Polar cod (Boreogadus saida) and capelin (Mallotus villosus) as key species in marine food webs of the Arctic and the Barents Sea

Abstract Oceanographic conditions in the Arctic are changing, with sea ice cover decreasing and sea temperatures increasing. Our understanding of the effects on marine populations in the area is, however, limited. Here, we focus on the Barents Sea stock of polar cod (Boreogadus saida). Polar cod is a key fish species for the transfer of energy from zooplankton to higher trophic levels in the Arctic food web. We analyse the relationships between 30-year data series on the length-at-age of polar cod cohorts (ages 0–4) and sea surface temperature, sea ice concentration, prey biomasses, predator indices, and length-at-age the previous year using multiple linear regression. Results for several ages showed that high length-at-age is significantly associated with low sea ice concentration and high length-at-age the previous year. Only length-at-age for age 1 shows a positive significant relationship with prey biomass. Our results suggest that retreating sea ice has positive effects on the growth of polar cod in the Barents Sea despite previous observations of a stagnating stock biomass and decreasing stock abundance. Our results contribute to identifying mechanisms by which climate variability affects the polar cod population, with implications for our understanding of how future climate change may affect Arctic ecosystems.

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Notes on the fishes of the Severnaya Zemlya archipelago and the spawning area of polar cod Boreogadus saida (Gadidae)

Proceedings of the Zoological Institute RAS ◽

10.31610/trudyzin/2021.325.2.248 ◽

2021 ◽

Vol 325 (2) ◽

pp. 248-268

Author(s):

N.V. Chernova ◽

V.A. Spiridonov ◽

V.L. Syomin ◽

M.V. Gavrilo

Keyword(s):

Arctic Charr ◽

Kara Sea ◽

The Arctic ◽

Polar Cod ◽

Boreogadus Saida ◽

Spawning Area ◽

Fish Samples ◽

Polar Cod Boreogadus Saida ◽

Severnaya Zemlya ◽

Severnaya Zemlya Archipelago

Data on the fishes of the high-latitude Severnaya Zemlya archipelago (the North Land) is presented. The archipelago is located in the Arctic on the border between the Kara Sea and the Laptev Sea. The ichthyofauna of the archipelago has not been studied; therefore, even small collections are of interest. Fish samples were obtained during the expedition “Open Ocean: Arctic Archipelagos – 2019: Severnaya Zemlya”. In addition, the samples from this area in the collections of the Zoological Institute (ZIN) were studied, which have been received from polar expeditions to the Kara and Laptev seas during the entire era of polar research. The most significant fact is the discovery of mass accumulation of polar cod Boreogadus saida (Lepechin, 1774) larvae in Mikoyan Bay (Bolshevik Island), which gives evidence of important spawning grounds near Severnaya Zemlya. Indirect evidence of this can be found in the publications of polar explorers who overwintered on Severnaya Zemlya in the 1930s–1950s and have reported that the polar cod approaches the shores for spawning in August, in huge schools. The waters of Severnaya Zemlya represent the spawning area of polar cod in the central part of the Eurasian shelf, which is not mentioned in current literature. In addition to polar cod, a few more species are registered in samples from the coastal waters of the archipelago (depths to 38 m), rough hookear sculpin Artediellus scaber Knipowitsch, 1907, twohorn sculpin Icelus bicornis (Reinhardt, 1840) (family Cottidae), Liparis tunicatus Reinhardt, 1836, black-bellied snailfish L. cf. fabricii (Liparidae), Knipowich eelpout Gymnelus knipowitschi Chernova, 1999 (Zoarcidae) and three-spined stickleback Gasterosteus aculeatus (Linnaeus, 1758) (Gasterosteidae). In the deepwater straits, snailfish Careproctus sp. (174–234 m) and pale eelpout Lycodes pallidus Collett, 1879 (105–348 m) were found. The Arctic charr Salvelinus alpinus (Linnaeus, 1758) (Salmonidae) inhabits some lakes of the archipelago. This is the first finding of a three-spined stickleback in the east of the Kara Sea.

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Isotopic niche overlap between co-occurring capelin (Mallotus villosus) and polar cod (Boreogadus saida) and the effect of lipid extraction on stable isotope ratios

Polar Biology ◽

10.1007/s00300-017-2199-8 ◽

2017 ◽

Vol 41 (3) ◽

pp. 423-432 ◽

Cited By ~ 1

Author(s):

D. G. McNicholl ◽

G. K. Davoren ◽

A. R. Majewski ◽

J. D. Reist

Keyword(s):

Stable Isotope ◽

Lipid Extraction ◽

Niche Overlap ◽

Stable Isotope Ratios ◽

Polar Cod ◽

Isotopic Niche ◽

Boreogadus Saida ◽

Mallotus Villosus ◽

Capelin Mallotus Villosus ◽

Polar Cod Boreogadus Saida

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Trophic interactions affecting a key ecosystem component: a multistage analysis of the recruitment of the Barents Sea capelin (Mallotus villosus)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-064 ◽

2010 ◽

Vol 67 (9) ◽

pp. 1363-1375 ◽

Cited By ~ 22

Author(s):

Dag Øystein Hjermann ◽

Bjarte Bogstad ◽

Gjert Endre Dingsør ◽

Harald Gjøsæter ◽

Geir Ottersen ◽

...

Keyword(s):

Trophic Interactions ◽

Gadus Morhua ◽

Barents Sea ◽

Clupea Harengus ◽

Mallotus Villosus ◽

The Barents Sea ◽

Key Species ◽

Capelin Mallotus Villosus ◽

Ecosystem Component ◽

Recruitment Stages

The Barents Sea stock of capelin ( Mallotus villosus ) has suffered three major collapses (>90% reduction) since 1985 due to recruitment failures. As capelin is a key species in the area, these population collapses have had major ecosystem consequences. By analysing data on spawner biomass and three recruitment stages (larvae, 0-group, and 1-year-olds), we suggest that much of the recruitment failures are caused by predation from herring ( Clupea harengus ) and 0-group and adult Northeast Arctic cod ( Gadus morhua ). Recruitment is furthermore positively correlated with sea temperatures in winter and spring. Harvesting of maturing capelin on their way to the spawning grounds reduced the abundance of larvae significantly, but this reduction to a large extent is compensated for later in life, as mortality is strongly density-dependent between the larval stage and age 1. Altogether, our study indicates a very high importance of trophic interactions, consistent with similar findings in other high-latitude marine ecosystems.

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Introduction: Marine Harvesting in the Arctic

ICES Journal of Marine Science ◽

10.1093/icesjms/fsu072 ◽

2014 ◽

Vol 71 (7) ◽

pp. 1932-1933 ◽

Cited By ~ 2

Author(s):

Tore Haug ◽

Michaela Aschan ◽

Alf Håkon Hoel ◽

Torild Johansen ◽

Jan H. Sundet

Keyword(s):

Barents Sea ◽

Marine Ecosystem ◽

Trophic Levels ◽

The Arctic ◽

Life History Strategies ◽

Polar Cod ◽

Polar Regions ◽

Ice Coverage ◽

Pagophilus Groenlandicus ◽

Polar Cod Boreogadus Saida

Abstract In a warmer Arctic, living conditions will change at all trophic levels of the marine ecosystem. Increased air and water temperatures will likely substantially reduce ice coverage. Trophic interactions might change and increased competition between resident Arctic species and invasive species seems likely. A theme session on “Marine harvesting in the Arctic” was held at the international Arctic Frontiers Conference in Tromsø, Norway, in January 2013. The theme session partitioned the topic into two sub-sessions: (i) introduced species, immigration and fate of resident species and (ii) prospective harvesting of marine biological resources in the Arctic. The four articles that follow this introduction are based on presentations made at the Arctic Frontiers theme session. These articles cover topics such as: how ice breeding seals (Pagophilus groenlandicus) can cope with ice retention in the Northwest Atlantic, how planktonic stages of the resident polar cod (Boreogadus saida) and the pole-ward expanding Pacific sand lance (Ammodytes hexapterus) may compete for food in the warming Beaufort Sea, and how the introduced red king crab (Paralithodes camtschaticus) disperse in the Barents Sea. The fourth article shows how differences in the life-history strategies of keystone zooplankton species will likely affect future productivity of commercial fisheries in polar regions.

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