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The population status of the IUCN vulnerable Nubian Ibex Capra nubiana is largely unknown in the Middle East because of difficulties conducting intensive surveys. We tested the utility of camera-trapping at permanent water sites to estimate demographics and population trend of the species in the Dana Biosphere Reserve, Jordan. We also studied the relationship between precipitation and the Normalized Difference Vegetation Index NDVI on water site use by the Nubian Ibex, demographics, and population trend. The Nubian Ibex showed a mean annual productivity of 0.81 neonate/female and an adult female survival of 0.87 which is a lower survival rate than found in other ibex species. The mean potential annual rate of increase of this population (λ=1.14) was similar to those reported from other ibex species and indicated a viable population. The capture rate of camera traps (number of photographed animals/camera day) was found not to be a reliable index to monitor population trends because water site use was related to environmental conditions that could not be standardized or predicted a priori. Quantifying population demographic ratios using camera trapping allowed for monitoring the status of key population parameters and growth potential of Nubian Ibex populations in the Dana Reserve, and likely can be used to monitor population status and facilitate informed management of similar populations in the Middle East. [ABSTRACT FROM AUTHOR]

The effect of predation on ungulate populations remains contentious, despite a lack of evidence showing impacts in arid Southwestern USA populations where low precipitation and frequent drought limit ungulate nutritional condition. These conditions can increase predisposition of prey to mortality, which is prerequisite for predation to be compensatory. Consequently, we tested the effect of predation on adult pronghorn Antilocapra americana (Ord 1815) in two populations in arid New Mexico by modeling transformed annual survival rates as a function of predation rates. For this conservative test, a slope=0 indicates complete compensation, whereas a slope=−1 indicates complete additivity. The corrected slope of mortality potentially attributable to predation was >−0.14, and this result was consistent among individual populations. Thus, predation was primarily compensatory. Primarily compensatory predation was related to the relatively low condition of pronghorn individuals, as predated individuals were all below the mean condition of the population, similar to results seen in previous tests of the compensatory versus additive predation hypothesis in the arid Southwest USA. Conditions that predispose individual ungulates to mortality are present more often than not in arid environments, and thus managers should not assume that predation is limiting, regardless of predation rates. [ABSTRACT FROM AUTHOR]

Understanding factors influencing the timing of den entrance and emergence of black bears (Ursus americanus) provides insight for bear management. We determined den entrance and emergence dates for bears in Rocky Mountain National Park (RMNP) and related these dates to vegetative productivity, weather, habitat, and demographic factors to assess the influence of these factors on denning chronology. Date of den entrance was most strongly influenced by age class, precipitation, and proportion of human-use areas in annual home ranges. Den entrance was typically later for adult bears during wetter years and when annual home ranges contained a greater proportion of humanuse areas. Sex and presence of human-use areas were most strongly related to den emergence. Male bears typically emerged from dens before females, and bears emerged from dens earlier when human-use areas composed a greater proportion of annual home ranges. Collectively, our results suggest that denning behavior of black bears in RMNP was strongly influenced by presence of human-use areas, likely because of foods associated with such areas. Managers of black bears in RMNP can use precipitation to predict relative dates of den entrance, thereby allowing for more efficient strategies to combat potentially negative human—black bear encounters. [ABSTRACT FROM AUTHOR]

Precipitation affects large herbivore performance, but data is often available from only a limited number of weather stations that may not correspond with home ranges. Remotely-sensed estimates could potentially address this by providing estimates of precipitation at any point on the landscape. We tested whether 4-km resolution precipitation estimates derived from the Parameter-elevation Relationships on Independent Slopes Model (PRISM) were related to nutritional condition of 3 species of large herbivores and accurately predicted precipitation as measured at weather stations in arid New Mexico. Canonical correlation analyses indicated that condition of elk, mule deer, and pronghorn was related to both PRISM estimates and actual precipitation, but lactation status always had a stronger effect on condition with the exception of pronghorn. Both PRISM and actual precipitation showed comparable influence of precipitation, and the same general ranking of importance of seasonal precipitation, on condition. PRISM estimates were generally positively related to actual precipitation, but deviance was often high and PRISM tended to underestimate actual precipitation. For our study populations, PRISM provided no advantage over the use of dispersed weather stations for assessing nutritional condition. Performance of PRISM may have been hindered because of lack of spatial autocorrelation in precipitation within our sites. • PRISM estimates and actual precipitation were related to herbivore condition. • Influence of PRISM estimates and actual precipitation on condition was similar. • Lactation status generally affected condition more than precipitation. • PRISM estimates were generally positively correlated with actual precipitation. • PRISM tended to underestimate actual precipitation. [ABSTRACT FROM AUTHOR]