SOURCES OF MARINE FOOD. 
353 
I think that the food materials thus far mentioned, i. e., young fish, butter-fish, 
and squid, are closely interrelated, and that the young fish are again the central 
point, for one finds upon examining the stomachs of the butter-fish that they are 
carnivorous, feeding upon small fish; in fact, one was taken from a squeteague which 
was itself in the act of capturing a minnow, which stuck, half-swallowed, from its 
mouth. The squid, as is well known, swims along under schools of young fish, 
rising now and then to the surface with great accuracy and securing its prey. 
One can often see them during the summer in the large pool of the station of the 
Fish Commission at Woods Hole, Massachusetts, feeding upon small silversides at 
the surface. 
I have many times in the same way watched young bluefish from the wharf as 
they swim along 3 or 4 feet beneath a school of young fish at the surface, changing 
their position, direction, and their rate constantly, according to the movements of 
their victims above them. At times a continuous stream of schooling silversides 
would pass along the end of the wharf as far as the eye could discern them, while 
just as regularly, though of course in much fewer numbers, one could see a scattered 
column of young bluefish, a few feet beneath, moving in exactly the same manner, 
rising constantly into the mass above, as one might plainly know by the scattering, 
even out into the air, of the invaded minnows. The schools of young herring, men- 
haden, and alewives, are subject to the same foes, and one can imagine that it is in this 
way that the giant squeteague also regulates its feeding times and places to this kind 
of material, preying at once both upon the young herring and their enemies, which 
fall so easily to its strength and swiftness. It is often found also that when the young 
fish are fed upon in abundance by the squeteague, small Crustacea — amphipods, and 
less often small shrimps — and also the green remains of many annelids ( Pliyllodoce ) are 
frequently taken with them. These organisms also swarm in shallower areas frequented 
by young fish, for these latter prey upon the smaller Crustacea, larvae, and copepods, 
while some of the larger kinds of the Crustacea are consumed by the squeteague directly. 
Hot only are young fish used by the squeteague, but the adults of the same 
species, and one can see by reference to the table before given that the columns 
devoted to adult menhaden and herring have a good representation, especially the 
latter. So well adapted for its predaceous life is the squeteague that it swallows a 
large thick menhaden more than half its own length, while the full-grown herring 
figures very commonly in the same way as food. 
The food of the squeteague ( Cynoscion regale) may be characterized perhaps most 
clearly by a concrete instance: On the morning of July 23 there was taken a large 
specimen whose stomach contained an adult herring, in the stomach of the herring 
were found two young scup (besides many small Crustacea), and in the stomach of one 
of these young scup were found copepods, while in the alimentary tract of these last 
one could identify one or two of the diatoms and an infusorian test among the mass 
of triturated material which formed its food. This is an instance of the universal 
rule of this kind of food; the squeteague captures the butter-fish or squid, which in 
turn have fed on young fish, which in their turn have fed upon the more minute 
Crustacea, which finally utilize a microscopic food supply. And the food of the 
squeteague must be regarded as a complex of all these factors, a resultant of several 
life-histories to the given environment. Moreover, circumstances arising to modify 
any of the separate factors cause correlative changes throughout the whole series. 
F. 0. B. 1895—23 
