Abstract
The Gulf of Maine (GoM) is currently one of the fastest warming bodies of water on the planet and has been since 2004. Marine mammals are able to adapt the timing of their habitat use in response to changes in their environments, such as warming waters and loss of prey sources. It is possible that whale distributions in the GoM have been altered over the past few decades due to warming waters. Naturalists and captains that have worked at Bar Harbor Whale Watch Company (BHWW) for 20+ years anecdotally described how whale watch trips must go much farther now than in the past in order to find whales. This project analyzed BHWW sightings data over the past 15 years to determine if long term changes occurred in the local distribution of baleen whale sightings. To carry out this study, ArcGIS was utilized to display and spatially analyze sightings data from BHWW between 2009 and 2023. R Studio was used to determine if the quantity of each species of baleen whale sighted changed significantly over time, and if the overall number of whales sighted changed significantly. Results indicated that concentrations of baleen whale sightings shifted from the Inner and Outer Schoodic Ridges to Grand Manan Banks over the 15-year period. Sightings counts of fin whales, humpback whales, and whale sightings counts have significantly decreased over the 15-year period. The change in sightings locations has resulted in BHWW cruises traveling an extra 40 km to find whales. Overall sightings counts have decreased by almost two thirds, making whales harder to find. Whales may be traveling further northeast, or far outside of BHWW search areas, to find food. Warming water temperatures are thought to be forcing prey to shift their distribution, in turn altering whale distribution. The 10 hottest years of annual average SST in the GoM occurred during this study, indicating there could be a strong link between changes in whale watch sightings and rising water temperatures. Alterations in whale and prey distributions in the GoM should be studied closely as temperatures will continue to rise in the future.