Catches of target species and bycatches of an artisanal fishery: The case study of a trammel net fishery in the Portuguese coast

Abstract

In this work we studied an artisanal fishery targeting mainly soles ( Solea senegalensis and Solea solea) and cuttlefish ( Sepia officinalis) with trammel nets. Catches of target species, bycatches and discards were studied from October 2004 until August 2005 in the west coast of Portugal. A total of 37 sampling surveys onboard commercial fishing vessels were conducted. The number and weight of individuals of all species caught were registered, as well as the amount discarded and retained by fishermen. A total of 112 species were identified: Scomber japonicus, Chelidonichthys obscura and Callioynimus lyra were the most discarded fishes, corresponding to 28% in weight and 36% in number of discards. Discards represented 22%, in weight, of the total catches, while the amount retained by fishermen for consumption or direct selling was 12%, also in weight. The overall estimate of the annual discards value due to this fishery was ca. 170 tonnes, comprising near 45 fishing vessels. Inconsistencies between the catches recorded onboard and the official landings were detected for the main target species. Some bycatches of species under recovery plans were also found.