E 

 o 



■♦-» 



(O 



1000 -| 



500- 



100- 



40- 



30- 



20 



10 







X 

 X 

 X 



X 

 X 

 X 



X 

 X 



1 1 1 1 1 \ 1 I 



JFMAMJJAS 



137 



118 



111 



95 



77 



h 54 



19 







^-» 



E 

 o 



O N D 



month 



1=0.1-1.0 



MEAN NUMBER OF INDIVIDUALS OBSERVED PER HOUR 



X = ZONE NOT SAMPLED IN THIS MONTH 



Figure 22. 



Seasonal abundance and seaward distribution patterns of the 

 iceland gull in the northern Chesapeake Bight, 1971-1977. 



GREAT BLACK-BACKED GULL (Larus narinus ) 



Status . --Uncommon winter visitant from November through April over entire 

 Continental Shelf. Pare offshore in summer (Fig. 23). It is a casual breeder 

 but increasing in number along the Delmarva Peninsula (Armistead 1975). 



Maximum counts . --Approximately 260 in 9.5 h, 

 December 1977; 110 in 1.5 h, along the edge of 

 Baltimore Canyon northeast to 38°57'N, 73°00'W, 5 

 2-57 km ENE Ocean City, 3 March 1973; 36 in 11.5 

 11 April 1976. 



2-111 km ESE Ocean City, 3 

 the Continental Shelf from 

 February 1977; 75 in 10 h, 

 h, 2-113 km ESE Ocean City, 



Remarks . --Most commonly gathered around fishing vessels and chum slicks, 

 Only immatures were observed offshore during the summer. 



32 



