Be an Eco-Traveler: 6 Essential Tips for Not Disturbing Nesting Sea Turtles

On summer nights, I — Peggy — serve as one of the sea turtle beach-patrol volunteers for the Taiwan Lookoo Island Association (社團法人台灣咾咕嶼協會). I walk the beaches of Xiaoliuqiu, gently educating visitors when I encounter them — asking everyone to avoid using white lights on the beach — and, more importantly, documenting all kinds of data when a female sea turtle comes ashore to nest. The vast majority of sea turtles we encounter on Xiaoliuqiu are Green Sea Turtles.

Sea turtles have an instinct to return to the place where they were born to lay their eggs. They take more than 20 years to reach sexual maturity, and the females that come to Xiaoliuqiu to nest may have traveled from Penghu, the Philippines, Orchid Island, or Okinawa — journeys of hundreds of kilometers.

Sea Turtle Nesting: Like Nature's Own Random Performance

Green Sea Turtles come ashore to nest on average once every 2 to 4 years. When a female enters her nesting cycle, she may return to lay a new clutch approximately every 10 to 18 days, producing up to 7 to 8 clutches in a single season, with an average of 60 to 130 eggs per clutch. As plentiful as that sounds, it isn't quite as it seems. Sea turtle eggs take approximately 55 days to hatch, and unlike chicken eggs, turtle eggs have soft shells — they can be punctured and eaten by snakes before the embryos have even fully formed.

Hatching success is very much a matter of luck. Not every egg successfully develops and hatches. According to hatch-rate data recorded by Lookoo Island Association volunteers, some clutches have achieved rates as high as 99%, while others — hit by natural disasters or extreme heat — have seen rates fall to 0%. And even after hatching, the hatchlings face a gauntlet of predators the moment they emerge from the sand: crabs, seabirds, and once in the water, virtually any marine creature can swallow a tiny, soft-bodied hatchling. As a result, the survival rate from egg to adulthood is just 1 in 1,000.

The survival rate from egg to adulthood is just 1 in 1,000.

The first step when a sea turtle comes ashore to nest is to use her front flippers to dig a large body pit, burying herself into the sand. She then uses her hind flippers to excavate an egg chamber roughly 60 to 80 cm deep. Once that is done, she begins laying. She then uses her hind flippers to pack the sand back into the egg chamber, followed by her front flippers to scatter sand widely over the surface, concealing the nest. After completing the entire process, she returns to the sea. The whole nesting sequence takes at least about 2 hours and often considerably longer — just finding a suitable location can take a great deal of time. Nest sites are typically set some distance from the tide line to prevent eggs from being washed out to sea, and are very often found at the boundary between sand and beach vegetation.

Spots with shrubs offering shade are particularly favorable, because a sea turtle's sex is determined by the temperature of the sand around the nest: above 28°C produces males, above 30.3°C produces females, and temperatures in between yield a random mix.

2024: The Nesting Story of a Sea Turtle Named Liang Liang

Nearly all the Green Sea Turtles we encounter on Xiaoliuqiu come ashore only at night. This particular turtle was the exception — the first time she came ashore was in the still-light afternoon, just past 5 p.m., which earned her the nickname "Liang Liang" (亮亮, meaning "bright").

That night, by just after 7 p.m. we already spotted tracks in the sand — meaning she had already come ashore once, failed to nest, and returned to the sea. Female turtles often can't succeed on their first attempt: they may dig and hit a large rock, a tree root, or buried rubbish, or simply decide they don't like the spot and move on. Sometimes they tire out and head back into the water, only to return again a little later.

Liang Liang was exactly that kind of turtle — quick to give up, yet remarkably persistent in coming back to try again, sometimes hauling herself ashore 3 to 4 times in a single night. During my four consecutive nights of beach patrol, I encountered her on three of them. Other volunteers told me she had been coming ashore repeatedly for nearly a week before I arrived, without success. On all three nights I met her, she still failed to lay — it was only several days later that she finally managed to nest successfully.

It really was a hard-won victory. After all of Liang Liang's painstaking searching and selecting, Typhoon Gaemi arrived just a few days later, making the odds of successful incubation significantly harder. We can only hope that every clutch on that beach stays safe.

Watching Liang Liang abandon one large pit after hitting that big rock, I desperately wanted to help her dig. In reality, all we can do is stay well back and never disturb them. When she comes ashore, we have to become rocks — always watching which way her head is turned, keeping ourselves in her blind spot and lower field of vision, in a kind of slow-motion game of hide-and-seek.

What Can We as Humans Do?

• Minimize visits to the beach at night.
• Never use white lights or strobes on the beach.
• If lighting is absolutely necessary, use red light.
• If you happen to encounter a sea turtle, freeze — become a rock.
• Pick up any rubbish you see on the beach; removing even one piece of debris could spare a hatchling from having to climb over one more obstacle.
• Reduce single-use waste — bring your own water bottle and utensils. Small islands have no capacity to absorb large volumes of rubbish; what piles up at the dump can be blown straight into the sea by a single gust of wind.

Related Links

• Taiwan Lookoo Island Association
• Peggy's Wonder Journey

Further Reading