Prey field and diet of larval cod on Western Bank, Scotian Shelf
In vertically integrated samples (from ≤ 75 m) taken around and over Western Bank in November and December 1991, and January 1992, densities of larval cod (Gadus morhua) correlated with those of copepods, notably with relative densities of copepodids plus adults of predominant prey, Pseudocalanus sp...
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1995
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crcansciencepubl:10.1139/f95-046a 2023-12-17T10:30:24+01:00 Prey field and diet of larval cod on Western Bank, Scotian Shelf McLaren, Ian A. Avendaño, Patricia 1995 http://dx.doi.org/10.1139/f95-046a http://www.nrcresearchpress.com/doi/pdf/10.1139/f95-046a en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 52, issue 3, page 448-463 ISSN 0706-652X 1205-7533 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 1995 crcansciencepubl https://doi.org/10.1139/f95-046a 2023-11-19T13:39:24Z In vertically integrated samples (from ≤ 75 m) taken around and over Western Bank in November and December 1991, and January 1992, densities of larval cod (Gadus morhua) correlated with those of copepods, notably with relative densities of copepodids plus adults of predominant prey, Pseudocalanus spp. and Paracalanus parvus. Pseudocalanus showed a large increase from time of cod spawning but was concentrated over the bank through gyral circulation rather than enhanced productivity. Numbers of both copepods in stomachs of larvae < 10 mm were significantly related to their field densities, when controlled for sample month, larva size, and time of day. Stomach fullness was related to sample month, time of day, size of larva, and density of Pseudocalanus, but not P. parvus. Smaller larvae from four depths at four stations over the bank in late 1992, ate mostly nauplii of Pseudocalanus and Centropages typicus. Numbers eaten were strongly related to their field densities, weakly to sample depth, and not to larva size. Stomach fullness was positively related only to densities of Pseudocalanus nauplii. Larvae > 5–6 mm switched to larger prey, mostly Pseudocalanus copepodids. More research is needed on interactions between copepod behaviour and the physical mechanisms that concentrate or disperse them on offshore banks. Article in Journal/Newspaper Gadus morhua Copepods Canadian Science Publishing (via Crossref) Canadian Journal of Fisheries and Aquatic Sciences 52 3 448 463 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics McLaren, Ian A. Avendaño, Patricia Prey field and diet of larval cod on Western Bank, Scotian Shelf |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
In vertically integrated samples (from ≤ 75 m) taken around and over Western Bank in November and December 1991, and January 1992, densities of larval cod (Gadus morhua) correlated with those of copepods, notably with relative densities of copepodids plus adults of predominant prey, Pseudocalanus spp. and Paracalanus parvus. Pseudocalanus showed a large increase from time of cod spawning but was concentrated over the bank through gyral circulation rather than enhanced productivity. Numbers of both copepods in stomachs of larvae < 10 mm were significantly related to their field densities, when controlled for sample month, larva size, and time of day. Stomach fullness was related to sample month, time of day, size of larva, and density of Pseudocalanus, but not P. parvus. Smaller larvae from four depths at four stations over the bank in late 1992, ate mostly nauplii of Pseudocalanus and Centropages typicus. Numbers eaten were strongly related to their field densities, weakly to sample depth, and not to larva size. Stomach fullness was positively related only to densities of Pseudocalanus nauplii. Larvae > 5–6 mm switched to larger prey, mostly Pseudocalanus copepodids. More research is needed on interactions between copepod behaviour and the physical mechanisms that concentrate or disperse them on offshore banks. |
format |
Article in Journal/Newspaper |
author |
McLaren, Ian A. Avendaño, Patricia |
author_facet |
McLaren, Ian A. Avendaño, Patricia |
author_sort |
McLaren, Ian A. |
title |
Prey field and diet of larval cod on Western Bank, Scotian Shelf |
title_short |
Prey field and diet of larval cod on Western Bank, Scotian Shelf |
title_full |
Prey field and diet of larval cod on Western Bank, Scotian Shelf |
title_fullStr |
Prey field and diet of larval cod on Western Bank, Scotian Shelf |
title_full_unstemmed |
Prey field and diet of larval cod on Western Bank, Scotian Shelf |
title_sort |
prey field and diet of larval cod on western bank, scotian shelf |
publisher |
Canadian Science Publishing |
publishDate |
1995 |
url |
http://dx.doi.org/10.1139/f95-046a http://www.nrcresearchpress.com/doi/pdf/10.1139/f95-046a |
genre |
Gadus morhua Copepods |
genre_facet |
Gadus morhua Copepods |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 52, issue 3, page 448-463 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f95-046a |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
52 |
container_issue |
3 |
container_start_page |
448 |
op_container_end_page |
463 |
_version_ |
1785583362529820672 |