Frontiers in Marine Science (Jun 2014)
Characterizing the fishing strategies and the temporal dynamics of the small-scale fleet operating in the Cíes Islands (NW Spain)
Abstract
Small-scale fisheries are characterized by a high diversification of fishing strategies and a highly dynamic pattern of their use in time and space that complicate data collection and management. Ignoring this variability can produce an incomplete image of the fisheries dynamics and thus can lead to the implementation of inappropriate regulations. In the present study we analyzed the fishing dynamics of the small-scale fleet operating around the Cíes Islands, situated in the marine National Park of Illas Atlánticas (Galicia, NW Spain). In spite of this protection figure created in 2002, no spatially-explicit information on the fishing system in the area is currently available and no specific management is applied. Fishery information systems in Galicia are related only to the landing ports, and the spatial aspects of the fishing operations are not available despite their importance for assessment and management. We carried out interviews with the fishers to first identify the fleet from nearby base ports operating in the Cíes Islands, and then to obtain temporal patterns of effort and catch data. A series of hierarchical cluster analyses of the individual monthly catch profiles was performed to identify the fishing strategies and to study their temporal dynamics. The Cíes fleet was composed of 565 boats coming from 11 ports of the South of Galicia. Although purse seine vessels were present in the park, the fishing effort was mainly exerted by the artisanal segment (vessels less than 12 m long using mobile and passive gears) because it was the largest sector in terms of number of boats. We identified 19 active and passive fishing gears operating in the Cíes Islands. Eight of them were selective gears (traps, clam rakes, and manual harvesting) which were specialized in capturing a single target species. In contrast, the remaining gears were multispecies (trammel nets, purse seine nets, gillnets, longlines, trawl) with a different catch species composition depending on the season, mesh size and the fishing zone. Thus, we identified up to 7 fishing strategies practiced with the same gear and aimed to catch different target species. In total 33 fishing strategies operating in Cíes Islands were described, being the most used ones: pots targeting common octopus and velvet crab; gillnet targeting hake and pouting; trammel net targeting either European spider crab or Ballan wrasse; clam rakes; and manual harvesting for goose-barnacles and razor shells. The main season in which each fishing strategy was used changed according to the fishing policy (e.g. closed seasons for target species or fishing gears), the fish prices, and the temporal variation in the abundance of target species.
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