Climate-driven variation in the quantity, quality and availability of endangered baleen whale food

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Climate change is altering marine food web function leading to redistribution of lower trophic level biomass in all oceans. Redistribution can lead to local food reductions for mobile marine predators such as fish and mammals in traditional foraging habitats. Our knowledge of mobile marine predator sensitivity to the cumulative impacts of climate change, changing food supply and other risks is very limited. It is important to explain how mobile animals respond to shifts in food distribution, but there are logistical and technological limitations to measuring food characteristics in the ocean. The proposed research addresses these issues for endangered baleen whales that eat high concentrations of zooplankton. Although poor health or range shifts have been observed in baleen whales, a lack of concurrent information on food abundance, quality or availability across the large ranges these animals inhabit has usually precluded robust assessment of the effect of food variation on population dynamics, health and distribution relative to other explanations, including direct human impacts. My research program seeks to explain the role and significance of climate-driven variation in food quantity and quality on baleen whale ecology on the Northwest Atlantic continental shelf, focusing primarily on the endangered North Atlantic right whale and secondarily on rorqual whale species. My first objective is to characterize climate-driven environmental constraints on baleen whale food quantity and quality among oceanographically distinct habitats using field observations. Our lab is leading a team of international collaborators to conduct concurrent oceanographic and marine mammal surveys in different habitats; some of which are experiencing stronger climate change impacts than others.  My second objective is to develop an autonomous mobile acoustic predator-prey and climate measurement system to enhance our ability to measure baleen whale food quantity and distribution. To do this, my lab will equip undersea gliders with acoustic recorders that measure whale sounds and echosounders to measure whale food, as well as sensors measuring key climate variables. The echosounders are newly developed technology and we will test their performance.  We will use multi-sensor gliders to concurrently measure the distribution of baleen whales and their associated habitat conditions persistently over broad space and time scales.  This research will be carried out by students in the Davies Lab at the University of New Brunswick. This research program will advance prediction of climate change impacts on baleen whale populations, which is a critical element of predicting extinction risk and facilitating effective policy and management action to save these species. My lab will advance whale research globally with the novel application of recent technologies that address data deficiency challenges in other baleen whale species that few others are addressing.