But deliberately set fires have sidetracked the biologists. During one of the most severe dry seasons in the reserve's history, when fires threatened nesting trees, the whole research team turned to creating fire lines.
The poachers took advantage and moved in. Of the 55 eggs hatched in El Peru and El Burral this year, only three fledglings were still in their nest as of last Friday. "About 52 were stolen or eaten by natural predators just over the last few weeks," says McNab.
This year, according to data from CEMEC (Centro de Monitoreo y Evaluación de CONAP), fires have swept through at least 400,000 hectares (1,500 square miles) of Maya Biosphere Reserve.
Land development practices not only increase the fire risk but also impinge on wildlife habitats. By law, a landless Guatemalan can clear unprotected national land, plant crops, and claim title. But the boundary between protected and unprotected lands is often a matter of dispute.
Land-Grabbing In National Parks
"Peasants set fire to the land to clear the forest for farming," says Marie Claire Paiz, a biologist for the Guatemalan environmental organization Fundación Defensores de la Naturaleza and director of the Sierra del Lacandón National Park.
Often small farmers grab land on behalf of wealthy cattle ranchers. "You know this is happening because suddenly someone will buy a series of contiguous plots and move in their animals," Paiz says.
Politics are another complicating factor.
"This is an election year, and there is a complete lack of presence in places where environmental law needs to be enforced," says Jody Stallings, team leader for FIPA, a local environmental project sponsored by the Washington, D.C.-based International Resources Group.
McNab and Paiz feel that the government is unwilling to use force against the local peoplefearing retribution at the polls in November.
Paiz cites a lawless intrusion into an area in Lacandon National Park, close to macaw nestsand filled with Mayan archaeological sites.
About a hundred machete-brandishing squatters have set up there, hunting wildlife like the tapir and looting the sites. So far the police have been ineffective in clearing the area, according to Paiz.
"I have five eviction notices from the judicial system and they are just not executed," says Paiz. "If you can't get rid of invaders on private property, in a national park, then what can you do?"
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