Spatial-Temporal Analysis of North Atlantic Right Whale Aerial Surveillance in Relation to Whale Habitats and Active Fishing Areas in Atlantic Canada

Abstract

The North Atlantic right whale (NARW) is a critically endangered migratory species found primarily along the Eastern coasts of North America. Consistent surveillance for NARW is vital to informing management measures, triggering dynamic protections, and monitoring changing population trends and distribution. Surveillance of known and potential NARW habitats is also important to ensure that protection and knowledge are adequate throughout their range. Resources for aerial surveillance in Atlantic Canada are limited, leading to a focus on areas and times of known aggregations in the southern Gulf of St. Lawrence (GSL). Although this spatial-temporal bias in effort is widely recognized, its extent and consequences have not been quantified. This project examined the spatial-temporal coverage of Canada’s dedicated marine mammal surveillance program in Atlantic Canada from 2018-2021 and evaluated effort as distance surveyed (km) using GPS-recorded track line data obtained from Fisheries and Oceans Canada. We examined the amount of effort allocated across specific areas throughout Atlantic Canada relevant to NARW protection. These areas included general NARW habitats and snow crab and lobster fishing areas during their active seasons. Effort was concentrated in the southern GSL, while the migratory corridor along the Scotian Shelf and critical habitats in the Bay of Fundy and Roseway Basin lacked surveillance, along with several active fishing areas and potential future habitat. This evaluation of uneven surveillance effort provides important context for interpreting our perceived knowledge of NARW distribution in Canada and potentially encountered anthropogenic threats.