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

Abstract

This 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.