592 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



ponds from the largest to the smallest size, to reach which it will, when 

 necessary, push up extremely small brooks. 



It is a notable characteristic of all these migratory species to return, 

 for the purpose of procreation, to the very waters where they themselves 

 were born. Thus, each river, and, in general, each branch, each lake, 

 and each pond, has its own army of migrating fishes, feeding and grow- 

 ing in the sea, and sending oif each season a detachment to the parent- 

 waters to continue the work of reproduction. The instinct that leads 

 them into their native waters, though not strictly infallible, is so remark- 

 ably strong that those fishes that stray from the true way constitute a 

 very small percentage of the whole army. Ilhistrations of this truth are 

 to be found in many marked instances. The salmon of the Kennebec, 

 where a small area of spawning-ground is still accessible, yearly pursue 

 the course toward the upper waters of that river, so rarely turning oft 

 into the tributary, Androscoggin, that hundreds are caught in the for- 

 mer to one in the latter, though in natural fitness for salmon-breeding, 

 aside from the facilities for ascending it, the Androscoggin is certainly 

 not inferior. In a comparison of the Penobscot and Union, the case is 

 stronger still. This established trait has an important bearing on the 

 question of the ascent of migratory fishes past an obstruction that 

 has been for generations impassable. Though known facts hardly war. 

 rant the conclusion that fishes will not often try to ascend to a higher 

 point on the river than was reached by their parents, there is nothing 

 to forbid the conclusion that they have less inclination to seek the higher 

 waters than they would have had if they had been born there. 



The behavior of these three kinds of fishes while in the vicinity of 

 obstructions is found to correspond in some degree to the range of their 

 migrations. Salmon and alewives, whose migrations extend to higher 

 and smaller streams than those frequented by shad, are found to take 

 more readily to narrow passage-ways than the latter. 



Alewives are hardy, venturesome, little fish, following the main stream 

 where it is practicable and easy, but ready enough to turn aside and 

 seek a narrow way around a difficult point. They have been known to 

 rush up a fish-way between the legs of the carpenter who was giving it the 

 finishing strokes, and a trough only eight inches wide, divided into com- 

 partments, which were connected by passage-ways only four inches wide, 

 has afforded ready passage to large numbers of them.* They exhibit a 

 strong, gregarious instinct, moving in dense bodies as if by a common 

 impulse. They always move over falls by day, and their favorite time 

 is a bright sunny afternoon. On the approach of night, they drop back 

 and rest in still pools until the next day is well advanced. So great is 

 their inclination at night-fall to yield a little to the current that some- 

 times a large body of fish that has passed out of a fish-way just at dusk 

 will settle back into it and rest in its bays, if they are easy enough, till 



*Report of the Massachusetts Commissioners on Inland Fisheries, January, 1869. p. 6. 



