The impact of rising sea temperatures on an Arctic top predator, the narwhal.

摘要: Arctic top predators are expected to be impacted by increasing temperatures associated with climate change, but the relationship between sea and population dynamics of cetaceans remains largely unexplored. Narwhals (Monodon monoceros) considered among most sensitive endemic marine mammals change due their limited prey selection, strict migratory patterns high site fidelity. In context we assume that narwhals partly influenced changes in environmental conditions, warm areas having lower abundance narwhals. Using a unique large dataset 144 satellite tracked narwhals, surface temperature (SST) data spanning 25 years (1993-2018) narwhal estimates from 17 localities, (1) assessed thermal exposure this species, (2) investigated SST trends at summer foraging grounds, (3) We showed sharp increase Northwest, Mideast Southeast Greenland, whereas no could detected Canadian Archipelago (CAA) Greenland Sea. The rising were correlated smallest observed ( 40,000 individuals). These results support hypothesis warming ocean waters will restrict habitat range narwhal, further suggesting may under pressure abandon traditional habitats warming, consequently either migrate North or locally go extinct.