principally inhabit cool, boggy waters. Good coverage of the general 

 distribution and habitat preferences of freshwater fishes is found in Scarola 

 (1973), Everhart (1958), and Scott and Crossman (1973). 



Seasonal Occurrence and Migration 



Water temperature is one of the major factors controlling the seasonal and 

 daily movements of fish populations. Many fish species have preferred 

 temperature ranges and move in response to seasonal and local changes in 

 temperature. Gulf of Maine waters have a narrower annual temperature range 

 than the neighboring mid-Atlantic Bight waters to the south. Colton (1972) 

 discusses the effects of these temperature trends on the distribution and 

 migration of certain marine fishes in the Gulf of Maine. The relatively 

 stable seasonal temperatures tend to support a high proportion of resident 

 marine fishes. The mid-Atlantic waters, on the other hand, support few 

 permanent residents and are inhabited by continuously shifting populations of 

 southern (temperate) migrants and some northern species. 



Some southern migrants to the mid-Atlantic Bight waters follow the summer 

 thermoclines up into the Gulf of Maine. Many of these species are present in 

 sufficient numbers to play a significant role in the ecology of coastal Maine. 

 Common summer migrants inshore and along the coast are spiny dogfish, scup, 

 silver hake, spotted hake, red hake, white hake, tautog, American shad, 

 hickory shad, striped bass, menhaden, blueback herring, bluefish, Atlantic 

 mackerel, butterfish and bluefin tuna. Many of these species (e.g., tuna, 

 bluefish, mackerel, and striped bass) are important sport fishes in Maine and 

 other Atlantic states. Not all of these species reach eastern Maine and 

 Canada. Many are uncommon east of the Penobscot Bay area (scup, spotted hake, 

 hickory shad, tautog, butterfish, and bluefish). Most of these summer 

 migrants leave coastal Maine with the onset of cooling autumn water 

 temperatures and disperse to the south. There is an additional winter 

 dispersal of cod and pollock from the Gulf of Maine to waters south of Cape 

 Cod but their numbers do not rival the summer migrants from the mid-Atlantic 

 (TRIGOM 1974). 



Most of the resident fish species exhibit some form of seasonal and/or daily 

 movements, either inshore to offshore or from shallow flats to deeper water, 

 in response to changes in temperature. Many resident marine and estuarine 

 fishes move offshore into deeper (warmer) waters to overwinter (e.g., the 

 flounders, the skates, cunner, lumpfish, and alewife) . Resident populations 

 of brown, brook, and rainbow trout show marked movements along river reaches, 

 in and out of the lakes through connecting streams. Of special interest are 

 the resident anadromous and catadromous fishes. 



Anadromous and Catadromous Fish Distribution 



Coastal Maine supports relatively healthy and diverse populations of 

 anadromous species in comparison with many other Atlantic coastal areas. 

 Resident anadromous fishes include the shortnose and Atlantic sturgeon (both 

 are rare and the shortnose is an endangered species), alewife (common 

 throughout), rainbow smelt (common throughout), sea lamprey (common in 

 midcoastal and eastern Maine), and Atlantic salmon (rare in Maine but its 

 populations are recovering in the Sheepscot, Ducktrap, Machias, East Machias, 

 Dennys , and Pleasant Rivers, and Penobscot, Kennebec, and Narraguagus 



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