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Conservation of carnivores involves finding solutions to minimize habitat loss and human-wildlife conflict. Understanding the nature of land-use economics can allow us to mitigate both threats. In the Pantanal, the two main economic activities are cattle ranching and ecotourism, each of which directly and indirectly affect the persistence of jaguars (Panthera onca). To understand how the geography of these economic activities is related to jaguar populations, we developed a jaguar distribution model (JDM), livestock density model, and ecotourism lodge density model for the Pantanal. Due to the recent wildfires within the Pantanal, we also assess the impact of burnt areas that are suitable for jaguars, cattle ranching, and tourism. Our JDM indicate that 64% of the Pantanal holds suitable habitat for jaguars. However, jaguar habitat suitability was positively correlated with ecotourism, but negatively correlated with areas most suitable for intensive cattle-ranching. This demonstrates a biome-wide scenario compatible with jaguar conservation. Of particular concern, recent wildfires overlap most suitable areas for jaguars. If wildfires become increasingly frequent, this would represent a serious threat to jaguars and many other wildlife populations. We emphasize the global importance of the Pantanal wetland ecoregion as a key stronghold for long-term jaguar conservation. [ABSTRACT FROM AUTHOR]

Abstract: Evaluating range‐wide habitat use by a target species requires information on species occurrence over broad geographic regions, a process made difficult by species rarity, large spatiotemporal sampling domains and imperfect detection. We address these challenges in an assessment of habitat use for jaguars (Panthera onca) outside protected areas in Central America. Occurrence records were acquired within 12 putative corridors using interviews with knowledgeable corridor residents. We developed a Bayesian hierarchical occupancy model to gain robust inference, allowing for heterogeneity introduced in the sampling process over space and time, using records of jaguar occurrence prone to false positives and false negatives. Probability of false detection of jaguars increased with the number of interviews conducted per unit (from 5.42% to 7.74% given <4 and ≥4 observers per unit). True probability of detection (p = 0.58) increased with the number of days interviewees spent in a survey unit per year. Failing to account for false positives biased predicted habitat use high (c. 1.8×), especially where occurrence records were sparse. Probability of site use by jaguars increased with greater forest cover, prey richness, and distance from human settlements, and decreased with greater agricultural cover, elevation, and distance from protected areas. Site use probabilities averaged 0.15–0.97 by corridor, providing relatively fine‐scale resolution of predicted jaguar occurrence consistent with known patterns of jaguar gene flow across Central America. Model validation, accounting for both false positives and negatives in the observation process, indicated moderate correspondence between model‐predicted observations and actual observations for withheld data (0.65, 95% CRI 0.59–0.71), with sensitivity and specificity rates of 0.69 (0.61–0.77) and 0.59 (0.50–0.68), respectively. These results demonstrate that reliable predictions can be achieved despite the complexity of large‐scale, interview‐based analyses of species occurrence. Synthesis and applications. Our Bayesian hierarchical occupancy model accommodated heterogeneity caused by typical sampling inequities and idiosyncrasies associated with interview data, yielding robust estimates of jaguar habitat use. Our approach is applicable to any wide‐ranging and readily identifiable species and has particular utility for rare species in human‐dominated landscapes where traditional survey techniques (e.g. camera traps) may be impractical. [ABSTRACT FROM AUTHOR]

Spacing patterns of large carnivores can affect demographic parameters of populations that, in turn, influence effective population size. As a result, better understanding of spatial structure can provide insight into effective conservation strategies. We examined home-range size, spacing characteristics, and changes in land tenure of radiocollared Amur tigers (Panthera tigris altaica) on the Sikhote-Alin Biosphere Zapovednik, Russia, from 1992 to 2006. We predicted that both sexes would maintain spatially exclusive home ranges and that subadult female tigers would tend toward philopatry and males would disperse. Home ranges (95% fixed kernel estimates; mean ± SD) of resident females (n = 20 home ranges of 14 females; 390 ± 136 km²) were significantly (P = 0.003) smaller than those of males (n = 6 home ranges of 5 males; 1,385 ± 539 km²). Geometric mean overlap between adjacent females (0.11 ± 0.11 SD) did not differ from that between adjacent males (0.14 ± 0.12). All radiocollared male cubs dispersed (n = 7), but only 2 of 6 female cubs dispersed from their natal home ranges. When human-caused mortality was low, female tigers survived long enough to divide their home range with their daughters, resulting in smaller home ranges and a higher density of breeding females. All females reproduced in these smaller territories, suggesting that they maintained home ranges that were larger than needed to meet reproductive demands. However, when human-caused mortality was high, females often did not survive long enough to bequeath home ranges to daughters, and population density was apparently maintained well below carrying capacity. The impacts of poaching appear to extend beyond the direct loss of individuals, and therefore reserves must be well protected if they are to serve as source populations for adjacent, unprotected areas of tiger habitat. [ABSTRACT FROM AUTHOR]

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Presents information on a study which examined the habitat use and reproductive ecology of the Ocellated Turkey in Tikal National Park, Guatemala. Study area and methods; Results; Discussion.

Presents information on a study that determined macro-habitat use by female black bears in western Maryland. Field-site description; Methodology of the study.