Reanalyses of Gulf of Mexico fisheries data: Landings can be misleading in assessments of fisheries and fisheries ecosystems
- *Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA 70803-7503; and
- ‡School of Aquatic and Fisheries Sciences, University of Washington, Box 355020, Seattle, WA 98195
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Edited by John J. Magnuson, University of Wisconsin, Madison, WI, and accepted by the Editorial Board December 27, 2007 (received for review May 9, 2007)
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Fig. 1.Annual mean trophic level index from 1950 to 2006. USA only is the northern Gulf of Mexico and the Atlantic south of Chesapeake Bay. GOM is the Gulf of Mexico only. Overlap can be seen when comparing GOM with USA only, and when comparing all indices without shrimp and menhaden with Louisiana survey data. The solid line is the trend line from Pauly and Palomares (6).
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Fig. 2.The closed squares show the cumulative percentage of fisheries that collapsed in the Gulf of Mexico between 1950 and 2001 based upon the criterion used by Worm et al. (9), e.g., when an annual catch fell below 10% of the maximum observed catch in any year. The closed triangles show the same results after considering effects of the regulatory history of each fishery using existing management plans and stock assessments, and cases where changes in commercial fishing effort and market forces seemed to be driving observed variability.
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Fig. 3.Annual landings (×1,000 lbs) of red snapper attributable to different fisheries in the Gulf of Mexico. The figure is annotated to include the time sequences of major changes in harvest quotas, and changes in the projected time for recovery of the stock under various management practices. Bycatch landings occur in the shrimp fishery and comprise mostly age-0 and age-1 juveniles that have not yet recruited to the directed fishery. The annotations refer to: (line 1) development of the red snapper FMP (1984); (line 2) 3.1 million pounds (mp) commercial quota was set (1990); (line 3) 4 mp quota was set, allocation was set to 51% commercial and 49% recreational, and recovery was projected for 2007 (1991); (line 4) quota was raised to 6 mp, recovery was projected for 2009 (1993); (line 5) quota was raised to 9.12 mp, recovery was projected for 2019 (1996); (line 6) shrimp trawls in federal waters were required to contain bycatch reduction devices (1998); (line 7) recovery was projected for 2032 (2003); (line 8) quota was reduced to 5 mp.
Footnotes
- †To whom correspondence should be addressed. E-mail: jhcowan{at}lsu.edu
- © 2008 by The National Academy of Sciences of the USA
