Brook Trout

The brook trout, Salvelinus fontinalis, (sometimes called the eastern brook trout, Adirondack coaster lake trout) is a species of fish in the salmon family of order Salmoniformes. In many parts of its range, it is known as the speckled trout. A potamodromous population in Lake Superior are known as coaster trout or, simply, as coasters. Though commonly called a trout, the brook trout is actually a char, along with lake trout, bull trout, Dolly Varden and the Arctic char.

Habits and range
The brook trout is native to small streams, creeks, lakes, and spring ponds. It is native to a wide area of eastern North America but increasingly confined to higher elevations southward in the Appalachian Mountains to northern Georgia, Canada from the Hudson Bay basin east, the Great Lakes–Saint Lawrence system, and the upper Mississippi River drainage as far west as eastern Iowa.[1]

Description
Coloration: green to brown basic coloration with a distinctive marbled pattern of lighter shades across the flanks and back and extending at least to the dorsal fin, and often to the tail. There is a distinctive sprinkling of red dots, surrounded by blue haloes, along the flank. The belly and lower fins are reddish in color, the latter with white leading edges. Often the belly, particularly of the males, becomes very red or orange when the fish are spawning. The species reaches a maximum recorded length of 86 cm (33 in) and a maximum recorded weight of 9.4 kg (14 lb). It can reach at least seven years of age, with reports of 15-year-old specimens observed in California habitats to which the species has been introduced.

Environmental requirements
The brook trout prefers cool, clear waters of high purity and a narrow PH range in lakes, rivers, and streams, being sensitive to poor oxygenation, pollution, and changes in PH caused by environmental effects such as acid rain. Its diverse diet includes crustaceans, frogs and other amphibians, insects, mollusks, smaller fish, and even small aquatic mammals such as voles, worms and flies . It provides food for seabirds and suffers attack by lampreys. The brook trout is a short-lived species, rarely surviving beyond four or five years in the wild.

Individuals normally spend their entire life in fresh water, but some — colloquially called "salters" or "sea run" — may spend up to three months at sea in the spring, not straying more than a few kilometers from the river mouth. The fish return upstream to spawn in the late summer or autumn. The female constructs a depression in a location in the stream bed, sometimes referred to as a "red", where groundwater percolates upward through the gravel. One or more males approaches the female, fertilizing the eggs as the female expresses them. The eggs are slightly denser than water. The female then buries the eggs in a small gravel mound. The eggs hatch in approximately 100 days.

A population of brook trout native to Lake Superior, which run into inflowing rivers to spawn, are called "coasters". Coasters tend to be larger than most other populations of brook trout, often reaching 2 to 3 kg in size. Many coaster populations have been severely damaged by overfishing and by habitat alterations, especially by the construction of hydro-electric power dams, on their inflowing streams. In Ontario and Michigan, efforts are under way to restore and recover coaster populations.

The brook trout is a popular game fish with anglers, particularly fly fishermen. Today, many anglers practice catch-and-release tactics to preserve remaining brook trout populations, and organizations such as Trout Unlimited have been in the forefront of efforts to institute air and water quality standards sufficient to protect the brook trout. Revenues derived from the sale of fishing licenses have been used to restore many sections of creeks and streams to brook trout habitat. Brook trout are also commercially raised in large numbers for food production, being sold for human consumption in both fresh and smoked forms. Because of its dependence on pure water and a variety of aquatic and insect life forms, the brook trout is also used for scientific experimentation in assessing the effects of pollution.

Partially as a result of its popularity as a game fish, the brook trout has been introduced in some areas to which it was not originally native, and has become established widely throughout the world. In some parts of the world, the brook trout has had a harmful effect on native