Characterizing the complexity of the fleet dynamics for an effective fisheries management: The case of the Cíes Islands (NW Spain)

Rosana Ouréns,Juan Freire,Giulia Cambiè

doi:10.3989/scimar.04228.08a

Rosana Ouréns, Juan Freire + Show 1 more

Open Access

https://doi.org/10.3989/scimar.04228.08a

Copy DOI

Abstract

We analysed the fishing fleet dynamics in the Cies Islands, located in a National Land-Marine Park of Galicia. By interviewing fishers we identified the fleet fishing in the study area and obtained temporal data on effort and catch. Then we performed multivariate analyses of the catch profiles to identify the fishing strategies and their temporal dynamics. Our results highlight the complexity of the fishery system, composed of 565 boats that used 19 fishing gears and 33 strategies in an area of 26.6 km 2 . Octopus and velvet crab pots, gillnets targeting hake, trammel nets targeting European spider crab or ballan wrasse, clam rakes, and hand harvesting of gooseneck barnacles and razor shells are the strategies most used. In addition, most of the boats are generalists and use up to seven different fishing strategies throughout the year. This flexibility of the fleet to change the target species generates a wide diversity of annual fishing patterns that increases the complexity of the fisheries and the difficulty of managing them. The implementation of data collection programmes that include fleet dynamics and spatial data are key factors for developing effective management regulations consistent with the complexity of the system.

Highlights

The fraction of assessed stocks fished within biologically sustainable levels decreased by almost 20%from 1974 to 2011 (FAO 2014), and the situation seems to be even worse for unassessed fisheries (Costello et al 2012)
Our results highlight the complexity of the fishery system, composed of 565 boats that used 19 fishing gears and 33 strategies in an area of 26.6 km2
Most of the boats are generalists and use up to seven different fishing strategies throughout the year. This flexibility of the fleet to change the target species generates a wide diversity of annual fishing patterns that increases the complexity of the fisheries and the difficulty of managing them

Summary

Introduction

The fraction of assessed stocks fished within biologically sustainable levels decreased by almost 20%from 1974 to 2011 (FAO 2014), and the situation seems to be even worse for unassessed fisheries (Costello et al 2012). Depending on the context in which they work, boats can change their target species in order to maximize the economic benefits and use different fishing strategies or mètiers (combinations of fishing area, target species, season and fishing gear; see Tzanatos et al 2006) Ignoring this variability can generate a simplistic and biased vision of the fishing activity, which may lead to misinterpretation of how fishers allocate the fishing effort in space and time and of the impact caused by the fishing effort on the ecosystem (Salas and Gaertner 2004, Forcada et al 2010, Maynou et al 2011, Martín et al 2014). Fishers’ behaviour is one of the main sources of uncertainty associated with the fishing systems, so ignoring the patterns of human interventions could undermine the effectiveness of management strategies (FAO 2003, Fulton et al 2011, Maravelias et al 2014)

Methods

Results

Discussion

Conclusion