may have been depleted because as Kanshilov (1955) suggests, P^. cumis may 

 feed exclusively on B^. infundibulum . 



17.) Molluscan larvae 



Bivalve larvae were most abundant in the summer during the warm season. 

 Several different species were dominant (i.e., abundant) in Penobscot Bay: 

 Mya arenaria , Mytilus edulis , Mercenaria mercenaria . No peaks of reproduction 

 were recorded (Bertrand 1977) . In the Damariscotta River estuary two peaks 

 were recorded: the first in spring and the second in autumn; and they were 

 of equal magnitude (Lee 1974) . 



Gastropod larvae were not identified to species in Penobscot Bay 

 (Bertrand 1977). The major abundant peak occurred in August-September, 

 however they were present from June through September (Bertrand 1977) . 

 Abundances were less than for bivalve larvae (Bertrand 1977) . Legare and 

 Maclellan (1960) reported gastropod larvae in the spring, summer, and a few 

 in autumn for Passamaquoddy and Cobscook Bays. 



18.) Polychaete larvae 



Polychaete larvae (setiger stage) were present in Penobscot Bay in the 

 plankton from spring to mid-summer in 1975 and in November-December 1974 

 (Bertrand 1977). The most abundant polychaetes were Polydora spp. and 

 Nereis spp. (Bertrand 1977). Bertrand (1977) feels that his data suggest 

 that benthic polychaetes in the Bay probably spawn in spring and early 

 summer. Peaks in numbers of polychaete larvae in spring and late summer are 

 also found in the Damariscotta River estuary (Lee 1974) . Polychaete larvae 

 had a similar seasonal pattern of occurrence in Passamaquoddy Bay and 

 Cobscook Bay (Legare and Maclellan 1960) . 



19.) Special Interaction: 



Fishing and an Oceanic Coelenterate 



The siphonophore, Nanonia cara, was found in great abundances off 

 Boothbay Harbor and Portland (Rogers 1976) . Fishing nets became clogged 

 and fish catches declined dramatically. Rogers (1976) attributes this 

 "bloom" to warmer than average temperatures. Bigelow (1926) notes that this 

 species is widely distributed in the Gulf of Maine with maximum abundances 

 occurring in summer. Bertrand (1977) reported that N. cara occurs in 

 Penobscot Bay erratically and in low numbers. Since immature stages were 

 collected, Bertrand (1977) feels that there is a native population in the 

 bay. Temperatures from Penobscot Bay east are probably too low to induce 

 the bloom phenomenon which occurred in western Maine. 



4-F-8 



