for National Geographic News
At 12:30 p.m. on a clear October day in the mountains of eastern Cuba, Luis Orlando Melian Hernandez lifts his binoculars to the sky. "Look, look!" he points triumphantly, as two ospreys soar overhead. These are his first two osprey sightings of the day. But there are many more perched out there, biologists say, especially that time of year. "Eastern Cuba is a majorpossibly the majormigration corridor for ospreys in the world," said ecologist Keith Bildstein, director of conservation science at Hawk Mountain Sanctuary in Kempton, Pennsylvania.
Melian and colleague Freddy Santana are working to make sure things stay that way. In cooperation with researchers in the United States, the Cuban ornithologists are spearheading efforts to track ospreys that migrate through Cuba, educate Cubans about the birds, and recruit volunteers to protect them. Ospreys are not endangered, but the majestic raptors can make powerful spokesbirds for environmental preservation, Melian said.
"Ospreys are a symbol," said Melian, who has hung a stuffed osprey on the wall of his home in Santiago de Cuba. "If I can protect the osprey, I don't just protect one bird. I protect everything: the trees, other birds and animals, everything."
Ospreys can also act as a sort of canary in a coalmine, because they are extremely vulnerable to pesticides and other toxins in the environment. DDT caused their numbers to plummet in the second half of the 20th century, and populations rebounded only after the chemical was banned. "Fluctuations in their populations provide human populations with an early warning system of negative changes in the environment," Bildstein said. "Ospreys are incredibly effective monitors of ecosystem health."
As environmental watchdogs, ospreys also make an especially good choice because they cover a lot of territory. The birds live on every continent but Antarctica, and they can survive almost anywhere, as long as they can access fish and water.
Ospreys are also famous for their impressive feats of migration. By hitchhiking on waves of rising warm air, individual birds sometimes travel thousands of miles in a single season. "The osprey is one of the most naturally cosmopolitan of all birds," Bildstein said. "They really are a world species."
For years, scientists in the United States have been piecing together a picture of North American osprey migrations by tagging them with radio collars and conducting periodic counts in key locations. The researchers have tracked birds from almost every state in the country to points farther south to spend the winter months in Central and South America. And they have identified a few favorite stopping places along the way. "One of the things we noticed early on was the preponderance of birds that migrate through Cuba and Haiti on their way to South America," said Mark Martell, an osprey biologist in St. Paul, Minnesota, who worked with the Raptor Center at the University of Minnesota on the tracking projects.
Most ospreys that live in the eastern third of the United States swing through Cuba on their way south starting in July, Martell said, and then again on their way back in the spring, between January and April. The birds seem to especially like eastern Cuba's Gran Piedra National Park in the Sierra Maestra mountains. When they get there, some birds may spend three weeks or more in Cuba, resting and fueling up for the rest of their journey. Some stay the whole winter.
Only recently have the Cubans begun to recognize the magnificent flocks in their midst. During a census in the summer of 2001 at Gran Piedra, the American and Cuban scientists counted 279 ospreys in only two and a half hours. By comparison, at Hawk Ridge in Duluth, Minnesota, one of North America's most important osprey-nesting sites, researchers usually count about 260 ospreys in an entire season.
Now, the Cubans are taking action. They have built a migration count station at Gran Piedra, complete with a small biological station for visiting scientists to sleep and work, though Melian, for one, prefers to camp.
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