September 2000 LONG-FINNED PILOT WHALE (Globicephala melas): Western North Atlantic Stock

• Main Authors: Stock Definition, Geographic Range
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Payne; Iceland; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.294.5975; http://www.nmfs.noaa.gov/pr/pdfs/sars/ao2000whpl-wn.pdf

There are two species of pilot whales in the Western Atlantic — the Atlantic or long-finned pilot whale, Globicephala melas, and the sh ort-finned pilot whale, G. macrorhynchus. These species are difficult to identify to the species level at sea; therefore, some of the descriptive material below refers to Globicephala sp., and is identified as such. The species boundary is considered to be in the New Jersey to Cape Hatteras area. Sightings north of this area are likely G. melas. Pilot whales (Globicephala sp.) are distributed principally along the continental shelf ed ge in the winter and early spring off the northeast USA coast, (CETAP 1 982; Payne and Heinem ann 1993). In late sp ring, pilot whales move onto Georges Bank and into the Gulf of Maine and m ore northern waters, and remain in these areas through late autumn (CETAP 1982; Payne and Heinem ann 1993). In general, pilot whales generally occupy areas of high relief or submerged banks. They are also associated with the Gulf Stream north wall and thermal fronts along the continental shelf edge (Waring et al. 1992; N MFS unpub lished data). The long-finned pilot whale is distributed from North Carolina to Iceland and possibly the Baltic Sea (Sergeant 1962; Leatherwood et al. 1976; Abend 1993). The stock structure of the No rth Atlantic population is currently unknown (Anon. 1993a); how ever, several recently initiated genetic studies and p roposed North A tlantic sighting surveys w ill likely provide information required to delineate stock boundaries. POPULATION SIZE The total number of long-finned pilot whales off the eastern USA and Canadian Atlantic coast is unknown, although ten estimates from selected regions of the habitat do exist for select time periods. Sightings were almost ex clusively in the continental shelf edge and continental slope areas (Figure 1). Two estimates were derived from catch data and population models that estimated the abundance of the entire stock. Seven seasonal estimates are available from selected regions in USA waters ...