Weekly predictions of North Atlantic right whale Eubalaena glacialis habitat reveal influence of prey abundance and seasonality of habitat preferences

摘要

Primary sources of mortality and serious injury to endangered North Atlantic right whales Eubalaena glacialis are vessel strikes and entanglement in fishing gear. All management plans depend on knowing when and where right whales are likely to be present. We tested the feasibility of a system designed to predict potential right whale habitat on a weekly time scale. The system paired right whale occurrence records with a collection of data layers including: results from a coupled biological?physical model of Calanus finmarchicus (the primary prey of right whales), satellite-derived sea surface temperature and chlorophyll, and bathymetry. Using these data, we trained seasonal habitat models and projected them onto environmental data for each 8 d period from January to June, 2002 to 2006. Two hypotheses were tested: (1) that right whale environmental preferences change from season to season and (2) that modeled prey concentration is an important predictor of the distribution of right whales. To test H_1, we trained, tested, and compared models for 3 time periods: winter, spring, and winter and spring combined. To test H_2, we trained and tested models with and without C. finmarchicus. Predictions of habitat suitability were highly dynamic within and across years. Our results support the hypothesis that right whale environmental preferences change between winter and spring. The inclusion of modeled C. finmarchicus abundance improved the accuracy of habitat suitability predictions.