First Ever Census Of Jaguars Completed; New Technique Could Determine Accurate Population Of Big Cat

The team looked at a population of jaguars living in the Cockscomb Reserve, a dense tropical rain forest in Belize, which WCS helped establish as the world's first jaguar reserve in 1986. Using a grid of remote camera traps set along game trails, the team followed a rigid statistical analysis to determine population density. They now estimate that 14 jaguars live in a 55-square-mile area – a density of big cats comparable to some of the most productive tiger habitats in India.

According to the WCS scientists, the new methodology can now be applied to other areas throughout the jaguar's sprawling range from Argentina to the southwestern United States. It can finally determine not only how many cats are out there, but more importantly, where conservationists should focus efforts to preserve jaguar populations.

"Up to this point, scientists have based their efforts as to where to protect jaguars largely on anecdotal evidence," said WCS conservationist Dr. Linde Ostro, who along with her husband Dr. Scott Silver, conducted the Cockscomb census. "With this new methodology, conservationists can focus often limited resources in the best areas."

The camera trap methodology to census tigers began ten years ago in India, when WCS conservationist Dr. Ullas Karanth used the cat's stripe pattern -- unique to each individual -- to count animals captured on film. A jaguar's spotting pattern is also unique, which allowed Drs. Ostro and Silver to analyze how many animals frequented their study area.

"The methodology can be used for any cat with a unique striping or spotting," Dr. Ostro said. "It's much more efficient than collaring individual animals, then tracking them for years."

The research was funded in part by Jaguar North America as part of a five-year one million-dollar grant to WCS's Jaguar Conservation Program, which is working to save jaguars throughout their range.