NATUEAL HISTORY OF IMPORTANT FOOD-FISHES. 245 



The blue-fish sometimes make their way up the rivers to a considera- 

 ble distance, the adults, however, apparently never entering- the perfectly 

 fresh water. They are found in the Potomac as far north as Acquia 

 Creek, and also far up the Hudson ; indeed, the young of the year are 

 taken as high as Sing Sing on the Hudson and other tidal rivers, where 

 the water is entirely iiesh. 



As already explained, the relationship of these fish to the other in- 

 habitants of the sea is that of an unmitigated butcher; and it is able to 

 contend successfully with any other species not superior to itself in size. 

 It is not known whether an entire school ever unite in an attack upon 

 a particular object of prey, as is said to be the case with the ferocious 

 fishes of the South American rivers ; should they do so, no animal, how- 

 ever large, could withstand their onslaught. 



They appear to eat anything that swims of suitable size, fish of all 

 kinds, but perhaps more especially the menhaden, which they seem to 

 follow^ along the coast, and which they attack with such ferocity as to 

 drive them on the shore, where they are sometimes piled up in windrows 

 to the depth of a foot or more. 



The amount of food they destroy, even if the whole of it be not actually 

 consumed, is almost incredible. Mr. Westgate (page 33) estimates it 

 at twice the weight of the fish in a day, and this is perhaps quite rea- 

 sonable. Captain Spindel goes so far as to say that it will destroy a 

 thousand fish in a day. This gentleman is also of the opinion that they 

 do much more harm to the fishes of the coast than is caused by the 

 pounds. They will generally swallow a fish of a very large size in pro- 

 portion to their own, sometimes taking it down bodily ; at others, only 

 the posterior half. The peculiar armor of certain fish prevents their 

 being taken entire ; and it is not uncommon to find the head of a seul- 

 pin or other fish, whose body has evidently been cut olf by the blue-fish. 

 In the summer-time the young are quite apt to establish themselves 

 singly in a favorite locality, and, indeed, to accompany the fry of other 

 fishes, usually playing below tkem, and every now and then darting 

 upward and capturing an unlucky individual, while the rest dash 

 away in every direction. In this manner they attend upon the young; 

 mullet, atherinas, &c. They are very fond of squid, which may very 

 frequently be detected in their stomachs. In August, 1870, about 

 Fire Island, Mr. S. J. Smith, found their stomachs filled with marine 

 worms, a species of Meteronerels, which, though usually burrowing in 

 the mud, at that season swims freely toward the surface, in connection 

 with the operation of reproduction. This, like the squid, is a favorite 

 bait for the blue-fish ; and they appear to care for little else w^hen these 

 are to be had. This fact probably explains the reason why, at certain 

 seasons, no matter how abundant the lish may be, they cannot be taken 

 with the draih 



Their influence upon other marine animals is not always injurious. 

 Thus, according to Gaptaiu Atwood, the lobsters have multiplied four- 

 fold in Massachusetts Bay since the blue-fish have appeared there, in 

 consequence of their driving away the mackerel, which were the greatest 

 enemy of the young lobsters. Per contra, however, he remarks that the 

 blue-fish actually destroy great numbers of mackerel of all sizes, and 

 they have almost entirely broken up the mackerel fishery in the vicin- 

 ity of Provincetown, making it necessary for the fishermen to resort 

 to far distant waters, to which blue-fish have not yet penetrated. Ac- 

 cording to Dr. Storer, the mackerel fisheries of Massachusetts Bay have 

 been entirely ruined since 1847. 



The fondness of the blue-fish for squid,' Captain Atwood thinks, has 



