Fig. 1

Study area and divergent migration routes in narwhal. A Narwhal included in this study were a part of the Northern Baffin Bay population located in the Canadian Archipelago. B Narwhal seasonally migrate from summering areas, roughly encompassing fjords west of 75 ^oW longitude (vertical green line), with the main migratory corridor highlighted within the box area used to separate divergent migration strategies. C Distribution of individual narwhal locations derived using satellite telemetry during the autumnal migration period following departure from the summering grounds in northern Baffin Island (n = 41). Offshore individuals spent the majority of their time greater than 70 km from the coastline (roughly captured here by the 700 m isobath, broken blue contour) during the main migratory corridor (brown box), while nearshore individuals spent the majority of their time less than 70 km from the coastline. Other isobaths highlighted in increasingly thick grey contours from the coast, including 300 m, 1000 m, 1500 m, and 2000 m isobaths. (Narwhal silhouette from Phylopic via CC License Attribution-ShareAlike 3.0 Unported created by Chris huh)