Incidental Capture of Juvenile Fish from an Artisanal Fishery in a Coastal Lagoon in the Gulf of California

Abstract

Fishing gear used in artisanal penaeid shrimp fisheries in the southwestern Gulf of California usually consists of the trawl net, gill net, and suripera net. These net types are known to capture a high quantity of fish bycatch and are likely to cause high levels of juvenile fish mortality. However, juvenile bycatch mortality has not been documented in previous studies. The aim of this work was to study the effect of a local artisanal shrimp fishery on the juvenile fish community in the coastal lagoon of Santa Maria la Reforma, Sinaloa, Mexico. Length at first maturity was estimated for the seven most abundant species; based on this information, a generalized linear model and a Bayesian approach were used to estimate the probabilities of juvenile fish capture for different types of fishing gear. We found that the three net types captured juveniles, even those of species maturing at small lengths, and were likely to impact the recruitment of the analyzed species, as the probability of juvenile capture by the nets ranged from 0.20 to 0.90. However, the species for which sexual maturity was attained at a smaller length were less vulnerable to the fishing gear types analyzed. The gill net and trawl net had the highest probabilities of capturing juveniles in general, whereas the suripera net showed a high probability of capturing juveniles belonging to certain species. Incidentally, the suripera net is the gear used most frequently in the area to catch shrimp.