ICES Journal of Marine Science: Journal du Conseil Advance Access originally published online on June 7, 2007
ICES Journal of Marine Science: Journal du Conseil 2007 64(5):945-955; doi:10.1093/icesjms/fsm064
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The ecology of Sepia australis (Cephalopoda: Sepiidae) along the south coast of South Africa
ski1,
1 Department of Environmental Affairs and Tourism, Marine and Coastal Management, Private Bag X2, Rogge Bay, Cape Town 8012, South Africa
2 Department of Fisheries and Marine Biology, University of Bergen, Bergen N-5020, Norway
Correspondence to M. R. Lipi
ski: tel: +27 21 4023148; fax: +27 21 4023639; e-mail: lipinski{at}deat.gov.za
Mqoqi, M., LipiThe influence of abiotic factors (depth, region, temperature, salinity, and oxygen) on the abundance of the cuttlefish Sepia australis was investigated using data from bottom-trawl stations occupied in April/May (austral winter) 1988 and August/September (austral spring) 2001 off South Africa' south coast. April/May survey data for 1999, 2003, and 2004, and August/September data for 2003 and 2004 were used to assess regional or depth-related patterns in abundance. Temperature differences in the two years mainly analysed influenced distribution and abundance significantly. Abundance increased eastwards in 2001 presumably because of a high-temperature anomaly stretching westwards (i.e. limiting the species abundance to the west), whereas abundance increased westwards in the more typical winters of 1988, 1999, 2003, and 2004. Abundance increased with depth in spring 2001, 2003, and 2004. Smaller sizes of mature males may indicate that they mature earlier than females. The main prey of all size groups and maturity stages was crustaceans, and there were no size- or maturity-related changes in diet. It appears that S. australis is an opportunistic feeder dependent on whatever prey of appropriate size is abundant at any time. However, the data show an array of patterns, some likely to be the result of biological flexibility in response to a changing environment. Other patterns are part of more stable, well-balanced ecological characteristics of the species.ski, M. R., and Salvanes, A. G. V. 2007. The ecology of Sepia australis (Cephalopoda: Sepiidae) along the south coast of South Africa. ICES Journal of Marine Science, 64: 945955.
Keywords: cuttlefish, diet composition, distribution and abundance, ecology
Received 6 October 2006; accepted 25 March 2007; advance access publication 7 June 2007.