Growing a Forest From Scratch

By Jamie Murphy.

Daniel Janzen, 47, is a tenured professor of biology at the University of Pennsylvania, but for the past 14 years his home has been a rented, tin-roofed cabin in an isolated Central American wilderness. The location, Santa Rosa National Park on Costa Rica's Pacific coast, is ideal for his favorite pursuits: rambling across abandoned pasture, collecting seeds and caterpillars, weighing and identifying trapped mice, netting insects by night -- work he calls "muddy-your-boots biology." Janzen, in fact, spends so little time in Philadelphia that he maintains no residence there. He prefers to sleep on a cot in his university office.

Since last year, however, the ascetically inclined scientist has had to put away his muddy boots and pursue a very different kind of fieldwork in big-city hotels and on the lecture circuit. The reason: in collaboration with the Nature Conservancy International, he is attempting to raise $11.8 million for an unprecedented ecological experiment. Janzen plans to use the money to buy 158 sq. mi. of Costa Rican terrain surrounding Santa Rosa and re-create a virtually extinct ecosystem known as tropical dry forest. He has already named the proposed refuge Guanacaste National Park.

Janzen has so far collected $1.3 million from such contributors as the MacArthur and W. Alton Jones foundations and is now negotiating to buy 15.4 sq. mi. of land -- a mosaic of 20- to 50-acre farms, grasslands and plots of forest -- from farmers and cattlemen. He offers the going rate of $200 to $300 a hectare (2.5 acres). With crops and cattle returning marginal profits in Costa Rica, and interest rates exceeding 20%, he has met with little resistance and hopes to purchase the remaining land by February 1988. Environmentalists are cheering him on. "We as conservationists in Latin America have traditionally (preserved) pristine or virgin areas," says Curtis Freese, the World Wildlife Fund's director of Latin American and Caribbean programs. "Janzen is saying that we can look at largely degraded lands and restore them to natural or close to natural ecosystems."

Tropical dry forests differ from rain forests in that their precipitation is seasonal. During the rainy period, the landscape is verdant, but during the five to six months of the year that are rainless (early December to mid-May in Costa Rica), many trees lose their leaves. Unlike the temperate zone's deciduous hardwood forests, however, they do not become fully dormant. Instead, the bare trees flower and bear fruit, which nourishes a variety of mammals and insects. Centuries ago, such vegetation covered 60% of the forest regions of Latin America, India, Southeast Asia, Africa and northern Australia. On the west coast of Central America alone, 98% has been chopped down or burned. Says Janzen: "Tropical dry forest is where what you call endangered is dead, and what you call safe is endangered. They have become the breadbaskets of the tropics."

Janzen has observed that dry forests can re-establish themselves. They need only to be protected from heavy grazing, overhunting and fires set annually by local residents to clear the land. If the forest is allowed to grow back naturally, a closed canopy forms in about 20 years. Aided by planted seedlings, he estimates, regeneration would take only a decade. Rejuvenated dry forest attracts a wide variety of animals, which, in turn, help disperse seeds. In Santa Rosa, the biologist has counted 170 species of birds; 700 species of plants; about 13,000 species of insects, including 3,140 species of moths and butterflies; about 100 species of reptiles and amphibians and 115 species of mammals. Among the trees is the project's namesake, the guanacaste, whose branches can stretch over an acre of land and whose trunk soars 100 ft. Spider, howling and white-faced monkeys swing through the forest canopy. White-tailed deer and peccaries (a kind of wild pig) forage in the underbrush. Jaguars, ocelots, coyotes and gray foxes roam the woods at night. Ridley turtles nest on the park's Pacific beaches. Says Janzen: "Virtually all the species that were there when the Spaniards hit are still around."

Part of his strategy is to make Guanacaste what he calls "user friendly," accessible to local people, researchers, school groups and tourists. He makes a point of instructing visitors in natural history. As a result, he says, "people are no more likely to damage the forest than they are to steal gold candlesticks from the local church." Four ex-farmers have become park guards and are responsible for stopping hunters and preventing or controlling grass fires. Janzen permits the farmers to live in the park and use a portion of the land to raise crops and a few cattle. Limited grazing keeps the grass low and gives woody plants a chance to take hold. By moving the cattle through the rangeland, says Janzen, "we are turning a homogeneous cow pasture into a heterogeneous forest."

The biologist hails the Costa Ricans for their support of the Guanacaste project. Since 1970, Costa Rica has been one of Latin America's most conservation-minded countries. It has set aside nearly 20% of its land for parks and reserves -- more than any other nation in the tropics. Janzen admits that he would not have attempted such a large-scale reclamation project anywhere else. But, he says, "I think this is the way of the future. Guanacaste is a demonstration of the fact that you can grow back a tropical forest if the community that lives around it comes to embrace it as a cultural resource. If we can have that happen over the long term, a lot of the problems of tropical conservation will be licked."

With reporting by Andrea Dorfman/New York