Life Sciences Commons^™

Winter Waterbird Ecology On The Great Salt Lake, Utah, And Interactions With Commercial Harvest Of Brine Shrimp Cysts, Anthony J. Roberts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interactions among commercial fisheries and birds have been studied in open ocean ecosystems and at aquaculture facilities. On the Great Salt Lake (GSL), Utah, USA, a commercial harvest of brine shrimp (Artemia franciscana) eggs (i.e. cysts) occurs annually during fall and winter. Coinciding with commercial harvest is the use of the GSL by millions of waterbirds which has the potential to result in conflict among industry and birds. The objectives of my research were to examine fall and winter ecology of birds using the GSL and interactions with the brine shrimp cyst harvest. I examined the influence of temperature and …

Ecology Of Coyotes On The Valles Caldera National Preserve, New Mexico: Implications For Elk Calf Recruitment, Suzanne J. Gifford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Valles Caldera National Preserve (VCNP) managers were concerned about low elk recruitment observed at the same time as an apparent increase in sightings of coyotes and observations of coyote predation on elk calves. The goal of this study was to describe coyotes’ ecological interactions with elk, particularly coyote diet and movements on the Valle Grande, a large grassland meadow in the southeastern portion of the VCNP.

We examined coyote diet by quantifying undigested remains of food items in coyote scats (feces). The most frequent taxa were rodents (montane voles and pocket gophers), elk (adult and calf), insects (grasshoppers and beetles), …

Roads And The Reproductive Ecology Of Hesperidanthus Suffrutescens, An Endangered Shrub, Matthew B. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the pollination ecology of the endangered Utah desert shrub, shrubby reed-mustard (Hesperidanthus suffrutescens). We also studied the impacts that dust from unpaved roads has on successful reproduction. In addition, we looked at the relationship between the total number of plants, the spacing of plants, and reproduction. We found that shrubby reed-mustard requires pollinators for successful pollination. Pollinators include many small native bees from the genera Andrena, Dialictus, and Halictus. Additionally, we found that reproduction of shrubby reed-mustard is limited, possibly due to scarcity of these bees. We found that dust from the road …

Ecology Of Isolated Greater Sage-Grouse Populations Inhabiting The Wildcat Knolls And Horn Mountain, Southcentral Utah, Christopher J. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus) currently inhabit about 56% of pre-settlement distribution of potential habitat. In 2005, the Castle Country Adaptive Resources Management Local Working Group (CaCoARM) was formed to address concerns regarding local sage-grouse populations in Carbon and Emery counties. In 2006-2007, CaCoARM identified the Wildcat Knolls and Horn Mountain as areas of special concern for greater sage-grouse conservation. Both sites selected by the group were inhabited by what appeared to be small isolated sage-grouse populations. Factors limiting small isolated greater sage-grouse populations throughout its range are diverse and largely site-specific.

During 2008-2009, I captured, radio-collared, and monitored …

Investigation Of Selected Aspects Of Kokanee (Onchorhynchus Nerka) Ecology In Porcupine Reservoir, Utah, With Management Implications, Paul Joel Janssen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several aspects of kokanee (Onchorhynchus nerka) ecology were studied in the fluctuating, 80ha Porcupine Reservoir, Utah in order to determine optimum management strategies. In 1981, escapement was enumerated and estimates of egg deposition were made. An estimate of the resulting fry recruitment was also attempted and was successful up to the arrival of spring runoff. In 1982, escapement was enumerated and estimates of egg deposition were made, with subsequent estimates of egg deposition and percent survival to the advanced eyed stage. Age and growth rates were determined and survival rates estimated.

Escapement for 1981 and 1982 was 5,463 …

Ecology Of Aroga Websteri Clarke In Curlew Valley, Utah-Idaho, Reed L. Kirkland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ecology, life history, and population dynamics of the sagebrush defoliator, Aroga websteri Clarke, were studied in the field and laboratory. The defoliator has one generation a year at the Curlew Valley site. It overwintered in the egg stage and passed through five larval instars. Ten parasite species attacked the defoliator at the study site. Four species, Orgilus ferus, Phaeogenes sp., Spilochalcis leptis, and Apanteles cacoeciae, contributed over 75 percent of the total incidence of parasitism. Parasitism ranged from 20 to 76 percent in 1971, but only ranged from 6 to 29 percent in 1972. This decrease …