Feeding habits of harp and hooded seals in drift ice waters along the east coast of Greenland in summer and winter

Haug, Tore; Nilssen, Kjell Tormod; Lindblom, Lotta

doi:10.3402/polar.v23i1.6264

Cited by 13 publications

(6 citation statements)

References 35 publications

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“…This is consistent with other studies that have found that food webs in Greenland waters are generally relatively simple with few species (Rigét et al, 2019). The pelagic amphipod P. libellula, polar cod, and capelin dominated the harp seal diet (63-99% of the observed diet, Haug et al, 2004;Enoksen et al, 2017). Greenland Sea and Barents Sea harp seals overlap in their feeding range during summer and autumn in Spitsbergen waters (Haug et al, 1994;Folkow et al, 2004), an area where crustaceans dominate their diet (Nilssen et al, 1995;Lindstrøm et al, 2013).…”

Section: Diet/feeding Ecologysupporting

confidence: 90%

Harp Seals: Monitors of Change in Differing Ecosystems

2020

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Section: Diet/feeding Ecologysupporting

confidence: 90%

Harp Seals: Monitors of Change in Differing Ecosystems

2020

Self Cite

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“…Among these carnivorous species, the pelagic amphipod Themisto libellula Lichtenstein in Mandt 1822 (Crustacea: Amphipoda: Hyperiidae) is highly abundant and widely distributed in the Arctic Ocean (Dunbar 1957 ; Dalpadado et al 2001 ; Dalpadado 2002 ). This amphipod could contribute significantly to energy transfers as it feeds mainly on copepods (Auel et al 2002 ; Dalpadado et al 2008 ; Marion et al 2008 ; Noyon et al 2009 ) and because it represents a major food source for higher predators such as fish (Hop et al 1997 ; Dalpadado and Bogstad 2004 ), seals (Nilssen et al 1995 ; Falk-Petersen et al 2004 ; Haug et al 2004 ) and seabirds (Lønne and Gabrielsen 1992 ).…”

Section: Introductionmentioning

confidence: 99%

Growth and lipid class composition of the Arctic pelagic amphipod Themisto libellula

et al. 2011

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Carnivorous zooplankton is a key element to the energy transfer through the arctic food web, linking lipid rich herbivores to the top predators. We investigated the growth and lipid dynamic of the Arctic pelagic amphipod Themisto libellula in Kongsfjorden (Svalbard, 79°N) from May to October 2007. Additional samplings were performed in spring and summer 2006 and further north in Rijpfjorden (80°N), in September 2006 and 2007. In Kongsfjorden, the first free-swimming stages (3 mm) appeared early May and reached their adult length (25 mm), in October. During their first year, they grew according to a Von Bertalanffy model and most probably constituted a single cohort. Juveniles had the highest growth rate (0.19 mm day−1) and revealed relatively low total lipid (TL) content (about 2.5% wet weight (WW)) with phospholipids as the major lipid class. Sub-adults showed a distinct decrease of growth rates which coincided with the increase of neutral lipid storage, reflecting a switch in energy allocation, from somatic growth to lipid storage. Indeed wax esters (WE) increased up to 48.5% TL on average in adults in 2006 while triacylglycerols (TAG) remained almost constant below 25.2% TL. The absence of lipid accumulation (in disproportion of the weight) in 2007 could be explained by a higher metabolism of T. libellula or preys of lower quality. In Rijpfjorden, adults in their second year continued accumulating lipid (up to 10% WW) with high and similar proportions of both lipid classes, WE and TAG. We highlighted that T. libellula exhibited a variable lipid metabolism along its life cycle depending on its physiological needs and environmental conditions.

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“…However, unlike the Barents Sea and Northwest Atlantic populations, Greenland Sea harp seals continue feeding on a pelagic invertebrate-dominated diet, mainly consisting of krill and amphipods (Themisto sp. ), during the breeding and moulting seasons in winter and spring in Arctic ice-filled areas in the Western Greenland Sea (Enoksen et al, 2017;Haug et al, 2002;Potelov et al, 2000). Overall, these results suggest that harp seals modify their diets to adapt to change in prey availability Øigård et al, 2013), switching between invertebrate-and fish-dominated diet.…”

Section: Multi-decadal Trends In Harp Seal Trophic Positionmentioning

confidence: 82%

Multi‐decadal trends in biomarkers in harp seal teeth from the North Atlantic reveal the influence of prey availability on seal trophic position

Vega

Kershaw

Stenson

et al. 2023

Global Change Biology

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Arctic food webs are being impacted by borealisation and environmental change. To quantify the impact of these multiple forcings, it is crucial to accurately determine the temporal change in key ecosystem metrics, such as trophic position of top predators. Here, we measured stable nitrogen isotopes (δ15N) in amino acids in harp seal teeth from across the North Atlantic spanning a period of 60 years to robustly assess multi‐decadal trends in harp seal trophic position, accounting for changes in δ15N at the base of the food web. We reveal long‐term variations in trophic position of harp seals which are likely to reflect fluctuations in prey availability, specifically fish‐ or invertebrate‐dominated diets. We show that the temporal trends in harp seal trophic position differ between the Northwest Atlantic, Greenland Sea and Barents Sea, suggesting divergent changes in each local ecosystem. Our results provide invaluable data for population dynamic and ecotoxicology studies.

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Feeding habits of harp and hooded seals in drift ice waters along the east coast of Greenland in summer and winter

Cited by 13 publications

References 35 publications

Harp Seals: Monitors of Change in Differing Ecosystems

Harp Seals: Monitors of Change in Differing Ecosystems

Growth and lipid class composition of the Arctic pelagic amphipod Themisto libellula

Multi‐decadal trends in biomarkers in harp seal teeth from the North Atlantic reveal the influence of prey availability on seal trophic position

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