Abstract
The environmental and biotic conditions affecting fisheries for cephalopods are only partially understood. A problem central to this is how climate change may influence population movements by altering the availability of thermal resources. In this study we investigate the links between climate and sea-temperature changes and squid arrival time off southwestern England over a 20-year period. We show that veined squid (Loligo forbesi) migrate eastward in the English Channel earlier when water in the preceding months is warmer, and that higher temperatures and early arrival correspond with warm (positive) phases of the North Atlantic oscillation (NAO). The timing of squid peak abundance advanced by 120-150 days in the warmest years ('early' years) compared with the coldest ('late' years). Furthermore, sea-bottom temperature was closely linked to the extent of squid movement. Temperature increases over the five months prior to and during the month of peak squid abundance did not differ between early and late years, indicating squid responded to temperature changes independently of time of year. We conclude that the temporal variation in peak abundance of squid seen off Plymouth represents temperature-dependent movement, which is in turn mediated by climatic changes associated with the NAO. Such climate-mediated movement may be a widespread characteristic of cephalopod populations worldwide, and may have implications for future fisheries management because global warming may alter both the timing and location of peak population abundance.
Full Text
The Full Text of this article is available as a PDF (123.5 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Both C., Visser M. E. Adjustment to climate change is constrained by arrival date in a long-distance migrant bird. Nature. 2001 May 17;411(6835):296–298. doi: 10.1038/35077063. [DOI] [PubMed] [Google Scholar]
- Crubézy E., Murail P., Girard L., Bernadou J. P. False teeth of the Roman world. Nature. 1998 Jan 1;391(6662):29–29. doi: 10.1038/34067. [DOI] [PubMed] [Google Scholar]
- Davis A. J., Jenkinson L. S., Lawton J. H., Shorrocks B., Wood S. Making mistakes when predicting shifts in species range in response to global warming. Nature. 1998 Feb 19;391(6669):783–786. doi: 10.1038/35842. [DOI] [PubMed] [Google Scholar]
- Hurrell J. W. Decadal trends in the north atlantic oscillation: regional temperatures and precipitation. Science. 1995 Aug 4;269(5224):676–679. doi: 10.1126/science.269.5224.676. [DOI] [PubMed] [Google Scholar]
- Post E., Forchhammer M. C., Stenseth N. C., Callaghan T. V. The timing of life-history events in a changing climate. Proc Biol Sci. 2001 Jan 7;268(1462):15–23. doi: 10.1098/rspb.2000.1324. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schneider S. H. What is 'dangerous' climate change? Nature. 2001 May 3;411(6833):17–19. doi: 10.1038/35075167. [DOI] [PubMed] [Google Scholar]