Grande Ronde River (Major Population Group)

The Grande Ronde River Summer Steelhead MPG includes four extant (existing) summer steelhead populations; the Grande Ronde River Lower Mainstem Tributaries, Grande Ronde River Upper Mainstem, Joseph Creek and Wallowa River populations. Populations in the Grande Ronde MPG form a relatively coherent group genetically and the habitats they occupy are diverse. Populations in the Grande Ronde River summer steelhead MPG were listed as ‘threatened’ under the Endangered Species Act (ESA) in 1997 (U.S. Office of the Federal Register 1997). Data is currently collected for population level metrics for the Grande Ronde River Upper Mainstem and Joseph Creek populations. Currently not enough data is collected to make population level estimates for the Wallowa River and Grande Ronde Lower Mainstem Tributaries populations.

Oncorhynchus mykiss