In winter, many species remain part 

 of a year-round resident population 

 (Figure 13). The winter and smooth 

 flounder remain in the estuaries, with the 

 winter flounder, in particular, moving 

 into shallower parts of the area during 

 fall and winter. White perch move from 

 their habitat upstream in slightly brack- 

 ish and freshwater to more brackish and 

 oceanic conditions in estuaries during the 

 winter. Some boreal-Arctic species (e.g., 

 alligatorfish) migrate southward into 

 these waters in the winter. 



There are three major differences 

 between the fish communities north and 

 south of Cape Cod: a greater proportion 

 of the fish in the Gulf of Maine are year- 

 round resident species, so that during the 

 summer, lacking migrants from the south, 

 fish species diversity is generally lower 



than in southern New England; gadids are 

 more common to the inshore Gulf of Maine 

 region, while in southern waters their 

 distribution is largely restricted to 

 offshore waters; migration and spawning 

 activities tend to occur later in northern 

 waters because Gulf of Maine water temper- 

 atures increase later than those in south- 

 ern New England. 



4.6 THE DEPENDENCE AND ROLE OF FISH ON 

 TIDAL FLATS 



Many fish utilize shallow-water 

 coastal habitats as feeding and nursery 

 grounds. The reproductive activities of 

 these species coincide with periods of 

 maximum food production, and predation 

 rates on juvenile fish are apparently 

 lower in shallow-water than adjacent 

 deeper water areas. As the fish grow. 



The longhorned sculpin, Myoxocephalus octodecemstinosus , (this specimen ZU cm long) is 

 distinguished from the other western North Atlantic sculpins by a long, sharp spine on 

 the preopercular bone. In the northern part of its range it is a year-round resident 

 moving into deeper waters in cold weather and back inshore in spring. In the southern 

 part of its range, it remains in deeper water during the warmer months and moves 

 inshore with declining water temperatures. Longhorned sculpins are winter spawners in 

 New England, laying adhesive egg clumps on vegetation. Photo by R.E. DeGoursey, Uni- 

 versity of Connecticut. 



47 



