Analysis of the small-scale fleet’s coverage under different biological sampling strategies: from the DCR stock-based sampling to the concurrent DCF métier-based sampling in the Northern Spanish coastal gillnets fleet.

Abstract

One of the major contributions of the current EU Data Collection Framework (DCF) was the shift from a stock-based approach towards a fishery-based approach. The aim of this change was serving the new demands of the fisheries management in order to include the ecosystem approach in the assessments. Since 2009, the MS national fisheries sampling programs had to adopt the concurrent sampling strategy, which implies that length structure of all species landed must be obtained during the sampling operation.

The Northern Spanish coastal small scale fleet represents a major challenge for sampling due to the multi-species and multi-gear character and the complexity of the fleets’ dynamics. Particularly, the small-scale gillnets called “beta” represents one the more complex Spanish métiers in terms of catches (1850 t in 2014), effort (23341 trips), geographical distribution (Division VIIIc and IXa), and the number of exploited species (38 species within 90% of total landings). Some of the most important species are hake, horse mackerel, pouting, red mullet, pollack, gurnards, small-spotted catshark or sole.

The analytical approach adopted here is to compare, under statistical and logistical perspectives, the biological data compiled for the North-western Spanish small-scale gillnets before and after the concurrent sampling implementation. The potential improvement in stock assessment and fisheries management are also considered.