COMMON 

 PUFFIN 



BLACK 

 GUILLEMOT 



RAZORBILL 



MONTH 

 APRIL I MAY I JUNE | JULY [ AUG. | SEPT. 



1 



ARRIVAL < ^ 1 y 



EGG LAYING ^ 23 

 INCUBATION ^^ — 



BROODING <C r ^ y ^~ 



FLEDGING < Z ^ ^ — 



EGG LAYING ^ ^ 



INCUBATION 



HATCHING 

 BROODING 



4,5 



4.5 



> 



FLEDGING < f 4 ^ 



EGG LAYING 

 INCUBATION 



2.6 



BROODING 



2.7 



REFERENCE: 



1 Brown 1911 



2 Bent 1919 



3 Pettingill 1939 



4 Palmer 1949 



5 Winn 1947 



6 Tufts 1961 



7 Buchheister (unpublished) 



Figure 8. Estimated breeding chronology of three species of alcids nesting in Maine. 



43 



