Winter distribution of harp seals ( Phoca groenlandica ) off eastern Newfoundland and southern Labrador

Abstract

The winter distribution of Newfoundland harp seals (Phoca groenlandica) was determined using sighting data collected during January and February from 1991 to 1995 aboard research vessels that covered the northeastern continental shelf between 46–55°N and 47–54°W. Data were standardized for effort and sighting conditions. Visual appraisals of data were made using a Geographical Information System. In contrast to historical perceptions, offshore areas such as the northern part of the Grand Banks (48–49°N and 49–51°W) appear to be extremely important to wintering harp seals. Southeastern shifts in distribution appear to have occurred since the early 1990s, particularly between the 1991–1993 and 1994–1995 periods. This southern shift in range agrees with the recent increase in extralimital occurrences of harp seals along the North American east coast. Concurrent changes in environmental conditions suggest that physical and biological factors may influence the distribution of this population.