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Journal articles on the topic 'Harp seal'

Author: Grafiati

Published: 4 June 2021

Last updated: 31 July 2024

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1

Koster, Margie D., Keith Ronald, and Peter van Bree. "Thoracic anatomy of the Baikal seal, compared with some other phocid seals." Canadian Journal of Zoology 68, no. 1 (1990): 168–82. http://dx.doi.org/10.1139/z90-024.

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While undertaking the descriptive dissection of a Baikal seal (Phoca sibirica), the anatomy of the neck, thorax, and pectoral limbs were compared with that of a ringed seal, two harp seals, and two grey seals. Comparison of the myology showed the Baikal and the ringed seal to be the most similar, whereas the harp seals had more muscular subdivisions than the previous two species. The nonlobate lungs of the harp seal indicate a more advanced development. The grey seals were generally more robust with more pronounced areas of muscle attachment. Skeletal characteristics of the pectoral limb indic

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2

Kavtsevich, N. N., I. A. Erokhina, V. N. Svetochev, O. N. Svetocheva, and T. V. Minzyuk. "ECOLOGICAL AND ENVIRONMENTAL-PHYSIOLOGICAL RESEARCHES OF PINNIPEDS OF BARENTS, WHITE AND KARA SEAS IN 2015–2019." Transaction of the Kola Science Centre 11, no. 4 (2020): 198–214. http://dx.doi.org/10.37614/2307-5252.2020.11.4.009.

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A brief review of the most significant ecological and environmental-physiological studies of three species of true seals living in the arctic seas is presented. The results were obtained on the basis of the analysis of materials from the expeditions of Marine Mammals Laboratory in the Barents, White and Kara seas in 2015–2019. Special attention is paid to the application of satellite telemetry as well as hematological,biochemical, cytochemical methods in the study of harp seal, ringed seal, bearded seal.

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3

Aznar, F. Javier, Juan A. Balbuena, Mercedes Fernández, and J. Antonio Raga. "Establishing the relative importance of sympatric definitive hosts in the transmission of the sealworm, Pseudoterranova decipiens: a host-community approach." NAMMCO Scientific Publications 3 (November 24, 2001): 161. http://dx.doi.org/10.7557/3.2965.

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The importance of a given host to a particular parasite can be determined according to three different criteria: host preference, host physiological suitability and host contribution to transmission. Most studies on the sealworm Pseudoterranova decipiens have focussed on the latter factor, but few attempts have been made to develop a quantitative transmission model evaluating the relative importance of each host. The purpose of this study was to propose a flow-chart model to study sealworm transmission within a seal community. The model was applied to hypothetical data of four seal species act

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4

Debier, C., K. M. Kovacs, C. Lydersen, E. Mignolet, and Y. Larondelle. "Vitamin E and vitamin A contents, fatty acid profiles, and gross composition of harp and hooded seal milk through lactation." Canadian Journal of Zoology 77, no. 6 (1999): 952–58. http://dx.doi.org/10.1139/z99-059.

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This study reports fatty acid profiles and vitamin A and vitamin E contents of the milk of the harp seal (Phoca groenlandica) and hooded seal (Cystophora cristata) throughout the lactation period, as well as standard compositional analyses. The milk for this study was collected from harp and hooded seals breeding on the pack ice in the Gulf of St. Lawrence. Mother-pup pairs were serially captured, or point-sampled, in order to obtain milk samples during different lactation stages. Milk lipids showed the respective species' typical patterns during lactation, with a significant increase for harp

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5

Svetochev, Vladislav Nikolaevich, Nikolay Nikolaevich Kavtsevich, and Olga Nagimovna Svetocheva. "Satellite tagging and seasonal distribution of harp seal (juveniles) of the w hite sea-Barents sea stock." Czech Polar Reports 6, no. 1 (2016): 31–42. http://dx.doi.org/10.5817/cpr2016-1-4.

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Harp seal pups (4 ind.) were caught and marked with satellite telemetry transmitters (STT) in the White Sea in March-April 2010, the average tenure of STT was 226 ± 51.7 (103.6) days. In April the seals on the growth stage of "beater" left the White Sea on the drifting ice. In the Barents Sea the seals migrated north through the eastern part of the Barents Sea. Seals came to the northernmost point of their migration route, i.e. edge of the pack ice in the August – October period. One seal came out to the Greenland Sea. Seals’ return migration was in winter along the Novaya Zemlya to the south-

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6

Potelev, Vladimir, Kjell Tormod Nilssen, Vladislav Svetochev, and Tore Haug. "Feeding habits of harp (Phoca groenlandica) and hooded seals (Cystophora cristata) during late winter, spring and early summer in the Greenland Sea." NAMMCO Scientific Publications 2 (May 25, 2000): 40. http://dx.doi.org/10.7557/3.2970.

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Diet data were collected in the Greenland Sea pack ice (the West Ice) from March to June from harp seals (Phoca groenlandica) in 1987, 1990-1992 and 1997, and from hooded seals (Cystophora cristata) in 1992 and 1994, during Soviet Russian commercial sealing and on Norwegian scientific expeditions. The majority of both harp and hooded seal stomachs were empty but intestinal contents were found in most of the seals. The harp seal diet was totally dominated by the amphipods Parathemisto sp. and Gammarus sp., but krlll (Thysanoessa sp.) and polar cod (Boreogadus saida) were also eaten quite freque

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7

Cabanac, Arnaud, Lars P. Folkow, and Arnoldus Schytte Blix. "Volume capacity and contraction control of the seal spleen." Journal of Applied Physiology 82, no. 6 (1997): 1989–94. http://dx.doi.org/10.1152/jappl.1997.82.6.1989.

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Cabanac, Arnaud, Lars P. Folkow, and Arnoldus Schytte Blix.Volume capacity and contraction control of the seal spleen. J. Appl. Physiol. 82(6): 1989–1994, 1997.—Volume changes in the spleens of hooded seals ( Cystophora cristata) and harp seals ( Phoca groenlandica) were measured plethysmographically in vitro in response to epinephrine, norepinephrine, isoprenaline, phentolamine, and acetylcholine. Dilated spleens contracted forcefully within 1–3 min of α-adrenoceptor activation with 1.0–5.0 μg epinephrine/kg body mass, whereas stimulation of β-adrenoceptors and cholinergic receptors had littl

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8

Chapman, Robin S. "The Harp Seal." Hudson Review 50, no. 1 (1997): 100. http://dx.doi.org/10.2307/3852397.

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9

Svetocheva, Olga N., and Vladislav N. Svetochev. "Analysis of seasonality in trophic relationships of true seals (Phocideae) in the White Sea." Czech Polar Reports 5, no. 2 (2015): 230–40. http://dx.doi.org/10.5817/cpr2015-2-20.

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The analysis of interspecific trophic relations of true seals in the White Sea on the basis of long-term study, done on feeding, is shown. Main finding is that the ringed and bearded seals have no competitive interrelations. Contrastingly, the harp seal had an impact on background seals, intensity of the competition was, however, insignificant due of harp seal seasonal stay in the White Sea. The ice-free seals, i.e. grey and harbor seals, did not show a trophic competition with ice-liking seals thanks to seasonality of stay in the White Sea and insignificant number. The trophic competition of

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10

Kovacs, Kit M., Christian Lydersen, Mike O. Hammill, Bradley N. White, Paul J. Wilson, and Sobia Malik. "A HARP SEAL × HOODED SEAL HYBRID." Marine Mammal Science 13, no. 3 (1997): 460–68. http://dx.doi.org/10.1111/j.1748-7692.1997.tb00652.x.

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11

Christiansen, Jørgen S., Asbjørn Gildberg, Kjell T. Nilssen, Charlotta Lindblom, and Tore Haug. "The gastric properties of free-ranging harp (Pagophilus groenlandicus (Erxleben, 1777)) and hooded (Cystophora cristata (Erxleben, 1777)) seals." ICES Journal of Marine Science 61, no. 2 (2004): 287–92. http://dx.doi.org/10.1016/j.icesjms.2004.01.002.

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Abstract The study of trophic relationships in seals is based primarily on prey remains recovered from the digestive tract or scats. Basic data on the gastric properties of seals are scarce and are considered to be important to interpret data from dietary studies of these animals. Hence, we examined the key properties of the gastric chyme post mortem (i.e. temperature, acidity, and the concentration of the proteolytic enzyme pepsin) in free-ranging harp (Pagophilus groenlandicus, n=40) and hooded (Cystophora cristata, n=41) seals. Seals displayed huge inter-individual variations in their gastr

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12

Measures, L. N., J. F. Gosselin, and E. Bergeron. "Heartworm, Acanthocheilonema spirocauda (Leidy, 1858), infections in Canadian phocid seals." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 4 (1997): 842–46. http://dx.doi.org/10.1139/f96-342.

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Heartworm, Acanthocheilonema spirocauda, was observed in four of six species of seals (19 seals of 701) examined from the Atlantic coast of Canada including the Canadian Arctic. Fourteen of 221 ringed seals (Phoca hispida), 2 of 18 harbour seals (Phoca vitulina), 2 of 186 harp seals (Phoca groenlandica) (new host record), and the only hooded seal examined (Cystophora cristata) were infected with A. spirocauda. Intensity of infection ranged from 1 to 31. Infected seals were age 0 to 14, but 8 of the 14 infected ringed seals were age 0. All worms were found in the right ventricle except in three

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13

Lydersen, Christian, Lars Anker Angantyr, Øystein Wiig, and Torger Øritsland. "Feeding Habits of Northeast Atlantic Harp Seals (Phoca groenlandica) along the Summer Ice Edge of the Barents Sea." Canadian Journal of Fisheries and Aquatic Sciences 48, no. 11 (1991): 2180–83. http://dx.doi.org/10.1139/f91-257.

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Stomachs from 58 harp seals (Phoca groenlandica) from the northern part of the Barents Sea were collected between August 20 and September 5, 1987. Fifty-six of the stomachs contained identifiable remains. The amphipod Parathemisto libellula was the most common food item, found in 98% of the seal stomachs and constituting 57.9% of the total volume. Fish were the second most important prey group, with Arctic cod (Boreogadus saida) as the dominant species followed by Nybelin's sculpin (Triglops nybelini) and Greenland halibut (Reinhardtius hippoglossoides). Decapods, mainly Pandalus borealis, wer

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14

Moors, Hilary B., and John M. Terhune. "Calling depth and time and frequency attributes of harp (Pagophilus groenlandicus) and Weddell (Leptonychotes weddellii) seal underwater vocalizations." Canadian Journal of Zoology 83, no. 11 (2005): 1438–52. http://dx.doi.org/10.1139/z05-135.

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Harp seal (Pagophilus groenlandicus (Erxleben, 1777)) daytime calling depth during the breeding season and Weddell seal (Leptonychotes weddellii (Lesson, 1826)) daytime and nighttime calling depth during the winter and breeding seasons were investigated using a small vertical array with hydrophones placed at depths of 10 and 60 m. Rough calling depth estimates (<35 m, ~35 m, >35 m) and more accurate point depth estimates (±5–10 m in most cases) were obtained. Significantly more calls were produced at depths ≤35 m for both species. The point depth estimates indicated that the calls occurr

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15

Øigård, Tor Arne, and Hans J. Skaug. "Fitting state–space models to seal populations with scarce data." ICES Journal of Marine Science 72, no. 5 (2014): 1462–69. http://dx.doi.org/10.1093/icesjms/fsu195.

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Abstract We estimate temporal variation in fecundity, the reproduction rate, for Barents Sea and Greenland Sea harp seals using a state–space approach. A stochastic process model for fecundity is integrated with an age-structured population dynamics model and fit to available data for these two harp seal populations. Owing to scarceness of data, it is necessary to “borrow strength” from the Northwest Atlantic harp seal population in form of prior distributions on autocorrelation and variance in fecundity. Comparison is made to a simpler deterministic population dynamics model. The state–space

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16

Kunisch, EH, M. Graeve, R. Gradinger, et al. "Ice-algal carbon supports harp and ringed seal diets in the European Arctic: evidence from fatty acid and stable isotope markers." Marine Ecology Progress Series 675 (September 30, 2021): 181–97. http://dx.doi.org/10.3354/meps13834.

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Sea-ice declines in the European Arctic have led to substantial changes in marine food webs. To better understand the biological implications of these changes, we quantified the contributions of ice-associated and pelagic carbon sources to the diets of Arctic harp and ringed seals using compound-specific stable isotope ratios of fatty acids in specific primary producer biomarkers derived from sea-ice algae and phytoplankton. Comparison of fatty acid patterns between these 2 seal species indicated clear dietary separation, while the compound-specific stable isotope ratios of the same fatty acid

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17

Terhune, J. M., and K. Ronald. "Distant and near-range functions of harp seal underwater calls." Canadian Journal of Zoology 64, no. 5 (1986): 1065–70. http://dx.doi.org/10.1139/z86-159.

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Underwater vocalizations of harp seal (Phoca groenlandica) in the Gulf of St. Lawrence, were obtained during 10 breeding seasons between 1968 and 1983. No changes in their vocal repertoire were found. At high calling rates, vocalizations overlapped and the average sound levels increased. An individual's calls may be partly masked under these conditions. Sound levels of 140 dB re 1 μPa were received with no seal closer than 2 m from the hydrophone. Such sounds should be detectable (by other seals) from a distance of at least 2 km (uner ice cover). Recordings at points progressively farther away

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18

Nilssen, Kjell T., Ole-Petter Pedersen, Lars P. Folkow, and Tore Haug. "Food consumption estimates of Barents Sea harp seals." NAMMCO Scientific Publications 2 (May 25, 2004): 9. http://dx.doi.org/10.7557/3.2968.

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The consumption of various prey species, required by the Barents Sea harp seal (Phoca groenlandica) stock in order to cover their energy demands, has been estimated by combining data on the energy density of prey species and on seasonal variations in the energy expenditure and body condition of the seals. Data on diet composition and body condition were collected in the period 1990-1996 by sampling harp seals during different seasons, in various areas of the Barents Sea. All diet composition data were based on reconstructed prey biomass, and adjustments were made for differences in digestibili

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19

Haug, Tore, Kjell T. Nilssen, and Lotta Lindblom. "First independent feeding of harp seal (Phoca groenlandica) and hooded seal (Cystophora cristata) pups in the Greenland Sea." NAMMCO Scientific Publications 2 (May 25, 2000): 29. http://dx.doi.org/10.7557/3.2969.

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Data were collected from harp seal (Phoca groenlandica) and hooded seal (Cystophora cristata) pups belonging to the Greenland Sea (or "West Ice") stocks in 1995-1997. Pups of both species were observed to feed independently shortly after weaning, and their first food was almost exclusively crustaceans. Parathemisto sp., particularly P. libellula, dominated the diet of both the harp and the hooded seal pups, but the diet also contained sympagic amphipods of the genus Gammarus. Krill (Thysanoessa sp.) was of minor importance as food for seal pups in 1995, but occurred more frequentlyin the diet

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20

Gales, Rosemary, Deane Renouf, and Elizabeth Noseworthy. "Body composition of harp seals." Canadian Journal of Zoology 72, no. 3 (1994): 545–51. http://dx.doi.org/10.1139/z94-073.

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Using chemical analysis we measured the composition of 26 harp seals (Phoca groenlandica) representing both sexes, aged between 3 months and 30 years, and encompassing a wide range of body conditions. Predictive relationships between total body water and total body fat contents, total body protein content, and gross energy were calculated. These equations allow accurate estimation of harp seal body composition provided total body water content and body mass are known. Using these data we compared the accuracy of three existing equations that have been used to predict body fat content of other

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21

Gosselin, Jean-François, Lena N. Measures, and Jean Huot. "Lungworm (Nematoda: Metastrongyloidea) infections in Canadian phocids." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 4 (1998): 825–34. http://dx.doi.org/10.1139/f97-306.

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Otostrongylus circumlitus (Railliet, 1899) was found in 5% (16/308) of grey seals (Halichoerus grypus), 6% (1/17; intensity = 38) of harbour seals (Phoca vitulina), and none of 100 harp seals (Phoca groenlandica) from eastern Canada and none of 31 ringed seals (Phoca hispida) from Holman, Northwest Territories. Eighty-two percent of these infections were observed in young-of-the-year seals. Filaroides (Parafilaroides) gymnurus (Railliet, 1899), detected in nodules in the superficial parenchyma of the lungs, infected 24% (5/16) of grey seals, 27% (4/15) of harbour seals, 57% (29/51) of harp sea

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22

Cooke, Justin G. "Estimation of Harp Seal (Phoca groenlandica) Pup Production from Age Samples." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 3 (1985): 468–73. http://dx.doi.org/10.1139/f85-063.

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A simple numerical example shows that previously used procedures such as the "survival index" method for estimating the pup production in populations of harp seals (Phoca groenlandica) from samples of aged adults are unreliable because of their poor mathematical formulation. A corrected formulation, based on a maximum likelihood criterion, performed well in simulations tests. This was applied to age data from the Northwest Atlantic harp seal stock to obtain revised pup production estimates. A method to correct for the effects of errors in ageing also performed favourably in simulation trials.

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Trawicki, Marek B. "Multispecies discrimination of seals (pinnipeds) using hidden Markov models (HMMs)." Journal of the Acoustical Society of America 153, no. 3_supplement (2023): A222. http://dx.doi.org/10.1121/10.0018725.

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Hidden Markov models (HMMs) were developed and implemented for the discrimination of five available Seals (Pinnipeds), namely, the Bearded Seal (Erignathus Barbatus), Harp Seal (Pagophilus Groenlandicus), Leopard Seal (Hydrurga Leptonyx), Ross Seal (Ommatophoca Rossii), and Weddell Seal (Leptonychotes Weddellii). The main objectives of the experiments were to study the impact of the frame size and step size and number of states for feature extraction and acoustic models on classification accuracy. Based on the experimentation using Mel-Frequency Cepstral Coefficients (MFCCs) extracted from the

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Trawicki, Marek B. "Multispecies Discrimination of Seals (Pinnipeds) using Hidden Markov Models (HMMs)." International Journal of Automation, Artificial Intelligence and Machine Learning 4, no. 1 (2024): 1–9. http://dx.doi.org/10.61797/ijaaiml.v4i1.308.

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Hidden Markov Models (HMMs) were developed and implemented for the discrimination of 5 available Seals (Pinnipeds), namely the Bearded Seal (Erignathus barbatus), Harp Seal (Pagophilus groenlandicus), Leopard Seal (Hydrurga leptonyx), Ross Seal (Ommatophoca rossii), and Weddell Seal (Leptonychotes weddellii). The main objectives of the experiments were to study the impact of the frame size and step size and number of states for feature extraction and acoustic models on classification accuracy. Based on the experiments using Mel-Frequency Cepstral Coefficients (MFCCs) extracted from the vocaliz

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25

Stewart, R. E. A., and B. E. Stewart. "Mandibular dental anomalies of Northwest Atlantic harp seals, Phoca groenlandica." Canadian Journal of Zoology 65, no. 3 (1987): 769–71. http://dx.doi.org/10.1139/z87-121.

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We examined 2267 harp seal mandibles to determine the frequency of extra, missing, and malformed teeth; to examine the effect of these anomalies on longevity; and to assess the usefulness of anomalies in identifying stocks of seals. Supernumerary teeth occurred in 1.7% of the seals, 0.5% of the seals were missing teeth (none because of trauma), and 0.6% had morphologically deviant teeth. Only 0.2% of the seals had more than one type of anomaly and none had all three. Average age and age–frequency distributions for anomalous and normal seals were not different. Anomalies were probably too rare

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26

Duplisea, Daniel E. "Running the gauntlet: the predation environment of small fish in the northern Gulf of St Lawrence, Canada." ICES Journal of Marine Science 62, no. 3 (2005): 412–16. http://dx.doi.org/10.1016/j.icesjms.2004.11.005.

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Abstract Predation size spectra were constructed for the northern Gulf of St Lawrence, covering prey size ranges that include pre-recruit cod. Predation by fish and harp seals was modelled with a log-normally distributed predator–prey size ratio along with a relationship between predator body size and the energy required. Fish concentrate predation on prey of weight 0.5–2 g, whereas harp seals prefer prey of 60–125 g. It is speculated that predation caused by harp seals on pre-recruits could be a major factor limiting cod recruitment in the system. The northern Gulf of St Lawrence is a cold bo

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27

Ryg, Morten, Christian Lydersen, Nina H. Markussen, Thomas G. Smith, and Nils Are Øritsland. "Estimating the Blubber Content of Phocid Seals." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 6 (1990): 1223–27. http://dx.doi.org/10.1139/f90-142.

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We have investigated the relationships between percent blubber content and xiphostemal blubber thickness or girth-to-length ratios in ringed seal (Phoca hispida), harp seal (Phoca groeniandica), and grey seal (Halichoerus grypus). The blubber content was significantly correlated with blubber depths and girth-to-length ratios in all three species, in addition, we have developed an estimator for percent blubber content (the LMD-index) based on standard length (L, in meters), body mass (M, in kilograms), and on blubber thickness (d, in meters) measured at a defined position dorsally. From these v

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Øigård, Tor Arne, Tore Haug, and Kjell Tormod Nilssen. "From pup production to quotas: current status of harp seals in the Greenland Sea." ICES Journal of Marine Science 71, no. 3 (2013): 537–45. http://dx.doi.org/10.1093/icesjms/fst155.

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Abstract Harp seals (Pagophilus groenlandicus) have been harvested for centuries in the North Atlantic. Estimating abundance and monitoring changes in population size are critical for the management of the species. In March 2012, the harp seal pup production was estimated from aerial photographic surveys over the whelping areas. A total area of 305 km2 was photographed and 6034 pups were counted on the photos. From this the total pup production estimate was 89 590 ( s.e. = 12 310, CV = 13.7%). The status of the stock was subsequently assessed by fitting a population model to the independent pu

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29

Miller, Edward H., Ian L. Jones, and Garry B. Stenson. "Baculum and testes of the hooded seal (Cystophora cristata): growth and size-scaling and their relationships to sexual selection." Canadian Journal of Zoology 77, no. 3 (1999): 470–79. http://dx.doi.org/10.1139/z98-233.

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Growth and size-scaling of the baculum and testes in the moderately polygynous hooded seal (Cystophora cristata) were studied using 107 specimens of known age (1 month to 28 years) from the northwestern Atlantic. Bacular growth was rapid between 2 and 5 years of age: length increased 150% and "density" (i.e., mass/length) increased 8-fold and mass 20-fold. Growth continued throughout life. In large, old (>14 years) males, the baculum averaged 20.7 cm in length, 2.1 g/cm in density, and 44.4 g in mass. Bacular length increased relative to body length until seals were about 5 years of age, af

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30

Smith, Thomas G., and Ian Stirling. "Predation of Harp Seals, Pagophilus groenlandicus, by Polar Bears, Ursus maritimus, in Svalbard." ARCTIC 72, no. 2 (2019): 197–202. http://dx.doi.org/10.14430/arctic68186.

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Harp seals (Pagophilus groenlandicus) that breed in February and March in the White Sea migrate to open water around Svalbard and Franz Josef Land in the Barents Sea, feeding pelagically while following the receding ice edge northward to the edge of the polar pack. Although harp seals are present throughout the area during the summer, they are primarily pelagic and do not appear to be extensively preyed upon by polar bears (Ursus maritimus). However, occasionally, large numbers of harp seals may haul out and rest on the pack ice or feed in the water below the ice and surface to breathe between

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Haug, Tore, Garry B. Stenson, Peter J. Corkeron, and Kjell T. Nilssen. "Estimation of harp seal (Pagophilus groenlandicus) pup production in the North Atlantic completed: results from surveys in the Greenland Sea in 2002." ICES Journal of Marine Science 63, no. 1 (2006): 95–104. http://dx.doi.org/10.1016/j.icesjms.2005.07.005.

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Abstract From 14 March to 6 April 2002 aerial surveys were carried out in the Greenland Sea pack ice (referred to as the “West Ice”), to assess the pup production of the Greenland Sea population of harp seals, Pagophilus groenlandicus. One fixed-wing twin-engined aircraft was used for reconnaissance flights and photographic strip transect surveys of the whelping patches once they had been located and identified. A helicopter assisted in the reconnaissance flights, and was used subsequently to fly visual strip transect surveys over the whelping patches. The helicopter was also used to collect d

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Leaper, Russell, David M. Lavigne, Peter Corkeron, and David W. Johnston. "Towards a precautionary approach to managing Canada's commercial harp seal hunt." ICES Journal of Marine Science 67, no. 2 (2009): 316–20. http://dx.doi.org/10.1093/icesjms/fsp232.

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Abstract Leaper, R., Lavigne, D. M., Corkeron, P., and Johnston, D. W. 2010. Towards a precautionary approach to managing Canada's commercial harp seal hunt. – ICES Journal of Marine Science, 67: 316–320. The Canadian government's approach to the management of its commercial harp seal hunt is compared with other precautionary approaches developed for setting anthropogenic removal limits for marine mammal populations. For Canada's harp seal hunt, the current management strategy has not been fully specified or tested, and its robustness to changes in biological parameters, uncertainty in input d

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33

Terhune, Jack. "Introduction to the Harp Seal Data Set." Canadian Journal of Statistics / La Revue Canadienne de Statistique 28, no. 1 (2000): 183. http://dx.doi.org/10.2307/3315891.

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Nordøy, Erling Sverre. "Gastroliths in the harp seal Phoca Groenlandica." Polar Research 14, no. 3 (1995): 335–38. http://dx.doi.org/10.3402/polar.v14i3.6673.

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Terhune, J. M., G. MacGowan, L. Underhill, and K. Ronald. "Repetitive rates of harp seal underwater vocalizations." Canadian Journal of Zoology 65, no. 8 (1987): 2119–20. http://dx.doi.org/10.1139/z87-326.

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Underwater recordings of harp seal (Phoca groenlandica) vocalizations, obtained within the breeding herd during March, were examined with respect to calling rate and repetition of calls. Vocalizations typically overlapped one another. Calling rates ranged from 32 to 88 calls/min. Repetition rates averaged between 1.9 and 4.7 sound pulses/call (maximum repetition 24 times). Approximately 30% of the calls were not repeated and 40% were repeated twice. We found no significant relationships between calling rates and repetition rates. There were no variations in these factors throughout the day or

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NORDØY, ERLING SVERRE. "Gastroliths in the harp seal Phoca Groenlandica." Polar Research 14, no. 3 (1995): 335–38. http://dx.doi.org/10.1111/j.1751-8369.1995.tb00720.x.

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Terhune, J. M. "Geographical variation of harp seal underwater vocalizations." Canadian Journal of Zoology 72, no. 5 (1994): 892–97. http://dx.doi.org/10.1139/z94-121.

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Underwater vocalizations of harp seals (Phoca groenlandica) were recorded during the breeding season in the Gulf of St. Lawrence and north of Jan Mayen Island. Each herd had one unique call type and shared (often in different proportions) an additional 17 call types. Of these 17, 13 common call types had sample sizes large enough to permit statistical analysis of five duration, repetition, and pitch features. Only one of these call types exhibited no interherd differences; the others exhibited 1 – 5 different features. The average and maximum numbers of elements per call were higher in the Gul

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Ball, Mark D., Christopher P. Nizzi, Harold C. Furr, James A. Olson, and Olav T. Oftedal. "Fatty-acyl esters of retinol (vitamin A) in the liver of the harp seal (Phoca groenlandica), hooded seal (Cystophora cristata), and California sea lion (Zalophus californianus)." Biochemistry and Cell Biology 70, no. 9 (1992): 809–13. http://dx.doi.org/10.1139/o92-123.

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The fatty-acid composition of retinyl esters in the livers of two species of phocid seal, the harp seal (Phoca groenlandica, n = 20) and the hooded seal (Cystophora cristata, n = 15), and one species of otariid seal, the California sea lion (Zalophus californianus, n = 6), was determined. Vitamin A ranged in concentration from 4 to 1024 nmol retinol/g liver for the phocids and from 381 to 979 nmol/g liver for the otariids. In most of the livers, retinyl palmitate was not the principal ester, and the palmitate + stearate + oleate trio of retinyl esters represented less than 50% of the total. In

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Worthy, Graham A. J. "Metabolism and growth of young harp and grey seals." Canadian Journal of Zoology 65, no. 6 (1987): 1377–82. http://dx.doi.org/10.1139/z87-217.

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Metabolic rates and growth rates of juvenile harp and grey seals were monitored during the postweaning period after the onset of feeding. Growth rates varied from 0.03 to 0.32 kg d−1, depending on the level of energy intake and absolute body mass of the seal. Measurements of sculp mass (blubber with attached skin), as a percentage of total mass, indicated low rates of growth in the sculp and preferential growth in the core. When feeding started there was a 1.3- to 2.3-fold increase in standard metabolic rate, which was independent of the heat increment of feeding. Metabolic requirements of fee

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Hammill, Michael O., and Garry B. Stenson. "Comment on “Towards a precautionary approach to managing Canada's commercial harp seal hunt” by Leaper et al." ICES Journal of Marine Science 67, no. 2 (2010): 321–22. http://dx.doi.org/10.1093/icesjms/fsp296.

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Abstract Hammill, M. O., and Stenson, G. B. 2010. Comment on “Towards a precautionary approach to managing Canada's commercial harp seal hunt” by Leaper et al. – ICES Journal of Marine Science, 67: 321–322. The Objective-Based Fisheries Management used by Canada to manage the Northwest Atlantic seal hunt conforms to United Nations and Canadian Government precautionary approach frameworks in its structure and industry involvement. Managers and industry use clearly identified thresholds and harvest control rules to adjust quotas to respect the management framework. Although simulation testing is

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Ouellette, J., and K. Ronald. "Histology of reproduction in harp and grey seals during pregnancy, postparturition, and estrus." Canadian Journal of Zoology 63, no. 8 (1985): 1778–96. http://dx.doi.org/10.1139/z85-267.

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Reproductive tracts were collected on the eastern coast of Canada from adult female grey seals (Halichoerus grypus) during gestation and postparturition, and from adult female harp seals (Phoca groenlandica) during delayed implantation and postparturition. Reproductive tracts were fixed in 10% buffered formalin for light microscopy. The placental site and adjacent tissue were preserved in 2% glutaraldehyde – 1% paraformaldehyde for scanning electron microscopy. During the delay of blastocyst implantation, the endometria of the gravid and nongravid uterine horns were similar in microscopic appe

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Salberg, Arnt-Børre, Tor Arne Øigård, Garry B. Stenson, Tore Haug, and Kjell T. Nilssen. "Estimation of seal pup production from aerial surveys using generalized additive models." Canadian Journal of Fisheries and Aquatic Sciences 66, no. 5 (2009): 847–58. http://dx.doi.org/10.1139/f09-040.

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In this paper, we estimate the pup production of harp seals ( Pagophilus groenlandicus ) using generalized additive models (GAMs) based on thin-plate regression splines. The spatial distribution of seal pups in a patch is modelled using GAMs, and the pup production is estimated by numerically integrating the model over a fine grid area of the patch. Closed form expression for estimation of the the standard error of the pup production estimate is derived. The estimators are applied to simulated seal populations to investigate their properties. The results show that the proposed pup production e

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Shahidi, Fereidoon, Xin Chong, and Edward Dunajski. "Freshness Quality of Harp Seal (Phoca groenlandica) Meat." Journal of Agricultural and Food Chemistry 42, no. 4 (1994): 868–72. http://dx.doi.org/10.1021/jf00040a005.

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Nordøy, Erling S., Asbjørn Aakvaag, and Terje S. Larsen. "Metabolic Adaptations to Fasting in Harp Seal Pups." Physiological Zoology 66, no. 6 (1993): 926–45. http://dx.doi.org/10.1086/physzool.66.6.30163747.

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Van Opzeeland, Ilse C., and Sofie M. Van Parijs. "Individuality in harp seal, Phoca groenlandica, pup vocalizations." Animal Behaviour 68, no. 5 (2004): 1115–23. http://dx.doi.org/10.1016/j.anbehav.2004.07.005.

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Ryeng, KA, and SE Larsen. "The relative effectiveness of two expanding bullet designs in young harp seals (Pagophilus groenlandicus): A randomised controlled field study in the Norwegian harp seal hunt." Animal Welfare 30, no. 2 (2021): 155–67. http://dx.doi.org/10.7120/09627286.30.2.155.

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The aim of this study was to investigate the relative effectiveness of a rapidly expanding Bonded hunting bullet and an explosively expanding Varmint bullet in young harp seals (P). The study was conducted as an open, controlled and randomised parallel-group designed field trial. The animals were pre-randomised (1:1) into one explosively expanding (Varmint) and one expanding (Bonded) bullet type group, with 75 animals in each. The study sample consisted of young, weaned harp seals, 2–7 weeks of age, of both sexes, from the Greenland Sea harp seal population. The study was conducted during the

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Lipscomb, T. P., M. G. Mense, P. L. Habecker, J. K. Taubenberger, and R. Schoelkopf. "Morbilliviral Dermatitis in Seals." Veterinary Pathology 38, no. 6 (2001): 724–26. http://dx.doi.org/10.1354/vp.38-6-724.

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A juvenile female hooded seal ( Cystophora cristata) and a juvenile male harp seal ( Phoca groenlandica) stranded separately on the New Jersey (USA) coast and were taken to a marine mammal rehabilitation center. Both were lethargic and emaciated, had dermatitis, and died. Histologic skin lesions in the seals were similar and consisted of epidermal and follicular epithelial hyperplasia, hyperkeratosis, degeneration, and necrosis. The most distinctive finding was extensive syncytial zones bounded superficially by hyperkeratosis and deeply by hyperplastic basal cells. Eosinophilic intracytoplasmi

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Shibata, Takanori, and Kazuo Tanie. "Emergence of Affective Behaviors through Physical Interaction between Human and Mental Commit Robot." Journal of Robotics and Mechatronics 13, no. 5 (2001): 505–16. http://dx.doi.org/10.20965/jrm.2001.p0505.

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Recent advances in robotics have been applied to automation in industrial manufacturing, with the primary purpose of optimizing practical systems in terms of such objective measures as accuracy, speed, and cost. This paper introduces research on mental commit robot that seeks a different direction that is not so rigidly dependent on such objective measures. The main goal of this research is to explore a new area in robotics, with an emphasis on human-robot interaction. We introduced a cat robot a nd evaluated it by interviewing many people. The results showed that physical interaction improved

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Reeves, Randall R., George W. Wenzel, and Michael CS Kingsley. "Catch history of ringed seals (Phoca hispida) in Canada." NAMMCO Scientific Publications 1 (June 5, 1998): 100. http://dx.doi.org/10.7557/3.2983.

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The ringed seal (Phoca hispida) has always been a staple in the diet and household economy of Inuit in Canada. The present paper was prepared at the request of the NAMMCO Scientific Committee to support their assessment of ringed seal stocks in the North Atlantic Basin and adjacent arctic and subarctic waters. Specifically, our objective was to evaluate recent and current levels of use of ringed seals by Canadian Inuit. Annual removals probably were highest (possibly greater than 100,000) in the 1960s and 1970s, a period when sealskin prices were particularly strong. Catches declined substanti

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Renouf, D., Rosemary Gales, and Elizabeth Noseworthy. "Seasonal variation in energy intake and condition of harp seals: Is there a harp seal morph? Problems for bioenergetic modelling." Journal of Zoology 230, no. 3 (1993): 513–28. http://dx.doi.org/10.1111/j.1469-7998.1993.tb02703.x.

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