Onchoryncus mykiss

Status

Introduced to the north-eastern portion of the Avalon Peninsula from California in 1887. They currently occupy the Avalon Peninsula, with populations occurring as far west as Clarenville.

Habitat

Prefer more open and fast water compared to Brook Trout, and can tolerate temperatures between 0 to 25^oC. Adults in lakes prefer 18^oC. Their preferred lake depth depends on oxygen levels and temperature.

Food

Plankton, crustaceans, insects, snails, leeches, fish and fish eggs.

Appearance

Highly variable in colour: steel blue, yellow-green or brown above, silver to pale yellow-green below; pink to red stripe on sides (except in sea run form).

Breeding Biology

Unlike other trout found in Newfoundland, rainbows spawn in the spring. Preferred spawning sites are fine gravel beds in riffles above pools. Females dig redds, or pits, while attended by several males, but one male is usually dominant. Egg development depends on local conditions, but eggs will usually hatch in seven to eight weeks, and require an additional three to seven to absorb the yolk sacs before becoming free swimming.