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Year Published: 1994

Essential amino acids in northern bobwhite foods

Frequent population declines, high dietary requirements for protein, and the low quality of proteins in agricultural grains led us to hypothesize that essential amino acid (EAA) deficiencies were common in northern bobwhite (Colinus virginianus) foods. We analyzed amino acid concentrations of 21 northern bobwhite foods and compared them with...

Peoples, A.D.; Lochmiller, R.L.; Leslie, David; Boren, J.C.; Engle, David M.

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Year Published: 1994

Decoy trapping and rocket-netting for northern pintails in spring

Decoy traps and rocket-nets were compared for capturing Northern Pintails (Anas acuta: hereafter pintails) during May 1991 on the Yukon Flats, Alaska. Males were captured at similar rates using both methods (1.38 vs. 1.07 males/trap d, respectively), but baited rocket-nets were more efficient than decoy traps for capturing females (0.52 vs. 0.12...

Grand, James B.; Fondell, Thomas F.

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Year Published: 1994

The role of nutrient reserves for clutch formation by Northern Pintails in Alaska

We analyzed carcass composition of female Northern Pintails (Anas acuta) in Alaska to assess the importance of nutrient reserves for formation of first clutches (n = 85) and renests (n = 39). Habitat (tundra vs. boreal forest), hen age (yearling vs. adult), and year (1990 vs. 1991) did not affect nutrient reserve use. During formation of first...

Esler, Daniel N.; Grand, James B.

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Year Published: 1993

Dynamics and distribution of black abalone populations at San Nicolas Island

Dense populations of black abalones (Haliotis cracherodii Leach) were monitored in permanent intertidal plots at nine sites on San Nicolas Island from 1981 through 1990. Densities were essentially constant at all four sites along the north shore of the island throughout the study period. Densities at five sites along the south shore were more...

Hochberg, F.G.; VanBlaricom, Glenn R.
Dynamics and distribution of black abalone populations at San Nicolas Island; 1993; Article; Conference publication; Third California Islands Symposium: Recent Advances in research on the California Islands; VanBlaricom, Glenn R.

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Year Published: 1993

Toward the simulation of the effects of the Great Lakes on regional climate

This paper describes a set of numerical experiments aimed at evaluating the feasibility of applying a version of the National Center for Atmospheric Research-Pennsylvania State University regional model (MM4) to regional climate simulation over the Great Lakes Basin. The objectives of this initial modeling investigation are 1) to examine whether...

Bates, Gary T.; Giorgi, F.; Hostetler, Steven W.

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Year Published: 1993

Environmental contaminants in bald eagles in the Columbia River Estuary

Eggs, blood, and carcasses of bald eagles (Haliaeetus leucocephalus) and fish were collected and breeding success of eagles was monitored in the Columbia River estuary, 1980-87, to determine if contaminants were having an effect on productivity. High levels of dichloro diphenyl dichloroethylene (DDE), polychlorinated biphenyls (PCB's), and 2,3,7,8...

Anthony, Robert G; Garrett, Monte G.; Schuler, Carol

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Year Published: 1993

Factors influencing depredation of artificial duck nests

Because artificial nests can facilitate controlled experiments of nest success, we used them to assess whether human visitation, nest density, vegetation structure, and proximity to habitat edge could affect depredation of duck nests on Yukon Flats National Wildlife Refuge, Alaska. More (P < 0.01) nests in a plot visited daily (100%) were...

Esler, Daniel N.; Grand, James B.

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Year Published: 1992

Breeding chronology of mottled ducks in a Texas coastal marsh

The relationship between breeding chronology of Mottled Ducks (Anas fulvigula fulvigula) and wetland conditions at San Bernard National Wildlife Refuge was examined over a 3-yr period. Median nest initiation dates varied by as much as 68 d among years. Initiation occurred earlier in 1985 and 1987 versus 1986 (P < 0.05). Nesting initiation was...

Grand, James B.

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Year Published: 1991

Analysis and modeling of long‐term stream temperatures on the Steamboat Creek Basin, Oregon: Implications for land use and fish habitat

Steamboat Creek basin is an important source of timber and provides crucial spawning and rearing habitat for anadromous steelhead trout (Oncorhynchus mykiss). Because stream temperatures are near the upper limit of tolerance for the survival of juvenile steelhead, the possible long‐term effect of clear‐cut logging on stream temperatures was...

Hostetler, Steven W.

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Year Published: 1990

Simulation of lake evaporation with application to modeling lake level variations of Harney‐Malheur Lake, Oregon

A physically based eddy diffusion model for simulating the seasonal variation in lake temperature and evaporation is presented and validated. Because no lake‐specific fitting of the parameters of the model is necessary, the model can be used to simulate evaporation in studies of climate change and lake hydrology in a variety of settings. The eddy...

Hostetler, Steven W.; Bartlein, Patrick J

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Year Published: 1987

Aggressive encounters between tundra swans and greater white-fronted geese during brood rearing

Interspecific aggression in waterfowl (Anatidae) is relatively common (McKinney 1965; Kear 1972; Savard 1982, 1984), but interactions leading to mortality of one of the combatants are rarely-observed in the wild. A recent debate (Livezey and Humphrey 1985a, 1985b; Nuechterlein and Storer 1985a, 1985b; Murray 1985) has centered on the proximate and...

Ely, Craig R.; Budeau, David A.; Swain, Una G.