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Interior Redband Trout
of the Spokane River Watershed
Overview
The Interior Redband Trout (Oncorhynchus mykiss gairdneri) has been a subject of regional concern for many years, but little is known about its genetic purity, abundance, and habitat requirements and locations. The Spokane County Conservation District (SCCD) has been working with local resource agencies to coordinate information regarding the Interior Redband Trout.
Redband trout populations are declining as the result of years of agriculture, mining, logging, dams, road building, competition and hybridization with other non-native trout. This has prompted fisheries managers to investigate their habitat requirements, identify critical habitat, and develop effective conservation and recovery programs. The U.S. Fish and Wildlife Service and various states throughout the species’ historic range have listed the interior redband trout as a species of special concern. Moreover, the U.S. Forest Service and BLM (Bureau of Land Management) have classified the redband as a “sensitive species”.
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Interior Redband Trout
(Oncorhynchus mykiss gairdneri) |
In order to generate local data, the Washington Department of Fish and Wildlife (WDFW), the Coeur d’ Alene Tribe and a group of advanced local high school students recently conducted DNA studies on suspected populations of redband trout. These studies have provided significant information on the abundance, distribution, and genetic diversity of the local rainbow trout populations within the Spokane River Basin.
physical characteristics
The Interior Redband trout (often referred to as the Columbia River redband trout, Fraser River redband trout, Kamloops trout or steelhead) is a subspecies of the coastal rainbow trout (Onchorhynchus mykiss irideus) that is native to western North America. The species share some common physical traits, but the Interior Redband trout is differentiated by larger spots, more elliptical parr marks, and yellow and orange coloring to the body. Additionally, redband trout have distinctly white-tipped anal, dorsal and pectoral fins.
Additional physiological studies have strongly suggested that the redbands are better adapted to the local adverse environmental conditions. Although redband trout prefer cool, clean, relatively low gradient streams, they are able to withstand a wider temperature variation than other trout.
Historical Range
The historic range of the redband extended from the eastern slope of the Cascade Range south to the Sacramento-San Joaquin basin, east into northwestern Montana, and north into upper north British Columbia, Canada. Today however, this trout is limited to only 54.7% of its historic range, with only 5.3% being occupied with strong populations. Small remnant populations are found throughout the Pacific Northwest in the U.S. and British Columbia. Little is known about exact locations of existing resident interior redband populations. ( View maps of habitat locations)
Species conservation and protection
The conservation and protection of the redband trout can be best achieved through a better understanding of this species, it’s life cycle, and it’s habitat requirements. It will also require a collaborative effort among local agencies and watershed residents.
As studies continue, the information will be used to identify critical redband habitats and prioritize habitat restoration work. Current watershed projects addressing water quality and quantity including the Spokane, Little Spokane, and Hangman (Latah) Creek will provide valuable information about the present conditions of our local waterways and lead to efforts to improve conditions necessary for redband trout survival. Other projects such as the Spokane Subbasin Planning project, and studies conducted by the Coeur d’Alene tribe, local schools, and WDFW, will also provide invaluable data for future restoration and management endeavors.
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