I measured characteristics of vegetation around middens of the endangered Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) in the Pinaleno Mountains of southeastern Arizona. Midden sites were compared to random sites in both the spruce/fir and transition-zone forests. Foliage volume, canopy closure over plot center, volume of downed logs ≥20 cm in diameter, and density of snags >40 cm in diameter at breast height (dbh) were greater at midden sites and best distinguished midden sites from random sites in both forest types. The mean stand age of midden sites was >230 years in the spruce/fir forest and >200 years in the transition-zone forest. As regeneration of disturbed sites will take long periods of time, management applications to protect the red squirrel must focus on preserving existing habitat by limiting activities that remove large trees, snags, or logs, open the forest canopy, create forest edge, or otherwise disrupt forest integrity.

I quantified several aspects of hibernacula use and estimated home ranges of desert tortoises (Gopherus agassizii) in the San Pedro Valley, Arizona. Tortoises hibernated primarily on steep southerly slopes. Hibernacula included burrows in silt, silt with loose gravel, diatomite and/or diatomaceous marl, and beneath an ash layer, often in conjunction with live vegetation, dead and downed vegetation, and packrat (Neotoma albigula) nests. Male tortoises used longer hibernacula than females (p < 0.02). Female maximum hibernacula temperatures were consistently higher than male maximum hibernacula temperatures, but the difference was not significant (0.05 < p < 0.10). Female minimum hibernacula temperatures were significantly lower than males (p < 0.001) and female hibernacula temperatures fluctuated over a significantly wider temperature range than males (p < 0.01). Hibernacula used by males provided greater thermal buffering than those used by females. Duration of hibernation was positively correlated with shelter length. Home-range estimates did not differ significantly between males and females.

I radio-tagged and followed 5 and 9 male Northern Goshawks (Accipiter gentilis atricapillus) during the breeding seasons of 1991 and 1992, respectively, to evaluate their use of different forest conditions in managed ponderosa pine (Pinus ponderosa) forests. Sufficient data for habitat analyses were collected for 11 birds. Minimum convex polygon home-ranges averaged 1,758 ha (SD = 500 ha, range 896-2528 ha) and harmonic mean home ranges averaged 1,530 ha (SD = 477 ha, range 859-2,321 ha). I compared use (i.e., number of hawk locations) and availability (i.e., % of area of home range) for three different forest conditions (canopy closure, edge, and diversity) generated from LANDSAT data. Most (&ge;6) of the 11 birds used the categories in the three overlays in proportion to their availability. Six of the 11 birds used at least one category on one of the overlays nonrandomly. When the categories of canopy closure were ranked for each bird on the basis of relative preference, these ranks increased with increasing canopy closure.

Contextual fit relationships have been examined in many different man-made environments. To date, however, investigation of contextual fit relationships between manmade structures and natural settings has been minimal. The present research examines contextual fit of residential structures to their forested settings. Structure color contrast to setting was found to be inversely related to both perceived fittingness and aesthetic appeal. A positive relationship between fittingness and aesthetic appeal was uncovered. The bearing that these findings can have on visual quality, preservation of forest setting sense of place, and quality of life, is discussed.

I studied habitat use by 9 radio-collared Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis) during the summers of 1988 and 1989 in the Pinaleno Mountains, Arizona. My 2 study areas represented an Engelmann spruce (Picea engelmannii)/corkbark fir (Abies lasiocarpa) association on High Peak and a Douglas-fir (Pseudotsuga menziesii) association on Merrill Peak. I trapped 9 squirrels in 33,400 trap hours, and calculated the seasonal home range for 4 animals, 2 in each study area. Hidden density was 0.54 and 0.2 middens/ha, respectively, but seasonal home range size (x = 3.62 ha) did not vary between habitats. Squirrel numbers decreased on both study areas between 1988 and 1989. I concluded that preference for habitat characteristics in midden areas explained lower densities in the mixed conifer vegetation. Squirrels fed mainly on cones and mushrooms, depending on season and availability. Mt. Graham red squirrels may breed twice/year.

Water associated with the Central Arizona Project (CAP) and its delivery systems attract wildlife. Crossing structures, alternate water sources, and fences have been built to reduce wildlife mortality associated with canals. Their effectiveness, however, has not been evaluated. I assessed the effectiveness of a woven wire and an electric fence located on the CAP and Tonopah Canals, respectively. The purpose of these fences was to prevent desert mule deer (Odocoileus hemionus crooki) from entering canals. I established track plots to quantify differences in deer use between areas separated by the canals. I used line intercept transects to examine differences in the vegetation between the north and south sides of the CAP. Both types of fences were effective in keeping deer out of the canal. The north side of the CAP had more deer use and more ground cover than the south side. If future offshoot canals are small, they may be left unfenced, if follow-up studies reveal no significant wildlife mortality.

I identified habitat use by 12-18 mountain sheep (Ovis canadensis nelsoni) in a 320-ha enclosure between June 1990 and June 1991 on the Desert National Wildlife Refuge, Nevada. The enclosure included 9 vegetation associations and 5 slope classes. I used a non-mapping technique and line transects to determine availability of vegetation associations and slope classes, and species composition, respectively. I determined use of habitats by mountain sheep with instantaneous sampling. Mountain sheep used midslopes and draw associations on the west side of the study area, and slope classes of 36-80% more than expected based on availability. I tested Hansen's (1980) habitat evaluation model on the study area. The model was >98% accurate in predicting mountain sheep use of habitat. Habitat use by mountain sheep in the enclosure was similar to habitat use of free-ranging mountain sheep.

I monitored female desert mule deer (Odocoileus hemionus crooki) (n = 7) with radio telemetry in the Belmont and Bighorn mountains, Arizona, 1991. I examined habitat use, size of seasonal ranges, predation by coyotes, and behavior, and I identified fawning and fawn rearing habitat. Female desert mule deer preferred the montane vegetation associations and avoided creosote flats (Larrea tridentata) during fawning. Size of seasonal ranges were smaller in the 2 weeks postpartum (X = 3.75 km2 than in the 2 weeks prior to fawning (X = 6.71 km2 Activity during the first or last 4 hours of daylight differed 2 weeks postpartum and the remainder of the year (P = 0.034). Female desert mule deer were less active during daylight 2 weeks postpartum. Females during fawning were not any closer to water than the remainder of the year.

I examined the influence of human disturbance on Coues white-tailed deer (Odocoileus virginianus couesi) by subjecting deer within separate but similar areas to different levels of disturbance during breeding seasons, 1990-91 and 1991-92. Marked does (n=7) were seldom found outside their harmonic mean core areas (χ² = 7.140, 6 df), or harmonic mean home ranges (χ² = 1.030, 6 df). In summer 1992, I collected reproductive information from 10 adult females within each area. Fetal rates within the control and treatment areas were 1.3 fetuses/female and 1.1 fetuses/female, respectively. The corpora albicantia counts, reflecting the 1991 fetal rate, were 0.9 for the control, and 1.1 for the treatment areas. Calculated conception dates within both areas showed a peak in early January and their distributions were not significantly different (P=0.32). There was no difference in reproduction or movement in response to increased disturbance of 60 hunter-days/15km².

Little dietary information exists for northern goshawks (Accipiter gentilis) in the southwestern United States. I conducted 1,539 hours of direct observation at 20 active goshawk nests in ponderosa pine forests on the North Kaibab Ranger District, Arizona, 1990-1992. I recorded 385 prey deliveries at a mean delivery rate of 0.25/hr. I identified 63 deliveries to class, and 307 to genus or species. Golden-mantled ground squirrels (Spermophilus lateralis) and cottontail rabbits (Sylvilagus spp.) were the most common mammalian prey species (41%). Stellar's jays (Cyanocitta stelleri) and northern flickers (Colaptes auratus) were the most common avian prey species (16%). Mammals and birds accounted for 76 and 24% of the prey observed, and mammals accounted for 94% of the biomass used by northern goshawks. I compared the characterization of diet of northern goshawks based on direct observation to the characterization of diet based on prey remains. Diet based on prey remains differed from diet based on direct observation for individual prey species and the proportion of mammals and birds. Goshawk diet information based on prey remains should be interpreted cautiously. (Abstract shortened by UMI.)