Underwater Thrills:Swimming With Sharks: Da Shark - Elasmobranch .

Da Shark has dug up some fine reading by some well known names in the research community on artisanal elasmobranch fishing pressure in Baja.This is just flat out good stuff.As we have been blogging about for the preceding two days at least one species, the Great White, is under threat from regional long stock and gill net fishermen.

ack to the paper:AbstractArtisanalfisheries account for up to 80% of elasmobranch fishing activity inMexican waters, yet details associated with fishing effort and speciescomposition are generally unavailable. This paper describes a sight ofthe artisanal elasmobranch fishery of the Pacific coast of BajaCalifornia, Mexico from 2006 to 2008. The objectives were to determinethe geographic extent, size, and targets of the artisanal fishery, andto describe the catch characteristics at Laguna Manuela, an artisanalcamp where elasmobranchs are the main target. For the latter, we useda combination of beach surveys and a new survey method involving theidentification of discarded carcasses. Forty-four artisanal fishingcamps were identified, of which 29 (66%) targeted elasmobranchs at leastseasonally, using primarily bottom-set gillnets and longlines. AtLaguna Manuela 25 species of elasmobranchs were documented. Gillnettingaccounted for 60% of fishing effort, and the most commonly capturedspecies were Rhinobatos productus, Zapteryx exasperata, and Myliobatis californica. Longline fishing accounted for 31% of fishing effort, and the most commonly captured species were Prionace glauca and Isurus oxyrhinchus.Catch was composed of mainly juveniles for many species, indicatingthat the immediately surrounding area (Bahia Sebastian Vizcaino) may bean important elasmobranch nursery habitat. The results of this studywill serve as a baseline for determining future changes in the artisanalfishery, as good as changes in species demography and abundance. Daniel Cartamila,Omar Santana-Morales, Miguel Escobedo-Olvera, Dovi Kacev, LeonardoCastillo-Geniz, Jeffrey B. Graham, Robert D. Rubin and OscarSosa-Nishizaki