Tudor Wharf Draft Environmental Impact Report EOEA # 6744 



the mixed-aged pair) . These findings are 

 consistent with observations of late nesting 

 cohorts of other species (Massey and Atwood 

 1981, Coulson and White 1958). 



Habitat Use in Boston Harbor 



Information regarding the use of Boston 

 Harbor by black-crovmed night herons is 

 scarce (Hatch, LEC communication) . What 

 information is known is anecdotal in nature. 

 The following information is documented by 

 scientific publications or reports of 

 reputable scientists. 



Outer Islands 



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 

 (Hatch 1982) . 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, occurred 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) (Appendix A) . 



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 (LEC observation) to consist 

 principally of younger birds in their first 

 or second winter plumage. 



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