DOUBLE- 

 CRESTED 

 CORMORANT 



COMMON 

 EIDER 



GREAT 



BLUE 



HERON 



MONTH 

 APRIL I MAY I JUNE | JULY | AUG. 



SEPT. 



< 



1.2 



EGG LAYING 

 INCUBATION 



HATCHING < ^ 1,2 2 > 



BROODING 



1.2 



FLEDGING 



< ' > 



3,4 



EGG LAYING 

 INCUBATION 



HATCHING 

 BROODING 



3,4,5 



> 



3.4 



> 



FLEDGING 



> 



< 



ARRIVAL 



< 



EGG LAYING 

 INCUBATION 



HATCHING 



< 



FLEDGING 



REFERENCE: 



1 Palmer 1962 



2 Mendall1936 



3 Choate 1966 



4 Clark 1968: p55-56 



5 Gross 1938 



6 Palmer 1976 



7 H. Tyler (unpublished) 



Figure 5. Estimated breeding chronology of double-crested cormorants, common eiders, and great blue herons nesting in Maine. 



40 



