One of the main threats to the Gulf of California's marine biodiversity comes from industrial and artisanal fishing. The use of shrimp dragnets in the Gulf, gillnets with inadequate mesh sizes, and long-lines in both the Gulf and the Pacific, are creating serious concerns for the long-term sustainability of the marine ecosystems around the Baja California peninsula.11
Industrial shrimp trawling exacts a harsh toll on the Gulf's marine environment. More than 1,100 shrimp trawlers in the Gulf of California annually rake an area of sea floor equivalent to four times the total size of the Gulf, damaging fragile benthic habitats and capturing nearly 10 kilos of bycatch species for every kilo of shrimp caught. Catch-per-unit effort is declining, while fuel and export subsidies artificially sustain the overcapacity of industrial fishing fleets. Large artisanal fleets operating in nearly open access conditions also contribute to overharvesting. A recent survey by Conservation International estimates that there are between 9,000 and 18,000 small boats active at any one time in the Gulf.12
In the Upper Gulf, illegal gillnet fishing targeting the totoaba, a large endemic and threatened fish, also incidentally captures an endangered endemic porpoise called the vaquita. The most recent survey estimates 567 vaquitas remain, and annual mortality rates (ranging between 39 and 84) are considered unsustainable. Poaching of sea turtles is also a problem throughout the Gulf of California and Baja California, although turtle-excluder devices are now mandatory for industrial fishing vessels. Recent research on the Gulf's shark and ray fishery indicates that depletion of the larger classes of sharks due to commercial artisanal fishing may have already taken place.13
Citations
11 Ezcurra, Exequiel. Conservation and Sustainable Use of Natural Resources in Baja California: An Overview. October 1998.
12 The David and Lucile Packard Foundation, Conservation Program. A Strategic Focus for the Mexico Program. June 30, 2000.
13 Ibid.
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