Winter occurrence of minke whales (Balaenoptera acutorostrata) in the South Atlantic Bight

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In the western North Atlantic, the winter distribution of minke whales (Balaenoptera acutorostrata), and the location of their calving grounds, are poorly known. Mitchell (1991) used rare sightings of adults and calves to suggest that minke whales winter from the West Indies east to Bermuda. Here we report recent survey data that suggest minke whales also utilize offshore waters of the South Atlantic Bight during winter. We conducted monthly aerial and long‐term acoustic surveys at two offshore sites ‐ Onslow Bay, NC and Jacksonville, FL ‐ fom June 2007 to April 2011, and January 2009 to April 2011, respectively. Minke whales were visually detected twice at the Onslow site and nine times at the Jacksonville site, during the months from December to February. Calves were observed a single time at each of the two survey sites. At each site the number of acoustic detections exceeded visual observations; minke whales were acoustically detected from November through April. A review of minke whale sightings (n= 22) made available by the North Atlantic Right Whale Consortium (1980-2010) suggests a similar seasonal and geographical distribution pattern in the mid‐ and southeast Atlantic. Since 1992, all nine recorded strandings of minke whales in the southeast US have been of calves, and seven of these stranded in winter or spring (data provided by NOAA SER). These recent data add to the results of Mitchell (1991) and suggest that the winter migratory and/or calving grounds extend to the offshore waters from North Carolina to Florida.