image: Every year during the dry season in Brazil's Abufari Biological Reserve, a mass hatching of Giant South American river turtles occurs, an event that produces hundreds of thousands of turtle hatchlings. Researchers from the Wildlife Conservation Society and the Chico Mendes Institute for Biodiversity Conservation recently witnessed the emergence of an estimated 210,000 hatchlings. The scientists marked and released a total of 15,000 hatchlings in the space of several days. The method -- known as "mark and recapture" -- allows researchers to estimate the size of an animal's population, particularly when counting every individual is difficult. view more
Credit: C. Ferrara/Wildlife Conservation Society