Con Dao as nesting ground for turtles
Con Dao is an island archipelago located off the southern coast of Vietnam, known for its pristine beaches, lush forests, and Con Dao National Park, which covers more than 80% of the land area and extends into the surrounding marine waters as a protected marine park. This isolation and conservation focus have made Con Dao one of the most ecologically significant places in Vietnam, particularly as a nesting ground for sea turtles.
Every year, hundreds of green sea turtles and olive ridley turtles come to Con Dao’s beaches to lay their eggs. The island group hosts 16 nesting sites, with Bay Canh Island being the most important, attracting around 70% of all nesting turtles. The nesting season runs from April to November, with the peak occurring between May and September. During this time, mother turtles swim ashore at night, searching for a safe place to dig a nest around 60 cm deep, where they lay between 80 and 120 eggs. Once the eggs are laid, the turtles camouflage the nests with sand before returning to the sea, leaving the eggs to develop under the watchful protection of forest rangers.
Unfortunately, the number of nesting turtles in Vietnam has declined significantly due to pollution, habitat loss, and illegal hunting. In the 1980s, 10,000 turtles laid eggs in Vietnam annually, but by 2019, this number had dropped to just 450. The Con Dao National Park plays a vital role in protecting these endangered species, ensuring that each year, approximately 150,000 baby turtles are successfully hatched and released into the sea.
Turtle Sanctuary
To protect the declining turtle population, Con Dao National Park has operated a turtle conservation program since 1993, making it Vietnam’s most important sea turtle breeding ground. The program focuses on monitoring and safeguarding turtle nests, rescuing eggs from potential dangers, and increasing hatchling survival rates. Thanks to these efforts, more than 1.5 million baby turtles have been successfully released into the wild.
During the nesting season, forest rangers patrol the beaches at night, carefully relocating eggs to protected incubation areas to shield them from tides, predators, and human interference. Given that turtles are highly sensitive to noise and white light, all ranger activities are conducted in complete darkness using specialized lighting.
To regulate the sex ratio of hatchlings, which is influenced by temperature, half of the eggs are placed in sunlit trays, while the others are covered with shaded nets to mimic natural conditions. This artificial incubation process has significantly improved hatching success rates, with over 1,000 nests protected annually and an 80% hatch success rate.
Through these ongoing efforts, Con Dao has become one of the last strongholds for Vietnam’s endangered sea turtles, offering visitors a rare chance to witness one of nature’s most incredible phenomena—the hatching of baby turtles and their first journey to the ocean.
Types of turtles on Con Dao
Con Dao is home to two main species of sea turtles that come to nest on its beaches: the green sea turtle and the olive ridley sea turtle. Both species are classified as endangered and play a critical role in maintaining the health of marine ecosystems. These turtles are part of the island’s delicate biodiversity and are carefully protected by Con Dao National Park’s conservation programs.
Green Sea Turtle
The green sea turtle (Chelonia mydas) is the most common species found on Con Dao and is recognizable by its smooth, heart-shaped shell, which can range in color from olive to dark brown. These turtles can grow up to 1.5 meters (5 feet) in length and weigh up to 200 kilograms (440 pounds). They are known for their incredible migrations, traveling thousands of kilometers between feeding grounds and nesting sites.
Green sea turtles are herbivores, feeding primarily on seagrass and algae, which gives their fat a greenish tint—hence their name. They can live up to 70-80 years in the wild and often return to the same beach where they were born to lay their eggs. Each nesting season, a female green sea turtle may lay between 80 and 120 eggs per nest and can nest multiple times during a single season.
Olive Ridley Sea Turtle
The olive ridley sea turtle (Lepidochelys olivacea) is smaller than the green sea turtle, with adults typically measuring 60 to 70 centimeters (2-2.5 feet) in length and weighing around 35 to 50 kilograms (75-110 pounds). They are named after their olive-colored, slightly domed shell. Olive ridley turtles are known for their unique nesting behavior called “arribada”, where thousands of females come ashore at the same time to lay eggs, although this phenomenon is less common in Con Dao.
These turtles are omnivorous, feeding on a variety of marine creatures, including jellyfish, crabs, and shrimp. Like green sea turtles, they are long-lived and can reach an age of 50 years or more. Olive ridley turtles typically lay between 80 and 100 eggs per nest and may also nest multiple times in one season.
Best time to see the turtles
Con Dao offers two main opportunities to witness the fascinating life cycle of sea turtles:
- April to October: This is the nesting season when mother turtles come ashore to lay their eggs. During these months, visitors have a chance to observe these incredible creatures as they dig nests and lay their eggs under the cover of night.
- May to December: This period marks the hatching season, where baby turtles emerge from their nests and make their way to the ocean. Con Dao National Park organizes releases of baby turtles, allowing visitors to witness this unforgettable moment.
For the best experience, plan your visit during the peak months of May to September, when both nesting and hatching activities are most frequent.
Where to see the turtles on Con Dao
Sea turtles nest on several beaches across Con Dao’s islands, but some locations attract significantly more turtles than others. Bay Canh Island is the most important nesting site, accounting for nearly 80% of sea turtle nesting activity in Con Dao. Other key nesting beaches include Cau Islet, Tre Lon Islet, Tai Islet, and Duong Beach. These beaches provide ideal conditions for nesting, with soft sand and minimal human disturbance.
Among all the nesting sites, only one beach allows nighttime access for visitors who want to witness mother turtles laying eggs. The rest are carefully protected by Con Dao National Park, with strict conservation measures in place to ensure the safety of both nesting turtles and hatchlings.
Turtle hatching and releasing tours on Con Dao
One of the most unforgettable experiences on Con Dao is witnessing sea turtles nesting or releasing baby turtles into the ocean. Con Dao National Park rangers organize tours that allow visitors to observe these incredible moments while ensuring the turtles remain protected. There are also options to combine this with snorkeling or trekking.
Watching mother turtles lay eggs (Night tour)
At night, mother turtles come ashore on Bay Canh Island—the main nesting site—to lay their eggs. The tour is guided by park rangers who ensure minimal disturbance, as turtles are extremely sensitive to noise and light. Visitors must wait quietly until a turtle arrives, at which point the rangers provide a close-up view of the nesting process. Each turtle lays between 80 to 120 eggs, which are then carefully covered before the mother returns to the sea. Due to the unpredictability of nature, sightings are not guaranteed, but during peak nesting season from May to September, the chances are high.
Releasing baby turtles (Morning tour)
The early morning turtle release is one of the most popular activities in Con Dao. After an incubation period of around 60 days, baby turtles hatch and are ready to be released back into the ocean. Visitors are given a basket of hatchlings and guided by rangers on how to safely send them off to their new life in the sea. The release must take place early in the morning before 8:00 AM to protect the hatchlings from predators and the heat of the sun. Since the hatching process is carefully monitored, this tour is more predictable compared to the night nesting tour.
Private turtle releases at Six Senses Con Dao
For those staying at Six Senses Con Dao, the resort offers a complimentary private turtle release experience. Their on-site turtle incubation center, in partnership with Con Dao National Park, protects eggs from threats like poaching. Guests have the opportunity to witness and participate in the ethical release of baby turtles directly from the resort’s beach. The hatching success rate at this center is exceptionally high, often reaching over 90%, making it a unique and responsible way to experience turtle conservation.
Diving with turtles in Con Dao
While Con Dao is known for its pristine coral reefs and rich marine life, spotting turtles while diving is a special experience. Hon Bay Canh is the most significant nesting site for sea turtles, however, it is not allowed for boats and diving. There are still chances to see turtles underwater during a dive in other areas. They are not extremely common, but lucky divers may encounter green sea turtles or hawksbill turtles swimming around the reefs.
The best chance to see turtles while diving is during the peak nesting season from May to October, when more turtles are in the surrounding waters. Some dive sites around Hon Bay Canh, Hon Cau, and Hon Tai offer occasional turtle sightings, but it is never guaranteed.
For more details on the best dive sites, diving seasons, and tips for underwater exploration, check out our full guide to diving in Con Dao.
