Individual Jaguars Research Articles

Identificación de individuos de jaguares (Panthera onca) y pumas (Puma concolor) a partir de morfometría de sus huellas (Carnivora: Felidae)

Estimating feline abundance becomes particularly difficult, sometimes impossible, due to their elusive behavior and extensive space requirements. Available techniques are expensive and/or poorly efficient, therefore alternative methods are needed. The objective of this study was to assess the possibility of identifying individual jaguars and pumas based on morphometric analyses of their tracks. The footprints of five jaguars and four pumas were drawn and the foot (hind or fore foot, left or right foot) and the substrate were recorded. We took 16 measures from each footprint including lengths, widths, areas and angles. Variables were analyzed by using Principal Component Analysis (PCA) and substituted by the first Principal Component (PC) (> 70% variance). We assessed the effect of the substrate and type of foot by means of paired t-student tests, and found differences between fore and hind feet and footprints from the same individual when made on soil or sand. No differences were found between right or left feet. The footprints changed over time as revealed by Multiple ANOVA. Different individuals could be identifyied based on discriminant analyses with more than 70% confidence. We conclude that this method is feasible and can be useful when studying endangered felines.

Estimating the density of a jaguar population in the Brazilian Pantanal using camera-traps and capture–recapture sampling in combination with GPS radio-telemetry

The jaguar (Panthera onca) is the largest feline in the Americas and third largest world-wide, smaller in size only to the tiger (P. tigris) and lion (P. leo). Yet, in comparison, relatively few studies on jaguar population densities have been conducted and baseline data for management purposes are needed. Camera trapping and capture–recapture sampling methods were used to estimate the size of a jaguar population in the Pantanal’s open wet grassland habitat, an important area for the long-term survival of the species. This study is the first jaguar population estimate conducted in co-operation with a GPS-telemetry study providing an important opportunity for comparing different methods of density estimation. An accessible area within a 460km2 privately-owned ranch was sampled with equal effort during the dry seasons of 2003 and 2004. Thirty-one and twenty-five individual jaguars were identified in 2003 and 2004, respectively. Estimates of jaguar abundance were generated by program CAPTURE. Density estimates were produced according to different methods used to calculate the effectively sampled areas which ranged from 274 to 568km2. For 2003, the currently-used mean maximum distance moved (MMDM) method produced a density of 10.3 jaguars/100km2, while GPS-telemetry-based calculations produced a mean density of 6.6 jaguars/100km2. For 2004, the MMDM method produced an estimate of 11.7 jaguars/100km2 while GPS-telemetry calculations produced a density of 6.7 jaguars/100km2. Our results suggest that the widely-used MMDM method used to calculate effectively sampled areas is significantly under-reflecting maximum distances moved by jaguars and their range-use and, thereby, considerably inflating cat density estimates. This overestimation could place a population in a difficult situation by lengthening the time taken to initiate protection measures because of underestimating the risk to that population.

One thousand jaguars (Panthera onca) in Bolivia's Chaco? Camera trapping in the Kaa‐Iya National Park

AbstractThis paper reports on efforts to trap jaguars Panthera onca on camera in the dry forests of the Kaa‐Iya del Gran Chaco National Park in Bolivia. Ad hoc camera trapping provided certain information on jaguar presence and habits, but was limited in application. Activity patterns showed that jaguars are active all day, particularly at one of three sites, with peaks in the morning and evening the more common pattern. Minimum observed home range was variable, with males (up to 65 km2) occupying more area than females (up to 29 km2). The authors adapted systematic methodologies first developed to survey tigers in India, based on individually distinctive pelage patterns in tigers and jaguars. Abundance is estimated using capture–recapture statistical analysis, and a sample area defined based on the maximum distance that individual jaguars move during the sample period. The methodology has proved successful for jaguars in dry Chaco forest, population densities of 1/30–45 km2 and 1/20 km2 are estimated in the two most extensive landscape systems of Kaa‐Iya. The entire 34 400 km2 protected area is estimated to sustain a population of over 1000 adult and juvenile jaguars, the largest single population of jaguar reported anywhere, and a viable population for long‐term jaguar conservation.