Tudor Wharf Draft Environmental Impact Report EOEA # 6744 



7.3 Breeding Areas 



Large breeding colonies of black-crowned 

 night herons occur on the islands of 

 Boston Harbor; specifically, Middle 

 Brewster, Outer Brewster, Calf Island and 

 Spectacle Island. The herons have been 

 known to utilize the inner harbor for 

 feeding and roosting sites, principally 

 during the non-breeding season; 

 typically, late August through early 

 April. The largest black-crowned night 

 heron rookery, which has exceeded 3 00 

 breeding pairs, occurs on Spectacle 

 Island. Other islands reporting breeding 

 pairs of herons are Middle Brewster 

 Island (20-154 pair) and Calf Island 

 (several pair) and more recently on Outer 

 Brewster Island (several pair) (See 

 Exhibit 29) . 



Herons begin to assemble at their 

 breeding areas during the beginning part 

 of April and remain there until young 

 birds fledge in early June. The largest 

 portion of the Boston Harbor population 

 of black-crowned night herons migrate 

 south beginning in August and September. 

 A small portion of the population remain 

 in the Boston Harbor area during the 

 winter months. The population appeared to 

 consist principally of younger birds in 

 their first or second winter plumage. 



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