Juvenile Chinook Salmon (Oncorhynchus tshawytscha) leave the natal reach at different times and move downstream at different rates which can increase their productivity by allowing them to utilize habitats on different temporal scales and spreading risk of localized stochastic events. This life history diversity can also allow fish to adapt...
Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations...
The typical coho salmon life history has been characterized by juvenile fish that spend their entire first year in freshwater habitats before migrating into estuaries as smolts. However, reports of early migrating coho fry (age 0), including migration downstream to estuarine habitats, date back to the 1960s. Until a few...
:
_____________________________________________________________________
GuillermoR. Giannico
The typical coho salmon life history has been characterized by
In the fall through spring of 2002/03 and 2003/04, the composition of fish and amphibian communities were examined in intermittent streams in the upper Willamette river basin in western Oregon. I recorded standard aquatic habitat variables and water nutrient concentrations (nitrate and phosphate) and correlated them with fish and amphibian...
Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but appears to be quite small. Limited spawning and rearing habitats, combined with the effects of introduced species and other anthropogenic changes...
The overall goal of this study was to identify multiple scales of habitat use and habitat electivity by redband/steelhead trout and define the limiting factors affecting the distribution patterns of this species during summer flows.
The main objective in chapter 2 was to identify the most important habitat associations that...
Stream restoration efforts have increasingly started to focus on management actions that restore ecological function rather than focusing on species-specific habitat needs. Restoration practitioners in the Pacific Northwest have implemented numerous large-scale floodplain restoration projects to restore stream function at the valley scale. Some of these projects attempt to restore...
Migration and spawning phenology of Pacific Salmon is linked to the hydroregime, and thought to be triggered by increases in river discharge and decreases in water temperature. However, little data exists that describes direct fine-scale linkages between the hydroregime and spawning in Coho Salmon. This study evaluated the spatial and...
Juvenile salmonids display highly variable spatial and temporal movement patterns that are influenced by density dependent (e.g., competition, predation) and density independent (e.g., genetics, stream discharge, physical habitat conditions) factors. The effects of these factors differ with fish life history stage, but will ultimately affect how salmonids utilize freshwater nursery...
Tidal marshlands in the upper estuary ecotone provide essential habitat for
juvenile salmonids. In this environment, salmonids grow rapidly and acclimate to
saltwater. Worldwide, tidal marshes have been diked and drained to provide
agricultural and residential land. Tide gates are one-way doors integrated into
dike systems that prevent saltwater flooding...