listed 8,000 pairs at 10 colonies in 1936 (Figure 10). In 1972, 2,900 pairs of 

 Arctic terns were estimated to be nesting on four islands in Maine (Drury 

 1973). In 1977, nine Arctic tern colonies were located which had a combined 

 estimated breeding population of 1,640 pairs. 



Roseate terns . Nisbet (1971) indicated that roseate terns in Maine are 

 at the northern limit of their range. A small number have nested in western 

 Maine for at least the last 40 years. The most persistent colony is on North 

 Sugarloaf Island at the mouth of the Kennebec River, where they nest with 

 common and Arctic terns. A few pairs of roseate terns have nested in 

 association with common terns from time to time at other locations. 



In 1931 Norton (unpublished) reported 275 pairs of roseates in 2 colonies 

 on Stratton Island, and North Sugarloaf Island, and 1 bird on Machias Seal 

 Island. North Sugarloaf recently has been the largest colony. Morse (1957) 

 reported five pairs in 1956. In 1971, 150 pairs were seen and in 1972, 75 

 pairs. In 1977 roseate terns were found nesting on North Sugarloaf, Petit 

 Manan, and Beach islands with a combined population estimate of 80 pairs. 



Least tern . The least tern has never been abundant in Maine, probably 

 reaching a high population of 50-60 pairs in 1972 (Dorr, unpublished). Like 

 the roseate tern, it is at the northern limit of its nesting range. Only two 

 colonies were found during this inventory, and they were located on mainland 

 beaches. H. Tyler (personal communication) reports that approximately 10 

 pairs nested on Popham Beach in 1976. In 1977 this small colony moved from 

 Popham Beach westward to Sprague River Beach. Fourteen pairs also nested 

 on Goose Rocks Beach in 1977. 



Razorbill Nesting razorbills have been scarce in Maine in this century 

 (FiguTe 11). Razorbills have been seen on a number of islands but until 

 recently have nested only on Matinicus Rock. 



Norton (1923) reported that between 1894 and 1923 no razorbills nested 

 in Maine. Five pairs nested on Matinicus Rock in 1968 to 1970, and nine 

 pairs in 1974 (C. Buchheister, unpublished). Drury (1973) counted 40 

 razorbills on Old Man Island in May 1973. However, he did not find evidence 

 of nesting. In July 1976, Old Man Island was visited and young razorbills 

 were seen on the island. We determined that at least 4 pairs had young and 

 about 50 adults were in the vicinity. In May 1977 numerous razorbills were 

 seen on or around the island and several appeared to be nesting; a close 

 inspection was not made due to the vulnerability of the razorbill eggs to 

 gulls. Maine now has two active nesting colonies of razorbills totaling about 

 25 pairs. 



Black guillemot The guillemot population has increased on the Maine 

 coast during recent decades (Figure 11). This increase has been associated 

 primarily with the establishment of new colonies. Norton (unpublished) re- 

 ported that in 1903 guillemots nested on 14 islands and totaled about 75 pairs. 

 His survey in 1931 recorded 24 nesting islands with a total population of 

 about 300 pairs. The total breeding population was estimated to be approxi- 

 mately 3,400 pairs in 1970-1972 (Drury 1973). 



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