A BRIEF HISTORY OF CANOPY RESEARCH
Access to the equatorial jungle has proved no less difficult for research biologists than for conquistadors and filmmakers. Consequently, it is only in the last two decades that scientists have begun to realize the immense importance of the rain forest canopy as a repository of biodiversity. Until biologists “began climbing trees,” says Dr. Margaret Lowman, a leading canopy researcher, “people thought that maybe there were a couple of million species on Earth.” Now estimates range as high as 30 million, she says. Speaking by phone from her office at New College of Florida, Lowman notes that just as scientists are beginning to understand the vast range of rain forest species, deforestation is devastating equatorial regions. Like many canopy scientists, she sees herself in a race against time: Can biologists even catalog these organisms before we wipe them out?
“Forest Canopies,” a book that Lowman co-edited, chronicles the history of canopy science. One early technology for collecting samples was trained monkeys; later, biologists donned rock climbing gear and ascended trees themselves. Though most canopy researchers today feel comfortable rappelling, Lowman says that “scientists soon realized that ropes and harnesses are not a good way to do this work.” In the 1960s, British and German researchers began slinging walkways high up between trees. In the past 20 years Lowman has been a champion of what she calls these “highways in the sky,” and there are now several dozen around the world, from Belize and Costa Rica to Sarawak, Australia, and the Myakka River State Park in Florida. Some, like the one in Florida, whose design and construction Lowman supervised, also are open to the public. More recently, researchers have begun to erect giant cranes to cantilever cabins out over the tops of the trees, affording access to several acres of forest.
All of these methods have an important place in the spectrum of canopy research, but for Graham Dorrington something was missing. He draws an analogy with the oceans: When researchers first ventured underwater, they were tethered to their ships by air hoses, their explorations confined to an area surrounding the boat. The bathysphere enabled scientists to move around freely, while scuba diving equipment eventually made that experience available to everyone. For Dorrington, walkways and cranes are like undersea tethers. Only a free-ranging craft, he says, will give canopy biologists full access to the arboreal realm.
Dorrington’s is not the first lighter-than-air vehicle to be used for canopy research. Beginning in the late 1980s the French scientist Francis Halle mounted a series of expeditions to study canopy life using a huge hot-air balloon. As one of the chief scientists in Halle’s expedition to Cameroon, Lowman praises his vision but notes that such large-scale operations also require large sums of money. Cranes, too, cost several million dollars apiece. In the scheme of contemporary science, several million dollars for a decade of exploration is not a particularly large amount, but, sadly, rain forest research has never been high on most countries’ scientific agendas.
“We are all very aware of the need for small-scale operations to do research on a daily basis,” Lowman says. What makes Dorrington’s approach so exciting, she adds, is that “potentially it’s replicable, portable and relatively inexpensive.”
