Abstract: The feeding ecology of juvenile and subadult Guadalupe fur seals (Arctocephalus townsendi) at San Benito Archipelago, Baja California, Mexico, was investigated to determine if dietary differences exist between these two age classes. During the summer of 2007, 108 scats of fur seals were collected from areas used mainly by juveniles (n = 54 scats) or subadults (n = 54 scats). Cephalopod beaks and/or otoliths were found in all samples collected. Only 702 squid beaks of 1,144 were identified to species level (61.3%). Only four of eight otoliths found were identified to species level (50%). Six squid species and two fish species were identified. Both juveniles and subadults showed similar dietary composition; however, differences between prey selection were found. The California market squid (Loligo opalescens) was the most common squid species for both age classes in the summer of 2007.

Key Words: Guadalupe fur seal, Arctocephalus townsendi, San Benito Archipelago, California market squid, Loligo opalescens, cephalopods, juveniles, subadults

Document Type: Research article

DOI: 10.1578/AM.39.2.2013.125

Page Numbers: 125-131

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