1999 

 OUR LIVING OCEANS 



Fraser's dolphin. 



Coast (Richardson, 1976; KL-nney, 1994). The 

 overall geographic range throughout U.S. Atlan- 

 tic coast waters has not changed greatly during 

 the last century. 



Population Size 



Since passage ot the Marine Mammal Protec- 

 tion Act in 1972, the number of- seals along the 

 New England coast has increased nearly hvetold. 

 Coast-wide aerial surveys along the Maine coast 

 were conducted in May-Iimc during pupping in 

 1981, 1982, 1986, 1993, and 1997 (Ciilbert and 

 Stein, 1981; Gilbert and Wynne, 198.^; Gilbert 

 and Wynne, 1 984; Kenney, 1 994; and Gilbert and 

 Guldager, 1998). Aerial survey haul-out counts 

 (adults and pups) were 10,540 (1981), 9,3.^1 

 (1982), 12,940 (1986), 28,810 (1993), and 

 30,990 ( 1997). These niunbers are considered to 

 be minimum abundance estimates because they 

 are uncorrected tor animals in the water or out- 

 side the survey area. The annual increase since 

 1993 has been 1 .8 percent (Gilbert and ( luldager, 

 1 998). Since 1 98 1 , the average annual increase has 

 been 4.2 percent (Gilbert and Ciuldager, 1998), 

 about 50% ot the 8.9 percent annual increase es- 

 timated by Kenney (1994) from counts through 

 1993. Pup counts along the Maine coast during 

 the May-June period were: 676 (1981), 1,198 

 (1982), 1,713 (1986), 4,250 (1993), and 5,359 

 (1997). The 1997 estimate is 26 percent above 

 the 1993 value. Since 1981, the number ot pups 



along the Maine coast has increased at an annual 

 rate of 12.9 percent (Gilbert and Guldager, 1998). 



Increased abundance ot seals in wintering ar- 

 eas in southern New pjigland and New York has 

 also been documented m monnoring programs 

 conducted by a variety nongovernment organiza- 

 tions. C'anadian scientists counted 3,600 harbor 

 seals during an August 1992 aerial survey in the 

 Bay ot Pundy (Stobo and Fowler, 1 994), but noted 

 that the survey was not designed to obtain a popu- 

 lation estimate. 



Harbor seals, like gray seals, were bounty 

 hunted in New England waters until the late 

 1960's. This hunt may have caused the demise ot 

 this stock in U.S. waters (Katona et al., 1993). 

 Researchers and fishery observers have docu- 

 mented incidental mortality in several fisheries in 

 recent years, particularh' within the Cult ot Maine 

 (Waring et al., 1997). An unknown level ot mor- 

 tality also occurs in the mariculture industry (i.e. 

 salmon farming), in power plant intake pipes, and 

 by deliberate shooting (NMFS unpublished data^). 

 An unknown number of harbor seals have been 

 taken in Newfoundland and Labrador, Gulf of St. 

 Lawrence, and Bay ot Fundy groundtish gillnets, 

 Atlantic Canada and Greenland salmon gillnets, 

 Atlantic Canada cod traps. Bay ot Fundy herring 

 weirs, and from deliberate shooting (Read, 1994). 

 Estimated average annual mortality and serious in- 

 jury to this stock during 1990-93 are 602 (CV = 

 0.68), 231 (CV = 0.22), 373 (CV = 0.23), 698 

 (CV = 0.19), 1,330 (CV = 0.25), 1,179 (CV = 

 0.21 ), and 911 (CV = 0.27), respectively. 



Small numbers ot harbor seals regularly strand 

 during the winter period in southern New England 

 and Mid-Atlantic regions (NMFS, unpublished 

 data'). Sources ot mortality include human inter- 

 actions (boat strikes, fishing gear, power plant in- 

 take, aquaculture operations), storms, abandt)n- 

 ment by the mother, and disease (Katona et al., 

 1993; NMFS unpublished data'). In 1980, more 

 than 350 seals were found dead in the Cape Cod 

 area from an influenza outbreak (Geraci et al., 

 1981). The mininmni population estimate is 

 30,990 harbor seals (Waring et al., 1997). 



'Northeast Mshcries Scicncx ("enter. NMFS. 166 W.iter Street, 

 Woods Hole. MA 02S4.?. 



254 



