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RESEARCH ARTICLE
Contents Vol 33(8)

Dietary analysis of regurgitates and stomach samples from free-living Australian sea lions

Rebecca R. McIntosh A , Brad Page B and Simon D. Goldsworthy B
+ Author Affiliations
- Author Affiliations

A Sea Mammal Ecology Group, Zoology Department, La Trobe University, Bundoora, Vic. 3086, Australia.

B SARDI Aquatic Sciences, 2 Hamra Avenue, West Beach, Adelaide, SA 5024, Australia.

Wildlife Research 33(8) 661-669 https://doi.org/10.1071/WR06025
Submitted: 5 March 2006  Accepted: 30 October 2006   Published: 19 December 2006

Abstract

Dietary remains recovered from Australian sea lion (Neophoca cinerea) digestive tracts and regurgitate samples from Seal Bay (Kangaroo Island, South Australia) were used to identify prey species consumed. Four of eight digestive tracts collected (50%) contained prey items located only in the stomach. On the basis of biomass reconstruction of cephalopod prey remains, octopus contributed 40% of the biomass in the samples, giant cuttlefish (Sepia apama) contributed 30% and ommastrephid squids contributed 14% biomass. The remains of several fish species were found in the samples: leatherjacket (Monocanthidae), flathead (Platycephalus sp.), swallowtail (Centroberyx lineatus), common bullseye (Pempheris multiradiata), southern school whiting (Sillago flindersi) and yellowtail mackerel (Trachurus novaezelandiae). Southern rock lobster (Jasus edwardsii) and swimming crab (Ovalipes australiensis) carapace fragments, little penguin (Eudyptula minor) feathers and bones and shark egg cases (oviparous species and Scyliorhinidae sp.) were also identified.


Acknowledgments

Thanks go to the staff of Seal Bay Conservation Park and the many volunteers for their assistance and support while in the field. P. D. Shaughnessy and S. Gibbs read various drafts for the manuscript and provided valuable comments. Thanks also to S. Gibbs for her assistance in the confirmation of identification of prey hard parts. This study was funded by Sea World Research and Rescue Foundation Inc., Kangaroo Island Sealink and La Trobe University. Research was conducted under permit U24630, provided by the Department for Environment and Heritage, South Australia and La Trobe University Animal Ethics Permit AEC00/42(L).


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