Baleen Whale Occurrence in the Waters Off Virginia and North Carolina, U.S.A. From 2001 to 2019

Abstract

Eighteen years of visual survey and strandings data were used to describe baleen whale occurrence along the continental shelf of Virginia and North Carolina, U.S.A. This region experiences heavy anthropogenic use, which poses risks for mortality and injury to baleen whales. Between 2001 and 2019, six species of baleen whales were recorded, and whales occurred year-round. The total number of (on- and off-effort) sightings and strandings amounted to 838 whales, including humpback (Megaptera novaeangliae, n = 503), fin (Balaenoptera physalus, n = 197), North Atlantic right (Eubalaena glacialis, NARW, n = 76), common minke (B. acutorostrata, n = 51), sei (B. borealis, n = 10), and blue (B. musculus, n = 1) whales. Spatial modeling and abundance estimates indicated whale density and distribution changed seasonally. The highest densities of all whales combined occurred in winter and spring. Across seasons, average densities were highest in the northern portion of the study area. Ninety percent of NARW sightings were outside the designated Seasonal Management Areas in place for their protection. The stranding record offered a complementary view of species richness and seasonality. This study provides a baseline of baleen whale occurrence in an area experiencing increasing anthropogenic pressures (e.g., ship traffic and offshore wind-energy development).