Between 2002 and 2015, scuba divers dove around 53 islands and coral reefs throughout the U.S. Pacific around Hawaii and conducted a comprehensive survey of the sea turtle habitats in the area. They counted about 3,400 sea turtles over 90% of which were green sea turtles, with the remaining 10% being a mix of hawksbill sea turtles and unidentified species.
In PLOS ONE, the team reported that the sea turtle population around the Hawaii islands increased by approximately 8% per year, whereas around the American Samoa the numbers are increasing at around only 4% per year, an amazing finding from a conservationist’s point of view according to oceanographer based in Honolulu, Rusty Brainard.
The International Union for Conservation of Nature named green sea turtles as endangered (Chelonia mydas), whereas the hawksbill type turtles are listed as critically endangered, leaving their situation more rocky with populations dwindling.
Until now, limited information had been attained on the status of these sea turtle populations especially on their ability to survive after being hatched on the ocean shore. In order to monitor the turtle’s progress and spot them, scientists were attached to slow moving boats by a line that moved them slowly across the top of coral reefs, allowing for good visibility in the natural habitat of these turtles. Brainard went on to describe the sea turtles’ movements as graceful and gliding along the caves of the reefs or having a nap in the alcoves. They mentioned that sometimes the scientists would accidentally snag onto bits of the reefs and break some of the bits off, a challenge that the sea turtles experience themselves in their struggle to find comfortable places to live.
Other dangers that the reptiles face includes global warming, which results in increased sea levels and thus habitat loss. Last year, it was found that the East Island of Hawaii was mostly submerged during the Hurricane Walaka, leaving this nestling site uninhabitable, at least temporarily.
In addition, they face the dangers of hunting and harvesting for consumption by humans. However, the Endangered Species Act, which the turtles are covered under, protects them from these dangers, limiting but not eliminating the threat. This legal protection is probably the main reason that these turtles have made a comeback, highlighting the importance of this type of legislation for the bettering of ecosystems.
The new study gives researchers a more complete idea of how the turtles are faring in the larger ocean community. While the status of Hawaiian populations are well-known, the status of these turtle species around the other islands investigated had not previously been established.
However, according to James Spotila, a biologist at Drexel University in Pennsylvania, more information about these ocean populations is unlikely to be attained in the near future, as NOAA has halted its efforts to conduct towed-diver surveys of these Pacific areas. Overall, this data is a big win for conservationists and attests to the fact that human efforts to preserve species do not go unnoticed.
Image Credit: Deege- Flickr