Stomach Contents of Breeding Common Murres Caught in Gillnets off Newfoundland

Abstract

Abstract We examined the stomach contents of 64 male and 43 female Common Murres (Uria aalge) caught in gillnets during late chick rearing/early chick departure period in August 2002 near breeding colonies in Witless Bay, Newfoundland, Canada. Twenty-six percent of stomachs contained no food. All others contained exclusively fish, and Capelin (Mallotus villosus) was the only fish positively identified. Gravid female Capelin were found in 82% of murre stomachs with contents. The number of fish ingested by murres differed between the sexes, with a mean of 2.7 fish in male stomachs and 1.6 fish in female stomachs. Mean mass of stomach contents did not differ between the sexes (males: 27.0 g; females: 22.6 g). Overall, results were similar to Common Murre diets recorded in the 1980s, despite changes in Capelin distribution and biology. The sample of Common Murres collected as gillnet bycatch was male-biased (59%). Males may have been more vulnerable to being caught in gillnets, perhaps because they were engag...