ABOUT...
ACROSS CANADA
AND...
RESOURCES
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FINFISH SPECIES
BROOK TROUT
Introduction
Brook trout is a freshwater farmed species in Canada. In 2003, 1,198 tonnes of Brook trout were produced in Canada valued at C$12.9 million. Brook trout are raised on a commercial scale in Quebec. Some U-fish operations stock brook trout in Alberta.
Basic description
Note: this image belongs to DFO.
Brook trout,
Salvelinus fontinalis, also known as speckled trout, are among the world's most highly-prized gamefish. The brook trout is one of the most colourful trouts. The back is dark green with pale wavy lines. The sides have a purple sheen with blue-haloed red spots. The lower fins have a black stripe behind a pale leading edge. The pale leading edge is characteristic of the charr species (salvelinus). The flesh is white and it has a mild, delicate and sweet taste.
Background
The brook trout is a native North American fish species and is one of the most popular game fishes in eastern Canada. In Canada, the wild
brook trout is widely distributed throughout the Maritime Provinces, Newfoundland, Labrador, Quebec, the Great Lakes drainage basin in Ontario, north to James and Hudson Bays, and in the Nelson and Hayes River systems in northeastern Manitoba. It has been introduced as a game fish in some other provinces, notably Nova Scotia and Alberta.
Brook trout aquaculture began in Quebec in 1857 mainly for the purpose of restocking freshwater lakes and rivers. Commercial scale Brook trout aquaculture began in Quebec during the 1950s with the development of feed pellets. In 1969, the Province of Quebec legalized public fishing in private ponds stocked with Rainbow and Brown trout created. In 1979, the Ministry of Agriculture and Fisheries and the l’Alimentation du Quebec, implemented financial aid and various support programs. The commercial importance of the aquaculture industry entered a higher level after these developments. The regions of highest productivity are l’Estrie, l’Outaouais, Chaudiere-Appalaches, la Mauricie and the Laurentides.
Production cycle
Like salmon species, brook trout are raised from broodstock in freshwater, land-based hatcheries. It is a cold-water species that prefers clear, cool, well-oxygenated water. .When brook trout fry reach 8-10 cm in length, they are moved to outdoor, grow-out facilities. These can comprise concrete raceways, flow-through Danish ponds, or cages. Individual raceways and ponds are typically two to three metres wide, 12 to 30 m long and 1 to 1.2 m deep. Raceways provide well-oxygenated water and water quality can be improved by increasing flow rates. However, the stock is vulnerable to local water quality, and because fish are cold blooded, water temperatures can influence growth rates.
Fish are grown to marketable size (30-40 cm), usually within 9 months, although some fish are grown on to larger sizes over 20 months, depending on market demand.
The stock is graded, usually four times (at 2-5 g, 10-20 g, 50-60 g and >100 g) in a production cycle (first year), when the density (the number of fish in an enclosed area) needs to be reduced, thus ensuring fast growth, improving feeding management and creating product uniformity. Fish quantity and size sampling allows the farmer to estimate growth rates, feed conversions, production costs, and carrying capacity; all essential considerations for responsible farm management.
Alternative grow-out systems for rainbow trout include cage culture production systems (6 m x 6 m wide and between 4 to 5 m deep) where fish (up to 100,000) are held in floating cages in freshwater. Rainbow trout fry of about 70 g weight can attain 3 kg in less than 18 months.
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