An isolated Pacific Ocean island off Costa Rica is confronting a decidedly urban problem. A vast horde of rats, scientists say, is threatening endemic species and fragile ecosystems on Isla del Coco, a rainforest-cloaked island and conservation area 300 miles (495 kms) and 36 hours by boat from Costa Rica’s Nicoya Peninsula. A study completed last year by Colombian researcher Juan Ricardo Gómez revealed that the tiny island, which measures just nine square miles (24 sq km), is overrun by an estimated 210,000 rats. “These are numbers one might expect to see in the sewers of Tegucigalpa or New York City, not in a wild rainforest,” Gómez says. The rats eat virtually everything, from insects to seabird eggs and the seeds and shoots of... [Log in to read more]