Trying to Save Redband Trout While Agency Discretion Runs Amok
by Deb Hiller
Redband trout © www.fisheyeguyphotography.com
Snake River Basin (SRB) redband trout are native to the high desert country of southern Idaho, northern Nevada, and eastern Oregon. This species is uniquely adapted to survive the harsh temperature extremes and reduced water flows of the high desert which are lethal to most other trout. SRB redband are an important element of the high desert ecosystem. They are the only native salmonid left in these drainages, and are a significant part of the food chain. Redband eat insects and other fish. They in turn are a food source for dippers, king fishers, mink, otters, and great blue herons.
SRB redband trout are also an evolutionary unique genetic resource which could be important to the survival of Snake River steelhead, as well as isolated resident redband populations now also imperiled. Historically SRB redband interbred with the recently listed anadromous Snake River steelhead and produced anadromous fors of SRB redband trout. However, the construction of the Hells Canyon dam complex in the 1960s blocked anadromous fish passage. Consequently Snake River steelhead continue to migrate to and from the ocean, while SRB redband trout reside their entire life inland in the Bruneau, Owhyee, Boise, and other Snake river tributaries. Whereas much of the native anadromous Snake River steelhead, gene pool has been lost to interbreeding with hatchery fish, the native gene pool of the SRB redband trout is still intact. Thus, where native gene pools of SRB redband trout have the ability to produce anadromous forms (were it not for the Hells Canyon Dam complex), SRB redband trout have the potential to provide the genetic diversity necessary for anadromous Snake River steelhead species survival.
Redband, like other species of trout, are found mainly in streams with riparian vegetation and in-stream cover, including undercut banks, large woody debris, and overhanging vegetation. Streamside vegetation should shade at least 75% of the stream surface during the hours of 11:00am to 4:00pm from June to September. Such vegetation provides both shade that maintains the lover water temperatures required by trout during hot, dry summer months, and habitat for insects which redband feed upon. Redband also occupy lower gradient streams and should have access to pools which provide rearing habitat, resting places, overwintering areas, and refuges from floods, drought, and extreme temperatures. (more…)
