Contribution of the onboard observer program of the province of Chubut, Argentina, to the biodiversity knowledge throughout bycatch analysis.

GÓNGORA MARÍA EVA; BOVCON NELSON DARIO; COCHIA PABLO DANIEL; SOUTRIC MATÍAS; MENDIA LUIS; CAILLE GUILLERMO MARTÍN

Viña del Mar

Workshop; 7th International Fisheries Observer and Monitoring Conference IFOP; 2013

IFOP

Control of by-catch or incidental catch is a challenge to fisheries, particularly difficult to manage in shrimp fisheries. In Argentina, the Patagonian shrimp (Pleoticus muelleri) is one of main fishery products for export, with highly variable landings over the past 20 years, which reached two historic peaks of 80,000 tons in 2001 and 2011. The fishery, which provides 95% of reported landings of shrimp, operates in a breeding area of common hake (Merluccius hubbsi), reaching at an incidental capture of this species, mainly youth of around 35,000 tons per year. The control/reduction of by-catch of hake is the main challenge that the management of this fishery faces. However, a significant number of other species are also caught incidentally. This partial attention to by-catch of commercial species contrasts with the ecosystem approach to fisheries management, where sustainability of all species caught must be addressed. The present work describes the by-catch in the fishery of Patagonian shrimp that develops in San Jorge gulf and adjacent waters (between 43 ° and 47 ° South). The information is collected by the ?On-board Observers Program? of the Chubut province (POBCh), which is led by the Undersecretary of Fisheries of the province and has the support of the Faculty of Natural Sciences (FCN) of the Universidad Nacional de la Patagonia San Juan Bosco. Observers identified in each fishing haul, captured species at lowertaxonomic level possible. For each taxon, their abundance is reflected in numbers in five categories (dominant, abundant, common, rare and very rare) and its destination (fully encased, partially encased or completely thrown to the sea). The training for the identification of species required a major effort. This task was carried out by the FCN, and has been implemented for nearly ten years through a permanent training strategy. Since 2003 recognized species list reaches 117 species (2 hagfishes, 28 cartilaginous fishes, 59 bony fishes and 28 crustaceans); four of them categorized as "endangered" and four as "vulnerable" by the IUCN (2012). Evaluation of incidental capture has allowed to deepen the knowledge about the biodiversity of the region; expanding knowledge of the distribution of 22 species. In addition, the collected samples gave rise to a fish collection in the FCN, which today are part of the "national network of biological collections of Argentina".