Dataset Information

Long-term changes in habitat and trophic level of Southern Ocean squid in relation to environmental conditions.

ABSTRACT: Long-term studies of pelagic nekton in the Southern Ocean and their responses to ongoing environmental change are rare. Using stable isotope ratios measured in squid beaks recovered from diet samples of wandering albatrosses Diomedea exulans, we assessed decadal variation (from 1976 to 2016) in the habitat (?¹³C) and trophic level (?¹⁵N) of five important Southern Ocean squid species in relation to indices of environmental conditions-Southern Oscillation Index (SOI) and Southern Annular Mode (SAM). Based on ?¹³C values, corrected for the Suess effect, habitat had changed over the last 50 years for Taonius sp. B (Voss), Gonatus antarcticus, Galiteuthis glacialis and Histioteuthis atlantica but not Moroteuthopsis longimana. By comparison, mean ?¹⁵N values were similar across decades for all five species, suggesting minimal changes in trophic levels. Both SAM and SOI have increased in strength and frequency over the study period but, of the five species, only in Taonius sp. B (Voss) did these indices correlate with, ?¹³C and ?¹⁵N values, indicating direct relationships between environmental conditions, habitat and trophic level. The five cephalopod species therefore changed their habitats with changing environmental conditions over the last 50 years but maintained similar trophic levels. Hence, cephalopods are likely to remain important prey for top predators in Southern Ocean food webs, despite ongoing climate change.

SUBMITTER: Abreu J

PROVIDER: S-EPMC7494860 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Long-term changes in habitat and trophic level of Southern Ocean squid in relation to environmental conditions.

Abreu José J Phillips Richard A RA Ceia Filipe R FR Ireland Louise L Paiva Vítor H VH Xavier José C JC

Scientific reports 20200916 1

Long-term studies of pelagic nekton in the Southern Ocean and their responses to ongoing environmental change are rare. Using stable isotope ratios measured in squid beaks recovered from diet samples of wandering albatrosses Diomedea exulans, we assessed decadal variation (from 1976 to 2016) in the habitat (δ<sup>13</sup>C) and trophic level (δ<sup>15</sup>N) of five important Southern Ocean squid species in relation to indices of environmental conditions-Southern Oscillation Index (SOI) and Sou ...[more]

PMID: 32939006

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Dataset Information

Long-term changes in habitat and trophic level of Southern Ocean squid in relation to environmental conditions.

Publications

Long-term changes in habitat and trophic level of Southern Ocean squid in relation to environmental conditions.

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