Local interests had requested reinforcing dikes and dams in the Toledo and Pooles Slough areas, as well as work in the Mill Four district and Boones and Nutes Sloughs. While the Pooles Slough and Toledo area work was rejected, in the name of flood control work on the Mill Four...
Maps from the report, "Modeling sea level rise impacts to Oregon’s tidal wetlands : Maps and prioritization tools to help plan for habitat conservation into the future."
Maps from the report, "Modeling sea level rise impacts to Oregon’s tidal wetlands : Maps and prioritization tools to help plan for habitat conservation into the future."
The mouth of the Columbia River (MCR) has a longstanding reputation of hazardous navigational conditions. This reputation has been developing since the first ship, the Columbia, traversed through the inlet in 1792. The hazardous conditions are related to the large waves and strong tidal currents that are common in the...
Tiller Reservoir
In an average year the reservoir is capable of holding
water temperatures in South Umpqua River below 70° F.
for a wide range of regulation schedules. In a year of
maximum temperature, it will also hold temperatures
below 700 F. but flexibility of operation will be restricted.
Regulations...
In situ salinity, turbidity and temperature were measured at discrete depths and water samples for radioanalysis were simultaneously collected in the Columbia River Estuary using a specially designed instrument package. Particulate radioactivity was concentrated by filtration and the dissolved radioactivity by evaporation or ferric oxide bulk precipitation. Radioanalysis was by...
Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement...
The migrations, distribution, and feeding of American shad, Alosa
sapidissima (Wilson), were studied from February 1980 through January
1981 in the Columbia River Estuary, an important rearing zone for
young-of-the-year shad. Sampling was performed with purse seine,
beach seine, and otter trawl.
Adult shad and large numbers of juveniles from...
"A study of smallmouth bass in the Umpqua River System was initiated in 1987 and continued in 1988. Results of that work were reported in a progress report. The study was continued in 1990 after a one-year lapse. This report summarizes results of the work conducted in 1990. Objectives of...
This investigation is focused on smallmouth bass in the Umpqua River system. This investigation contains methods of fish sampling used and, later, describes which methods were more effective for specific tasks. It includes population size, density/structure, mortality rates, and age/growth data regarding the smallmouth bass. See also: Umpqua River smallmouth...
