Thesis (M.S.)--Boise State University, 2009. / Title from t.p. of PDF file (viewed Feb. 23, 2010). Includes abstract. Includes bibliographical references.

Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 16, 2008). Includes bibliographical references (p. 52-55).

Thesis (M.S.)--Boise State University, 2009. / Includes abstract. Includes bibliographical references.

Thesis (M.A.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 638-651).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1950. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [452]-463).

No description available.

Various physical and biological factors affecting annual productivity in a Red-tailed Hawk population in north-central Oregon were investigated. The percentage of the population successfully fledging one or more young was the most important factor in determining the number of young fledged per pair in a given year. Neither clutch size nor the number of young fledged per successful nest varied significantly. Percent pair success was correlated with several January weather variables. A cold and dry January is positively correlated with Red-tailed Hawk productivity. This is apparently related to the onset of rapid vegetative growth and this in turn is positively correlated with the timing of the emergence and reproductive cycle of the principal prey, Belding’s and Townsend's ground squirrels, (Turner 1972). Because a cold and dry January delays the emergence of ground squirrels, the period of emergence and dispersal of the young squirrels more closely corresponds to the time of peak food needs of the young Red-tailed Hawks, and greater pair success is observed. This relative abundance of prey appears to be of greater importance than actual abundance. Red-tailed Hawk productivity was found to correlate significantly with two habitat variables & the presence of adequate numbers of dispersed hunting perches and relative ground squirrel abundance. The presence of one or more perches per sixteenth section provided the best single correlation. Neither territory size nor competition from interspecifically territorial Swainson's Hawks were correlated with productivity of Red-tailed Hawk territories. Red-tailed Hawks with inhabited dwellings within their territories fledged significantly more young than those without.

Preference is an important element in economic analysis, but usually regarded an inborn and exogenous characteristic. By the concept of natural selection, evolutionary game theory can explain lots of animal characteristics, including humans. With this idea, this paper extends the classical Hawk-Dove game to a two-period-life model, in which fights can cause deaths. We derive the population dynamics and the evolutiona-rily stable strategy. The competitive attitude and patience are determined by resource value and cost. And under a given common patience level, the evolutionarily stable strategy is a mixed strategy. But if the ¡§announcement effect,¡¨ an extra benefit from showing the winning record, is large enough, all-hawk may be the equilibrium. In ad-dition, under variable patient levels, the model can determine the equilibrium patience, and numerical simulation shows that dove-strategy accompanies a higher patient level than hawk.

Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains xii, 73 p. : ill. (some col.), map (some col.). Vita. Includes abstract. Includes bibliographical references.

In the Canadian prairies, native grasslands have been largely replaced by an agricultural landscape with a mosaic of habitats now better described as aspen parkland. Although habitat requirements of true prairie Buteo species, Swainson's (Buteo swainsoni) and ferruginous hawks (B. regalis), are relatively well identified, little is known about habitat use by red-tailed hawks (B. jamaicensis ) in this ecoregion. This study, evaluating productivity and habitat selection of red-tailed hawks breeding in aspen parkland, was conducted on Prairie Habitat Joint Venture (PHJV) assessment sites in central Saskatchewan in 1997 and 1998. Red-tailed hawk nesting densities and productivity were determined at three sites. Home ranges were mapped. Macrohabitat use and availability data were generated from digitized aerial photographs of PHJV assessment sites using a Geographic Information system. Microhabitat variables were measured in 0.04 ha plots centered on nests and random locations. (Abstract shortened by UMI.)