Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis
Capelin ( Mallotus villosus ) is the key forage fish species in the Newfoundland and Labrador Shelf ecosystem. Capelin stocks collapsed in the early 1990s, concurrent with declines in “northern” Atlantic cod, Gadus morhua . Neither has fully recovered yet. Changes in growth, condition, and behaviour...
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fthighwire:oai:open-archive.highwire.org:icesjms:71/4/775 2023-05-15T15:27:39+02:00 Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis Obradovich, Shannon G. Carruthers, Erin H. Rose, George A. 2014-06-01 00:00:00.0 text/html http://icesjms.oxfordjournals.org/cgi/content/short/71/4/775 https://doi.org/10.1093/icesjms/fst184 en eng Oxford University Press http://icesjms.oxfordjournals.org/cgi/content/short/71/4/775 http://dx.doi.org/10.1093/icesjms/fst184 Copyright (C) 2014, International Council for the Exploration of the Sea/Conseil International pour l'Exploration de la Mer Original Articles TEXT 2014 fthighwire https://doi.org/10.1093/icesjms/fst184 2015-02-28T22:23:13Z Capelin ( Mallotus villosus ) is the key forage fish species in the Newfoundland and Labrador Shelf ecosystem. Capelin stocks collapsed in the early 1990s, concurrent with declines in “northern” Atlantic cod, Gadus morhua . Neither has fully recovered yet. Changes in growth, condition, and behaviour accompanied capelin declines on the northern Grand Banks (NGB), and remain two decades later. Feeding, growth, and condition of NGB capelin were all lower when compared with capelin from the eastern Scotian Shelf (ESS), where abundance increased following predator declines. For age 2–5 capelin of both sexes, all but one of five comparable age–sex groups were significantly larger on the ESS (e.g. age 3 females average 169 mm on the ESS and 151 mm on the NGB). Neither temperature nor density-dependence explain these differences. However, dietary differences were prominent. ESS capelin had higher total fullness indices ( TFI s) than NGB fish at all sizes [mean TFI ESS = 1.43 (± 1.14), mean TFI NGB = 0.48 (± 0.70)]. Euphausiids (especially Thysanoessa spp.) were a main dietary component on the ESS but not on the NGB. Stable isotope analyses (δ15N and δ13C) for NGB capelin also indicated few dietary euphausiids. Trophic fractionation of δ 15N was 4.740/ 00 , suggesting NGB capelin were food limited. Capelin recovery on the Newfoundland and Labrador Shelf appears limited by bottom-up forcing, in particular lack of euphausiid prey. Text atlantic cod Gadus morhua Newfoundland HighWire Press (Stanford University) Labrador Shelf ENVELOPE(-58.000,-58.000,56.000,56.000) Newfoundland ICES Journal of Marine Science 71 4 775 783 |
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English |
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Original Articles |
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Original Articles Obradovich, Shannon G. Carruthers, Erin H. Rose, George A. Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
topic_facet |
Original Articles |
description |
Capelin ( Mallotus villosus ) is the key forage fish species in the Newfoundland and Labrador Shelf ecosystem. Capelin stocks collapsed in the early 1990s, concurrent with declines in “northern” Atlantic cod, Gadus morhua . Neither has fully recovered yet. Changes in growth, condition, and behaviour accompanied capelin declines on the northern Grand Banks (NGB), and remain two decades later. Feeding, growth, and condition of NGB capelin were all lower when compared with capelin from the eastern Scotian Shelf (ESS), where abundance increased following predator declines. For age 2–5 capelin of both sexes, all but one of five comparable age–sex groups were significantly larger on the ESS (e.g. age 3 females average 169 mm on the ESS and 151 mm on the NGB). Neither temperature nor density-dependence explain these differences. However, dietary differences were prominent. ESS capelin had higher total fullness indices ( TFI s) than NGB fish at all sizes [mean TFI ESS = 1.43 (± 1.14), mean TFI NGB = 0.48 (± 0.70)]. Euphausiids (especially Thysanoessa spp.) were a main dietary component on the ESS but not on the NGB. Stable isotope analyses (δ15N and δ13C) for NGB capelin also indicated few dietary euphausiids. Trophic fractionation of δ 15N was 4.740/ 00 , suggesting NGB capelin were food limited. Capelin recovery on the Newfoundland and Labrador Shelf appears limited by bottom-up forcing, in particular lack of euphausiid prey. |
format |
Text |
author |
Obradovich, Shannon G. Carruthers, Erin H. Rose, George A. |
author_facet |
Obradovich, Shannon G. Carruthers, Erin H. Rose, George A. |
author_sort |
Obradovich, Shannon G. |
title |
Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
title_short |
Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
title_full |
Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
title_fullStr |
Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
title_full_unstemmed |
Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis |
title_sort |
bottom-up limits to newfoundland capelin (mallotus villosus) rebuilding: the euphausiid hypothesis |
publisher |
Oxford University Press |
publishDate |
2014 |
url |
http://icesjms.oxfordjournals.org/cgi/content/short/71/4/775 https://doi.org/10.1093/icesjms/fst184 |
long_lat |
ENVELOPE(-58.000,-58.000,56.000,56.000) |
geographic |
Labrador Shelf Newfoundland |
geographic_facet |
Labrador Shelf Newfoundland |
genre |
atlantic cod Gadus morhua Newfoundland |
genre_facet |
atlantic cod Gadus morhua Newfoundland |
op_relation |
http://icesjms.oxfordjournals.org/cgi/content/short/71/4/775 http://dx.doi.org/10.1093/icesjms/fst184 |
op_rights |
Copyright (C) 2014, International Council for the Exploration of the Sea/Conseil International pour l'Exploration de la Mer |
op_doi |
https://doi.org/10.1093/icesjms/fst184 |
container_title |
ICES Journal of Marine Science |
container_volume |
71 |
container_issue |
4 |
container_start_page |
775 |
op_container_end_page |
783 |
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1766358070315712512 |