A5011451628- Fish Ecology and Management Studies
- Fire effects on ecosystems
- Rangeland and Wildlife Management
- Hydrology and Watershed Management Studies
- Species Distribution and Climate Change
- Avian ecology and behavior
- Fish Biology and Ecology Studies
- Wildlife Ecology and Conservation
- Hydrology and Sediment Transport Processes
- Marine and fisheries research
- Ecology and Vegetation Dynamics Studies
- Soil erosion and sediment transport
- Hydraulic flow and structures
- Parasite Biology and Host Interactions
- Water resources management and optimization
- Coral and Marine Ecosystems Studies
- Animal Ecology and Behavior Studies
- Urban Green Space and Health
- Climate change and permafrost
- Precipitation Measurement and Analysis
- Reproductive biology and impacts on aquatic species
- Flow Measurement and Analysis
- Soil and Environmental Studies
- Cassava research and cyanide
- Water Quality and Resources Studies
United States Geological Survey
2016-2022
Forest and Rangeland Ecosystem Science Center
2019-2022
Oregon State University
1993-2020
Universidad de La Laguna
2015-2019
Loyola Marymount University
2012
Oregon Department of Fish and Wildlife
2009
South Dakota State University
1993
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at center of forest management issues this region. immediate threats to federally listed species include habitat loss competition with barred owls varia), which invaded from eastern North America. We conducted a prospective meta-analysis assess population trends factors affecting those using 26 years survey capture-recapture data 11 study areas across owls' geographic...
Changes in the distribution and abundance of invasive species can have far-reaching ecological consequences. Programs to control invaders are common but gauging effectiveness such programs using carefully controlled, large-scale field experiments is rare, especially at higher trophic levels. Experimental manipulations coupled with long-term demographic monitoring reveal mechanistic underpinnings interspecific competition among apex predators suggest mitigation options for species. We used a...
First posted May 21, 2018 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center U.S. Geological Survey 777 NW 9th St., Suite 400 Corvallis, Oregon 97330 Populations of Northern Spotted Owls (Strix occidentalis caurina; hereinafter referred to as Owl) are declining throughout this subspecies’ geographic range. Evidence indicates that competition with invading populations Barred (S. varia) has contributed significantly those declines. A pilot study in...
Triploid fish theoretically divert energy from sexual development and reproductive behavior into somatic growth. We found lengths, weights, relative weights of triploid rainbow trout Oncorhynchus mykiss to be significantly (P ≤ 0.05) less than those diploid at the age 45 months in three South Dakota ponds. Gonadal females was negligible 1989 1990 reduced males during 1990. Catches were always lower catches fish, suggesting survival. Physiological factors, perhaps environmentally induced, may...
We conducted a range-wide investigation of the dynamics site-level reproductive rate northern spotted owls using survey data from 11 study areas across subspecies geographic range collected during 1993-2018. Our analytical approach accounted for imperfect detection owl pairs and misclassification successful reproduction (i.e., at least one young fledged) contributed further insights into population ecology dynamics. Both nondetection state were important, especially because factors affecting...
Abstract In the Upper Klamath Lake basin of Oregon, we applied member‐vagrant hypothesis to larval lake fishes, documented marsh and hydrographic retention for shortnose suckers Chasmistes brevirostris Lost River Deltistes luxatus , examined effect on shoreline abundance juveniles five species fish in August. Emigration was highest from natal rivers, immigration nonnatal areas downstream lake. facilitated by a wind‐generated gyre advection an eastern boundary current. Marshes other...
First posted April 13, 2017 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center U.S. Geological Survey 777 NW 9th St., Suite 400 Corvallis, Oregon 97330 http://fresc.usgs.gov/ Evidence indicates that competition with invasive barred owls (Strix varia) is causing rapid declines in populations of northern spotted (S. occidentalis caurina), the long-term persistence may be question without management intervention. A pilot study California showed removal...
First posted March 14, 2016 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center U.S. Geological Survey 777 NW 9th St., Suite 400 Corvallis, Oregon 97330 http://fresc.usgs.gov Evidence indicates that competition with newly established barred owls (Strix varia) is causing rapid declines in populations of northern spotted occidentalis caurina), the longterm persistence may be question without management intervention. A pilot study California showed...
First posted July 21, 2020 For additional information, contact: Director, Forest and Rangeland Ecosystem Science CenterU.S. Geological Survey777 NW 9th St., Suite 400Corvallis, Oregon 97330 Strix occidentalis caurina (northern spotted owl; hereinafter referred to as owl) have rapidly declined throughout the subspecies’ geographic range. Competition with invading varia (barred has been identified an immediate cause of those declines. A pilot study in California showed that removal barred owls...
Factors affecting the early life survival of fishes are often difficult to demonstrate because variable immigration and mortality rates coupled with noncontinuous sampling may confound estimates bias inference more numerous smaller individuals. The larval production estimate (LPE) method eliminates these problems by compensating catch data for size- or age-specific growth back-calculating abundance at a predetermined size age. Despite its utility, LPE has not been widely applied in studies...
First posted June 28, 2019 For additional information, contact: Director, Forest and Rangeland Ecosystem Science CenterU.S. Geological Survey777 NW 9th St., Suite 400Corvallis, Oregon 97330 Populations of Northern Spotted Owls (Strix occidentalis caurina; herineafter referred to as Owl) have declined throughout the subspecies’ geographic range. Evidence indicates that competition with invading Barred (S. varia) has contributed significantly those declines. A pilot study in California showed...
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This study had two objectives: (1) to use the results of an individual-based particle-tracking model larval sucker dispersal through Williamson River delta and Upper Klamath Lake, Oregon, interpret field data collected throughout Agency Lakes, (2) investigate retention larvae in system as a function flow, wind, lake elevation. is follow-up work reported Wood others (2014) which hydrodynamic Lake was combined with individual-based, fish entering from spawning areas River. In previous study,...
First posted May 24, 2023 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center777 NW 9th StreetSuite 400Corvallis, OR 97330 The northern spotted owl (Strix occidentalis caurina; hereinafter NSO) was listed as “threatened” under the Endangered Species Act in 1990 population declines have continued since that listing. Given species’ protected status, any proposed activities on Federal lands might impact NSO require consultation with U.S. Fish Wildlife...