“If one of the turtles goes back to somewhere like the Great Barrier Reef, she might travel as far as 1,800 kilometers in a month,” said Richard Hamilton, Melanesia Program Director, The Nature Conservancy. “These hawksbills have one of the longest intermigration periods in the world; she might not be back to the Arnavons until 2021.”
For comparison, hawksbills that nest in Hawaii travel only ~200 kilometers between nesting and foraging areas.
The program will provide some of the first data on whether the current Arnavon boundaries are sufficient to protect nesting turtles, and where they migrate to in between nesting years. Existing information suggests that they swim to foraging grounds on Australia’s Great Barrier Reef and Papua New Guinea. But this data comes from a mere five turtles, only two of which were satellite tracked showing the exact migration routes. This new study will help the Conservancy and community partners protect turtles throughout their lifespans, and offers hope as World Sea Turtle Day is celebrated on June 16th.
Like many other sea turtle species, hawksbills are critically endangered. Worldwide populations have declined about 80% in the past three turtle generations due to the illegal turtle shell trade, egg collection, harvesting for meat, bycatch in tuna fisheries, and habitat loss from beach development and climate change.
“Turtles are at 10% of their numbers they were at a century ago, and roughly only one out of every 1,000 turtle eggs make it to adulthood,” said Hamilton. “This remarkable recovery in the Arnavons shows that changes in policy, inclusive community-based management, and long-term commitment can turn the tide for one of the most charismatic and endangered species on our planet.”
With assistance from The Nature Conservancy in 1995, the Solomon Islands government and the communities of Kia, Katupika, and Wagina established the Arnavon Community Marine Conservation Area (ACMCA), creating the largest and first community-managed marine protected area in the country. As of 2012, an estimated 400 to 600 hawksbills nest here annually, migrating thousands of kilometers back to their natal beach. These hawksbills nest only once every seven years, on average, so the total Arnavons nesting population is between 2,000 and 4,000 turtles.
Those numbers are a fraction of the tens of thousands of turtles that nested here before the shell trade nearly eliminated the species entirely, yet it’s still an encouraging trend. Data collected by ACMCA conservation officers shows the number of nests on the Arnavons has more than doubled in the two decades since establishment of the protected area.
Protecting the Arnavons is not enough. Females in this population nest once every seven years on average, spending just a few months in the protected area before returning to their distant foraging grounds. Once out of the Arnavons the females are on their own — and scientists not entirely sure where they go. This tagging program will help answer that.
The trackers send out GPS signals that are uploaded whenever the turtles come to the surface. Using these GPS fixes, The Nature Conservancy’s scientists will map and analyze the turtles’ movements to get a better picture of their nesting, migration, and feeding behaviors. The data will also help determine if the existing ACMCA boundaries are sufficient to protect hawksbills while nesting. After about a year, the adhesive will disintegrate, allowing the trackers to fall off. But in the meantime, we’ll be able to gather a wealth of scientific data about the hawksbills and their travels.
Sadly, two of the tagged turtles were poached shortly after their tags were installed — a sobering reminder of the dangers that sea turtles face every day. The Conservancy is using this incident to continue discussions with local communities about turtle conservation and the value of protecting turtles. It also shows there is an obvious need for more support for patrols to help enforcement. The Conservancy is already developing a plan to address this issue.
A video about the project is available.
The migrating sea turtles will also help raise awareness by serving as conservation ambassadors. The Nature Conservancy offered local communities, school children, and donors the opportunity to name the turtles. Follow them on a turtle tracking map.