Broad scale population estimates of declining species are desired for conservation efforts. However, for many secretive species including large carnivores, such estimates are often difficult. Based on published density estimates obtained through camera trapping, presence/absence data, and globally available predictive variables derived from satellite imagery, we modelled density and occurrence of a large carnivore, the jaguar, across the species’ entire range. We then combined these models in a hierarchical framework to estimate the total population. Our models indicate that potential jaguar density is best predicted by measures of primary productivity, with the highest densities in the most productive tropical habitats and a clear declining gradient with distance from the equator. Jaguar distribution, in contrast, is determined by the combined effects of human impacts and environmental factors: probability of jaguar occurrence increased with forest cover, mean temperature, and annual precipitation and declined with increases in human foot print index and human density. Probability of occurrence was also significantly higher for protected areas than outside of them. We estimated the world’s jaguar population at 173,000 (95% CI: 138,000–208,000) individuals, mostly concentrated in the Amazon Basin; elsewhere, populations tend to be small and fragmented. The high number of jaguars results from the large total area still occupied (almost 9 million km2) and low human densities (< 1 person/km2) coinciding with high primary productivity in the core area of jaguar range. Our results show the importance of protected areas for jaguar persistence. We conclude that combining modelling of density and distribution can reveal ecological patterns and processes at global scales, can provide robust estimates for use in species assessments, and can guide broad-scale conservation actions.

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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.

The jaguar Panthera onca is threatened throughout its range and categorized as Near Threatened on the IUCN Red List. To inform conservation of the jaguar population in Corcovado National Park, Costa Rica, population size was estimated using data from a 3-month camera trap study. Individuals were identified from their coat patterns. The resulting density estimate of 6.98 ± SD 2.36 individuals per 100 km2 was lower than expected. The sex ratio was 1.33 males per female, and the minimum home ranges of two males were 25.64 and 6.57 km2. Hunting pressure on jaguar and white-lipped peccaries Tayassu pecari, the jaguar's main prey in the Park, may be responsible for the low jaguar density as space does not seem to be a limiting factor. The numbers of females may have been underestimated because of sampling bias and therefore the sex ratio obtained in this and similar studies must be interpreted cautiously. Better protection of the corridor that connects the Park with other protected areas is essential to guarantee long-term survival of the jaguar in Costa Rica.

Jaguar (Panthera onca) predation of green turtles (Chelonia mydas mydas) is now a common occurrence in Tortuguero National Park, Costa Rica. The abundance of green turtles during nesting season ensures a constant provision of easy and predictable prey, however it is unknown to what extent jaguars consume turtle carcasses and how the jaguar population responds to limited turtle availability outside of nesting season. This study took advantage of the accessible nature of jaguar-predated turtle carcasses on Tortuguero Beach over a two year period (2011)(2012)(2013), to provide a novel analysis of carcass utilization rates by jaguars and determine the effects of temporal fluctuations in green turtle nesting numbers. Camera traps were set-up on freshly predated turtles to capture jaguar activity across both Peak and Non Peak green turtle nesting seasons. Thirteen individual jaguars (five males, five females, three cubs) were captured returning to 77% of monitored turtle kills (60% Peak; 95% Non Peak). During Non Peak season, the number of jaguars per kill increased (H(1) = 15.91, p < 0.001) and total jaguar feeding time per kill also increased (H(1) = 13.34, p < 0.001). The propensity for tolerated scavenging or sharing during Non Peak season is illustrated by four adult jaguars captured interacting with a kill at separate times over two nights in October, 2012 (two males, two females). There were no significant differences between males and females, although there is a tendency for the latter to handle the prey to a greater extent. Although marine turtles may not to be a primary prey species, they play an important role in subsidizing the jaguars in this study. The increased kill utilization rates and prey sharing displayed by the jaguars, ensures optimal foraging during periods of low prey availability. These apparently atypical feeding behaviors may be unique to Tortuguero, however their prevalence across the jaguar's range should be considered.