SIGHT OBSERVATIONS OF IVORY GULLS 
     
     ON PRINCE EDWARD ISLAND 
     
    
   
   
    
     by Martin K. McNicholl, 320 Markham St., Tbronto, Ontario M6G 2K9 
     
    
   
   
    
     At 15:30 on 16 April 1977, I was birdwatching in Prince Edward Island 
     
     National Park, P.E.I., when I noticed a small flock of gulls roosting beside a 
     
     small pond behind sand dunes. The flock included 18 Great Blackbacks, 12 Herring, 
     
     2 Iceland, 2 Ring-billeds, and one smaller, entirely white gull with black legs 
     
     and yellow—tipped black bill which could only be an Ivory. This bird was clearly 
     
     smaller than the Ring-billeds beside it, and thus smaller than any other primarily 
     
     white gull, and the other features noted are diagnostic (see Peterson 1980). When 
     
     all the gulls rose in flight, the Ivory Gull also flew more tern-like than the 
     
     others. At 14:20 on 24 April, I was at the cormorant colony at Cape Tryon with 
     
     Lawrence Gray, when a bird with the same field marks flew by at less than 10 m 
     
     from us. we observed the same field marks, and noted that the’gull was slightly 
     
     larger than the Rock Doves that nest there. As we did not obtain photographic 
     
     evidence, these two records must remain hypothetical, but the distinctive field 
     
     marks make our sightings highly probable. 
     
    

    
     Godfrey (1954) listed the Ivory Gull as hypothetical in Prince Edward Island, 
     
     a status retained in the latest provincial check-list (Anonymous 1978). However, 
     
     Godfrey (1954) notes that even this status is based on vague reports without well 
     
     substantiated details. Thus, our records at least increase the probability that 
     
     this species does occur on the island. 
     
    

    
     Ivory Gulls occur regularly in winter along Labrador and Newfoundland, some- 
     
     times in large numbers (Bent 1921; Finch 1975, 1976a,c; Fbrster 1983; Godfrey 
     
     1966; Vickery 1977a,b, 1978, 1979a,b, 1981a,b, 1982), and have been seen off 
     
     Labrador even in summer (Brown 1976). They occasionally turn up on Christmas 
     
     Bird counts in various sites in the Maritimes (Table 1), and sometimes stray to 
     
     New Brunswick (Bent 1921; Finch 1976a; Godfrey 1966; Squires 1976), Nova Scotia 
     
     (Bagg and Emery 1964; Finch 1970,1976b; Godfrey 1966; Neil 1983; Tufts 1973; 
     
     Vickery 1978, 1979a), and the northern coast of the Gulf of St. Lawrence (Bent 
     
     1921; Godfrey 1966; Lewis 1941; Taverner 1940; Tanguay 1949). These records 
     
     suggest that it is a rare, but expected winter visitor throughout the Maritimes. 
     
    

    
     Our two observations, the number of sightings of Ivory Gulls elsewhere in 
     
     the Maritimes, and the recent report of a Lesser Black-backed Gull on Prince 
     
     Edward Island (Hogan 1983) all suggest that observers on the island should keep 
     
     a careful lookout for unusual gulls there. 
     
    
   
   
    
     Acknowledgements 
     
     The two Ivory Gull sightings reported in this note took place while I was assisting 
     
    
   
   
    
     Geoffrey G. Hogan in cormorant studies for his M.Sc. thesis at Brock University, 
     
     St. Cbtharines, Ont. under Ralph D. Mbrris. 
     
    
   
   
    
     Literature Cited 
     
     Anonymous. 1978. Prince Edward Island field check- 
     
     list of birds, 2nd edition. P.E.I. Dept. of 
     
     Tourism, Parks and Conservation, Charlottetown. 
     
     Bagg, A.M. and R.P. Emery. 1964. Winter season. Dec. 1, 
     
     1963—Mar. 31, 1964. Audubon Field Notes 18:334-340. 
     
     Bent, A.C. 1921. Life histories of North American gulls 
     
     and terns. U.S. Natl. Mus. Bull. 113 (reprinted 
     
     by Dover, 1963). 
     
    
   
   
    
       
     
    
   
   
    
       
     
    
   
   
    
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