Estimating cetacean abundance and distribution around Vancouver Island, B.C., using data collected from an opportunistic platform

British Columbia (B.C.) is home to 25 species of cetaceans, six of which are listed as at risk of extinction by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and under the Species at Risk Act (SARA). It is crucial to learn more about the distribution, abundance, and habitat use of these species. However, because cetaceans can be wide-ranging and distributed sparsely over vast areas, statistically robust systematic studies can be expensive and logistically challenging. To overcome these issues, my research aims to use a platform of opportunistic sightings, Straitwatch, to generate estimates of abundance and spatial distribution for 6 species of cetaceans commonly found off Vancouver Island. During the summers of 2008 and 2009, Straitwatch collected effort and sightings data during non-systematic surveys of three regions. These data were analyzed using model-based distance sampling methods. Results of these analyses are useful for (1) determining cetacean habitat use, (2) identifying and protecting critical habitats or creating marine protected areas, and (3) for identifying areas where cetaceans are at greater risk to anthropogenic disturbance such as entanglement/bycatch in fishing gear.