Treesearch

We summarized existing knowledge regarding the distribution and status of bull trout Salvelinus confluentus across 4,462 subwatersheds of the interior Columbia River basin in Oregon, Washington. Idaho, Montana, and Nevada and of the Klamath River basin in Oregon, a region that represents about 20% of the species' global range. We used classification trees and the patterns of association between known distributions and landscape characteristics to predict the likely distribution of bull trout in unsampled subwatersheds. Bull trout are more likely to occur and the populations are more likely...

The Aquatics and Riparian Science Teams analyzed the seven alternatives by evaluating their effectiveness in sustaining aquatic ecosystem structure and function, and their expected effect on 25 taxa of native fishes. Our analysis focused on alternatives as defined in Chapter 3 of the Preliminary Draft Environmental Impact Statements (EISs) (USDA and USDI 1996a, 1996b). The analysis consisted of three steps. In step one, we identified the level of protection, maintenance, or restoration of aquatic and riparian habitats offered by each alternative. In step two, we identified expected changes...

We summarized presence, absence, current status, and potential historical distribution of seven native salmonid taxa - bull trout Salvelinus confluentus, Yellowstone cutthroat trout Oncorhynchus clarki bouvieri, westslope cutthroat trout O. c. lewisi, redband trout and steelhead O. mykiss gairdneri, stream type (age-1 migrant) chinook salmon O. tshawytscha. and ocean type (age-0 migrant) chinook salmon - in the interior Columbia River basin and portions of the Klamath River and Great basins. Potential historical range was defined as the likely distribution in the study area prior to...

Underwater observations were used to describe habitat use and diel behavior of juvenile bull trout (Salvelinus confluentus) at the onset of winter (0.8°C) in a second-order central Idaho stream. All fish observed during daytime counts were concealed beneath "home stones" (mean dimensions 32.3 by 21.9 cm) in primarily pool and run habitats. Focal point depths and velocities averaged 57.2 cm and 4.7 cm/s (home stone removed). Fish maintained stations over substrate with low percentages of fine (< 2 mm, mean= 5.2%) sediment. Concealed bull trout were not evenly distributed across the stream...

In this chapter, we report on a broad-scale scientific assessment of aquatic resources conducted as part of the Interior Columbia Basin Ecosystem Management Project. Our assessment area, collectively referred to as the Basin, includes the Columbia River Basin east of the crest of the Cascade Mountains (Washington, Oregon, Idaho, western Montana, and small portions of Nevada, Utah, and Wyoming), and those portions of the Klamath Basin and the Great Basin in Oregon.

It is commonly recognized that aspen (Populus tremuloides) ecosystems in the Interior West provide numerous benefits: (1) forage for livestock, (2) habitat for wildlife, (3) water for downstream users, (4) esthetics, (5) sites for recreational opportunities, (6) wood fiber, and (7) landscape diversity. Loss or potential loss of aspen on these lands can be attributed primarily to the successional process, reduction (or elimination) of fire, and long-term overuse by ungulates. Western aspen forests are unique because they reproduce primarily by suckering from the parent root system.

Western aspen forests are unique because they reproduce primarily by suckering from the parent root system. Generally a disturbance or die back is necessary to stimulate regeneration of the stands. Unlike other tree species, if aspen stands are lost from the landscape, generally they will not return through natural processes. If current conditions continue (e.g., lack of fire, wildlife use, grazing by livestock) that have prevailed for the past 1 00 to 140 years, most aspen stands will eventually be replaced by conifers, sagebrush, or possibly tall shrub communities.

In the Interior west, if current conditions continue (e.g., lack of fire, wildlife use, grazing by livestock, natural succession) that have prevailed for the past 100 to 140 years, most aspen stands will eventually be replaced by conifers, sagebrush, or possibly tall shrub communities. Current estimates are there has beeh a 60% decrease in aspen dominated lands since the arrival of European man. This decrease is persistent across the entire state of Utah and probably holds true for most of the Interior West. This loss of aspen from the landscape translates to a loss of water, forage, and...

Thirty-four Populus biotechnology chapters, written by 85 authors, are comprised in 5 sections: 1) in vitro culture (micropropagation, somatic embryogenesis, protoplasts, somaclonal variation, and germplasm preservation); 2) transformation and foreign gene expression; 3) molecular biology (molecular/genetic characterization); 4) biotic and abiotic resistance (disease, insect, and pollution); and 5) biotechnological applications (wood properties, flowering, phytoremediation, breeding, commercialization, economics, and bioethics).

Native plants are generally considered the best option for plant materials to restore productivity and diversity to degraded rangelands (McArthur 1988). It is difficult to find native plants capable of becoming established from seed in dense stands of introduced annual species such as cheatgrass. It has been easier to import species such as crested wheatgrass to restore perennial grasses on degraded rangelands. Although successful, such revegetation has not been without drawbacks. Establishment of large areas of a single plant species lowers vegetative diversity and may be aesthetically...