We explored potential negative effects of exotic brown trout (Salmo trutta) on native sculpin (Cottus sp.) on the Logan River, Utah, USA by (i) examining factors most strongly correlated with sculpin abundance (e.g., abiotic conditions or piscivory?), (ii) contrasting the extent of brown trout predation on sculpin with that by native cutthroat trout (Oncorhynchus clarkii utah) and (iii) estimat...

Rainbow trout native to the McCloud River, California, USA (Oncorhynchus mykiss stonei) are thought to represent a relic, nonanadromous trout adapted to harsh, fragmented environments. These fish, commonly named McCloud River 'redband' trout, survive in their most primitive form in a small, spring-fed stream, Sheepheaven Creek, in the upper McCloud River drainage. Turn-of-the-century fisheries ...

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...

in the present study storms of the economic, political, and human dimensions of space (with the help of satellite imagery (modis, after a time, and the destructive power of hurricanes, including discussions of the factors influencing the formation dynamics, thermodynamics and environmental issues, snow storm 2005 investigated. for a more detailed analysis of synoptic snow storm of guilan, rasht...

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...

BACKGROUND Estimates of fishing and natural mortality are important for understanding, and ultimately managing, commercial and recreational fisheries. High reward tags with fixed station acoustic telemetry provides a promising approach to monitoring mortality rates in large lake recreational fisheries. Kootenay Lake is a large lake which supports an important recreational fishery for large Bull...

—Cutthroat trout Oncorhynchus clarkii frequently are displaced by nonnative brook trout Salvelinus fontinalis, but the ecological mechanisms of displacement are not understood. Competition for food and predation between greenback cutthroat trout O. c. stomias and brook trout were investigated in montane streams of Colorado. A replicated field study was used to describe the population density, d...

1. The effects of diet composition and insulin treatment on blood glucose level, blood amino acid concentrations, the activities of two hepatic gluconeogenic enzymes (fructose diphosphatase, EC 3.1 .3.11; phosphoenolpyruvate carboxykinase, EC 4 .1 . 1 .32) and of two hepatic glycolytic enzymes (hexokinase, EC 2 .7 .1 . 1 ; pyruvate kinase, EC 2 . 7 . 1 .40) were examined in rainbow trout (Sulmo...

--In the southern Appalachian Mountains, native brook trout Salvelinus fontinalis and introduced rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta are at the southern extremes of their distributions, an often overlooked kind of marginal habitat. At a regional scale composed of the states of Virginia and North Carolina, species were found to be distributed along latitudinal and elev...

Portable antennas have become an increasingly common technique for tracking fish marked with passive integrated transponder (PIT) tags. We used logistic regression to evaluate how species, fish length, and physical habitat characteristics influence portable antenna detection efficiency in stream-dwelling brown trout (Salmo trutta), bull trout (Salvelinus confluentus), and redband trout (Oncorhy...