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The efficacy of providing water sources in desert ecosystems to enhance wildlife populations and their distribution continues to be debated among wildlife managers. Some argue wildlife water developments provide a direct benefit to numerous species, while others point to the potential that wildlife water developments alter competition or predation dynamics and disrupt native communities. Additionally, some have argued that the availability of water may become more important to wildlife in the face of vegetative changes associated with expansive fire and conversion of shrub or forest lands to grasslands which alters the thermal landscape available to animals. I evaluated the influence of free water and expansive fire on aspects of the ecology (habitat selection, space use and survival) of Gambel's quail (Callipepla gambelii) in the Mojave Desert of southwestern Washington County, Utah, USA. I attached radio-transmitters to a total of 206 quail (74 adult males, 67 adult females, and 65 juvenile males and females) and monitored them from 2010 – 2013. For chapter one of my thesis, I evaluated the response of marked quail to removal of access to water in a before-after controlled impact (BACI) design. I found little influence of water removal on survival as models with this effect received little to no support and overlap in confidence intervals occurred between treatment and reference groups. Likewise, the distance from the center of the summer home range to the nearest water source did not differ by year (F = 1.63; P = 0.19) or treatment (removal of water) (F = 0.89; P = 0.35) and pairwise comparisons of distances for the treatment by year interaction were not significant (P > 0.05 in all cases). For size of home range area, however, I found strong effects for year (F = 3.07; P = 0.03), treatment (F = 4.67; P = 0.03), and their interaction (F = 7.61; P = 0.01). Mean home range size for quail was 6.10 and 1.63 km2 for animals in the reference area during treatment years (2012 and 2013) compared to 5.07 and 8.99 km2 for quail in the treatment area during 2012 and 2013, respectively. Removal of water influenced size of summer home ranges, but not the location of the summer home range or survival rates. I hypothesize that removal of access to free water required quail in the treatment area to expand their space use patterns in 2013 in order to satisfy water demands via pre-formed water. For chapter two of my thesis, I evaluated habitat selection of Gambel's quail in relation to vegetation type, topographic features, water, and recent (4-7 years) expansive fire. Gambel's quail selected areas of decreased roughness which were closer to water and fire boundaries than random locations. I found that quail preferred moderate (< 10 degrees) hillsides and ravine bottoms. I found no evidence that quail avoided the burned areas within their home ranges and 80% of their telemetry points were <500 meters from a burn edge. The Beaver Dam slope topography strongly influenced habitat selection for Gambel's quail and they showed strong selection for water sources during summer months. These data also suggest that wildfires have had limited impact on habitat selection by this species, four to seven years later.

This work is a quantitative description of the renal excretion and the post-renal modification of ureteral urine from native (unanesthetized, uninfused, and normal hydropenic) desert quail, Lophortyx gambelii. The technique used in this study establishes the glomerular filtration rate (GFR), urine flow rate, and urinary excretion of water, sodium, potassium, and uric acid for desert quail in a relatively undisturbed state and in steady-state balance with regard to intake and output of water, sodium, and potassium. In contrast, conventional methods of determining GFR in birds include the use of anesthesia, cloacal or ureteral canulation, and infusion of fluids to introduce filtration markers (e.g. inulin) and to cause a diuresis (e.g. by using mannitol). In the present study, native desert quail had a urine flow rate of about 40 g/kg.day compared to over 500 g/kg.day for desert quail previously studied using conventional methods. Also in the present study, GFR was about 1.6 ml/kg.min which is about 25% lower than previously reported (2.1 ml/kg.min) for desert quail studied with conventional techniques. Renal absorption of the filtered loads of water, sodium and potassium also was determined in the present study. The fractions of the filtered loads reabsorbed by the renal tubules were: for water 98%, for sodium 99.4%, and for potassium 42%. These findings illustrate that renal reabsorption of these filtered substances is less complete in birds than in mammals where, in man for example, about 99% of the water and 99.8% of the sodium are normally reabsorbed. In addition, this study evaluates the role of the cloaca and lower intestines in changing the composition of the ureteral urine. Ureteral urine is modified in the cloaca and lower intestines of the desert quail before being excreted with the final droppings. This modification results in reabsorption of about 70% of the water and sodium and about 80% of the potassium in the ureteral urine. Thus for the desert quail, post-renal reabsorption of water and sodium from ureteral urine produced by the kidneys increases the total amounts of the filtered loads reabsorbed to 99% for water and 99.7% for sodium, which are nearly the same as seen for man. It is concluded that post-renal reabsorption of water and sodium is an important aspect of fluid and electrolyte balance in native desert quail. About 65% of the uric acid present in the ureteral urine was found to be degraded during its passage into the lower intestines. This is particularly significant because trapping of sodium and potassium occurs within the uric acid precipitates which form in bird urine. It was determined that about 20% of the sodium and 33% of the potassium in the ureteral urine are trapped within uric acid precipitates. Degradation of uric acid may increase the reabsorbable pools of these cations and facilitate their reabsorption by the tissues of the lower intestines. Since the intestinal ceca of birds contain large populations of uric acid-decomposing bacteria, and because other studies have suggested large amounts of water are reabsorbed in the ceca of birds, the role of the ceca in post-renal modification of urine was evaluated. The results are not conclusive. Cecaectomized (Cx) birds showed only a transitory increase in water loss when compared to sham operated (Sh) birds. No difference in uric acid excretion was seen between Cx or Sh birds. Thus, no obligatory role for the ceca in post-renal reabsorption of water and electrolytes, or in degradation of uric acid, was evident.

No description available.

In this study, we evaluated the development of stress response in (1) two different species of quail, one species that is relatively fast-growing (Japanese quail, Coturnix japonica) and one that is relatively slow-growing (Gambel’s quail, Callipepla gambelii) and (2) two strains of a single species, the Japanese quail (wild-type and domesticated), that differ considerably in final size. Our data indicate that wild-type Japanese quail and Gambel’s quail have experienced trade-offs between growth and the stress response (e.g. Gambel’s quail have slower growth rates, but greater levels of CORT). However, the domesticated strain of Japanese quail used in this study seem to violate some predictions based on the life history theory (e.g. the domestic strain has faster growth rates and greater levels of CORT). The data in this study contribute to the understanding of differences in the stress response between species that exhibit different life history strategies.