Impacts of Oceanic Conditions on North Atlantic Right Whale Distribution on the Nantucket Shoals

The habitat of North Atlantic right whales, like that of countless other species, is changing as a result of a changing climate. As scientists, proactive policy makers and innovative industries look for climate change solutions, the ocean is seen as providing myriad opportunities in the new blue economy. Offshore wind offers a promising alternative to fossil fuels, but impacts of turbine surveying, construction and operation on right whales are still largely unknown. Over the past decade, researchers at the Anderson Cabot Center for Ocean Life at the New England Aquarium have documented changes in right whale distribution in a historic whaling area overlapping with planned offshore wind development on the southern New England shelf. During a decade of aerial surveys, right whales began using the area year-round, with increasing abundance trends found in winters and springs. This study examined changes in oceanic conditions on the southern New England shelf and Nantucket Shoals with a potential relationship to the right whale abundance shifts between 2013 and 2019. Maps of coastal water masses and the fronts between them provided by satellite data are the basis for this comparative study. We identified water masses and their gradients during each season prior to 2016, and each season after 2016. The number of unique water masses and associated statistics were calculated for each season, which suggested a trend of convergence of seasonal averages of unique daily water masses in the survey area. We also compared which specific water masses were present prior to 2016 with those afterward, and analyzed the characteristics of those that exhibited substantial changes. Results suggest an overall cooling of water in the study area during winters and falls, and an overall warming during springs. Gradient values increased during spring, summer and fall months from the first time frame to the second. The percentage of area in which strong gradients were found increased meaningfully in summer and fall on the Nantucket Shoals. The goal of this study was to further understand the dynamic habitat of an imperiled species to contribute to the creation of tools for responsible wind energy development. While a transition away from fossil fuels will mitigate climate change impacts, strong preservation policies must be simultaneously enacted to protect right whales as new energy infrastructure is added to their environment.