During the winter months Maine's cetaceans either migrate south to breeding 

 grounds (e.g., the humpback whales, right whales, and minke whales) or move 

 offshore where waters do not become as cold as along the coast (pilot whales 

 and some finback whales). The winter ranges of the other cetaceans are not 

 well known. 



Pinnipeds 



The gray seal and the harbor seal are currently the only pinnipeds of the 

 Atlantic coastal waters of the United States (Katona 1977; and Richardson 

 1978) . The harbor seal is the dominant seal of coastal Maine and can be 

 sighted throughout the year on small islands and half-tide ledges coastwide. 

 Censuses conducted by Richardson (1973 to 1976) reveal a harbor seal 

 population of about 6000 that is well distributed in all embayments of the 

 Maine coast, with somewhat greater densities from Casco Bay to Pemaquid 

 (region 2), the approaches to Penobscot and Blue Hill Bays (regions 4 and 5), 

 and in the Jonesport, Englishman Bay, and Machias Bay areas (region 6; table 

 13-3). The mean density was 12 seals per square nautical mile surveyed (9/sq 

 mi; 3.5/sq km). Richardson (1973a) also identified harbor seal pups. The 

 highest numbers of pups were in regions 1 (87) and 5 (79). It is not known 

 whether discrete populations or subpopulations function within these different 

 embayments. The sites inventoried and number of seals observed are presented 

 in appendix table 1 . 



Haulouts are areas used by seals for resting, sunning, feeding, breeding, and 

 pupping. They are usually small islands lacking terrestrial vegetation but 

 having some areas that are exposed at mean high tide, or half-tide ledges that 

 are completely submerged at mean high tide. In either case the intertidal 

 area is usually densely covered with macroalgae (fucoids, Chondrus sp.) and 

 the approach to the water is a gentle slope. Haulouts invariably are 

 surrounded by water deep enough for escape even at low tide. 



Although whelping and rearing of young occur at offshore as well as estuarine 

 sites, those marine haulouts exposed to high energy wind and wave action 

 appear to be utilized more for foraging and socialization. Less exposed, up- 

 estuary haulouts appear to be favored for whelping, mating, and use during 

 molting (Richardson 1973a) . Seasonal censuses of harbor seals conducted by 

 Richardson reveal up-estuary migration of colonies in spring, with subsequent 

 segregation of age and sex classes at whelping sites. Down-estuary movement 

 occurs in the late fall, following breeding and molting. Greater numbers of 

 seals are found at more protected, up-estuary haulouts during late spring and 

 summer, whereas they utilize more exposed haulouts in deeper, ice-free water 

 during winter months. The extent to which water temperature, food 

 availability, and behavior affect the seasonal redistribution of these 

 colonies has not been documented. 



The distribution of seal haulouts among regions in the characterization area, 

 based on Richardson (1973a), is summarized in table 13-4. Over 50% of these 

 haulout areas are in regions 4 and 5. Richardson (1975) identified 44 seal 

 haulout areas in Maine (41 in the characterization area) known to be regularly 

 utilized by seals and judged to be significant based on one or more of the 

 following criteria: 



13-8 



