Salmon are caught by the rod, and by means of nets, the fishings being regulated by law. There are important fisheries in some European and North American rivers. In Europe the fish is found between the latitudes of forty-five and seventy-five degrees, in North America in corresponding latitudes. The flesh when fresh is of a bright orange color, and is of highest flavor when taken from the sea-feeding fish. In the waters of northwestern America are several salmon belonging to a distinct genus, including the quinnat or king-salmon, blue-back salmon or redfish, silver salmon, dog salmon, and humpback salmon. The quinnat has an average weight of twenty-two pounds, but sometimes reaches one hundred pounds. Both it and the blue-back salmon are caught in immense numbers in the Columbia, Sacramento, and Frazer rivers (especially in spring), and are preserved by canning.
Sardine, or Pilchard (Clupea pilchardus) is an important fish closely related to the herring and sprat. In size it grows from ten to fourteen inches; in color it is bluish-green above, whitish underneath and on its sides. It is entirely marine in habit, and its eggs float on the surface of the sea, unlike those of the herring, which are attached to objects at the bottom. The young, before it has attained maturity, is known as the sardine, and as such forms a valuable fishery; the full-grown pilchard is used as an article of diet as well as for bait. The method of capture is usually by drift-net. It is most abundant off the coasts of Portugal, and in the English Channel and the Mediterranean.
Shad is a migratory fish of great food value. It ascends all of the rivers of the eastern coast of the United States every spring to lay its eggs. It is closely related to the herring, but is much larger, and were it not so full of bones it would stand very near the head of food fishes.
Smelt (Osmerus) is a genus of the Salmon family, characterized by strong fang-like teeth, and by rather large scales, which readily fall off. The form is very trout-like, but rather more slender; the tail is larger in proportion, and more forked. The back is whitish, tinged with green; the upper part of the sides shows bluish tints, the lower part of the sides and the belly are of a bright silvery color. The smelt has a peculiar, cucumber-like smell, and a delicious flavor, on account of which it is highly esteemed for the table.
Sole (Solea) is a fish oval in shape, the outline of the snout being semi-circular, and projecting somewhat beyond the mouth. The Common Sole (S. vulgaris) is a fish of high value in European markets. It lives in European seas from the Mediterranean to the north of Denmark, and is rarely caught on the American side of the Atlantic Ocean, although numerous closely allied kinds abound.
Sword-fish (Xiphiidae) are abundantly represented in tropical and subtropical seas. They are among the largest bony fishes, sometimes measuring twelve to fifteen feet in length. The sword, which may be over three feet long, is formed from a compressed prolongation of the upper jaw, and is often strong enough to stab whales fatally, or less advantageously to pierce the bottom of a ship or the planks of a boat. Sword-fish are said to attack whales and other cetacea, and also boats and canoes, and even large vessels.
Trout, a name applied to various members of the Salmon family. The Common or Brown Trout (Salmo fario) varies greatly in appearance, not only with individuals but at different seasons, and this variability has led some authorities to distinguish a number of subspecies.
At midsummer an adult trout is usually brownish or olive in color, with pure white on the belly and gold on the flanks, while the back varies from olive or pale brown to nearly black. The dorsal fin and sides are spotted with black and often also with scarlet. The scales are circular, thin and minute. When the spawning season begins in autumn all the color disappears and the body becomes slimy to the touch. The head of the male is larger than that of the female, and the lower jaw bears a cartilaginous knob. It feeds on a large variety of food, different kinds appealing in turn. It is by cunning imitations of some prevailing fly that the fisherman makes his most cherished captures.
The artificial hatching of trout is now carried on extensively, and lakes and streams can be stocked or replenished with fish if they are not too polluted.