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Year Published: 2005

First record of the plains minnow, Hybognathus placitus, in Canada

Seven Plains Minnows, Hybognathus placitus, Family Cyprinidae, were collected on 11 June 2003 from Morgan Creek, in Grasslands National Park, Saskatchewan, Canada. This collection is the first record of the species in Canada and extends the northern distribution limit of the species. Of 95 Hybognathus spp. collected at the site,...

Sylvester, R. M.; Freeling, S. E.; Berry, C. R.

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Year Published: 2005

How much is enough? The recurrent problem of setting measurable objectives in conservation

International agreements, environmental laws, resource management agencies, and environmental nongovernmental organizations all establish objectives that define what they hope to accomplish. Unfortunately, quantitative objectives in conservation are typically set without consistency and scientific rigor. As a result, conservationists are failing...

Tear, Timothy; Kareiva, Peter; Angermeier, Paul; Comer, P.; Czech, Brian; Kautz, R.; Landon, L.; Mehlman, D.; Murphy, K.; Ruckelshaus, M.; Scott, J. Michael; Wilhere, G.

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Year Published: 2005

Survival and selection of migrating salmon from capture-recapture models with individual traits

Capture–recapture studies are powerful tools for studying animal population dynamics, providing information on population abundance, survival rates, population growth rates, and selection for phenotypic traits. In these studies, the probability of observing a tagged individual reflects both the probability of the individual surviving to the time...

Zabel, Richard; Wagner, Tyler; Congleton, James; Smith, Steven G.; Williams, John G.

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Year Published: 2005

p,p'-DDE depresses the immune competence of chinook salmon (Oncorhynchus tshawytscha) leukocytes

p,p′-DDE, the main metabolite of DDT, is still detected in aquatic environments throughout the world. Here, the effects and mechanisms by which p,p′-DDE exposure might affect the immune system of chinook salmon (Oncorhynchus tshawytscha) was studied. Isolated salmon splenic and pronephric leukocytes were incubated with different...

Misumi, Ichiro; Vella, Anthony T.; Leong, Jo-Ann C.; Nakanishi, Teruyuki; Schreck, Carl B.

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Year Published: 2004

An annotated bibliography of selected guides for stream habitat improvement in the Pacific Northwest

This annotated bibliography is a response to widespread interest in stream habitat improvement in the Pacific Northwest by land managers, governmental and nongovernmental organizations, and the lay public. Several guides to stream habitat improvement have been written in the past, but may not be easily accessible to people from diverse backgrounds...

Keim, R.F.; Price, A.B.; Hardin, T. S.; Skaugset, Arne E.; Bateman, D.S.; Gresswell, R.E.; Tesch, S. D.

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Year Published: 2004

Differential consumption of eastern red cedar (Juniperus virginiana) by avian and mammalian guilds: Implications for tree invasion

Increased abundance and distribution of eastern redcedar (Juniperns virginiannus), a native species in the Great Plains, has been associated with changes in ecosystem functioning and landscape cover. Knowledge of the main consumers and dispersal agents of eastern red cedar cones is essential to understanding the invasive spread of the species. We...

Horncastle, V.J.; Hellgren, E.C.; Mayer, P.M.; Engle, David M.; Leslie, D.M.

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Year Published: 2003

A comparison of visual prey detection among species of piscivorous salmonids: Effects of light and low turbidities

Differences in reaction distance to prey fish by piscivorous salmonids can alter predator–prey interactions under different visual conditions. We compared reaction distances of three piscivorous salmonids commonly found in western lakes: cutthroat trout, Oncorhynchus clarki utah, rainbow trout, O. mykiss, and the nonnative lake char,...

Mazur, Michael M.; Beauchamp, David A.

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Year Published: 2002

Does food availability affect energy expenditure rates of nesting seabirds? A supplemental-feeding experiment with Black-Legged Kittiwakes (Rissa tridactyla)

We used a supplemental-feeding experiment, the doubly labeled water technique, and a model-selection approach based upon the Akaike Information Criterion to examine effects of food availability on energy expenditure rates of Black-legged Kittiwakes (Rissa tridactyla) raising young. Energy expenditure rates of supplementally fed females (n = 14)...

Jodice, Patrick G.R.; Roby, Daniel D.; Hatch, Scott A.; Gill, Verena A.; Lanctot, Richard B.; Visser, G. Henk

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Year Published: 2002

Feeding habits of the endangered Ozark big-eared bat (Corynorhinus townsendii ingens) relative to prey abundance

Feeding habits of the endangered Ozark big-cared bat (Corynorhinus townsendii ingens) in eastern Oklahoma, USA, were studied from July 1987 through July 1988. Diets were determined from microscopic analysis of fecal pellets and compared with arthropods collected in Malaise traps. Although lepidopterans comprised only 21.5% of the available prey,...

Leslie, David M.; Clark, B.S.
Feeding habits of the endangered Ozark big-eared bat (Corynorhinus townsendii ingens) relative to prey abundance; 2002; Article; Journal; Acta Chiropterologica; Leslie, David, M. , D. M.; Clark, B. S.

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Year Published: 2002

Food limitation and the recovery of sea otters following the 'Exxon Valdez' oil spill

We examined the potential role of food limitation in constraining the recovery of sea otters Enhydra lutris in Prince William Sound, Alaska, following the 'Exxon Valdez' oil spill. The spill resulted in the removal of a large number of sea otters in 1989, and as of 1998, the portion of the population in the heavily oiled northern Knight Island...

Dean, Thomas A.; Bodkin, James L.; Fukuyama, Allan K.; Jewett, Stephen C.; Monson, Daniel H.; O'Clair, Charles E.; VanBlaricom, Glenn R.

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Year Published: 2002

Major areas of ground-water development; Escalante Valley, Beryl-Enterprise area

No abstract available. 

Christiansen, H.K.; Burden, Carole B.

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Year Published: 2001

Carbon balance of the terrestrial biosphere in the twentieth century: analyses of CO2, climate and land use effects with four process-based ecosystem models

The concurrent effects of increasing atmospheric CO2 concentration, climate variability, and cropland establishment and abandonment on terrestrial carbon storage between 1920 and 1992 were assessed using a standard simulation protocol with four process-based terrestrial biosphere models. Over the long-term(1920–1992), the simulations yielded a...

McGuire, A.D.; Sitch, S.; Clein, Joy S.; Dargaville, R.; Esser, G.; Foley, J.; Heimann, Martin; Joos, F.; Kaplan, J.; Kicklighter, D. W.; Meier, R.A.; Melillo, J.M.; Moore, B.; Prentice, I.C.; Ramankutty, N.; Reichenau, T.; Schloss, A.; Tian, H.; Williams, L.J.; Wittenberg, U.
Carbon balance of the terrestrial biosphere in the twentieth century: analyses of CO2, climate and land use effects with four process-based ecosystem models; 2001; Article; Journal; Global Biogeochemical Cycles; McGuire, A.D.; Sitch, S.; Clein, J.S.; Dargaville, R.; Esser, G.; Foley, J.; Heimann, M.; Joos, F.; Kaplan, J.; Kicklighter, D.W.; Meier, R.A.; Melillo, J.M.; Moore, B., III; Prentice, I.C.; Ramankutty, N.; Reichenau, T.; Schloss, A.; Tian, H.; Williams, L.J.; Wittenberg, U.