58 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



fish 8.7 to 9.2 inches long, nor in a female 10.5 inches. The smallest 

 ripe female which he found was 11.5 inches, and the smallest ripe 

 male 11.8 inches. 



^^I. Food.— The mackerel, as stated above, is a surface feeder 

 and lives exclusively upon free-swimming organisms. These organ- 

 isms are of two different kinds, each of which it captures in a different 

 way. 



The young mackerel and the mackerel of the early spring schools 

 feed upon all sorts of minute surface creatures, such as small Crustacea, 

 larval invertebrates, etc. These it captures in the same way as the 

 menhaden, by swimming open-mouthed through the water and 

 straining the sea-water through its gill rakers. This includes what 

 is known to the fishermen as " redseed." 



During the latter part of the summer, however, and until the 

 autumn migration away from the coasts, small fishes and the young 

 of other species become plentiful, and the mackerel then feeds chiefly 

 on these. These they hunt by sight, and capture them chiefly by 

 darting at them individually.* The most important of these fishes 

 are, perhaps, the sand launce, anchovies, silversides, young hake, 

 smelt, and young herring and menhaden. 



VII. Enemies. — According to Goode, the gannet is perhaps the 

 most destructive enemy of the mackerel. Porpoises and whales also 

 feed on mackerel schools. Their worst enemies among the " finny 

 tribes " are the mackerel shark and dogfish. In shallow water, also, 

 squid feed on the young mackerel, in the capture of which they show 

 a considerable degree of ingenious strategy by changing their color 

 until it so perfectly resembles that of the sand that they are invisible. 



THE CHUB MACKEREL OR THDIBLE-EYE. 



(Scomber colias.) 



PLATE IV. 



The ChulD [Mackerel is of very wide distribution and occurs in the 

 Atlantic and Pacific oceans, north to England, Maine, and San 



