Yakushima is an important site for both the endangered loggerhead and green turtles. Both turtles visit Yakushima to nest on its beaches so a visit to the island has plenty of opportunities for turtle-watching. The island is the main North Pacific nesting site for the loggerhead turtle with the major nesting sites at Nagata, Isso, Kurio and Nakama – Nagata being the most popular.
Female turtles visit Yakushima between May and August, returning to the area where they were born approximately 30 years previously. Over a period of a month or so they come ashore several times to lay their eggs in clutches of between 100 – 120. Babies hatch out depending on the incubating sand temperature between 45 to 70 days later. Turtle-watching eco tours are available over the summer months. Please be sure to book in advance as there are a limited number of people allowed on the beach each night. DO NOT attempt to go on the beach without a trained guide as you are highly likely to disturb these sensitive creatures during their laying cycle. If you don't have time to book a guide, then stroll along any of the sandy beaches early in the morning and you are likely to see fresh turtle tracks winding across the sand. The turtles lay their eggs above the high-tide line, so please avoid walking in this area over the summer months. You CANNOT enter the beach at night between 1st May – 31st August. You can only enter the beach with a guide.
Prior to the early 1980's, when Japan introduced legislation to protect sea turtles, the local people harvested turtle eggs as a valuable source of protein. Now many locals volunteer to help keep the beaches clean and protect the eggs. In 1993, the year Yakushima became a world heritage site, the largest nesting grounds at Nagata were also given protected status under the Ramsar Wetland convention. Sea turtles reproduce slowly. Adults only become sexually mature between 30 and 45 years old and they breed every 2 years. The survival chance for a hatchling is believed to be as low as 1 in 5,000 and this means that once a population has declined it takes decades for numbers to recover. Visit the Nagata Sea Turtle Museum (Umigame kan) run by the local NPO to find out more about these beautiful creatures and how to protect them.