After almost two years, I finally returned to the Peruvian Amazon. This time I was equipped with 180 camera traps to set out in a large grid covering two Forest Stewardship Council-certified logging concessions. For three months these camera traps will be taking thousands of pictures of a wide variety of mammals and terrestrial birds, but we are particularly interested in the jaguar. Our previous research showed that our study site had a high density of this top predator, so this time we set out one of the largest camera-trap grids ever used in the Amazon to get a more accurate estimate of their population size.
With a pickup truck full of equipment and supplies, two motorbikes, and a team of eight researchers, field technicians, and volunteers, we left the town of Puerto Maldonado along the Interoceanic Highway. After about two hours, we turned off the paved road through a guarded gate into the forestry concessions. From there it was another four hours on bumpy dirt roads to reach the camp we left in 2012. Our main tent platform was overgrown with vines, and the plastic tarp that made up the roof of the kitchen had collapsed. But a few hours with a machete, some new wooden posts, and some string got the site back in shape, and soon we had a comfortable camp that was going to be our home for the next two weeks until we moved to the second concession.
Our plan was to set up the cameras along the network of logging roads covering the concessions. From previous work, we knew that jaguars frequently use open roads for long-distance travel, and we were much more likely to photograph them there than in the dense forest. Plus, the roads would give us easy access by truck or motorcycle. However, not only had the tent site overgrown since we left but some of the logging roads we were driving down two years ago had also turned into dense thickets. For us, this meant more walking and trail cutting and less driving. Many camera-trap locations were 6 to 10 miles (10 to 16 kilometers) away from the camp and required hiking in for several days, camping along the way. Fortunately, we had a team of experienced field technicians who know the forest like the back of their hand.
While cutting one’s way through dense vegetation is hard work, it is also one of the best ways to get to know the forest. One realizes that the Amazon is made up of a mosaic of different vegetation; tall old-growth patches with huge trees quickly turn into bamboo thickets or dense undergrowth recovering from a tree fall. We were lucky to watch tapirs and jaguars walk along the logging roads, spider monkeys curiously looking at us from treetops, and a harpy eagle with a monkey in its talons swooping across the road right in front of our car. And when we checked some of the cameras after two weeks, we already discovered several jaguar photos. I am sure there will be many exciting surprises when we go back to pick up all the cameras in October.
Mathias Tobler, Ph.D., is a scientist with the Behavioral Biology division of the San Diego Zoo Institute for Conservation Research. This research is supported by the Disney Worldwide Conservation Fund and World Wildlife Fund (WWF) Switzerland and is carried out in collaboration with WWF.