Whatdo theylook like?Rainbow trout vary greatly inappearance, depending on wherethey are found and their age.Generally, rainbows have smallheads with well-developed teethon the roof of the mouth and noteeth at the base of the tongue.They have an adipose fin, a small,soft, fleshy fin on the back behindthe dorsal fin. There are black spotspresent on the back, sides and fins.The adipose fin also has spots,often forming a black borderaround its edge. Young and dwarfadults have parr marks on theirsides. Their colour is silvery overall,often with an iridescent pink toreddish band along the lateral line.The tail is slightly forked, but moreforked in juveniles. In spawningcondition the red stripe on theirsides becomes more pronouncedand their bodies darken to asmoky-grey hue.

British Columbia’s rainbow troutare descended from two ancientlines, and can be

divided into two types: the coastal rainbow trout and the interior red-band trout. The coastal rainbow is heavilyspotted with irregularly-shapedspots above and below the lateralline; a rose-red lateral line ispresent at some stage of the life-cycle, and parr marks are rounded.In the red-band, the spots arelarger; many individuals haveyellow and orange tints on thebody, a slight cutthroat mark (afaint streak under the lower jaw)and light coloured tips on thedorsal, anal and pelvic fins; theparr marks are more oval thanround.

Where do they live?The native range of the rainbowtrout lies west of the RockyMountains from northwest Mexicoto the Kuskokwim River, Alaska,and the Peace and possibly theAthabasca river east of the Rocky

Rainbow Trout Oncorhynchus mykiss

Other common names:

Kamloops trout, Gerrard trout,silver trout, redband trout and

steelhead (see separate fact sheetfor more information on

steelhead).

Typical range in lengthfor adults: 30 - 75 cmMaximum length: 90 cm

Typical range in weightfor adults: 1 - 7 kgMaximum weight: 9 kg

B.C.

Mountains. In B.C., the nativecoastal type is found throughoutour coastal drainage systems, whilethe native red-band is found in theInterior: in the Columbia basin; theFraser system above Hell’s Gate,and in the headwaters of the Liardand Peace river systems.

The rainbow trout has been widelyintroduced outside its naturalrange and can now be foundacross Canada and all around theworld. The typical hatcheryrainbow in B.C. is a red-band ofPennask Lake origin. In other partsof the world it is often adescendant of a coastal stock.

Rainbows occupy many differenttypes of ecosystems: the largerivers and lakes of lower valleys,the tributary streams and smalllakes found in rolling hills at mid-elevation, and mountain streamsand alpine lakes of the highcountry. Stream-dwelling rainbowtrout are usually found in small tomoderately large, but shallow,rivers with gravel bottoms andpool-riffle habitats. Lake-residentrainbow trout are usually found indeeper, cool lakes with adequateshallows and vegetation for goodfood production. There must be agravelly tributary to the lake withadequate flows for spawning.

What do they eat?Rainbow trout mainly eat leeches,crustaceans, molluscs, and insectssuch as caddis flies and black flies,but they also eat salmon eggswhen available. Most often it isthose rainbow trout that eat fish(piscivorous) or run to the sea(steelhead), that reach a large size.

What is their life cyclelike?Rainbow trout usually spawn forthe first time in their third or fourthyear. In the larger piscivorous fish,maturity is delayed. If food andother factors are suitable, mostmature individuals spawn everyyear. They enter their spawningstreams in the spring to lay theireggs in redds, gravel nests built bythe female. They usually spawn inclean gravel in a riffle at the tail of apool. Eggs hatch into alevins afterfour to seven weeks, depending onwater temperature. It takes three toseven days for the alevins to absorbthe remaining yolk to become fry.Free-swimming fry emerge fromthe gravel during the summer. Thefry of lake-resident spawners maymove into the lake immediately, or,when there is sufficient stream flow,they may spend up to three yearsin the stream to avoid lakepredators.

How are theydoing?As a species, therainbow trout is yellow-listed, which meansthat it is not at risk inBritish Columbia.However, manypopulations havesuffered declines andeven extinction as aresult of habitatdamage or overfishing. Maintenance ofnatural geneticdiversity and the manylife-history forms is aconservation concern.

How you can help:• It is important to obey angling

regulations and habitatprotection bylaws, guidelinesand regulations, since they weredesigned to protect the fish andtheir habitat. You should alsoObserve, Record and Reportviolations of the regulations byphoning 1-800-663-9453.

• Rainbow trout are highlyvulnerable to human activities,which alter stream flow, increasesedimentation, reduce cover orraise water temperature. If youown property bordering a streamor lake, try to protect or planttrees and shrubs beside thewater to provide food and shade,and prevent the banks fromeroding.

• Form a group of water stewardsand volunteer to monitor localwater quality or restore naturalstreamside vegetation.

• Be aware that what you dumpinto your septic tank or roadsidestorm drain may find its way intostreams or lakes. Help keep waterquality high by using detergentsand soaps minimally and do notdump harsh chemicals, such asbleach, paint thinner orantifreeze, into drains.

No kidding!• Some people consider the red-

band trout a different species orsubspecies. Detailed geneticstudies may help to clear up thisquestion.

• The largest rainbow trout evercaught in B.C. weighed almost24 kg and came from Jewel Lake.

Prince Rupert

PrinceGeorge

Dawson Creek

Kamloops

U.S.A.

Nelson

Victoria

Vancouver

N.W.T.

QueenCharlotteCity

Washington Montana

WilliamsLake

Fort St. John

YUKON

ALBERTA.

DistributionMinistry of Fisheries