Scientists know that nest temperature determines hatchling sex in sea turtles, as in many other reptiles. But through the ceaseless efforts of hundreds of Earthwatch volunteers who monitored nest temperature probes, biologists have determined exact temperatures needed to produce male or female leatherbacks.
In Malaysia, teams studying green turtles with Dr. Joan Whittier (University of Queensland) and Kamarruddin Ibrahim (Malaysian Sea Turtle Program), teams have shown that developed beaches may be too hot and sunny to produce viable hatchlings in balanced sex ratios. These teams, as well as those studying the impacts of coastal development on hawksbill turtles on Barbados with Dr. Julia Horrocks (University of the West Indies), have randomly tested the viability of hatchlings produced under different environmental conditions. As a result of these ongoing investigations, sea turtle hatchery managers have more precise guidelines for their work, and coastal planners a greater appreciation for the effects of coastal structures on sea turtle survivorship.