302 Memoir Sears Foundation for Marine Research 



as taken in the Gulf of Maine, and schools of them have been seined from time to time 

 in summer and autumn, even in December, at various places along the Maine coast, 

 where they have been the object of a frozen-fish industry in some years. Immature 

 fish (0.5-2.5 pounds) sometimes congregate also along the Maine coast and are more 

 or less common in the Massachusetts Bay region. 



Clearly these Gulf of Maine fish are far too numerous to be derived only from 

 the streams of the Bay of Fundy, as was formerly considered likely {16: 1 16). Recently, 

 extensive tagging experiments (75: iii, ftn. 18—20; 124) have shown that, while 

 some of them come from as far south as the Altamaha River, Georgia, others come from 

 as far north as the St. Lawrence estuary, both of these contingents to fatten in the 

 Gulf. By the end of December, however, they have vanished, not to reappear anywhere 

 on the coast until the onset of the next spawning season, when the maturing fish return 

 to the rivers of their native watersheds. 



Like salmon and alewives, American Shad spend most of their life in the sea and 

 make most of their growth there, but where they winter remains to be discovered. 

 While in the sea, Shad are schooling fish, often in the thousands, and they never re- 

 enter fresh water until they return to spawn, although they may appear in brackish 

 estuaries. They have been taken 25-90 miles out off southern New England, 1 10 miles 

 out on Georges Bank, 40-50 miles out off the coast of Maine, and 50-60 miles off 

 eastern Nova Scotia, and as deep as 50-68 fms. 



Food. The diet of 14 young fish, 43-60 mm long, from fresh water of the 

 Potomac River, consisted chiefly of adult and larval insects and ostracods, and in 

 one instance a small fish {^g: 95). Larger juveniles, 100-150 mm long, caught in 

 Chesapeake Bay, presumably while en route to the sea, had fed mostly on Mysis, although 

 one stomach contained fragments of a small fish, and another fragments of plant tissue. 



Working with young specimens from the Shubenacadie River, tributary to the 

 Bay of Fundy and its estuary, Leim found that the first food taken by larvae 1 1 mm 

 long consisted of midge larvae (Chironomidae), while the somewhat larger larvae had 

 fed principally on mature and immature copepods (81: 16). In fact, these organisms 

 constituted the chief food of the young up to the time of transformation, with the 

 relative abundance of these forms in a particular locality determining which food pre- 

 dominated. Dr. Leim's data show also that young adults taken in the same general 

 vicinity continued to subsist principally on these same organisms. Other foods ingested 

 consisted of ostracods, amphipods, insects, and fish. 



Little or no food has been found in the stomachs of those caught while in fresh 

 water en route to their spawning grounds, indicating that these fish, like salmon, do 

 not ordinarily feed then. However, there are some records showing that adults occasion- 

 ally do take food while in fresh water, at least late during the spawning season. They 

 will often take a live minnow or an artificial fly when working upstream on their 

 spawning run. 



Many kinds of food have been found in the stomachs of those taken in salt water 

 in estuaries and bays north of Cape Cod. But southward, examples are rarely obtainable 



