Cetacean occurrence, habitat preferences and potential for cetacean-fishery interactions in Iberian Atlantic waters: Results from cooperative research involving local stakeholders

17 páginas, 5 tablas, 3 figuras.-- Sabine Goetz ... et al.

1. Iberian Atlantic waters are heavily exploited by Spanish and Portuguese fi sheries. Overlaps between fi shery target species and cetacean diet, and between fi shing grounds and cetacean foraging areas, can lead to cetacean – fi shery interactions includin g bycatch mortality of cetaceans. 2. The present study assesses cetacean distribution, habitat preferences and hotspots for cetacean – fi shery interactions by using a cooperative research approach with stakeholder participation ( fi shers, fi sheries observers, fi sheries authorities, scientists), as well as the combination of different opportunistic data sources (interviews, on-board observations). The usefulness of each data type is evaluated. The implications of results for the monitoring and mitigation of cetacean – fi shery interactions are discussed. 3. Generalized linear models and GIS maps were used to relate cetacean occurrence patterns to environmental variables (geographic area, water depth, coastal morphology) and to fi shing activities ( fi shing grounds, fi sheries target species). 4. Common and bottlenose dolphins were the most frequently sighted species, the former in waters > 50 m, frequently from purse seiners and trawlers, and the latter particularly inside the south Galician rías and close to vessels operating further offshore in Portuguese waters. Harbour porpoises were seen over the whole continental shelf, often next to beach seines, while long- fi nned pilot whales and striped dolphins were mostly seen from vessels fi shing offshore. 5. Results suggest that cetacean occurrence is linked to prey distribution and that interactions with fi sheries are most likely for common dolphins (with coastal purse seines and offshore trawls), bottlenose dolphins and harbour porpoises (coastal nets). The different data sources were complementary and provided results broadly consistent

Interviews in Galicia were carried out in the framework of the project ECOSUMMER ( ECOsystem approach to Sustainable Managament of the Marine Environment and its living Resource )with EU funding (projects MEXC-CT-2006-042337 and MEST-CT-2005-020501). The interview survey in Portugal was conducted under the SafeSea Project ( Sustainable local fi sheries and promotion of a safe sea for cetaceans ) and supported by the EEA Grants programme (EEA Financial Mechanism 2004-2009). SG was also funded by the German Academic Exchange Service (DAAD) and the Fundação para a Ciência e a Tecnologia (FCT). MBS participation was part of the EU FP7 grant MYFISH (no. 289257) and the LOTOFPEL project (Plan Nacional de I + D + I, CTM 2010-16053). The Whalewatch Project was fi nanced by the Xunta de Galicia (programme PEME I+D e I+D SUMA)

Peer reviewed