The status of cetaceans in Trinidad and Tobago

Marine ecosystems provide vital resources for humans and habitat for a vast number of other species. However, these ecosystems are being extensively degraded by human activities, and without effective management, will be unable to provide for humans or other species. In Trinidad and Tobago, as in other countries, one of the major obstacles to effective environmental management is a lack of appropriate information. This thesis aims to enhance the management of cetaceans in Trinidad and Tobago by providing much needed information on cetacean species within the country’s EEZ (Exclusive Economic Zone). Cetacean species diversity and distribution in Trinidad and Tobago is examined through the collation and verification of records from multiple data sources including systematic surveys, reports, skeletal remains, strandings and social media posts. This research provides the first comprehensive overview of the knowledge of cetacean species around Trinidad and Tobago through a verified cetacean species list, estimation of species diversity from local data and maps of species occurrence records. Species Distribution Models were developed for four species (Humpback Whales, Bottlenose Dolphins, Atlantic Spotted Dolphins and Rough-toothed Dolphins) which provide the first estimates of cetacean species distribution across the Trinidad and Tobago EEZ and identify possible cetacean species richness hotspots around the country. Fisher interviews were used to examine the threat posed by artisanal fisheries within the Trinidad and Tobago EEZ and provide the first comprehensive information on cetacean-fisheries interactions for the country. Hunting, depredation (a behaviour in which foraging cetaceans damage or remove catch or bait from fishing gear) and bycatch were all reported in the area. Bycatch was identified as the greatest threat posed by artisanal fisheries locally and analysis indicated that fishing with gillnets or fishing on the south coast of Trinidad with any gear increased the risk of bycatch. The findings of this study were used to recommend actions to improve cetacean management in Trinidad and Tobago, including the creation of a cetacean data management system, the development of a cetacean research programme to guide future research and mitigation of anthropogenic threats on the continental shelf, including cetacean bycatch in artisanal fisheries