—Fish movement during sampling may negatively bias sample data and population estimates. We evaluated the short-term movements of stream-dwelling salmonids by recapture of marked individuals during day and night snorkeling and backpack electrofishing. Bull trout Salvelinus confluentus and rainbow trout Oncorhynchus mykiss were captured in sufficient numbers to evaluate instream movements and th...

The direct predatory effects of introduced rainbow trout Oncorhynchus mykiss on native longnose dace Rhinichthys cataractae were examined using a series of in-stream enclosures to determine if presence, density, or acclimation period of rainbow trout influenced survival of longnose dace. The number of longnose dace remaining in enclosures over the first 72 hours after rainbow trout introduction...

The incidence of hybridization between coastal cutthroat (Oncorhynchus clarki clarki) and rainbow trout (Oncorhynchus mykiss) varies widely among populations. The breakdown of reproductive isolation is of concern to managers, and raises the question: how have the two species retained their genetic and morphological divergence? Using a combination of mitochondrial DNA and nuclear DNA markers cou...

the objective of this study was to compare growth performance and feed conversion ratios of rainbow trout (oncorhynchus mykiss) and brook trout (salvelinus fontinalis) juveniles in monoculture and duo-culture in freshwater and seawater under aquarium conditions. the fish were about 2-months old hatchery-reared brook and rainbow trout with initial weights of 0.934±0.033 (n=360) and 1.014±0.019 (...

Much has been written about introduced rainbow trout interbreeding and outcompeting native cutthroat trout. However, the specific mechanisms by which rainbow trout and their hybrids outcompete cutthroat trout have not been thoroughly explored, and most of the published data is limited to lotic ecosystems. Samples of Snake River cutthroat trout (Oncorhynchus clarkii bouvieri), the rainbow-cutthr...

Arctic grayling (Thymallus arcticus) are salmonids that have a strict freshwater existence in post-glacial North America. Oil and gas development is associated with production of high volumes of hypersaline water. With planned industrial expansion into northern areas of Canada and the USA that directly overlap grayling habitat, the threat of accidental saline water release poses a significant r...

Hybridization between rainbow trout (Oncorhynchus mykiss (Walbaum, 1792)) and westslope cutthroat trout (Oncorhynchus clarkii lewisi (Girard, 1856)) occurs commonly when rainbow trout are introduced into the range of westslope cutthroat trout. Typically, hybridization ismost common inwarmer, lower elevation habitats, butmuch less common in colder, higher elevation habitats. We assessed the tole...

Multiple Hemoglobin Components in Cutthroat and Rainbow Trout Multiple hemoglobin components in fish is a well-documented phenomenon, with cutthroat trout having twelve (Figure 1a) and rainbow trout having nine (Figure 1b) hemoglobin components (Braman et al.1977). A high-resolution starch gel electrophoresis method was developed to resolve eight negatively charged hemoglobin components from bo...

—Comparisons of strontium:calcium (Sr:Ca) ratios in otolith primordia and freshwater growth regions were used to identify the progeny of steelhead Oncorhynchus mykiss (anadromous rainbow trout) and resident rainbow trout in the Deschutes River, Oregon. We cultured progeny of known adult steelhead and resident rainbow trout to confirm the relationship between Sr:Ca ratios in otolith primordia an...