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Distribution of introduced
trout and char species
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| Salmo trutta (Linnaeus) | |
| Salmo=Latin for the Salmon
of the Atlantic; "to leap" trutta=trout |
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Original introductions of Brown Trout in Canada
came to Newfoundland in 1884 from Loch Leven, Scotland. The European
Brown Trout inhabits lakes streams and coastal rivers and has a
reputation as a wily game fish with experienced anglers. The Brown
Trout was originally introduced to British Columbia from eggs purchased
from Wisconsin and Montana in 1932 (Clemens and Wilby 1946). These
eggs were hatched in a hatchery, and the fry were deposited in several
rivers on Vancouver Island. Many sea-run populations of Brown Trout
are currently established and promoted as exotic angling opportunities.
Brown Trout were introduced into the Columbia Basin via the Kettle River system in 1957, and they are occasionally taken by anglers in the West Kettle and Similkameen rivers.
Brown Trout can be identified by the presence of large, dark brown or black spots along the lateral surfaces, surrounded by pigmented halos of blue and red colouration. Unlike other members of the genus Salmo, Brown Trout spawn in the fall and early winter. The gape of the maxillary extends past the margin of the eye and the caudal fin is almost square or slightly forked.
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| Salvelinus fontinalis (Mitchill) | |
| Salvelinus=an old name for Char fontinalis=living in springs |
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Brook Trout are native to northeastern North America where they are a common game fish inhabiting both lakes and streams. Most Brook Trout populations presently found in British Columbia originated from numerous transplants from eastern Canada early in the 20th C. Brook Trout are one of the most commonly transplanted salmonid species in Canada; they do not require running water to spawn, and transplants are equally successful in lakes and in rivers. Members of the genus Salvelinus are prone to hybridization within and outside their genus (e.g. Baxter et al. 1997; Crossman and Buss 1966). There is some concern that the introduction of the non-native Brook Trout has had deleterious effects on native fluvial and lacustrine Bull Trout (Salvelinus confluentus) as well as Kokanee (Oncorhynchus nerka) populations throughout B.C.
G.C. Carl reported seeing Brook Trout in 1944 in a small stream north of Keremeos, and populations are currently established throughout the Columbia system except the Flathead River. Brook Trout can be identified by the presence of distinct, black streaks on their dorsal fin, truncate caudal fin, vermiculations (wormlike patterns) on their dorsal surface, and green and red spots on the lateral surfaces surrounded by blue halos.
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| Salvelinus namaycush (Walbaum) | |
| Salvelinus=an old name for
Char namaycush=a First Nations' name meaning deep dweller |
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Lake Trout are a large cold-water char that frequent
deep lakes. They are one of the larger members of the genus Salvelinus,
and grow up to 45 kg. The native distribution of Lake Trout includes
most of northern North America including British Columbia north
of Shuswap Lake (Lindsey 1964). Although not native to the Columbia
Basin, Lake Trout were successfully introduced into the lower Columbia,
lower Kootenay and Okanagan systems for purposes of large game angling.
The introduction of these large piscivorus fish has had a deleterious
effect on some Bull Trout (Salvelinus confluentus) populations
to the point that some populations are now extinct (Donald 1993).
Lake Trout are fall spawners and -- unlike most salmonids -- do not require running water for the development of their eggs. Most spawning occurs along shallow gravel margins of lakes, although some stream spawning has been reported.
Lake Trout can be identified by their large mouth that extends past the margin of the eye, the presence of creamy irregular spots and vermiculations (wormy markings) covering the fins and dark body and a deeply forked caudal fin.
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| Thymallus arcticus (Pallas) | |
| Thymallus=ancient name referring
to the odour of thyme arcticus=of northern distribution |
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Arctic Grayling are common in lakes and fast-flowing
streams in the Mackenzie drainage of northern B.C., and less common
in the extreme southeastern portion of the province in the Flathead
River system. Naturally occurring pockets of Arctic Grayling survived
Pleistocene Glaciation in Montana and Michigan, but these natural
populations have become extinct since the 1930s (Carl et al.
1967). Arctic Grayling have since been re-introduced into western
Montana, and it is thought that the Flathead River populations originated
from this introduction.
Arctic Grayling typically follow a contagious distribution and are seldom found alone. They inhabit pools in larger rivers, and make seasonal foraging and reproductive migrations in and out of lakes and small tributaries.
Arctic Grayling are easily identified by their brilliant iridescent lateral surface colouration and prominent sail-like dorsal fin. Juvenile Arctic Grayling are easily confused with juvenile whitefish of the genus Prosopium, but Prosopium's jaws have poorly developed teeth in comparison to the young Arctic Grayling.
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| Coregonus clupeaformis (Mitchill) | |
| Coregonus=angle-eyed clupeaformis=herring-shaped |
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Lake Whitefish are widely distributed though out Canada where they are recognized as a valuable commercial species (Scott and Crossman 1973). Lake Whitefish are generally restricted to the cool bottom regions of larger lakes where they feed primarily on benthic insects and crustaceans. This species is of particular scientific interest as, like many Coregonids, Lake Whitefish are highly polymorphic, and many lakes contain two forms. The "dwarf" and "normal" forms differ in growth rate, size of maturity, gill raker number and exhibit distinct genetic differences (Bodaly 1979; Bernatchez and Dodson 1991). Although Lake Whitefish are native to northern British Columbia, populations from eastern Canada were introduced to the larger lakes of the Columbia Basin in hopes that they would become a commercially viable species. The introduced populations have become neither abundant nor sizable, and the species is caught only occasionally by anglers today. An attempt to develop a commercial fishery in Okanagan Lake in 1929 was considered unsuccessful. Transplanted Lake Whitefish are currently distributed in the Arrow and Kootenay lakes as well as the Okanagan system.
Lake Whitefish are a large-scaled species with a silvery, flat-sided, deep body. The snout overhangs the lower jaw and the brow is commonly concave.
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BC Museum |
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