Brook Trout, Salvelinus frontinalis
Brook Trout, Salvelinus frontinalis. Fish caught from the Credit River, Caledon, Ontario, Canada, April 2010. Length: 18 cm (7.0 inches). Catch, photograph, and identification courtesy of Kenneth Tse, Toronto, Ontario, Canada.
Brook Trout, Salvelinus frontinalis. Fish caught from a small steam in the greater Toronto area, April 2010. Length: 18 cm (7.0 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.
Brook Trout, Salvelinus frontinalis. Fish caught from a small steam in the greater Toronto area, April 2010. Length: 20 cm (7.9 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
Brook Trout, Salvelinus frontinalis. Fish caught from Spencer Creek, Keno, Oregon, April 2015. Length: 20 cm (7.9 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
Brook Trout, Salvelinus frontinalis. Fish caught from a small steam in the greater Bishop, California area, April 2010. Length: 22 cm (8.7 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
Brook Trout, Salvelinus frontinalis, is a member of the Salmon and Trout or Salmonidae Family, and is also known as the Brook Char, Brookies, Eastern Brook Trout, Mud Trout, Specked Trout and Squaretail and in Mexico as trucha de arroyo. Globally, there are seventeen species in the genus Salvelinus, of which only this species is found in Mexico’s freshwater systems. The Brook Trout is the state fish of nine states in the United States and is the Provincial Fish of Nova Scotia.
The Brook Trout has a fusiform body with a prominent adipose fin. They are an overall dark green to brown color, with a distinctive marbled pattern of lighter shades across the flanks and back. They have a distinctive sprinkling of red dots, surrounded by blue halos along the flanks. Their 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. Their anal fin has 3 or 4 spines and 8 to 14 rays; their caudal fin is straight; their dorsal fin has 3 or 4 spines and 8 to 14 rays.
The Brook Trout is a freshwater species found in cold, clear, unpolluted, well oxygenated small streams, beaver ponds, rivers and lakes with stable temperatures and vegetation. They are found in water temperatures between 1oC (34oF) and 18oC (65oF) and at depths up to 6 m (20 feet). They reach a maximum of 86 cm (2 feet 10 inches) in length and 8.0 kg (17 lbs 10 oz) in weight. In general, fish found in brooks and streams are smaller than those found in ponds and lakes. As of January 1, 2024, the International Game Fish Association world record for length stood at 43 cm (17 inches) with the fish caught in Yellow Creek, Woodbury, Pennsylvania in September 2021. The corresponding world record for weight stood at 6.6 kg (14 lbs 8 oz) with the fish caught in the Nipigon River in Ontario, Canada in 1915. They are active daytime feeders that consume a wide variety of organisms including amphibians, crustaceans, fishes, aquatic and terrestrial insects, leeches, small mammals, mollusks, and worms. Brook trout normally mature in two years but may spawn after one year. Brook Trout are migratory making late fall runs to the headwaters of streams for spawning. Spawning occurs at water temperatures of between 4°C (40°F) and 10°C (50°F). The female excavates a shallow hole over a groundwater upwelling or the tail of a pool, in gravel. The male fertilizes the eggs as they are deposited, and the female follows and covers the eggs with gravel. Eggs may be deposited by one pair of trout over a series of small nests. The eggs overwinter in the gravel and hatch in the spring. Newly hatched fry remain in the gravel until their yolk sac is absorbed and move to shallow areas of the stream, with low water speeds, taking shelter in submerged aquatic vegetation or near the shoreline. They are known to hybridize with the Artic Char, Salvelinus alpinus, the Brown Trout, Salmo trutta, and Lake Trout, Salvelinus namaycush. They have life spans of up to twenty-four years.
The Brook Trout is a native to Eastern North America in the United States and Canada, but has been introduced throughout North America and in other countries. They have been transported to new locations for centuries via wagon, mule, ship and train to new locations. They were introduced to Mexico in 1947 in several streams near El Zarco, Guanajuato and Mexico City, providing a product of high economic and nutritional value with local employment opportunities within rural communities. They adapted quickly at elevations about 1,830 m (6,000 feet).
The Brook Trout is a straight forward identification that cannot be confused with any other species. They can coexist with both Brown and Rainbow Trout but can also be replaced by them.
From a conservation perspective the Brook Trout has not been formally evaluated. They are heavily pursued by recreational anglers and in many regions, they are heavily regulated. In many locations their native populations have been significantly reduced by human developments, acid rain, and the introductions of Brown Trout and Rainbow Trout. They are now confined to remote locations at higher elevations. In other areas they are considered to be a pest with reported adverse ecological impacts after introductions. They are a major focus of recreational anglers and fly fishermen and conservation groups trying to restore and return them to their native locations. The Brook Trout is raised by aquaculture for food, being less popular than Rainbow Trout due to their slow growth rates, and for the stocking of private streams and ponds. They are utilized by the aquarium trade on a limited basis. They are also utilized to assess the water quality of contaminated and polluted water bodies.