The AGOUTI'S Nutty Friend - inter-dependence of the Brazil nut trees and the reclusive animals called agoutis

International Wildlife, March-April, 2000 by David Taylor

In his work as agouti detective, Ortiz has learned to identify individual animals' trademarks. "Look at this one," he said, holding a pod with a hole shaped like a small jack-o'-lantern's smile. "Every agouti has a signature. You find some holes are oval-shaped, some are star-shaped, some are heart-shaped." Like a criminal with a telltale modus operandi, an agouti will open nuts with the same kind of hole every time, at the same point on the pod.

An agouti's burying activity is designed to ensure its survival through a lean season, but it also helps other animals. Peccaries, for example, search the agoutis' haunts for the protein-rich nuts, digging into the dirt around fallen logs on the chance of finding a horde. Eight other species, including pacas, pacaranas, spiny rats and porcupines, also steal Brazil nuts stored by agoutis. In addition, several frog species owe their survival to the agouti-Brazil nut relationship. Researchers in Brazil found that the poison arrow frog, for one, relies almost exclusively on rain-filled Brazil nut pods for water to get through the tadpole stage.

I stopped on the path to catch my breath. Ortiz reminded me that casta- eros walk this path with 150-pound loads of nuts on their backs. Sometimes they carry the loads as long as two hours to a boat landing. From there, the nuts are as good as money: Casta-eros can trade sacks of nuts for everything from canned goods to medical treatment. The profit margin of the Brazil nut harvesters, however, remains cloudy. For that reason the project is keeping careful records to see how much a natural forest repays collectors, who work concessions--averaging 2,500 acres each-- granted by the government. These records can show hard-nosed loan officers that a family's Brazil nut concession is at least as good an investment as a cattle farm. Not to mention a much better investment in biodiversity.

Where casta-eros manage a forest concession for Brazil nuts, there is a legal and economic basis for protecting the area from destructive land uses such as cattle ranching and mining. The Casta-ales Project and other environmental groups have convinced the government to lengthen the concession periods from two years to five. Longer time frames give collectors a stable basis for their enterprise and incentive to manage their area with an eye for its long-term health--for example, protecting seedlings to help natural regeneration.

After a brief rest, we moved on through the forest, but failed to spot an agouti on our hike. We spent the next day at another part of the concession, where the path was overgrown and the machete rang like a bell against the lianas. No agouti sighting.

My last day in the forest, in a final bid to glimpse one, I walked up the path at dawn and again at twilight, when agoutis are most active. I kept still and focused on watching. Fifteen minutes passed, then thirty. As daylight faded, fireflies started to spark high above in the canopy.

Suddenly I heard a noise nearby.

It was Ortiz, coming down the path. Dispirited, I complained that I'd waited in vain for agoutis. "They are secretive. People rarely see them," he said consolingly.