Spatiotemporal Variability of Target-Species in Tuna and Tuna-Like Fishing in Brazil

Abstract

Knowing the history of fishing-target catches and identifying them is essential for fish species conservation, mainly for the conservation of migratory species, whose stock assessment data are often provided by commercial fleets. Data on the catch, effort, and geographic distribution of fishing operations found in Banco Nacional de Dados da Pesca de Atuns e Afins-BNDA (National Database of Tuna and Tuna-like Species Fishing) were herein analyzed. The ratios between catches of different Tuna and tuna-like species were calculated and the identified patterns were used to classify what would be the target-species of the Brazilian fleet in different periods between 1978 and 2018. Based on the current results, there are three different exploration phases marking the Brazilian longline fleet. The first phase (1978-1981) was featured by the prevalence of Japanese vessels, which recorded the highest presence of swordfish on catching quantity within that period (with mean target-species indicator of. a k a k D 0 19 =. Além disso, a CPUE calculada reflete as variações do direcionamento da frota ao longo dos anos, bem como da biomassa das espécies analisadas. Palavras-chave: esforço de pesca; taxa de captura; alvo de pesca.