| coronary blood flow and myocardial segment dimensions during simulated dives in seals. | three harbor seals phoca vitulina richardsi and five spotted seals phoca vitulina largha were used in studies of acute episodes of local myocardial ischemia in open-chest, anesthetized animals and of coronary blood flow and regional function as indicated by left ventricular segment dimensions during experimentally simulated dives of conscious, instrumented animals. we observed that seal myocardium, in which there are few coronary anastomoses, responded to brief local occlusion with prompt local ... | 1985 | 4073282 |
| amphibious hearing in spotted seals (phoca largha): underwater audiograms, aerial audiograms and critical ratio measurements. | spotted seals (phoca largha) inhabit arctic regions that are facing both rapid climate change and increasing industrialization. while little is known about their sensory capabilities, available knowledge suggests that spotted seals and other ice seals use sound to obtain information from the surrounding environment. to quantitatively assess their auditory capabilities, the hearing of two young spotted seals was tested using a psychophysical paradigm. absolute detection thresholds for tonal sound ... | 2014 | 24574387 |
| complete mitochondrial genome of the korean spotted seal phoca largha (mammalia, pinnipedia, phocidae): genetic differences between p. largha and phoca vitulina. | | 2009 | 19900058 |
| brain transcriptomes of harbor seals demonstrate gene expression patterns of animals undergoing a metabolic disease and a viral infection. | diseases of marine mammals can be difficult to diagnose because of their life history and protected status. stranded marine mammals have been a particularly useful resource to discover and comprehend the diseases that plague these top predators. additionally, advancements in high-throughput sequencing (hts) has contributed to the discovery of novel pathogens in marine mammals. in this study, we use a combination of hts and stranded harbor seals (phoca vitulina) to better understand a known and u ... | 2016 | 28028481 |
| leveraging constraints and biotelemetry data to pinpoint repetitively used spatial features. | satellite telemetry devices collect valuable information concerning the sites visited by animals, including the location of central places like dens, nests, rookeries, or haul-outs. existing methods for estimating the location of central places from telemetry data require user-specified thresholds and ignore common nuances like measurement error. we present a fully model-based approach for locating central places from telemetry data that accounts for multiple sources of uncertainty and uses all ... | 2017 | 27935016 |
| usefulness of serum cardiac troponin i concentration as a marker of survival of harbor seal (phoca vitulina) pups during rehabilitation. | objective to measure serum cardiac troponin i (ctni) concentrations in orphaned harbor seal (phoca vitulina) pups at various points during rehabilitation in a seal rescue center and determine whether ctni concentration was associated with survival during rehabilitation and duration of rehabilitation. design serial cross-sectional study. animals fifty-five 2- to 9-day-old harbor seal pups. procedures blood samples for serum ctni concentration measurement, cbc, and serum biochemical analysis were ... | 2016 | 27901450 |
| dynamic habitat corridors for marine predators; intensive use of a coastal channel by harbour seals is modulated by tidal currents. | previous studies have found that predators utilise habitat corridors to ambush prey moving through them. in the marine environment, coastal channels effectively act as habitat corridors for prey movements, and sightings of predators in such areas suggest that they may target these for foraging. unlike terrestrial systems where the underlying habitat structure is generally static, corridors in marine systems are in episodic flux due to water movements created by tidal processes. although these hy ... | 2016 | 27881896 |
| avoidance of wind farms by harbour seals is limited to pile driving activities. | as part of global efforts to reduce dependence on carbon-based energy sources there has been a rapid increase in the installation of renewable energy devices. the installation and operation of these devices can result in conflicts with wildlife. in the marine environment, mammals may avoid wind farms that are under construction or operating. such avoidance may lead to more time spent travelling or displacement from key habitats. a paucity of data on at-sea movements of marine mammals around wind ... | 2016 | 27867217 |
| quantification and analysis of icebergs in a tidewater glacier fjord using an object-based approach. | tidewater glaciers are glaciers that terminate in, and calve icebergs into, the ocean. in addition to the influence that tidewater glaciers have on physical and chemical oceanography, floating icebergs serve as habitat for marine animals such as harbor seals (phoca vitulina richardii). the availability and spatial distribution of glacier ice in the fjords is likely a key environmental variable that influences the abundance and distribution of selected marine mammals; however, the amount of ice a ... | 2016 | 27828967 |
| aerial low-frequency hearing in captive and free-ranging harbour seals (phoca vitulina) measured using auditory brainstem responses. | the hearing sensitivity of 18 free-ranging and 10 captive harbour seals (phoca vitulina) to aerial sounds was measured in the presence of typical environmental noise through auditory brainstem response measurements. a focus was put on the comparative hearing sensitivity at low frequencies. low- and mid-frequency thresholds appeared to be elevated in both captive and free-ranging seals, but this is likely due to masking effects and limitations of the methodology used. the data also showed individ ... | 2016 | 27796483 |
| harbour seals (phoca vitulina) are able to time precisely. | time along with space is one of the two fundamental dimensions of life. whereas spatial aspects have been considered in experiments with marine mammals, research has so far not focused on timing per se although it is most likely involved in many behaviours such as foraging or navigation. this study investigated whether harbour seals possess a sense of time and how precisely they are able to discriminate time intervals. experiments took place in a chamber that allowed keeping ambient illumination ... | 2016 | 27496205 |
| conjoined fetal twins in a harbor seal (phoca vitulina). | in july 2013, a stranded harbor seal (phoca vitulina) died giving birth to conjoined fetuses. the twins were joined at the abdomen and thoracolumbar spine with the vertebral axis at 180°. the cause of this unique anomaly--a first for this species--was not identified. | 2016 | 26528575 |
| phenomenal advanced age of pupping in a captive pacific harbor seal (phoca vitulina richardsi). | to better define the life history in the captive environment, we describe the reproductive history and advanced age of pupping of a female pacific harbor seal (phoca vitulina richardsi) at the henry vilas zoo (hvz) in madison, wisconsin. this female gave birth to a viable pup on may 16, 2012, at the age of 42 years and is the oldest documented birth reported for this species. this female also demonstrated high temporal fidelity to her previously described birth timing. the pup's sire was also 42 ... | 2015 | 26452165 |
| absence of selenium protection against methylmercury toxicity in harbour seal leucocytes in vitro. | previous studies described high concentrations of mercury (hg) and selenium (se) in the blood of harbour seals, phoca vitulina from the north sea. in the present study, we evaluated the in vitro potential protective effects of sodium selenite (na2seo3) and selenomethionine (semet) on cell proliferation of harbour seal lymphocytes exposed to mehgcl 0.75μm. in vitro exposure of cona-stimulated t lymphocytes resulted in severe inhibition of dna synthesis, likely linked to severe loss of mitochondri ... | 2016 | 27197766 |
| comparative analysis of the fecal bacterial community of five harbor seals (phoca vitulina). | the gut microbiota has many beneficial effects on host metabolism and health, and its composition is determined by numerous factors. it is also assumed that there was a co-evolution of mammals and the bacteria inhabiting their gut. current knowledge of the mammalian gut microbiota mainly derives from studies on humans and terrestrial animals, whereas those on marine mammals are sparse. however, they could provide additional information on influencing factors, such as the role of diet and co-evol ... | 2016 | 27734626 |
| quantitative classification of harbor seal breeding calls in georgia strait, canada. | during breeding season, male harbor seals (phoca vitulina) produce underwater calls used in sexual competition and advertisement. call characteristics vary among populations, and within-population differences are thought to represent individual variation. however, vocalizations have not been described for several populations of this widely-distributed and genetically diverse species. this study describes the vocal repertoire of harbor seals from british columbia, canada. underwater recordings we ... | 2016 | 27586756 |
| development of an artificial sensor for hydrodynamic detection inspired by a seal's whisker array. | nature has shaped effective biological sensory systems to receive complex stimuli generated by organisms moving through water. similar abilities have not yet been fully developed in artificial systems for underwater detection and monitoring, but such technology would enable valuable applications for military, commercial, and scientific use. we set out to design a fluid motion sensor array inspired by the searching performance of seals, which use their whiskers to find and follow underwater wakes ... | 2016 | 27580063 |
| polychlorinated biphenyl-related alterations of the expression of essential genes in harbour seals (phoca vitulina) from coastal sites in canada and the united states. | as long-lived marine mammals found throughout the temperate coastal waters of the north pacific and atlantic oceans, harbour seals (phoca vitulina) have become an invaluable sentinel of food-web contamination. their relatively high trophic position predisposes harbour seals to the accumulation of harmful levels of persistent organic pollutants (pops). we obtained skin/blubber biopsy samples from live-captured young harbour seals from various sites in the northeastern pacific (british columbia, c ... | 2017 | 28528409 |
| source levels and call parameters of harbor seal breeding vocalizations near a terrestrial haulout site in glacier bay national park and preserve. | source levels of harbor seal breeding vocalizations were estimated using a three-element planar hydrophone array near the beardslee islands in glacier bay national park and preserve, alaska. the average source level for these calls was 144 dbrms re 1 μpa at 1 m in the 40-500 hz frequency band. source level estimates ranged from 129 to 149 dbrms re 1 μpa. four call parameters, including minimum frequency, peak frequency, total duration, and pulse duration, were also measured. these measurements i ... | 2017 | 28372144 |
| seasonal variation of harbor seal's diet from the wadden sea in relation to prey availability. | the wadden sea has an important role for marine mammals in terms of resting, nursing and foraging. harbor seal is the most abundant marine mammal species in this area. the use of the food resources of the wadden sea by seals is not clear, and previous studies showed that this species can travel kilometers away from their haul-outs to forage in the north sea. in this study, we analyzed the stable isotopes of vibrissae from 23 dead harbor seals found on the island of sylt to investigate their diet ... | 2016 | 27176227 |
| seasonal variation in harbour seal (phoca vitulina) blubber cortisol - a novel indicator of physiological state? | cortisol is one of the main glucocorticoid hormones involved in both the mammalian stress response, and in fat metabolism and energy regulation, making it of increasing interest as a biomarker for stress, health and overall physiological state. however, transient stress responses to animal handling and sampling may be important sources of measurement artefact when investigating circulating concentrations of this hormone in wildlife. here, cortisol concentrations were measured in the plasma and, ... | 2016 | 26906193 |
| correction: brain meta-transcriptomics from harbor seals to infer the role of the microbiome and virome in a stranding event. | [this corrects the article doi: 10.1371/journal.pone.0143944.]. | 2015 | 26713443 |
| quantitative dna metabarcoding: improved estimates of species proportional biomass using correction factors derived from control material. | dna metabarcoding is a powerful new tool allowing characterization of species assemblages using high-throughput amplicon sequencing. the utility of dna metabarcoding for quantifying relative species abundances is currently limited by both biological and technical biases which influence sequence read counts. we tested the idea of sequencing 50/50 mixtures of target species and a control species in order to generate relative correction factors (rcfs) that account for multiple sources of bias and a ... | 2016 | 26602877 |
| treatment of naturally acquired demodectic mange with amitraz in two harbour seals (phoca vitulina). | two male harbour seals (phoca vitulina; 33 and 35 years old, respectively), housed since 2002 at a zoo for exhibition purposes, developed severe, multifocal and diffuse skin lesions. skin scrapings and microscopy for parasites as well as pure cultures for bacteria and dermatophytes were carried out to identify the aetiological agent. skin scrapings showed that lesions appearing on the seals were caused by an infestation of demodex mites, which is uncommon in marine mammals, and were not due to o ... | 2015 | 26551425 |
| aphakic phacoemulsification and automated anterior vitrectomy, and postreturn monitoring of a rehabilitated harbor seal (phoca vitulina richardsi) pup. | a female harbor seal pup rescued along the coast of san diego on 13 june 2012 was diagnosed with bilateral mature cataracts, apparently congenital, in association with vitreal herniation in the anterior chamber of each eye. the cataracts were surgically removed on 1 august 2012 with single-port aphakic phacoemulsification and automated anterior vitrectomy. postoperative monitoring during the next several weeks indicated that vision had been functionally repaired and that she could visually orien ... | 2015 | 26352980 |
| xenobiotic and immune-relevant molecular biomarkers in harbor seals as proxies for pollutant burden and effects. | harbor seals are exposed to increasing pressure caused by anthropogenic activities in their marine environment. persistent organic pollutants (pops) and trace elements are hazardous contaminants that accumulate in tissues of harbor seals. pops and trace elements can negatively affect the immune-system and have been reported, e.g., to increase susceptibility to viral infections in seals. biomarkers of the xenobiotic metabolism, cytokines, and heat-shock protein as cell mediators of the immune-sys ... | 2016 | 26296438 |
| effects of methylmercury on harbour seal peripheral blood leucocytes in vitro studied by electron microscopy. | methylmercury (mehg) is highly immunotoxic and can alter the health status of the harbour seal, phoca vitulina, from the north sea. to investigate the mechanism of mehg-induced toxicity in harbour seal lymphocytes, concanavalin a (cona)-stimulated peripheral blood leucocytes were exposed in vitro to sublethal concentrations of mehgcl (0.2, 1, and 2 µm) for 72 h and then analysed for their viability and ultrastructure. after 72 h of incubation, cells were counted with a propidium iodide staining ... | 2016 | 26264045 |
| essential and toxic elements in blood samples of harbor seals (phoca vitulina) from the islands helgoland (north sea) and anholt (baltic sea): a comparison study with urbanized areas. | the harbor seals (phoca vitulina) from helgoland (north sea) and anholt (kattegat, baltic sea) are top predators within the marine food web and an indicator species of the environmental contamination. furthermore, they are a main tourist attraction. despite these important roles, little is known about the health and pollutant contamination of these seals. the objective of this study was therefore to investigate 18 essential and nonessential/toxic elements (al, as, be, ca, cr, cu, fe, k, mn, mo, ... | 2016 | 26253942 |
| seasonal, oceanographic and atmospheric drivers of diving behaviour in a temperate seal species living in the high arctic. | the harbour seal (phoca vitulina) population in svalbard marks the northernmost limit of the species' range. this small population experiences environmental extremes in sea and air temperatures, sea ice cover and also in light regime for this normally temperate species. this study deployed conductivity temperature depth satellite relay data loggers (ctd-srdls) on 30 adult and juvenile harbour seals in 2009 and 2010 to study their foraging behaviour across multiple seasons. a total of 189,104 div ... | 2015 | 26196289 |
| characterization of seal whisker morphology: implications for whisker-inspired flow control applications. | seals with beaded whiskers, that is the majority of true seals (phocids), are able to trace even minute disturbance caused by prey fish in the ambient flow using only sensory input from their whiskers. the unique three-dimensional undulating morphology of seal whiskers has been associated with their capability of suppressing vortex-induced vibration and reducing drag. the exceptional hydrodynamic traits of seal whiskers are of great interest in renovating the design of aero-propulsion flow ... | 2017 | 28840853 |
| epitheliotropic intestinal t-cell lymphoma in a harbor seal (phoca vitulina). | a 14-yr- old, male harbor seal ( phoca vitulina ) presented with depression, anorexia, and weight loss. clinical examination revealed no specific abnormalities. diagnostic imaging displayed an enlarged mass in the dorso-cranial abdomen. the animal was euthanized due to progressive worsening of symptoms. grossly, severe emaciation and a massive enlargement of one mesenteric lymph node were found. microscopically, a neoplastic round cell population with morphologic characteristics of mature lympho ... | 2017 | 28749269 |
| contaminant levels in the world's northernmost harbor seals (phoca vitulina). | the world's northernmost harbor seal (phoca vitulina) population, which inhabits svalbard, norway, constitutes a genetically distinct population. the present study reports concentrations of 14 pcbs, 5 chlordanes, p,p'-ddt, p,p'-dde, hexachlorobenzene (hcb), mirex, and, α-, β-and γ-hexachlorocyclohexane (hch) in blubber, and pentachlorophenol, 4-oh-heptachlorostyrene, 10 oh-pcbs and 14 perfluoroalkyl substances in plasma of live-captured harbor seals from this population (4 males, 4 females, 4 ju ... | 2014 | 25152181 |
| hydrodynamic sensory threshold in harbour seals (phoca vitulina) for artificial flatfish breathing currents. | harbour seals have the ability to detect benthic fish such as flatfish using the water currents these fish emit through their gills (breathing currents). we investigated the sensory threshold in harbour seals for this specific hydrodynamic stimulus under conditions which are realistic for seals hunting in the wild. we used an experimental platform where an artificial breathing current was emitted through one of eight different nozzles. two seals were trained to search for the active nozzle. each ... | 2017 | 28679792 |
| intraperitoneal implantation of life-long telemetry transmitters in three rehabilitated harbor seal pups. | pinnipeds, including many phocid species of concern, are inaccessible and difficult to monitor for extended periods using conventional, externally attached telemetry devices that are shed during the annual molt. archival satellite transmitters were implanted intraperitoneally into three stranded pacific harbor seal pups (phoca vitulina richardii) that completed rehabilitation, to evaluate the viability of this surgical technique for the deployment of life long telemetry devices in phocids. the l ... | 2017 | 28545460 |
| spatially estimating disturbance of harbor seals (phoca vitulina). | tidewater glacial fjords in alaska provide habitat for some of the largest aggregations of harbor seals (phoca vitulina), with calved ice serving as platforms for birthing and nursing pups, molting, and resting. these fjords have also been popular destinations for tour ships for more than a century, with dramatic increases in vessel traffic since the 1980s. seals on ice are known to flush into the water when approached by tour ships, but estimating the exposure to disturbance across populations ... | 2015 | 26132083 |
| options for modulating intra-specific competition in colonial pinnipeds: the case of harbour seals (phoca vitulina) in the wadden sea. | colonial pinnipeds may be subject to substantial consumptive competition because they are large, slow-moving central place foragers. we examined possible mechanisms for reducing this competition by examining the diving behaviour of harbour seals (phoca vitulina) after equipping 34 seals (11 females, 23 males) foraging from three locations; rømø, denmark and lorenzenplate and helgoland, germany, in the wadden sea area with time-depth recorders. analysis of 319,021 dives revealed little between-co ... | 2015 | 26082869 |
| temporal and spatial variation in harbor seal (phoca vitulina l.) roar calls from southern scandinavia. | male harbor seals gather around breeding sites for competitive mating displays. here, they produce underwater vocalizations possibly to attract females and/or scare off other males. these calls offer prospects for passive acoustic monitoring. acoustic monitoring requires a good understanding of natural variation in calling behavior both temporally and among geographically separate sites. such variation in call structure and calling patterns were studied in harbor seal vocalizations recorded at t ... | 2017 | 28372059 |
| immunotoxic effects of single and combined pharmaceuticals exposure on a harbor seal (phoca vitulina) b lymphoma cell line. | the potential risk of pharmaceuticals in the environment to top-predators is still largely unknown. in this study, we assessed the immunotoxic effects of ten pharmaceuticals individually and as mixtures on a harbor seal (phoca vitulina) b lymphoma cell line. a significant reduction in lymphocyte transformation was observed following an exposure to 12,500μg/l 17α-ethinyl estradiol and 25,000μg/l naproxen. exposure to 12,500μg/l 17α-ethinyl estradiol decreased the percentage of cell in the g0/g1 p ... | 2017 | 28262249 |
| saccadic movement strategy in a semiaquatic species - the harbour seal (phoca vitulina). | moving animals can estimate the distance of visual objects from image shift on their retina (optic flow) created during translational, but not rotational movements. to facilitate this distance estimation, many terrestrial and flying animals perform saccadic movements, thereby temporally separating translational and rotational movements, keeping rotation times short. in this study, we analysed whether a semiaquatic mammal, the harbour seal, also adopts a saccadic movement strategy. we recorded th ... | 2017 | 28167803 |
| from sediment to top predators: broad exposure of polyhalogenated carbazoles in san francisco bay (u.s.a.). | the present study provides the first comprehensive investigation of polyhalogenated carbazoles (phczs) contamination in an aquatic ecosystem. phczs have been found in soil and aquatic sediment from several different regions, but knowledge of their bioaccumulation and trophodynamics is extremely scarce. this work investigated a suite of 11 phcz congeners in san francisco bay (united states) sediment and organisms, including bivalves (n = 6 composites), sport fish (n = 12 composites), harbor seal ... | 2017 | 28112952 |
| saccadic movement strategy in common cuttlefish (sepia officinalis). | most moving animals segregate their locomotion trajectories in short burst like rotations and prolonged translations, to enhance distance information from optic flow, as only translational, but not rotational optic flow holds distance information. underwater, optic flow is a valuable source of information as it is in the terrestrial habitat, however, so far, it has gained only little attention. to extend the knowledge on underwater optic flow perception and use, we filmed the movement pattern of ... | 2016 | 28105017 |
| hydrodynamic detection and localization of artificial flatfish breathing currents by harbour seals (phoca vitulina). | harbour seals are known to be opportunistic feeders, whose diet consists mainly of pelagic and benthic fish, such as flatfish. as flatfish are often cryptic and do not produce noise, we hypothesized that harbour seals are able to detect and localize flatfish using their hydrodynamic sensory system (vibrissae), as fish emit water currents through their gill openings (breathing currents). to test this hypothesis, we created an experimental platform where an artificial breathing current was emitted ... | 2017 | 28100802 |
| underwater sound localization of pure tones in the median plane by harbor seals (phoca vitulina). | in an underwater environment the physical characteristics of sound propagation differ considerably from those in air. for this reason, sound localization underwater is associated with difficulties, especially in the median plane. it was the approach of the present study to investigate whether harbor seals (phoca vitulina) are able to determine the direction of a tonal signal form above or below in the underwater environment. minimum audible angles (maas) or the angular range in which the animals ... | 2016 | 28040008 |
| diving related changes in the blood oxygen stores of rehabilitating harbor seal pups (phoca vitulina). | harbor seal (phoca vitulina) pups begin diving within hours of birth, stimulating the development of the blood oxygen (o2) stores necessary to sustain underwater aerobic metabolism. since harbor seals experience a brief nursing period, the early-life development of these blood o2 stores is necessary for successful post-weaning foraging. if mothers and pups become prematurely separated, the pup may be transported to a wildlife rehabilitation center for care. previous studies suggest that the shal ... | 2015 | 26061662 |
| animal movement constraints improve resource selection inference in the presence of telemetry error. | multiple factors complicate the analysis of animal telemetry location data. recent advancements address issues such as temporal autocorrelation and telemetry measurement error, but additional challenges remain. difficulties introduced by complicated error structures or barriers to animal movement can weaken inference. we propose an approach for obtaining resource selection inference from animal location data that accounts for complicated error structures, movement constraints, and temporally aut ... | 2015 | 26649380 |
| multiple-pulse sounds and seals: results of a harbor seal (phoca vitulina) telemetry study during wind farm construction. | offshore construction and survey techniques can produce pulsed sounds with a high sound pressure level. in coastal waters, the areas in which they are produced are often also used by seals, potentially resulting in auditory damage or behavioral avoidance. here, we describe a study on harbor seals during a wind farm installation off southeast england. the study used gps/global system for mobile communication tags on 23 harbor seals that provided distribution and activity data; the closest range o ... | 2016 | 26610987 |
| factors affecting haul-out behavior of harbor seals (phoca vitulina) in tidewater glacier inlets in alaska: can tourism vessels and seals coexist? | large numbers of harbor seals (phoca vitulina) use habitat in tidewater glaciers in alaska for pupping, breeding, and molting. glacial fjords are also popular tourist destinations; however, visitation by numerous vessels can result in disturbance of seals during critical life-history phases. we explored factors affecting haul-out behavior of harbor seals at a glacial site frequented by tourism vessels. in 2008-10, we deployed vhf transmitters on 107 seals in endicott arm, alaska. we remotely mon ... | 2015 | 26017404 |
| dental and temporomandibular joint pathology of the eastern pacific harbour seal (phoca vitulina richardii). | skulls from 214 eastern pacific harbour seals (phoca vitulina richardii) were examined macroscopically according to predefined criteria. the museum specimens were acquired from strandings along the west coast of the usa between 1909 and 2014. ninety-eight skulls (45.8%) were from male animals, 108 (50.5%) from female animals and eight (3.7%) from animals of unknown sex. their age varied from neonate to adult, with 101 adult animals (47.2%), 93 juvenile animals (43.5%) and 20 neonatal animals (9. ... | 2015 | 25824118 |
| blood and hair mercury concentrations in the pacific harbor seal (phoca vitulina richardii) pup: associations with neurodevelopmental outcomes. | monomethylmercury (mehg(+)) is an environmental pollutant, which at sufficiently high exposures, has induced neurotoxicosis in several animal species, including humans. adverse neurological effects due to gestational exposure are of particular concern as mehg(+) readily crosses the blood-brain and placental barriers. the degree to which environmental concentrations in marine prey affect free-living piscivorous wildlife, however, remains largely undetermined. we examined associations of gestation ... | 2015 | 25814195 |
| detection and effects of harmful algal toxins in scottish harbour seals and potential links to population decline. | over the past 15 years or so, several scottish harbour seal (phoca vitulina) populations have declined in abundance and several factors have been considered as possible causes, including toxins from harmful algae. here we explore whether a link could be established between two groups of toxins, domoic acid (da) and saxitoxins (stxs), and the decline in the harbour seal populations in scotland. we document the first evidence that harbour seals are exposed to both da and stxs from consuming contam ... | 2015 | 25666120 |
| unique fur and skin structure in harbour seals (phoca vitulina)--thermal insulation, drag reduction, or both? | vertebrate surface structures, including mammalian skin and hair structures, have undergone various modifications during evolution in accordance with functional specializations. harbour seals rely on their vibrissal system for orientation and foraging. to maintain tactile sensitivity even at low temperatures, the vibrissal follicles are heated up intensely, which could cause severe heat loss to the environment. we analysed skin samples of different body parts of harbour seals, and expected to se ... | 2015 | 25652462 |
| sensitivity of a harbor seal (phoca vitulina) to coherent visual motion in random dot displays. | motion vision is one of the fundamental properties of the visual system and is involved in numerous tasks. previous work has shown that harbor seals are able to perceive visual motion. tying in with this experimental finding, we assessed the sensitivity of harbor seals to visual motion using random dot displays. in these random dot displays, either all or a percentage of the dots plotted in the display area move into one direction which is referred to as percent coherence. using random dot displ ... | 2014 | 25520911 |
| esophageal squamous cell carcinoma in six harbor seals (phoca vitulina spp.). | six cases of esophageal squamous cell carcinoma were identified in six captive adult pacific (phoca vitulina richardsii; n = 2) and atlantic (phoca vitulina concolor; n = 4) harbor seals. these seals presented with intermittent dysphagia, regurgitation, inappetence, and abnormal posturing. common clinical pathology findings in these seals included azotemia, hyperproteinemia, hyperglobulinemia, and leukocytosis. gastrointestinal endoscopy commonly revealed an ulcerated mass near the gastroesophag ... | 2014 | 25314830 |
| effects and risk evaluation of oil spillage in the sea areas of changxing island. | this paper evaluated the oil spillage risk in the waters near the island of changxing in dalian (china) based on the established risk assessment index. four wind regimes (windless, northerly wind, westerly wind and southerly wind) were selected as weather conditions for the dynamic prediction of oil drift. if an oil spill occurs near the koumen (a place near the island of changxing), the forecast and evaluation are conducted based on a three-dimensional mathematical model of oil spillage, and th ... | 2014 | 25153473 |
| harbor seals (phoca vitulina) can perceive optic flow under water. | optic flow, the pattern of apparent motion elicited on the retina during movement, has been demonstrated to be widely used by animals living in the aerial habitat, whereas underwater optic flow has not been intensively studied so far. however optic flow would also provide aquatic animals with valuable information about their own movement relative to the environment; even under conditions in which vision is generally thought to be drastically impaired, e. g. in turbid waters. here, we tested unde ... | 2014 | 25058490 |
| length of intervals between epidemics: evaluating the influence of maternal transfer of immunity. | the length of intervals between epidemic outbreaks of infectious diseases is critical in epidemiology. in several species of marine mammals and birds, it is pivotal to also consider the life history of the species of concern, as the contact rate between individuals can have a seasonal flux, for example, due to aggregations during the breeding season. recently, particular interest has been given to the role of the dynamics of immunity in determining the intervals between epidemics in wild animal ... | 2014 | 25035798 |
| methoxylated pbdes (meo-pbdes), hydroxylated pbdes (ho-pbdes) and hydroxylated pcbs (ho-pcbs) in the liver of harbor seals from the northwest atlantic. | metabolites of pcbs and pbdes are shown to influence the thyroid hormone homeostasis and therefore, could have an influence on the growth of newborn or young animals. we have investigated the occurrence of hydroxylated pcbs (ho-pcbs), hydroxylated pbdes (ho-pbdes), and methoxylated pbdes (meo-pbdes) in the liver (48 pups; 6 adults) and blubber (4 pups; 1 adult) of harbor seals (phoca vitulina concolor) from the northwest atlantic. the sum of ho-pcbs in the liver ranged from 90 to 22,450 pg/g wet ... | 2014 | 24982026 |
| polychlorinated biphenyls still pose significant health risks to northwest atlantic harbor seals. | polychlorinated biphenyls (pcbs) have been detected at relatively high concentrations in harbor seals, apex predators in the northwest atlantic. as part of an ongoing assessment of the effects of pcbs on population health, we analyzed tri- to deca-pcbs in the liver of 56 harbor seals (6 adult males, 50 pups) and in 11 blubber samples (4 adult males, 7 pups) and examined tissue-specific accumulation patterns, biomagnification potential, and toxic implications of current pcb concentrations. hepati ... | 2014 | 24875260 |
| mechanical characteristics of harbor seal (phoca vitulina) vibrissae under different circumstances and their implications on its sensing methodology. | in this paper, the mechanical properties of harbor seal vibrissae immersed in various solutions are investigated. as there are no nerves along the length of the vibrissae, all the perturbations have to be transmitted to their bases for sensing. hence, quantification and understanding of the mechanical properties of the vibrissae are essential in determining the perturbations transmitted to the base of the vibrissae. two experimental setups are devised for measurements of the different properties ... | 2014 | 24871073 |
| selenium and mercury concentrations in harbor seals (phoca vitulina) from central california: health implications in an urbanized estuary. | we measured total selenium and total mercury concentrations ([tse] and [thg]) in hair (n=138) and blood (n=73) of harbor seals (phoca vitulina) from california to assess variation by geography and sex, and inferred feeding relationships based on carbon, nitrogen, and sulfur stable isotopes. harbor seals from hg-contaminated sites had significantly greater [thg], and lesser [tse] and tse:thg molar ratios than seals from a relatively uncontaminated site. males had significantly greater [thg] than ... | 2014 | 24823685 |
| what a jerk: prey engulfment revealed by high-rate, super-cranial accelerometry on a harbour seal (phoca vitulina). | a key component in understanding the ecological role of marine mammal predators is to identify how and where they capture prey in time and space. satellite and archival tags on pinnipeds generally only provide diving and position information, and foraging is often inferred to take place in particular shaped dives or when the animal remains in an area for an extended interval. however, fast movements of the head and jaws may provide reliable feeding cues that can be detected by small low-power ac ... | 2014 | 24737765 |
| plastic ingestion by harbour seals (phoca vitulina) in the netherlands. | abundance of ingested debris by seals has been mentioned as a potential indicator of marine litter in the european marine strategy framework directive (msfd). a sample of 107 stomachs, 100 intestines and 125 scats of harbour seals from the netherlands was analysed for the presence of plastics. incidence of plastic was 11% for stomachs, 1% for intestines, and 0% for scats. younger animals, up to 3 years of age, were most affected. this is the first quantitative study of plastic ingestion by phoci ... | 2013 | 23245459 |
| are harbour seals (phoca vitulina) able to perceive and use polarised light? | harbour seals are active at night and during the day and see well in both air and water. polarised light, which is a well-known visual cue for orientation, navigation and foraging, is richly available in harbour seal habitats, both above and below the water surface. we hypothesised that an ability to detect and use polarised light could be valuable for seals, and thus tested if they are able to see this property of light. we performed two behavioural experiments, one involving object discriminat ... | 2013 | 23076442 |
| fine-scale variability in harbor seal foraging behavior. | understanding the variability of foraging behavior within a population of predators is important for determining their role in the ecosystem and how they may respond to future ecosystem changes. however, such variability has seldom been studied in harbor seals on a fine spatial scale (<30 km). we used a combination of standard and bayesian generalized linear mixed models to explore how environmental variables influenced the dive behavior of harbor seals. time-depth recorders were deployed on har ... | 2014 | 24717815 |
| stomach temperature records reveal nursing behaviour and transition to solid food consumption in an unweaned mammal, the harbour seal pup (phoca vitulina). | knowledge of milk transfer from mother to offspring and early solid food ingestions in mammals allows for a greater understanding of the factors affecting transition to nutritional independence and pre-weaning growth and survival. yet studies monitoring suckling behaviour have often relied on visual observations, which might not accurately represent milk intake. we assessed the use of stomach temperature telemetry to monitor suckling and foraging behaviour in free-ranging harbour seal (phoca vit ... | 2014 | 24587327 |
| high-throughput sequencing reveals inbreeding depression in a natural population. | proxy measures of genome-wide heterozygosity based on approximately 10 microsatellites have been used to uncover heterozygosity fitness correlations (hfcs) for a wealth of important fitness traits in natural populations. however, effect sizes are typically very small and the underlying mechanisms remain contentious, as a handful of markers usually provides little power to detect inbreeding. we therefore used restriction site associated dna (rad) sequencing to accurately estimate genome-wide hete ... | 2014 | 24586051 |
| feeding kinematics, suction, and hydraulic jetting performance of harbor seals (phoca vitulina). | the feeding kinematics, suction and hydraulic jetting capabilities of captive harbor seals (phoca vitulina) were characterized during controlled feeding trials. feeding trials were conducted using a feeding apparatus that allowed a choice between biting and suction, but also presented food that could be ingested only by suction. subambient pressure exerted during suction feeding behaviors was directly measured using pressure transducers. the mean feeding cycle duration for suction-feeding events ... | 2014 | 24475170 |
| biomagnification of polychlorinated biphenyls in a harbor seal (phoca vitulina) food web from the strait of georgia, british columbia, canada. | polychlorinated biphenyl (pcb) biomagnification was characterized in a harbor seal food web in the strait of georgia, british columbia, canada. trophic magnification factors (tmfs) for pcbs averaged 3.6, with a range of 0.7 to 9.4. the tmfs for individual congeners correlated with log k(ow) (r(2) = 0.56, p < 0.001), reflecting the role that physicochemical properties play in driving the biomagnification of pcbs in marine food webs. however, tmfs differed among pcb structure activity groups, clea ... | 2012 | 22847788 |
| haul-out behaviour of the world's northernmost population of harbour seals (phoca vitulina) throughout the year. | the harbour seal population in svalbard occurs at the northernmost limit of the species' range. it experiences environmental extremes far beyond the norm for this species, including an extended period of polar night and extensive sea ice cover. in 2009 and 2010, 60 harbour seals (30 pups + 30 immature/mature seals) from this population were equipped with satellite-relay data loggers (srdls) to study their haul-out behaviour, with a special focus on the winter period. using a combination of gener ... | 2014 | 24465867 |
| integrating genetic data and population viability analyses for the identification of harbour seal (phoca vitulina) populations and management units. | identification of populations and management units is an essential step in the study of natural systems. still, there is limited consensus regarding how to define populations and management units, and whether genetic methods allow for inference at the relevant spatial and temporal scale. here, we present a novel approach, integrating genetic, life history and demographic data to identify populations and management units in southern scandinavian harbour seals. first, 15 microsatellite markers and ... | 2014 | 24382213 |
| long distance movements and disjunct spatial use of harbor seals (phoca vitulina) in the inland waters of the pacific northwest. | worldwide, adult harbor seals (phoca vitulina) typically limit their movements and activity to <50 km from their primary haul-out site. as a result, the ecological impact of harbor seals is viewed as limited to relatively small spatial scales. harbor seals in the pacific northwest are believed to remain <30 km from their primary haul-out site, one of several contributing factors to the current stock designation. however, movement patterns within the region are not well understood because previou ... | 2012 | 22723925 |
| vibrissal sensitivity in a harbor seal (phoca vitulina). | prior efforts to characterize the capabilities of the vibrissal system in seals have yielded conflicting results. here, we measured the sensitivity of the vibrissal system of a harbor seal (phoca vitulina) to directly coupled sinusoidal stimuli delivered by a vibrating plate. a trained seal was tested in a psychophysical paradigm to determine the smallest velocity that was detectable at nine frequencies ranging from 10 to 1000 hz. the stimulus plate was driven by a vibration shaker and the veloc ... | 2015 | 26056243 |
| the intensity of horizontal and vertical search in a diving forager: the harbour seal. | free ranging foraging animals can vary their searching intensity in response to the profitability of the environment by modifying their movements. marine diving animals forage in a three dimensional space and searching intensity can be varied in both the horizontal and vertical planes. therefore understanding the relationship between the allocation of searching effort in these two spaces can provide a better understanding of searching strategies and a more robust identification of foraging behav ... | 2015 | 26019871 |
| improving accuracy of dna diet estimates using food tissue control materials and an evaluation of proxies for digestion bias. | ecologists are increasingly interested in quantifying consumer diets based on food dna in dietary samples and high-throughput sequencing of marker genes. it is tempting to assume that food dna sequence proportions recovered from diet samples are representative of consumer's diet proportions, despite the fact that captive feeding studies do not support that assumption. here, we examine the idea of sequencing control materials of known composition along with dietary samples in order to correct for ... | 2014 | 24102760 |
| clinical evaluation and biochemical analyses of thiamine deficiency in pacific harbor seals (phoca vitulina) maintained at a zoological facility. | to determine thiamine-dependent enzyme activities in various tissue samples of pacific harbor seals (phoca vitulina) and thiaminase activities in dietary fish. | 2013 | 24094267 |
| relationships between in vitro lymphoproliferative responses and levels of contaminants in blood of free-ranging adult harbour seals (phoca vitulina) from the north sea. | in vitro culture of peripheral blood leucocytes (pbls) is currently used in toxicological studies of marine mammals. however, blood cells of wild individuals are exposed in vivo to environmental contaminants before being isolated and exposed to contaminants in vitro. the aim of this study was to highlight potential relationships between blood contaminant levels and in vitro peripheral blood lymphocyte proliferation in free-ranging adult harbour seals (phoca vitulina) from the north sea. blood sa ... | 2013 | 24051082 |
| the effect of diet and feeding level on survival and weight gain of hand-raised harbor seal pups (phoca vitulina). | hundreds of stranded harbor seals pups (phoca vitulina) are brought to wildlife rescue centers every year. typical hand-rearing diets include artificial milk-replacers and diets based on macerated fish fed via gavage, but weight gains are often low and mortality rates can be high. this study compared survival and weight gain of orphaned seal pups fed either artificial milk-replacer or fish-formula. pups admitted to the facility in summer 2007 (n=145) and 2008 (n=98) were randomly assigned to one ... | 2011 | 21971911 |
| are metal-induced hypersensitivities in harbor seals associated with liver function? | environmental exposure to metals is believed to affect marine mammal health adversely including immunosuppression or acute as well as chronic inflammatory processes leading to hypersensitivities or autoimmune diseases. metal-specific hypersensitivities were found in several pinnipeds of the north sea. however, hypersensitivity is a complex phenomenon whose characteristics are still not completely understood; in particular, effects on health are not well established. in the present study, we comp ... | 2011 | 21723569 |
| state-space modelling reveals proximate causes of harbour seal population declines. | declines in large vertebrate populations are widespread but difficult to detect from monitoring data and hard to understand due to a multiplicity of plausible biological explanations. in parts of scotland, harbour seals (phoca vitulina) have been in decline for 10 years. to evaluate the contributions of different proximate causes (survival, fecundity, observation artefacts) to this decline, we collated behavioural, demographic and population data from one intensively studied population in part o ... | 2014 | 24036987 |
| hydrodynamic discrimination of wakes caused by objects of different size or shape in a harbour seal (phoca vitulina). | harbour seals can use their mystacial vibrissae to detect and track hydrodynamic wakes. we investigated the ability of a harbour seal to discriminate objects of different size or shape by their hydrodynamic signature and used particle image velocimetry to identify the hydrodynamic parameters that a seal may be using to do so. hydrodynamic trails were generated by different sized or shaped paddles that were moved in the calm water of an experimental box to produce a characteristic signal. in a tw ... | 2011 | 21562180 |
| immune-relevant and new xenobiotic molecular biomarkers to assess anthropogenic stress in seals. | harbour seals as top predators and indicators for ecosystem health are exposed to increasing pressure caused by anthropogenic activities in their marine environment. after their lactation period of about 24 days pups are weaned and left to hunt on their own. little is known about the development of their immune system and a better understanding of anthropogenic impacts on the general health and immune system of harbour seal pups is needed. mrna transcription of six immuno-relevant biomarkers was ... | 2013 | 24025588 |
| accumulation features of trace elements in mass-stranded harbor seals (phoca vitulina) in the north sea coast in 2002: the body distribution and association with growth and nutrition status. | body distribution and growth- and nutritional status-dependent accumulation of 21 trace elements were investigated in harbor seals (phoca vitulina) stranded in the north sea coast in 2002. higher concentrations and burdens of mn, se, mo, ag, sn, hg, and bi in the liver, cd in the kidney, as in the blubber, and co, sr, and ba in the bone were observed. significant positive correlations of hepatic se, mo, ag, cd, sn, hg, tl, and bi with standard body length were found, while significant negative r ... | 2011 | 21429529 |
| near-threshold equal-loudness contours for harbor seals (phoca vitulina) derived from reaction times during underwater audiometry: a preliminary study. | equal-loudness functions describe relationships between the frequencies of sounds and their perceived loudness. this pilot study investigated the possibility of deriving equal-loudness contours based on the assumption that sounds of equal perceived loudness elicit equal reaction times (rts). during a psychoacoustic underwater hearing study, the responses of two young female harbor seals to tonal signals between 0.125 and 100 khz were filmed. frame-by-frame analysis was used to quantify rt (the t ... | 2011 | 21303029 |
| congenital neuroglial heterotopia in a neonatal harbor seal (phoca vitulina richardsi ) with evidence of recent exposure to polycyclic aromatic hydrocarbons. | a male neonatal pacific harbor seal (phoca vitulina richardsi) stranded off the coast of california, usa, was presented for rehabilitation with numerous partially haired, soft tissue masses around the mouth and in the oropharynx. because of the extent of the lesions, the seal was humanely euthanized. histologically, the masses consisted of subepithelial connective tissue and subcutis expanded by a proliferation of streams and bundles of spindle to stellate cells. morphology of these cells sugges ... | 2011 | 21270017 |
| hearing thresholds of two harbor seals (phoca vitulina) for playbacks of multiple pile driving strike sounds. | pile driving, which creates high amplitude sounds with potentially negative impacts on the marine environment, is used to attach wind turbines to the sea bed. to quantify the distance at which pile driving sounds can be detected by harbor seals, unmasked hearing thresholds were obtained for series of five pile driving sounds recorded at 100 and 800 m from a pile driving location. the played back spectra resembled the spectra of sounds recorded under certain conditions 10-50 km from an offshore p ... | 2013 | 23967961 |
| immune status and function in harbor seal pups during the course of rehabilitation. | routine hematological and serum chemistry parameters are important tools for the evaluation of health and the treatment of marine mammals admitted to rehabilitation centers. the evaluation of phagocytosis, oxidative burst and immunoglobulin g (igg), as markers of immune system function, and haptoglobin (hp), as a stress marker, were evaluated alongside routine hematology and chemistry as potentially informative diagnostic tools for marine mammal health assessments. blood samples from harbor seal ... | 2013 | 23866720 |
| the world's northernmost harbour seal population-how many are there? | this study presents the first abundance estimate for the world's northernmost harbour seal (phoca vitulina) population, which resides in svalbard, norway, based on three digital stereoscopic photographic surveys conducted in 2009 and 2010. the counts from these high resolution 3d images were combined with a novel method for estimating correction factors for animals that were in the water at the time of the surveys, in which extensive behavioural data from radio-tagged harbour seals were used tog ... | 2013 | 23844035 |
| variation in breeding phenology provides insights into drivers of long-term population change in harbour seals. | phenological trends provide important indicators of environmental change and population dynamics. however, the use of untested population-level measures can lead to incorrect conclusions about phenological trends, particularly when changes in population structure or density are ignored. we used individual-based estimates of birth date and lactation duration of harbour seals (phoca vitulina) to investigate energetic consequences of changes in pupping phenology. using generalized linear mixed mode ... | 2013 | 23782881 |
| quantifying sequence proportions in a dna-based diet study using ion torrent amplicon sequencing: which counts count? | a goal of many environmental dna barcoding studies is to infer quantitative information about relative abundances of different taxa based on sequence read proportions generated by high-throughput sequencing. however, potential biases associated with this approach are only beginning to be examined. we sequenced dna amplified from faeces (scats) of captive harbour seals (phoca vitulina) to investigate whether sequence counts could be used to quantify the seals' diet. seals were fed fish in fixed p ... | 2013 | 23590207 |
| a harbor seal can transfer the same/different concept to new stimulus dimensions. | we investigated the formation of an abstract concept of same/different in a harbor seal by means of a two-item same/different task. stimuli were presented on a tft monitor. the subject was trained to respond according to whether two horizontally aligned white shapes presented on a black background were the same, or different from each other, by giving a no-go or go response. training comprised of four stages. first, the same/different task was trained with two shapes forming two same problems (a ... | 2013 | 23535852 |
| post-breeding season migrations of a top predator, the harbor seal (phoca vitulina richardii), from a marine protected area in alaska. | marine protected areas (mpas) are increasingly being used as a conservation tool for highly mobile marine vertebrates and the focus is typically on protecting breeding areas where individuals are aggregated seasonally. yet movements during the non-breeding season can overlap with threats that may be equally as important to population dynamics. thus understanding habitat use and movements of species during the non-breeding periods is critical for conservation. glacier bay national park, alaska, i ... | 2013 | 23457468 |
| vibrissal touch sensing in the harbor seal (phoca vitulina): how do seals judge size? | "whisker specialists" such as rats, shrews, and seals actively employ their whiskers to explore their environments and extract object properties such as size, shape, and texture. it has been suggested that whiskers could be used to discriminate between different sized objects in one of two ways: (i) to use whisker positions, such as angular position, spread or amplitude to approximate size; or (ii) to calculate the number of whiskers that contact an object. this study describes in detail how two ... | 2013 | 23397461 |
| assay dependence of brucella antibody prevalence in a declining alaskan harbor seal (phoca vitulina) population. | brucella is a group of bacteria that causes brucellosis, which can affect population health and reproductive success in many marine mammals. we investigated the serological prevalence of antibodies against brucella bacteria in a declining harbor seal population in glacier bay national park, alaska. | 2013 | 23324565 |
| hydrodynamic determination of the moving direction of an artificial fin by a harbour seal (phoca vitulina). | harbour seals can use their vibrissal system to detect and follow hydrodynamic trails left by moving objects. in this study we determined the maximum time after which a harbour seal could indicate the moving direction of an artificial fish tail and analysed the hydrodynamic parameters allowing the discrimination. hydrodynamic trails were generated using a fin-like paddle moving from left to right or from right to left in the calm water of an experimental box. the blindfolded seal was able to rec ... | 2010 | 20543117 |
| the effects of experimentally induced hyperthyroidism on the diving physiology of harbor seals (phoca vitulina). | many phocid seals are expert divers that remain submerged longer than expected based on estimates of oxygen storage and utilization. this discrepancy is most likely due to an overestimation of diving metabolic rate. during diving, a selective redistribution of blood flow occurs, which may result in reduced metabolism in the hypoperfused tissues and a possible decline in whole-body metabolism to below the resting level (hypometabolism). thyroid hormones are crucial in regulation of energy metabol ... | 2012 | 23060807 |
| hearing threshold shifts and recovery in harbor seals (phoca vitulina) after octave-band noise exposure at 4 khz. | safety criteria for underwater sounds from offshore pile driving are needed to protect marine mammals. as a first step toward understanding effects of impulsive sounds, two harbor seals were exposed to octave-band white noise centered at 4 khz at three mean received sound pressure levels (spls; 124, 136, and 148 db re 1 μpa) at up to six durations (7.5, 15, 30, 60, 120, and 240 min); mean received sound exposure level (sel) range was 166-190 db re 1 μpa(2) s. hearing thresholds were determined b ... | 2012 | 23039466 |
| temporal processing of low-frequency sounds by seals (l). | in a recent study, kastelein et al. [(2010) j. acoust. soc. am. 127, 1135-1145] reported auditory integration times for harbor seals (phoca vitulina) exceeding 3000 ms for 200 hz tonal signals. this finding is unexpected and potentially significant given that time constants measured in mammals for tones above 1 khz are typically less than 500 ms. to further explore this result, the hearing of another harbor seal was measured in air and water for 200 hz tones with durations of 500 and 2500 ms. th ... | 2012 | 23039406 |
| hair sampling location in harbor seals (phoca vitulina) affects selenium and mercury concentrations: implications for study design of trace element determination in pinnipeds. | hair is used to determine trace elements exposure and status of pinnipeds because it is an excretory route for many elements and can be collected non-lethally. despite increased use, there have been few studies on how sampling designs and procedures (e.g., hair type, collection site) affect results. the objective of this study was to determine whether concentrations of an essential (selenium; se) and non-essential element (mercury; hg) differed between hair samples collected from two body locati ... | 2012 | 23017952 |
| endocrine changes in harbor seal (phoca vitulina) pups undergoing rehabilitation. | rehabilitating pinniped pups are often admitted to care centers as neonates and generally lack maternal investment and are in poor body condition. upon admittance to a rehabilitation facility, pups are typically fed a milk replacement formula via gavage, which is switched to frozen fish upon weaning. while rehabilitation has been successful in terms of recovery and release, preweaning growth rates in captivity are consistently lower than in the wild. indicators of stress (cortisol and total thyr ... | 2013 | 22833416 |
| hiatal hernia in a harbor seal (phoca vitulina) pup. | a 2-wk-old stranded harbor seal (phoca vitulina) rescued by mystic aquarium showed signs of the presence of a hiatal hernia during rehabilitation. contrast radiographs of esophagus and stomach revealed an intrathoracic radiodensity that contains filling defects typical of stomach, consistent with gastric rugal folds. mural thickening was observed at the level of the cardia consistent with a diagnosis of a hiatal hernia. although clinical improvement was noted with medical therapy and tube feedin ... | 2012 | 22779241 |