The challenges on these trips, he said, begin with travel to the field site.
The journey includes passage on a boat packed with several hundred people as it winds its way up a river deep into the rainforest.
Just about everyone—including tourists in search of authentic experiences—sleeps in hammocks they string up on deck. So "you often wake up with someone's feet in your face," Mellow said.
Passengers who board late a night may find the only place to hang a hammock is over someone else's, he noted.
"You look up and what sags most in the hammock is the butt—and there it is swinging right above your head."
In the Field
Once in the field, Mellow said the newness and excitement of actually doing science can sometimes lead to trouble as well.
For example, Vulinec's research involves following monkeys around the rain forest as they swing from tree to tree. Mellow said volunteers often lose track of where they are—as has he.
When lost, he recommends tourists take a compass reading and walk in increasingly larger circles until they cross the trail back to camp.
In addition, even if the science subject resides up in the trees, people should remain aware of their feet—or they might step on a snake or into a hole.
Ants also pose unwelcome threats, Mellow noted.
"There are ants on everything and some of them can be up to an inch [2.5 centimeters] long, and they sting and bite and there's actually possibility of shock," he said.
In fact, Mellow noted, insects are the biggest nuisances in the rain forest. He advises that volunteers bring plenty of bug repellent, but also enough mental strength to ignore the pests.
"Go with the flow as far as the sweat, the heat, the mosquitoes," he said. "And a good book, a good read is always good when you're done and you're in your hammock."
The African island nation of Madagascar may be a safer choice for less adventurous travelers (Madagascar map).
Summer Arrigo-Nelson is an anthropologist at the University of Notre Dame in Indiana who routinely co-leads a trip to Madagascar to study lemurs. (Related: "Threatened Lemurs' Diet Key to Conservation Efforts, Researchers Say" [February 8, 2007].)
Madagascar has no poisonous spiders or large carnivores that put volunteers at risk, Arrigo-Nelson said.
"Basically the only way people can get hurt is if they themselves have an accident," she said.
And most of those are minor, she noted, such as a volunteer slipping into a river and then pulling in a friend trying to help.
The international nonprofit Earthwatch Institute organizes the trip, and the organizations's volunteer coordinators work closely with ecotourists to match them with appropriate trips.
In Madagascar, for example, volunteers have to hike a lot, so people with bad knees may be better off elsewhere, Arrigo-Nelson said.
"We want everybody to have a good time and to go home healthy," she said, "and we want them to enjoy and remember their experience of Madagascar in a good way."
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