Trophic interactions and behavior of Bryde’s whales and other cetaceans in the Gulf of Mexico

The Gulf of Mexico Bryde’s whale (Balaenoptera edeni) population suffered injury due to the Deepwater Horizon.  This is an extremely small, isolated population with an estimated abundance of 33 individuals, a restricted habitat range, and very low levels of genetic diversity.

Its population size is comparable to that of the North Pacific right whale (31 individuals), one of the most critically endangered large whale species in the world.

Gulf of Mexico

The Gulf of Mexico Bryde’s whale population is listed as Endangered under the Endangered Species Act.

We study the foraging ecology and habitat use of endangered Bryde’s whales in the northeastern Gulf of Mexico

The scale of the DWH injury and the small population size makes Bryde’s whales a priority species for recovery management and restoration activities to promote recovery. A lack of information on Bryde’s whale trophic ecology and essential habitat requirements limits the ability to plan restoration activities and adequately plan for the long-term protection and recovery of this population.  Therefore, the primary objective of this research project is to develop a comprehensive ecological understanding of protected Gulf of Mexico Bryde’s whales, including the physical, oceanographic, and biological features defining critical habitats and their ecological role in Gulf of Mexico marine food webs. To address this objective, we conduct ship-based surveys to assess the habitat, spatial distribution, and foraging ecology of Gulf of Mexico Bryde’s whales using a multi-faceted approach that integrates visual and acoustic monitoring, environmental sampling, trawling, biopsy sampling for genetic and stable isotope analyses, and deployment of animal-borne tags sampling.

Models are developed to identify key trophic linkages and predator-prey interactions, improve characterization of Bryde’s whale habitat and exposure to anthropogenic mortality, and provide information to managers that will inform restoration and population recovery activities. This comprehensive study will significantly improve our understanding of the trophic ecology, habitat requirements and risks to the only resident baleen whale in the Gulf of Mexico.