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• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Key words; pilot whale; stable isotope; diet; mackerel; squid; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.624.1898; http://icesjms.oxfordjournals.org/content/54/3/500.full.pdf

Carbon ( C / C) and nitrogen ( N / N) stable isotope ratios were measured in skin rodents 1983). ted to 81) for taceans, 1988). et al. tudy of es such cted to a func-nsump-specific on andand muscle samples from free-ranging long-finned pilot whales stranded or caught in fishing gear in two locations in the western north Atlantic. Samples of the principal pilot whale prey species, long-finned squid and a secondarily important species, Atlantic mackerel, were collected for stable isotope analysis from three areas in the western north Atlantic. The stable carbon and nitrogen ratios from the mackerel and squid samples did not diVer between areas. However, carbon ratios diVered between the two prey species, while the nitrogen ratios did not. The diVerence between the stable nitrogen isotope ratios for prey and predator suggests trophic enrichment of 1.1 to 1.7‰, values substantially lower than previously assumed for cetaceans. The diVerences between carbon ratios among prey species and whale tissues suggest that mackerel comprise a significant proportion of the diet of pilot whales.