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As a corollary to a more comprehensive study on their ecology, we documented blood and urinary profiles for 10 free-ranging desert mule deer (Odocoileus hemionus crooki) (five males, five females) captured by net-gun shot from a helicopter during February 1988 in Saguaro National Monument, Arizona. Pursuit with the helicopter for netting deer ranged from 3 to 15 min. Blood profiles included seven hematological characteristics and 12 serum chemistries, electrolytes, hormones and enzymes. Urine samples were assayed for urea nitrogen, creatinine, sodium, potassium, calcium and phosphorus. Urinary data were compared as ratios to creatinine. Serum cholesterol was greater (P less than 0.05) in males than females. Pursuit time was correlated with serum non-esterified fatty acids (r = 0.67, P less than 0.05) and influenced urinary specific gravity (r2 = 0.77, P less than 0.004), urea nitrogen: creatinine (r2 = 0.79, P less than 0.005), and potassium: creatinine (r2 = 0.42, P = 0.08) ratios. Increasing specific gravity was related to urinary creatinine concentration (r2 = 0.72, P less than 0.008). All deer exhibited acute adrenal stimulation, accompanied by elevated serum creatine phosphokinase and urinary potassium: creatinine ratios, which were indicative of acute excitement and muscle trauma associated with the capture process. We demonstrated that urinary data are a valuable supplement to serum data in demonstrating effects of intense physical exertion, and both forms of data emphasize the need to assess capture-related excitability as a source of variation in blood and urine characteristics of free-ranging desert mule deer.

In January 1993 we simulated a conductive hearing loss in three Mexican bighorn sheep (Ovis canadensis mexicana) by placing bone wax or saline solution in their ear canals. Our objective was to test whether lesions of the external auditory canal caused by psoroptic mites (Psoroptes ovis) may lead to conductive hearing loss in bighorn sheep. We assessed the effects of these manipulations using the auditory brainstem response test. Placing saline solution in the external auditory canal, which loads the tympanic membrane, had a more dramatic effect on the auditory brainstem response than did bone wax. We propose that decreased hearing sensitivity or alterations in resonance characteristics of the external auditory canal, due to psoroptic scabies lesions, may make bighorn sheep more susceptible to predation.

The Central Arizona Project (CAP) is one of the largest water delivery systems in the western United States. The CAP is a series of open canals that divert Colorado River water east to Phoenix, then south through Tucson, Arizona. Centra Arizona Project canals dissected over 250 km of desert mule deer (Odocoileus hemionus crooki) habitat. The canals are an attractive nuisance to deer. We documented deer mortality during 1979 to 1989 along 179 km of the CAP (formerly called the Granite Reef Aqueduct but renamed in 1989 as the Hay den-Rhodes Aqueduct [HRA]). Deer were entrapped in the canal during the construction years (1979–1987) or drowned when water was added in 1987; however, mortality was minimized when fencing was constructed. Deer managers and biologists should be aware of the effects of creating attractive nuisances in desert mule deer habitat and of the costs associated with minimizing mortality.

We studied the diets of desert mule deer (Odocoileus hemionus crooki Mearns) at 3 sites in Arizona and collated this information with that of previous diet studies of desert mule deer across their range in the United States. We documented 96 browse, 69 forbs, 14 succulent, and 6 grass species that each constituted greater than or equal to 1% of the diet during greater or equal to 1 season. The occurrence of individual plant species varied spatially and temporally. Changes in nutrient levels and climatic influence on relative availability and phenology of plant species likely influenced diet. Desert mule deer rely heavily on browse and forbes, which make up the majority of their diet (> 90%). Grasses and succulents were generally < 5% of the diet. Rangeland managers should strive to keep desert rangelands productive with a diversity of forage so animals have opportunities to exercise free choice of diet.

use of forage classes. Diets range from consisting primarily of graminoids (Barrett, 1964; Dominguez, 1976) to those dominated by browse and forbs (Krausman et al., 1989). The digestive anatomy plays a critical role in establishing constraints on herbivore diet composition (Hanley, 1982) and is an important determinant of ecological niche (Bell, 1971; Janis, 1976). Ruminoreticular (RR) volume relative to body size is considered important in relation to the ability to digest graminoid species in other than succulent condition (Hanley, 1982). Within ruminants, species that selectively feed primarily on forbs and succulent vegetation tend to have smaller digestive capacities than roughage grazers (Hofmann, 1973). Graminoid species contain considerable amounts of cellulose as a structural

We captured 10 free-ranging desert mule deer (Odocoileus hemionus crooki) (five males and five females) by net-gun from a helicopter and immobilized them with xylazine hydrochloride (HCl) (100 mg) and ketamine HCl (300 to 400 mg) injected intramuscularly. Arousal and ambulation times were 13.9 +/- 4.2 and 14.3 +/- 4.2 min in eight deer injected intravenously with tolazoline HCl (3.0 mg/kg). We observed a curvilinear relationship (R = 0.50, P less than 0.01) between rectal temperature and time after induction of anesthesia. Mean peak temperature (41.4 C) occurred at 23.7 +/- 3.2 min postinduction and was greater (P less than 0.01) than the mean temperature measured initially (40.8 C). Heart and respiratory rates (108 beats/min and 75 breaths/min) were elevated prior to immobilization. Mean heart rate increased (P less than 0.05) from 90 +/- 9 beats/min in anesthetized deer to 120 +/- 13 beats/min after tolazoline HCl injection. A 20% capture-related mortality rate suggests this combination of physical and chemical capture has serious limitations. Captive deer permitted to recover from xylazine HCl-ketamine HCl immobilization without a reversal agent were able to walk in 290 +/- 79 min.

Identification des differences entre l'habitat couramment utilise par Ovis canadensis mexicana (44 Km 2 dans les Santa Catalina Mountains) et l'habitat historique maintenant abandonne (206 Km 2 ).La structure de la vegetation et les risques de perturbation humaines sont les 2 principaux parametres pris en compte