Natural history, fisheries, and conservation of the Pacific guitarfish: signs of trouble in Peruvian waters

Abstract

This review examines—with a focus on Peru—the distribution, life-history, ecology, fisheries, historic and contemporary cultural importance, commerce, and management of the Pacific guitarfish Pseudobatos planiceps. In the eastern Pacific, Peru represents its most important habitats. The only 2 identified Important Shark and Ray Areas for this species are in Peru for feeding purposes. Other critical habitats are unidentified (e.g. reproductive). Most demographic parameters are unknown, since only length-at-maturity and fecundity have been determined. This species is a mesopredator that feeds on benthic invertebrates but also on Peruvian anchoveta. This trophic plasticity is unique among species within this genus. Globally, Peru has one of the longest species-specific landing datasets (56 yr) and one of the largest catches among countries that report guitarfish landings. This dataset shows a 98% decrease in landings from a peak in 1981 to a low in 2004, while fishing effort increased during this period, suggesting that depletion occurred in the early 1980s. The Pacific guitarfish is the third most landed ray species by artisanal fisheries in Peru, mainly between the central and northern regions. Adults are mainly caught using gillnets and as bycatch in trawling fisheries. Mid-northern Peru has a millennia-old tradition in Pacific guitarfish capture and consumption, and catch is not regulated. Along its distributional range, fisheries in Peru are the main cause of population decline; therefore, there is an urgency to halt this trend to protect the Pacific guitarfish. This review establishes a baseline, identifies information gaps, and provides recommendations to guide research and management for the species.