnar for pups from birth to 48 hours postpartum after which it decreases by five days of age. ultrastructurally the thyroid epithelial cells show pseudopodia protruding into the lumen at zero, two and six hours after birth. after 24 hours postpartum pseudopodia are rarely observed in thyroid follicles f ... | 1991 | 1917675 |
| disease and injury in the southern elephant seal. | disease and injury was recorded in 170 tagged soughern elephant seals (mirounga leonina) on the antarctic continent. trauma due to interspecific predation was the most common disorder. no small seals were observed with lesions attributable to this in the antarctic population. this finding differs from data recorded in a sub-antarctic (macquarie island) population where seals of all class sizes exhibit lesions due to interspecific trauma. no external parasites were observed in the antarctic popul ... | 1977 | 856149 |
| summer and winter cycles in plasma melatonin levels in the elephant seal (mirounga leonina). | plasma melatonin concentration of immature male elephant seals was determined by radioimmunoassay. comparison of concentrations during two 24-h periods, one in midsummer and one in midwinter, showed that there was a marked circadian cycle in winter which was greatly modified during the long day length of summer. it is suggested that in summer there was sufficient ambient lighting during the night hours to depress the nocturnal rise in plasma melatonin. the complexity of pineal cycles in the natu ... | 1979 | 549553 |
| relating diving behavior and antioxidant status: insights from oxidative stress biomarkers in the blood of two distinct divers, mirounga leonina and arctocephalus australis. | pinnipeds rely upon diving to perform essential activities, including foraging. as pulmonated animals, oxygen privation experienced during submergence represents a considerable challenge both physiologically and biochemically. routine exposure to hypoxia and the rapid transitions between ischemia/reperfusion of tissues leads to extremely high reactive oxygen species (ros) production, which must be opposed by antioxidant defenses to avoid oxidative stress. the diving behaviors and capabilities of ... | 2014 | 24607367 |
| brucella antibody seroprevalence in antarctic seals (arctocephalus gazella, leptonychotes weddellii and mirounga leonina). | brucellosis is a worldwide infectious zoonotic disease caused by gram-negative bacteria of the genus brucella, and brucella infections in marine mammals were first reported in 1994. a serosurvey investigating the presence of anti-brucella antibodies in 3 antarctic pinniped species was undertaken with a protein a/g indirect enzyme-linked immunosorbent assay (ielisa) and the rose bengal test (rbt). serum samples from 33 weddell seals leptonychotes weddelli were analysed, and antibodies were detect ... | 2013 | 23999701 |
| relative abundance and behavior of marine mammals exposed to transmissions from the heard island feasibility test. | the heard island feasibility test source transmitted a hum at 209-220 db re: 1 micropa at 175-m depth, centered on 57 hz with a maximum bandwidth of 30 hz for 1 h of every 3. experienced marine mammal observers conducted line-transect surveys and monitored marine mammal behavior visually and acoustically in a 70 x 70 km square centered on the transmission site. thirty-nine groups of cetaceans and 19 of pinnipeds were sighted from both vessels before the start of transmissions. thirty-nine groups ... | 1994 | 7963037 |
| effects of physiological state on duration of sedation in southern elephant seals. | one hundred eighty-one female and thirteen postweanling pup southern elephant seals (mirounga leonina) were sedated using a combination of ketamine hydrochloride and xylazine hydrochloride. physiological state had a profound effect on response of the animals to sedation. physiologically stressed postlactation and postpartum cows had significantly longer periods of sedation than pre-molting females or recently weaned pups. induction time was not affected by physiological status. dose rates are re ... | 1989 | 2810559 |
| spatially explicit estimates of prey consumption reveal a new krill predator in the southern ocean. | development in foraging behaviour and dietary intake of many vertebrates are age-structured. differences in feeding ecology may correlate with ontogenetic shifts in dispersal patterns, and therefore affect foraging habitat and resource utilization. such life-history traits have important implications in interpreting tropho-dynamic linkages. stable isotope ratios in the whiskers of sub-yearling southern elephant seals (mirounga leonina; n = 12) were used, in conjunction with satellite telemetry a ... | 2014 | 24516515 |
| age-specific cost of first reproduction in female southern elephant seals. | when to commence breeding is a crucial life-history decision that may be the most important determinant of an individual's lifetime reproductive output and can have major consequences on population dynamics. the age at which individuals first reproduce is an important factor influencing the intensity of potential costs (e.g. reduced survival) involved in the first breeding event. however, quantifying age-related variation in the cost of first reproduction in wild animals remains challenging beca ... | 2014 | 24872464 |
| detection of a novel genotype of cryptosporidium in antarctic pinnipeds. | a study was conducted to investigate the presence of cryptosporidium and giardia in antarctic marine mammals. a total of 270 faecal samples from different species of pinnipeds from different locations in the south shetland islands and antarctic peninsula were analysed by immunofluorescence microscopy and pcr. cryptosporidium was detected by pcr in three samples from southern elephant seals (mirounga leonina) and 2 weddell seals (leptonychotes weddellii). however, no oocysts were observed in any ... | 2013 | 23021408 |
| detection and characterization of a cryptosporidium isolate from a southern elephant seal (mirounga leonina) from the antarctic peninsula. | the presence of cryptosporidium and giardia in 221 fecal samples from different species of antarctic pinnipeds was investigated by immunofluorescence microscopy and pcr. cryptosporidium, a skunk-like genotype, was detected only in a southern elephant seal. giardia was not detected. this is the first report of a cryptosporidium sp. in antarctic marine mammals. | 2011 | 21169427 |
| conservation of mhc class ii doa sequences among carnivores. | we obtained the nucleotide sequence for most of the major histocompatibility complex (mhc) class ii doa locus for weddell, leopard, northern elephant, and southern elephant seals and from the coyote and compared them to all known doa data available to date. we found generally low levels of interspecific polymorphisms, providing further support for stabilizing selection acting on the doa locus. this suggests that do gene products play a substantial functional role in the regulation of antigen pre ... | 2005 | 15730524 |
| the immunocompetence handicap hypothesis in two sexually dimorphic pinniped species--is there a sex difference in immunity during early development? | the 'immunocompetence handicap hypothesis' predicts that highly sexually dimorphic and polygynous species will exhibit sex differences in immunity. we tested this hypothesis in southern elephant and grey seals during their early development by measuring the following parameters: leucocyte counts, serum igg levels, erythrocyte sedimentation rate and haematocrit. we failed to find any differences due to sex as assessed by the parameters investigated. animals were sampled longitudinally during thei ... | 2006 | 12697319 |
| diet and phylogeny shape the gut microbiota of antarctic seals: a comparison of wild and captive animals. | the gut microbiota of mammals underpins the metabolic capacity and health of the host. our understanding of what influences the composition of this community has been limited primarily to evidence from captive and terrestrial mammals. therefore, the gut microbiota of southern elephant seals, mirounga leonina, and leopard seals, hydrurga leptonyx, inhabiting antarctica were compared with captive leopard seals. each seal exhibited a gut microbiota dominated by four phyla: firmicutes (41.5 ± 4.0%), ... | 2013 | 23145888 |
| immobilisation of southern elephant seals and leopard seals with cyclohexamine anaesthetics and xylazine. | ketamine and xylazine were given to 55 southern elephant seals (mirounga leonina) for stomach lavaging, and to three leopard seals (hydrurga leptonyx). the elephant seals showed prolonged apnoea and two of them died owing to aspiration of stomach contents. two of the leopard seals died from unknown causes. tiletamine and zolazepam were given to five elephant seals and one leopard seal. two of the elephant seals and the leopard seal died from unknown causes. xylazine alone was administered to 34 ... | 1991 | 1750175 |
| a new method to quantify within dive foraging behaviour in marine predators. | studies on diving behaviour classically divide a dive into three phases: the descent, bottom and ascent phases, with foraging assumed to occur during the bottom phase. the greater complexity of dive revealed through modern, high resolution data highlights the need to re-assess this approach and to consider a larger number of phases within individual dives. two southern elephant seals (ses) were fitted with a head mounted time depth recorder (tdr) and an accelerometer from which prey capture atte ... | 2014 | 24922323 |
| how large is large: estimating ecologically meaningful isotopic differences in observational studies of wild animals. | in ecological studies of wildlife movements and foraging, bio-logging and isotopic data are routinely collected and increasingly analyzed in tandem. such analyses have two shortcomings: (1) small sample size linked with the number of telemetric tags that can be deployed, and (2) the observational nature of isotopic gradients. wildlife ecologists are thus put in a statistical conundrum known as the small n, large p problem. | 2012 | 23124655 |
| relationship between chlorophyll a concentration, light attenuation and diving depth of the southern elephant seal mirounga leonina. | recently, a number of antarctic marine environmental studies have used oceanographic parameters collected from instrumented top predators for ecological and physical information. phytoplankton concentration is generally quantified through active measurement of chlorophyll fluorescence. in this study, light absorption coefficient (k(0.75)) was used as an indicator of phytoplankton concentration. this measurement, easy to obtain and requiring low electric power, allows for assessing of the fine sc ... | 2012 | 23082166 |
| arteriovenous anastomoses in the skin of seals. i. the weddell seal leptonychotes weddelli and the elephant seal mirounga leonina (pinnipedia: phocidae). | the structure, distribution, density and innervation of arteriovenous anastomoses (avas) have been compared in the skin of weddell and elephant seals, as part of a study of the structure and function of arteriovenous anastomoses in mammals. in both genera avas were coiled vessels with the segmental structure typical of "epithelioid" anastomoses and possessed a dense peripheral adrenergic innervation. in both weddell and elephant seals there was no statistically significant difference between the ... | 1978 | 666019 |
| decadal changes in habitat characteristics influence population trajectories of southern elephant seals. | understanding divergent biological responses to climate change is important for predicting ecosystem level consequences. we use species habitat models to predict the winter foraging habitats of female southern elephant seals and investigate how changes in environmental variables within these habitats may be related to observed decreases in the macquarie island population. there were three main groups of seals that specialized in different ocean realms (the sub-antarctic, the ross sea and the vic ... | 2017 | 28590592 |
| estimation and simulation of foraging trips in land-based marine predators. | the behavior of colony-based marine predators is the focus of much research globally. large telemetry and tracking data sets have been collected for this group of animals, and are accompanied by many empirical studies that seek to segment tracks in some useful way, as well as theoretical studies of optimal foraging strategies. however, relatively few studies have detailed statistical methods for inferring behaviors in central place foraging trips. in this paper we describe an approach based on h ... | 2017 | 28470722 |
| marine bioluminescence: measurement by a classical light sensor and related foraging behavior of a deep diving predator. | bioluminescence is produced by a broad range of organisms for defense, predation or communication purposes. southern elephant seal (ses) vision is adapted to low-intensity light with a peak sensitivity, matching the wavelength emitted by myctophid species, one of the main preys of female ses. a total of 11 satellite-tracked female sess were equipped with a time-depth-light 3d accelerometer (tdr10-x) to assess whether bioluminescence could be used by sess to locate their prey. firstly, we demonst ... | 2017 | 28425091 |
| five decades on: use of historical weaning size data reveals that a decrease in maternal foraging success underpins the long-term decline in population of southern elephant seals (mirounga leonina). | | 2017 | 28301546 |
| southern elephant seals (mirounga leonina linn.) depredate toothfish longlines in the midnight zone. | humans have devised fishing technologies that compete with marine predators for fish resources world-wide. one such fishery for the patagonian toothfish (dissostichus eleginoides) has developed interactions with a range of predators, some of which are marine mammals capable of diving to extreme depths for extended periods. a deep-sea camera system deployed within a toothfish fishery operating in the southern ocean acquired the first-ever video footage of an extreme-diver, the southern elephant s ... | 2017 | 28234988 |
| variability in sea ice cover and climate elicit sex specific responses in an antarctic predator. | contrasting regional changes in southern ocean sea ice have occurred over the last 30 years with distinct regional effects on ecosystem structure and function. quantifying how antarctic predators respond to such changes provides the context for predicting how climate variability/change will affect these assemblages into the future. over an 11-year time-series, we examine how inter-annual variability in sea ice concentration and advance affect the foraging behaviour of a top antarctic predator, t ... | 2017 | 28233791 |
| acoustic measurements of post-dive cardiac responses in southern elephant seals (mirounga leonina) during surfacing at sea. | measuring physiological data in free-ranging marine mammals remains challenging, owing to their far-ranging foraging habitat. yet, it is important to understand how these divers recover from effort expended underwater, as marine mammals can perform deep and recurrent dives. among them, southern elephant seals (mirounga leonina) are one of the most extreme divers, diving continuously at great depth and for long duration while travelling over large distances within the southern ocean. to determine ... | 2017 | 28202583 |
| how elephant seals (mirounga leonina) adjust their fine scale horizontal movement and diving behaviour in relation to prey encounter rate. | understanding the diving behaviour of diving predators in relation to concomitant prey distribution could have major practical applications in conservation biology by allowing the assessment of how changes in fine scale prey distribution impact foraging efficiency and ultimately population dynamics. the southern elephant seal (mirounga leonina, hereafter ses), the largest phocid, is a major predator of the southern ocean feeding on myctophids and cephalopods. because of its large size it can car ... | 2016 | 27973587 |
| seal mothers expend more on offspring under favourable conditions and less when resources are limited. | in mammals, maternal expenditure on offspring is a complex mix of several factors including the species' mating system, offspring sex and the condition and age of the mother. while theory suggests that in polygynous species mothers should wean larger male offspring than females when resources and maternal conditions allow, the evidence for this remains equivocal. southern elephant seals are highly dimorphic, polygynous capital breeders existing in an environment with highly variable resources an ... | 2017 | 27859273 |
| population differentiation in the context of holocene climate change for a migratory marine species, the southern elephant seal. | understanding observed patterns of connectivity requires an understanding of the evolutionary processes that determine genetic structure among populations, with the most common models being associated with isolation by distance, allopatry or vicariance. pinnipeds are annual breeders with the capacity for extensive range overlap during seasonal migrations, establishing the potential for the evolution of isolation by distance. here, we assess the pattern of differentiation among six breeding colon ... | 2016 | 27012933 |
| sex-specific foraging strategies and resource partitioning in the southern elephant seal (mirounga leonina). | the evolution of resource specializations is poorly understood, especially in marine systems. the southern elephant seal (mirounga leonina) is the largest of the phocid seals, sexually dimorphic, and thought to prey predominantly on fish and squid. we collected vibrissae from male and female southern elephant seals, and assessed stable c and n isotope ratios along the length of the vibrissae. given that whiskers grow slowly, this sampling strategy reflects any variation in feeding behaviour over ... | 2006 | 17015314 |
| serum immunoglobulin g concentration in southern elephant seal, mirounga leonina (linnaeus, 1758), from elephant island (antarctica): sexual and adrenal steroid hormones effects. | serum immunoglobulin g (igg; indirect enzyme-linked immunosorbent assay), as well as sexual and adrenal steroid hormones' concentrations (radioimmunoassay) were determined in 63 (male and female) southern elephant seals (mirounga leonine) at different developmental stages (weaned pups, juveniles and adults). in females, igg values (mean+/-s.d.) were higher (p<0.05) in adults (15.9+/-6.5mg ml(-1)) than in juveniles (7.9+/-4.0mg ml(-1)), but similar to weaned pups (12.0+/-5.0mg ml(-1)). estrogen c ... | 2005 | 15963822 |
| juvenile southern elephant seals exhibit seasonal differences in energetic requirements and use of lipids and protein stores. | growing juvenile animals undergo many morphological, physiological, and behavioural changes that influence their energetic requirements, patterns of energy use, and ultimately, their survival and reproductive success. we examined changes in mass loss and body composition of juvenile southern elephant seals (1- and 2-yr-olds) during their two annual haul-outs. at the start and end of the midyear and molt haul-outs, we caught, weighed, and measured 41 and 14 seals, respectively. we measured blubbe ... | 2016 | 15957104 |
| serum leptin concentration during the terrestrial phase of the southern elephant seal mirounga leonina (carnivora: phocidae). | this study aimed to verify the serum leptin concentration during the terrestrial phase of the southern elephant seal (mirounga leonina) on elephant island (south shetlands, antarctica). sera from 25 adult southern elephant seals were analyzed. leptin concentration was determined using the 125i radioimmunoassay method. total protein, triglycerides, and cholesterol concentration were measured by spectrophotometric methods. seals were grouped by sex and their physiological status (reproducing or mo ... | 2004 | 15504391 |
| dissolved oxygen sensor in animal-borne instruments: an innovation for monitoring the health of oceans and investigating the functioning of marine ecosystems. | the current decline in dissolved oxygen concentration within the oceans is a sensitive indicator of the effect of climate change on marine environment. however the impact of its declining on marine life and ecosystems' health is still quite unclear because of the difficulty in obtaining in situ data, especially in remote areas, like the southern ocean (so). southern elephant seals (mirounga leonina) proved to be a relevant alternative to the traditional oceanographic platforms to measure physica ... | 2015 | 26200780 |
| morphology of the tympanic-basicranial region in mirounga leonina (phocidae, carnivora), postnatal ontogeny and sexual dimorphism. | the auditory region of pinnipeds has seldom been described. here we describe and analyze the ontogenetic trajectory of the tympanic bulla of the southern elephant seal, mirounga leonina (phocidae, mammalia). this species is extremely sexually dimorphic and highly polygynous (organized in harems). we examined 118 specimens, arranged in three age classes (ci, cii, and ciii), ranging from newborn to adults (males and females). to analyze the overall size and shape of the tympanic bulla we performed ... | 2015 | 25827162 |
| long-range paternal gene flow in the southern elephant seal. | | 2003 | 12560542 |
| new insights into the cardiorespiratory physiology of weaned southern elephant seals (mirounga leonina). | southern elephant seal (mirounga leonina) pups must strike a balance between conserving energy during their post-weaning fast and simultaneously developing diving abilities to attain nutritional independence. little is known about environmental influences on cardiorespiratory patterns, hence energy use, throughout the 6 week fast. continuous heart rates were recorded for free-ranging, newly weaned southern elephant seals using heart rate time-depth recorders for 5-9 days at sub-antarctic macquar ... | 2015 | 27293733 |
| estimating trans-seasonal variability in water column biomass for a highly migratory, deep diving predator. | the deployment of animal-borne electronic tags is revolutionizing our understanding of how pelagic species respond to their environment by providing in situ oceanographic information such as temperature, salinity, and light measurements. these tags, deployed on pelagic animals, provide data that can be used to study the ecological context of their foraging behaviour and surrounding environment. satellite-derived measures of ocean colour reveal temporal and spatial variability of surface chloroph ... | 2014 | 25427104 |
| genetic and morphometric differentiation between island and mainland southern elephant seal populations. | we compare genetic (both nuclear and mitochondrial) and morphometric measures between two putative populations of southern elephant seal (mirounga leonina), and interpret the results in the context of data from mark-recapture and satellite-telemetric studies. one population is on the argentine mainland, while the other is 2,400 km away on south georgia island. we found pronounced differentiation at the mitochondrial dna (mtdna) control region that was distinct from the pattern of variation seen ... | 2001 | 11217905 |
| variation in body condition during the post-moult foraging trip of southern elephant seals and its consequences on diving behaviour. | mature female southern elephant seals (mirounga leonina) come ashore only in october to breed and in january to moult, spending the rest of the year foraging at sea. mature females may lose as much as 50% of their body mass, mostly in lipid stores, during the breeding season due to fasting and lactation. when departing to sea, post-breeding females are negatively buoyant, and the relative change in body condition (i.e. density) during the foraging trip has previously been assessed by monitoring ... | 2014 | 24803471 |
| metabolic limits on dive duration and swimming speed in the southern elephant seal mirounga leonina. | the ability of air-breathing marine predators to forage successfully depends on their ability to remain submerged. this is in turn related to their total o(2) stores and the rate at which these stores are used up while submerged. body size was positively related to dive duration in a sample of 34 adult female southern elephant seals from macquarie island. however, there was no relationship between body size and dive depth. this indicates that smaller seals, with smaller total o(2) stores, make s ... | 2006 | 11121352 |
| satellites, the all-seeing eyes in the sky: counting elephant seals from space. | regular censuses are fundamental for the management of animal populations but, are logistically challenging for species living in remote regions. the advent of readily accessible, high resolution satellite images of earth mean that it is possible to resolve relatively small (0.6 m) objects, sufficient to discern large animals. to illustrate how these advances can be used to count animals in remote regions, individual elephant seals (mirounga leonina) were counted using satellite imagery. we used ... | 2014 | 24651378 |
| bottom-up regulation of a pole-ward migratory predator population. | as the effects of regional climate change are most pronounced at polar latitudes, we might expect polar-ward migratory populations to respond as habitat suitability changes. the southern elephant seal (mirounga leonina l.) is a pole-ward migratory species whose populations have mostly stabilized or increased in the past decade, the one exception being the macquarie island population which has decreased continuously over the past 50 years. to explore probable causes of this anomalous trend, we co ... | 2014 | 24619437 |
| survivorship of a declining population of southern elephant seals, mirounga leonina, in relation to age, sex and cohort. | this study quantified both the age- and sex-specific survival rates of juveniles and adults, and tested for interannual differences in age-specific survival rates of the southern elephant seal population at marion island. pups were tagged on an annual basis from 1983 onwards at marion island, and a consistent recapture program yielded data that was analysed using the software package mark to obtain maximum-likelihood estimates of survival and capture probability. on average, 1st-year survival wa ... | 1999 | 28308560 |
| rapid increase in southern elephant seal genetic diversity after a founder event. | genetic diversity provides the raw material for populations to respond to changing environmental conditions. the evolution of diversity within populations is based on the accumulation of mutations and their retention or loss through selection and genetic drift, while migration can also introduce new variation. however, the extent to which population growth and sustained large population size can lead to rapid and significant increases in diversity has not been widely investigated. here, we asses ... | 2014 | 24478305 |
| heart rate, swimming speed, and estimated oxygen consumption of a free-ranging southern elephant seal. | heart rate, swimming speed, and diving behaviour were recorded simultaneously for an adult female southern elephant seal during her postbreeding period at sea with a wildlife computers heart-rate time depth recorder and a velocity time depth recorder. the errors associated with data storage versus real-time data collection of these data were analysed and indicated that for events of short duration (i.e., less than 10 min or 20 sampling intervals) serious biases occur. a simple model for estimati ... | 2006 | 9472815 |
| a southern indian ocean database of hydrographic profiles obtained with instrumented elephant seals. | the instrumentation of southern elephant seals with satellite-linked ctd tags has offered unique temporal and spatial coverage of the southern indian ocean since 2004. this includes extensive data from the antarctic continental slope and shelf regions during the winter months, which is outside the conventional areas of argo autonomous floats and ship-based studies. this landmark dataset of around 75,000 temperature and salinity profiles from 20-140 °e, concentrated on the sector between the kerg ... | 2014 | 25977785 |
| seasonal variation in vitamin d metabolites in southern elephant seal (mirounga leonina) females at south georgia. | southern elephant seals spend two periods on land each year, during breeding and moult, exposed to intensive uv radiation. the time between periods on land are spent at sea, with little exposure to the sun. a study of serum 25-oh-d3 and 1,25(oh)2-d3 on southern elephant seals was carried out at south georgia. samples were collected on four different occasions: early and late breeding, and early and late moult. the levels of 25-oh-d3 increased when seals were on land, and decreased when at sea. t ... | 1996 | 8925429 |