Great Lakes area. 

 Green Bay and Lake Michigan 

 Black-crowned night-heron, 

 Nycticorax nycticorax 

 Whole 

 1982 

 1978 

 Double-crested cormorant, 

 Phalacrocorax auritus 



Whole, 1983 

 Forster's tern. Sterna forsteri 

 Wisconsin, 1981 



Egg 



Green Bay 

 Lake Poygan 



21 

 (12-59) 



Stalling et al. 1985a 



47 

 9 



13 



