10000 



1000 



u 



u 



a 



CA 



cc 



BLACK GUILLEMOT 



1900 1910 



1920 1930 1940 

 YEAR 



1950 



1960 



1970 



Figure 11. Trends in nesting populations of three species of alcids in Maine (excluding Machias Seal Island) since 1900. Breeding popula- 

 tions were nonexistent or very low prior to the first data point. 



51 



