Data were collected during aerial surveys carried out at low tides in June and August 1994-1997, 2000 and 2001. June and August are respectively pupping and moulting seasons, when the haulout sites are intensively used by seals. Features in this layer show the Grey seal distribution and mean abundance for all aerial surveys (tables 4 and 6, figures 4 and 6 from Robillard et al. 2005). In the estuary, areas of high abundance have more than 25 individuals, areas of medium abundance have between 5 and 25 individuals and areas of low abundance have fewer than 5 individuals. In the Gulf, areas of high abundance have more than 70 individuals and areas of medium to low abundance have fewer than 70 individuals.
Data are valid only during summer because Grey seals in the Estuary and northern Gulf migrate to the southern Gulf of St. Lawrence in the fall. These seals will spend the winter on Sable Island, on the ice shelf in the Northumberland Strait or on neighboring islands. During the summer, in the Estuary and the Gulf of St. Lawrence, its distribution is not uniform between the different concentration areas identified, but it is similar between June and August. However, there are some areas where Grey seals are more abundant in August than in June. Abundance classes are arbitrary but fit with the published results of haul-out sites utilization from Robillard et al. (2005). Data shown are a picture of the situation in 2005 because it is the most recent mapping available for this species.
Data sources and references:
Lavigueur, L., Hammill, M.O., and Asselin, S. 1993. Distribution et biologie des phoques et autres mammifères marins dans la région du parc marin du Saguenay. Rapp. manus. can. sci. halieut. aquat. 2220: vi + 40.
Lesage, V., and Hammill, M.O. 2001. The status of the grey seal, Halichoerus grypus, in the Northwest Atlantic. Can. Field-Nat. 115(4): 653-662.
Robillard, A., V. Lesage, and M.O. Hammill. 2005. Distribution and abundance of harbour seals (Phoca vitulina concolor) and grey seals (Halichoerus grypus) in the Estuary and Gulf of St. Lawrence, 1994–2001. Can. Tech. Rep. Fish. Aquat. Sci. 2613: 152 pp.