The island of Barro Colorado in Lago Gatún is a former hilltop that became an island when the Río Chagres was dammed during construction of the Panama Canal. It covers 1,500 hectares (3,700 acres) of virgin rain forest and forms part of the Barro Colorado Nature Monument, which includes five peninsulas on the mainland and protects an area several times that size. The reserve is home for more than 400 species of birds, 225 ant species, and 122 mammal species, including collared peccaries, ocelots, coatis, and five kinds of monkeys. Its forest has 1,200 plant species—more than are found in all of Europe—ranging from delicate orchids to massive strangler fig trees.
In 1923 the island was declared a biological reserve and a tropical research station was built there; it is now the oldest such facility in the world. The island is administered by the Smithsonian Tropical Research Institute (STRI), which facilitates research by 200 or so visiting scientists and students per year
and runs several weekly educational tours. Those tours are not only one of the most informative introductions to tropical ecology you can get in Panama, they are excellent opportunities to see wildlife; after decades of living in a protected area full of scientists, the animals are hardly afraid of people.
Bring your passport, tour receipt, bottled water, insect repellent, binoculars, and a poncho or raincoat (May–December). Wear long pants, hiking shoes, and socks to protect against chiggers. You should be in decent shape, since the tour includes several hours of hiking on trails that are steep in places and can be slippery; children under 10 are not allowed, students pay a discounted rate. You can reserve and pay for tours at the STRI website, or through one of the city's tour companies that specialize in nature tours; the tour companies will charge extra to book the STRI tour and provide transportation between your hotel and the dock in Gamboa.
Smithsonian Tropical Research Institute. Barro Colorado can be visited on full-day tours run by the Smithsonian Tropical Research Institute (STRI), which depart the STRI dock in Gamboa at 7:15 on Tuesday, Wednesday, and Friday, and 8 on Saturday, and Sunday. The $70 tour is well worth the money, since the English-speaking guides do an excellent job of pointing out flora and fauna and explaining the rain forest's complex ecology. Lunch in the research station's cafeteria and boat transportation to and from Gamboa are included. Tours should be booked and paid for a minimum of 15 days in advance, months ahead for weekends between December and April through the STRI Web site. Reservations that haven't been paid for 15 days before the tour will be canceled. If you failed to reserve, they sometimes have spaces available; it's worth calling Tamara Castillo at the STRI office and asking whether there is a space. Last minute tours can be paid for at the Corotú Bookstore, in the Tupper Center, on Cerro Ancón. Av. Roosevelt, Cerro Ancón, Panama City, 0308. 507/212–8951. www.stri.si.edu. Open Mon.–Fri. 8 am–1pm.
Isla Barro Colorado, Panama