Atlantic cod (Gadus morhua) feed during spawning off Newfoundland and Labrador

• Published in: ICES Journal of Marine Science
• Main Authors: Krumsick, Kyle J., Rose, George A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 2012
• Subjects: atlantic cod; Gadus morhua; Newfoundland; Northwest Atlantic
• Online Access: http://dx.doi.org/10.1093/icesjms/fss158; http://academic.oup.com/icesjms/article-pdf/69/10/1701/29149649/fss158.pdf

Abstract Krumsick, K. J., and Rose, G. A. 2012. Atlantic cod (Gadus morhua) feed during spawning off Newfoundland and Labrador. – ICES Journal of Marine Science, 69: 1701–1709. We test a current assumption that Atlantic cod (Gadus morhua) off Newfoundland and Labrador, Canada, do not feed during the protracted spawning season (March–September). Stomach contents were analysed from 10 473 cod from four Northwest Atlantic Fisheries Organization regions (2J, 3K, 3L, and 3Ps) over 9 years from which gonads were also analysed to determine sex and maturity status. Adult cod in spawning condition did feed in all regions, usually at rates equivalent to or even greater than non-spawning fish and juveniles. Both sexes fed during spawning, though females consumed lesser amounts. Regional differences were evident. The total fullness index was greater in the northern (2J) than the southern (3Ps) region, with no consistent differences between spawners and non-spawners. The most southerly region (3Ps) exhibited the greatest prey diversity, the northern region (2J) the least. Shrimp was the major diet item in the northern regions. Capelin, zooplankton, crab, and other fish increased in importance to the south. Differences in prey items between non-spawning and spawning individuals of both sexes were possibly related to spawning behaviour. Models using consumption rates should not assume that cod do not feed during the protracted spawning season in these waters.