How Sleepy Are Sloths and Other Lessons Learned
Smithsonian scientists use radio technology to track animals in an island jungle in the middle of the Panama Canal
- By Megan Gambino
- Smithsonian.com, February 03, 2010, Subscribe
Hoots, chirps and the guttural wails of howler monkeys fill the humid, earthy air as we trek deeper. From floor to canopy, the tropical forest is crawling with creatures, and my guide, Robert Horan, keeps a running commentary. Spider monkeys flounce in the tree branches. Two bats cling to the inside of a hollow tree. Stingless bees swarm around a honey-like goop oozing from a freshly cut log. Ant birds keep guard over a bustling ant highway, and a land crab scuttles out of the way of our plodding feet. Not to mention it’s chigger season on Barro Colorado Island.
With all the wildlife vying for my attention, I just about pass the 130-foot radio tower, when Horan calls it out. I tilt my hat back, wipe the sweat from my brow and look up. The tower, like the soaring trees surrounding it, is the first evidence of the island being wired.
An aerial view of the six-square-mile research island in the Panama Canal would reveal six other towers poking through the treetops—all part of a cutting-edge animal surveillance system scientists call the Automated Radio Telemetry System, or ARTS. Atop each tower is an array of antennas that, every few minutes, receives signals from up to 20 radio-tagged animals roaming the forest. The towers then communicate real-time information on the locations and activity levels of the animals to an on-site laboratory.
“It’s better than anything we’ve had before,” explains Horan, a visiting scientist from the University of Georgia.
Roland Kays, curator of mammals at the New York State Museum, and Martin Wikelski, an ecologist at Princeton University, the masterminds behind ARTS, were all too familiar with the limitations of other animal tracking methods. In the past, the scientists spent a sizable amount of time on a variety of projects running through the forest, tracking tagged animals with hand receivers. “You do that long enough, listening to those beeps and collecting relatively little data, and you start thinking, is there some better way?” says Kays.
They researched the radio towers and transmitters and decided that Barro Colorado Island (BCI), where the Smithsonian Tropical Research Institute has an outpost, was the ideal place to test them. The field station, which has been around since the 1960s, has labs that can support the system and dormitories to sleep the nearly 300 scientists who visit and conduct studies on the island each year. The seven towers were erected in 2002, and the first data began streaming into the computer lab in 2003.
Once an animal is collared, the towers check in on the creature every four to five minutes, 24 hours a day, seven days a week. This vigilance allows researchers to know, by a process of triangulation, each tagged animal’s location; whether it’s on the move; what routes it takes; and if it interacts with other tagged animals. When one flat-lines on the computer, researchers know that either it, or its transmitter, is dead and to go out in the forest to assess the damage.
The experiment, perhaps the most groundbreaking to happen in BCI’s storied history, seems a little Jurassic Park meets Nineteen Eighty-Four to me. But Kays insists that the researchers aren’t just sitting there in the lab with their feet on the desk, watching the data come in. “We’re out in the field all the time,” he says.
The two-and-a-half-hour hike Horan and I take is enough to convince me of this. We trek along riverbanks hoping to spot a trolling crocodile or a bathing tapir, but are greeted by some turkey-like crested guan instead. We pass cages along the trail as well. “For catching ocelots,” Horan explains.
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Comments (3)
I have a biology degree from the uk and I would like to research soths in Panama. I would like to ask if their are any scientists from the research in Boco or Panama City that I can speak to about this. I am coming over in October to see if I can come in and meet and chat with a few people in Boco and Panama City.
I am also happy to help out on other projects.
The above also has given me the drive to finish my thesis for submission 15th November.
Posted by Karen Wilkins on July 24,2011 | 06:42 AM
Interesting.
The story uses the phrase "rodent-like agoutis" which implies agoutis are similar to rodents but not rodents. But that's incorrect; agoutis are true rodents, in the family Dasyproctidae. There are about 10 species of agouti, all of which are found only in the Western Hemisphere.
The closest relative to the agouti is the acouchi (two species), which is in the same family and which is the only other type of rodent in the family. Acouchis, which look very similar to agoutis, may be seen in the Small Mammal House of the National Zoo.
Posted by Jack Manischewitz on January 19,2011 | 12:29 AM
This is amazing! I am a Biology student in search of a direction and reading articles like this one inspire me to no end.
Posted by Molly Dieterich on February 6,2010 | 12:11 PM