“If you are quiet, you might hear something,” I reminded myself as I tried to avoid stepping on the crisp, curled leaves littering the trail. During Costa Rica’s dry season from December to April, deciduous trees lose their leaves in order to conserve moisture. Dry leaves crunch loudly underfoot even in a tropical wet forest and serve to warn animals away from predators, so I would often stop and listen quietly and patiently for an animal to reveal itself. How elusive they are! At least 68 species of mammals and 94 species of reptiles and amphibians make the 330 hectare nature reserve of Hacienda Baru, their home. I could neither see nor hear any of them.
All I could hear was the high-pitched whistle of cicadas, almost drowning out the birdsong. Cicadas sound like crickets and, I am told, look like enormous house flies about the size of Brazil nuts. This is perhaps something I don’t want to see.
As I stopped and listened once again, peering into the thick undergrowth and wondering about the fauna that might be lurking there, a rustling of leaves and the snapping of a branch quickly drew my attention upward. Leaping and swinging single file in the swaying branches ahead was a community of more than a dozen white-faced capuchin monkeys. I slowly crept closer to get a better look at these cute little monkeys that are the most intelligent primate in Costa Rica.
It was obvious how these capuchin monkeys got their name. The black, cap-like section of hair on the monkeys’ heads resembled hoods worn by the Italian order of Capuchin monks. The monkeys’ bodies and tails were mostly black, too, but their faces, throats, and chests were whitish, with their serious-looking faces bare of hair. Quite small, they were no more than one metre in length, of which just over half is prehensile tail.
The capuchins seemed oblivious to my watchful eyes as they foraged for food, carefully searching through leaves and peeling off bark for tasty morsels. These monkeys usually eat fruit and nuts but, being omnivores, will also eat insects and animals such as small birds, butterflies, squirrels, lizards, and crabs. I remembered reading a warning to prospective field workers on a capuchin project: “You need to be able to stomach the sight of monkeys eating their cute, charismatic prey alive while the prey screams for help.” I had also read about “a troop of capuchin monkeys that killed an egg laden female iguana, ripped her open, ate all the eggs and then ate the iguana.” In spite of the heat, I shivered at these mental images.
As I crept even closer, a monkey nimbly swung to the ground not far from where I stood, oblivious to my presence. He gathered up a piece of fruit in his little hands with amazing dexterity and, before eating it, proceeded to squeeze and smell it, perhaps making sure it was ripe. “A picky eater,” I thought to myself.
No sooner had I come to this conclusion, than a shriek made me jump. As I returned my gaze to the community of capuchins overhead, I was startled to see several pairs of eyes now fastened on mine. One feisty animal had leapt to a tree limb above me, snapped off a branch, and shook it. “Is he threatening me?” I wondered. With an unwavering gaze, he opened his mouth wide to reveal two rows of pointed teeth. Another ferocious-looking capuchin held a smaller one in a protective grip. Both faced in my direction, baring matching sets of sharp teeth.
“Can knee-high capuchins gang up and pick fights with creatures so much bigger than themselves, including me?” I wondered. Not wanting to find out, I backed slowly away. When finally I felt a safe distance had fallen between me and the capuchins and I no longer seemed to pose a threat to them, I turned and began to retrace my steps.
No longer careful to avoid the crisp fallen leaves, I tramped back along the trail, loudly announcing my approach as I went. It’s amazing what animals you can surprise when you are silent in the jungle.