24 Interesting Facts about Hawaiian Green Sea Turtles

Dan March 9, 2024

Hawaiian green sea turtles, known as “honu” in Hawaiian, are an iconic symbol of the Hawaiian Islands and play a significant role in the state’s marine ecosystems and cultural heritage. These graceful marine reptiles are named for their greenish coloration, which results from the algae they consume and the fat deposits beneath their shells.

Hawaiian green sea turtles are found throughout the waters of Hawaii, where they inhabit nearshore coral reefs, seagrass beds, and coastal areas. They are known for their distinctive behavior, including basking on beaches and rocks to regulate their body temperature and resting on the ocean floor during periods of inactivity.

The Hawaiian green sea turtle is a keystone species in Hawaii’s marine ecosystems, playing a crucial role in maintaining the health and balance of coral reefs and seagrass habitats. As herbivores, they graze on algae, helping to prevent overgrowth that can smother coral and compete with other marine organisms for space and resources.

In Hawaiian culture, green sea turtles hold great significance as symbols of longevity, wisdom, and protection. They are revered as ancestral guardians, or “aumakua,” believed to watch over and guide the Hawaiian people. Honu are often depicted in traditional Hawaiian art, stories, and chants, highlighting their cultural importance.

Despite their cultural and ecological significance, Hawaiian green sea turtles face various threats, including habitat degradation, pollution, entanglement in marine debris, and illegal poaching. Conservation efforts, such as habitat protection, marine debris cleanup, and public education, are essential for safeguarding the future of these beloved marine creatures and preserving their vital role in Hawaii’s marine ecosystems and cultural heritage.

It’s a good idea to look at these 24 interesting facts about Hawaiian green sea turtles to know more about them.

1. Ancient Species: Hawaiian green sea turtles, or “honu,” have been swimming in the ocean for over 150 million years, making them one of the oldest living species on Earth.
2. Protected Species: Hawaiian green sea turtles are protected under the Endangered Species Act and the Marine Mammal Protection Act, as their populations have declined due to overharvesting and habitat destruction.
3. Distinctive Coloration: Despite their name, Hawaiian green sea turtles’ shells can vary in color from shades of brown to olive, black, or gray, depending on their age and diet.
4. Large Size: Adult Hawaiian green sea turtles can weigh up to 400 pounds (181 kilograms) and measure over four feet (1.2 meters) in length, making them one of the largest species of sea turtle in the world.
5. Vegetarian Diet: Unlike other sea turtle species, Hawaiian green sea turtles are primarily herbivores, feeding on algae, seagrasses, and other marine vegetation found in shallow coastal waters.
6. Migration Patterns: Hawaiian green sea turtles undertake long-distance migrations between their foraging grounds in Hawaii and nesting beaches in the Northwestern Hawaiian Islands, traveling hundreds of miles each year.
7. Nesting Behavior: Female Hawaiian green sea turtles return to their natal beaches in the Northwestern Hawaiian Islands to lay their eggs, a process known as “natal homing.” They typically lay clutches of 100-200 eggs in shallow nests dug in the sand.
8. Slow Reproduction: Hawaiian green sea turtles have a slow reproductive rate, with females reaching sexual maturity at around 25-35 years of age and only nesting every 2-5 years.
9. Nesting Season: The nesting season for Hawaiian green sea turtles in the Northwestern Hawaiian Islands typically occurs between May and September, with peak nesting activity in June and July.
10. Temperature-dependent Sex Determination: The sex of Hawaiian green sea turtle hatchlings is determined by the temperature of the sand in which their eggs are incubated, with warmer temperatures producing females and cooler temperatures producing males.
11. Threats to Nesting Sites: Rising sea levels and coastal erosion threaten the nesting beaches of Hawaiian green sea turtles, reducing available nesting habitat and increasing the risk of nest inundation during storms.
12. Natural Predators: Hawaiian green sea turtle eggs and hatchlings face predation from a variety of natural predators, including ghost crabs, birds, and fish, which can significantly impact nesting success rates.
13. In-Water Predators: Adult Hawaiian green sea turtles have few natural predators, but sharks, crocodiles, and killer whales are known to occasionally prey on them, particularly during their vulnerable hatchling and juvenile stages.
14. Resting Behavior: Hawaiian green sea turtles exhibit a behavior known as “basking,” where they surface to rest or warm themselves in the sun, often seen on beaches or rocky outcrops along the coastline.
15. Long Lifespan: Hawaiian green sea turtles can live for several decades or even centuries, with some individuals known to exceed 80 years of age in the wild.
16. Scute Patterns: The distinctive patterns of scutes (scales) on the shells of Hawaiian green sea turtles are unique to each individual, similar to human fingerprints, and can be used for identification purposes.
17. Tagging Studies: Researchers use satellite and acoustic tags to track the movements and behavior of Hawaiian green sea turtles, providing valuable insights into their migratory patterns, foraging behavior, and habitat use.
18. Tourist Attractions: Hawaiian green sea turtles are popular attractions for tourists visiting Hawaii, with designated viewing areas and guidelines to ensure minimal disturbance to the animals and their habitats.
19. Conservation Success: Conservation efforts, including habitat protection, nesting beach monitoring, and public education, have helped to stabilize and increase Hawaiian green sea turtle populations in recent years.
20. Cultural Symbolism: Hawaiian green sea turtles hold significant cultural symbolism in Hawaiian mythology and folklore, representing wisdom, longevity, and protection as ancestral guardians, or “aumakua.”
21. State Reptile: In 1988, the Hawaiian green sea turtle was designated as the official state reptile of Hawaii, reflecting its cultural and ecological importance to the islands.
22. Marine Debris: Hawaiian green sea turtles are at risk of ingesting or becoming entangled in marine debris, such as plastic bags and fishing gear, which can cause injury or death.
23. Public Awareness: Public awareness campaigns, such as “Malama Honu,” encourage responsible behavior around Hawaiian green sea turtles, emphasizing the importance of keeping a safe distance and avoiding touching or feeding them.
24. Hope for the Future: Despite ongoing threats, continued conservation efforts, community engagement, and scientific research offer hope for the long-term survival and recovery of Hawaiian green sea turtles, ensuring their presence in Hawaii’s marine ecosystems for generations to come.

Hawaiian green sea turtles, or “honu,” stand as magnificent ambassadors of Hawaii’s marine ecosystems and cultural heritage. As ancient creatures that have inhabited the oceans for millions of years, they symbolize resilience, wisdom, and the interconnectedness of all life. Despite facing numerous threats, including habitat loss, pollution, and climate change, ongoing conservation efforts and public awareness initiatives offer hope for their continued survival and recovery. By fostering a deeper appreciation for these gentle giants and advocating for their protection, we can ensure that future generations have the privilege of encountering these majestic creatures in Hawaii’s crystal-clear waters. May the sight of a Hawaiian green sea turtle inspire us to cherish and protect the precious natural wonders of our planet for the benefit of all living beings.