Mining impacts on stream systems have historically been studied over small spatial scales, yet
investigations over large areas may be useful for characterizing mining as a regional source of stress to
stream fishes. The associations between co-occurring stream fish assemblages and densities of various
“classes” of mining occurring in the...
Headwater streams and wetlands are integral components of watersheds that are critical for biodiversity, fisheries, ecosystem functions, natural resource-based economies, and human society and culture. These and other ecosystem services provided by intact and clean headwater streams and wetlands are critical for a sustainable future. Loss of legal protections for...
We assessed the parasitism of Metaparasitylenchus hypothenemi on its host, the
coffee berry borer, in 20 coffee plantations of Mexico. A total of 23,568 adult
borers were dissected, with 179 of these infected with nematodes (0.76% infection
rate). Although the level of parasitism is not encouraging, the nematode is another...
Hatchery supplementation of anadromous salmon is extensive across the Pacific Northwest region with millions of juvenile salmon stocked annually. The influence of hatchery-origin fish as prey items in recipient ecosystems has been explored, but influences of these fish on broader stream nutrient dynamics has not been well-studied. Salmon-derived nutrients (SDN)...
Direct behavioral observations of multiple free-ranging animals over long periods of time and large geographic areas is prohibitively difficult. However, recent improvements in technology, such as Global Positioning System (GPS) collars equipped with motion-sensitive activity monitors, create the potential to remotely monitor animal behavior. Accelerometer-equipped activity monitors quantify animal motion...
The most active phenolics in Quercus sideroxyla Humb. & Bonpl. residual bark were identified and evaluated following a chromatographic fractionation. Bark powder was defatted with hexane and crude extract (CE) was obtained by extraction with aqueous acetone (70%). A liquid partition with ethyl acetate was performed to produce an organic...
Cobb hotspot, currently located beneath Axial seamount on the Juan de Fuca ridge, has the temporal
but not the isotopic characteristics usually attributed to a mantle plume. The earlier volcanic products of
the hotspot, from eight volcanoes in the Cobb-Eickelberg seamount (CES) chain, show a westward age
progression away from...
Dual-axis accelerometer global positioning system collars can be used to remotely record the activity level and behavior of free-ranging animals, but inter- and intraspecific variations in motion among behaviors necessitate calibration for each species of interest. To date, little work has been done to determine the best duration for sampling...
Annual grass invasion into shrub-dominated ecosystems is associated with changes in nutrient cycling that may alter nitrogen (N) limitation and retention. Carbon (C) applications that reduce plant-available N have been suggested to give native perennial vegetation a competitive advantage over exotic annual grasses, but plant community and N retention responses...
Understanding local and geographic factors influencing species distributions is a prerequisite for conservation planning. Our objective in this study was to model local and geographic variability in elevations occupied by native and nonnative trout in the northwestern Great Basin, USA. To this end, we analyzed a large existing data set...