Stellwagen Bank Final EIS and Management Plan 



Page 33 



Shearwaters - Four species of shearwaters occur 

 with regularity over the Stellwagen Bank/Georges 

 Bank area: Cory's shearwater (Calonectris 

 diomedea); Greater shearwater (Puffinus gravis '): 

 Sooty shearwater (P, griseus l: and Manx 

 shearwater (P, pufFuius ). A fifth species, 

 Audubon's shearwater (Puffinus Jherminieri), 

 normally is found on southern edges of Georges 

 Bank during the summer. 



Cory's shearwaters are abundant in New England 

 waters generally from July until October; and in 

 some years significant numbers of this species have 

 moved into the Gulf of Maine and stayed until the 

 autumn (Powers and Brown, 1983). The largest 

 local concentrations have occasionally been 

 recorded at 30-100 birds/km^ (Powers, 1983). The 

 species feeds at or near the surface as secondary 

 and tertiary carnivores on fish, fish larvae, 

 cephalopods, and crustaceans. 



The Greater shearwater is highly abundant over 

 Georges Bank, beginning in May and peaking in 

 June and July, when densities may reach 25 

 birds/km". The species is most numerous over 

 Stellwagen Bank during summer and autumn 

 months. Like the Cory's, the Greater shearwater 

 feeds as a tertiary carnivore on fish and 

 cephalopods; as a secondary carnivore on 

 crustaceans; and as a scavenger on offal from 

 fishing vessels. 



Between May and September, Sooty shearwaters 

 migrate in a clockwise manner around the North 

 Atlantic basin; they are abundant on Georges Bank 

 from late May to mid-July, and are found over 

 Stellwagen Bank during the summer months. 

 Typically, the species feeds at or near the surface as 

 a secondary or tertiary carnivore on fish, 

 cephalopods, and crustaceans; however, this species 

 does not appear as frequently in association with 

 fishing vessels as other shearwaters (Wahl and 

 Heinemann, 1979). 



Manx shearwaters occur over Georges Bank from 

 June to October (Powers and Brown, 1983); and are 

 occasionally seen over Stellwagen Bank during 

 summer months. Like other shearwaters, the Manx 

 is a secondary and a tertiary carnivore, feeding on 

 small fish, cephalopods, crustaceans, and probably 



offal. 



Storm Petrels - Of the two species of storm petrels 

 occurring in and around the Stellwagen Bank area, 

 Wilson's (Oceanites oceanicus ) and Leach's 

 (Oceanodroma Jeucorhoa), the Wilson's is by far 

 the more commonly-seen. 



Wilson's storm petrels arrive in the Gulf of Maine 

 by late May, and reside through the summer 

 months; this residency largely coincides with the 

 seasonal peak in zooplankton. The species is 

 primarily a surface-feeder on zooplankton, 

 euphausiids, and amphipods, and (to a lesser 

 degree) as a tertiary carnivore on small fish and 

 cephalopods. Also known as Mother Carey's chick 

 (Powers and Brown, 1983), the Wilson's storm 

 petrel is the second most abundant seabird species 

 during the summer over the Georges 

 Bank/Stellwagen Bank area. 



Leach's storm petrels are also found in this region 

 between April and November, although they are 

 more abundant on the Southern Scotian Shelf, to 

 the north. This is the only seabird species which 

 utilizes northern areas as breeding habitat, in 

 particular, the Bay of Fundy region (Powers and 

 Brown, 1983). 



Gannets and Cormorants - The Northern gannet 



(Sula bassanus) are tertiary carnivores feeding 

 almost exclusively on fish and squid, although the 

 species is known to scavenge offal from fishing 

 vessels and may also take fish directly from fishing 

 nets near the surface (Powers, 1983). Gannets are 

 most numerous in the Gulf of Maine, and in 

 particular over Stellwagen Bank and through the 

 Great South Channel. During winter-spring, large 

 concentrations of gannets have been observed 

 feeding in association with cetaceans (Payne and 

 Seltzer, 1986). 



Two species of cormorants occur very occasionally 

 over Stellwagen Bank; they are more typically 

 coastal inhabitants. 



The Great cormorant (Phalacrocorax carbo) and 

 the Double-crested cormorant (Phalacrocorax 

 auritus) exhibit migratory movements in the spring 

 and autumn in the western Gulf of Maine, and feed 



