Brook trout
The brook trout, also known as the aurora trout, is a striking freshwater fish belonging to the Salmonidae family. Recognizable by its vibrant coloration, it features bright-red spots bordered by blue on its sides, dark wavy lines along its back, and pink or reddish hues on its lower fins. Adult brook trout typically weigh around five pounds and can range in length from ten to twenty-five inches, although larger specimens have been recorded. They spawn in the fall, with females constructing nests, or redds, in specific environments depending on whether they inhabit streams or lakes. Brook trout require cold water to thrive, ideally between 57.2 to 60.8 degrees Fahrenheit, and are particularly sensitive to higher temperatures. While they are a popular target for anglers across New England, their populations are considered to be of least concern. The average lifespan of brook trout ranges from six to eight years, making them a significant species in recreational fishing.
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Brook trout
The brook trout is described as a beautiful fish with red spots and rings of blue on its sides. It has long been a favorite catch among fishers.
Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Salmoniformes
Family: Salmonidae
Genus: Salvelinus
Species: Fontinalis
The brook trout, also called the aurora trout, is a striking fish. Its sides are speckled with bright-red spots with blue borders. Along its back, dark, wavy lines are present. These lines also appear on the dorsal fin. The lower fins, the pelvic and anal fins, are pink or reddish with traces of white along the outer edges. During spawning, or when the female lays her eggs and the male then fertilizes them, the male's belly becomes orange, while his lower sides tun black.
The body of the brook trout is approximately five times as long as it is deep. The caudal, or tail, fin has only a slight fork to it and is the reason the brook trout is often referred to as a squaretail. The fins are soft-rayed, which means each fin is made up of a series of individual sections called rays. The average weight of the adult brook trout is about five pounds (about two kilograms). The average length is ten to twenty-five inches (twenty-five and a half to sixty-three and a half centimeters). One brook trout, however, was caught which weighed fourteen and a half pounds (six and a half kilograms) and measured a length of thirty-one and a half inches (eighty centimeters). A brook trout of this size is not common.
Brook trout spawn from September in the northern sections of their range to early December in the southernmost sections. The number of eggs a female produces depends on her size. A six-inch (fifteen centimeter) female may produce 100 eggs, while a fourteen-inch (thirty-five centimeter) female is capable of producing up to 1,200 eggs. In the gravel, the female brook trout constructs a redd, or spawning bed where she lays her eggs, in the fall.
The female which spawns in the stream is very particular about where she lays her eggs. She seeks out cold, spring-fed water. The female which inhabits the lake is not as selective as her stream-dwelling relative. She spawns over bark, twigs, and other assorted materials near the shoreline but also lays her eggs in deeper water.
The incubation period, or amount of time it takes for eggs to hatch, is affected by the water temperature. At a temperature of thirty-five degrees Fahrenheit (about two degrees Celsius) the incubation period is 144 days. At fifty-five degrees Fahrenheit (thirteen degrees Celsius) it is thirty-five days. The exact length of the incubation periods for a given fish is difficult to determine, as the temperature of the water is always changing. There is a great likelihood that a large number of eggs are lost in water temperatures below thirty-nine degrees Fahrenheit (about two degrees Celsius).
People have successfully introduced other species of trout, like the brown trout and rainbow trout, to many different parts of the world. This has not been the case with the brook trout. Brook trout cannot survive in water warmer than seventy-seven degrees Fahrenheit (twenty-five degrees Celsius). They require cooler waters than most other species of trout. The ideal water temperature for the brook trout is 57.2 to 60.8 degrees Fahrenheit (about fourteen to sixteen degrees Celsius).
Today, some of the largest brook trout are found in Labrador, northern Quebec, and northern Manitoba in Canada. Sea-run trout, those which migrate from saltwater to freshwater, are rarely as large as those which remain in one area year-round. The brook trout continues to be a popular game fish in lakes and streams throughout New England in the United States. Their population status is listed as least concern.
The average lifespan of the brook trout is six to eight years.
Bibliography
Roberts, James. “Salvelinus fontinalis.” Animal Diversity Web, 2000, animaldiversity.org/accounts/Salvelinus‗fontinalis/. Accessed 1 Apr. 2024.
Hitchcock, Kristin. “Brook Trout.” A-Z Animals, 27 Sep. 2022, a-z-animals.com/animals/brook-trout/. Accessed 1 Apr. 2024.