Baby Sea Turtles Hatching and Going to Ocean

Green sea turtle hatchling crossing beach, Laamu Atoll, Maldives. Image.
A green sea turtle hatchling crossing beach. © Andy Ball, MUI.

It's a lucky few that witness a sea turtle's first foray into the world. Seeing sea turtles make their way into the ocean can be transformational, life-altering, and an unforgettable experience. However, sea turtle hatchlings have a famously tricky start to life and only 1/1000 are estimated to survive to adulthood. As it is nesting season in many parts of the world, we thought it would be a good idea to shed some light on the difficulties new born turtles face, and the best practices to follow when witnessing a sea turtle hatching experience.

Green Turtle Mama Coming Back To Nest

A green sea turtle photographed nesting at dawn at Six Senses Laamu.

Nesting green sea turtles return to the same area where they themselves hatched to lay their eggs. These cold-blooded reptiles will mate off-shore, with the male hanging onto the females back while the female is responsible for coming up for air so they can breathe.

A nesting green sea turtle will wait for the cover of the darkness before making her way up the beach, using her front flippers to pull herself up. She will move up towards the vegetation line and dig herself a body pit. Once she is nice and comfortable, she will start digging a deeper egg chamber with her rear flippers.

A green turtle mama laying her eggs deep in the sand. © Beth Faulkner

Sea turtles lay their eggs deep in the sand to protect them from potential predators and also to ensure that the conditions of the nest is appropriate for the development of her eggs. As the eggs starts developing soon after they are laid, any disturbance can affect the success of the turtles hatching. One key influence on the development of the turtle egg is the temperature of the nest, which will determine the sex of the turtle. Warmer temperatures produce female turtles, cooler temperatures produce males. The sex ratio of the nest can vary, because some may be further down and therefore cooler. A nest can have between 100-200 eggs.

Freshly laid green turtle nest with tracks, Kuredu, Lhaviyani Atoll, Mladives. Image.
A freshly laid green turtle nest on Kuredu Island in the Maldives.

Turtles can nest multiple times during the nesting period – sometimes as often as eight times! This is to give as many of her offspring a chance to survive as possible. Females usually nest every two weeks, giving her plenty of time to recover in between. Once she is done, she will migrate back to her foraging grounds, leaving her babies to fend for themselves.

Hatchlings Emerge From The Nest

Green turtle hatching Maldives
Green sea turtle hatchlings emerging from the nest, Maldives © Chiara Fumagalli

After an incubation period of roughly two months, young turtles hatch in the sand and instinctively start digging their way up.

Hatchlings use a temporary egg tooth – 'caruncle' – to break through their egg shell. It can take them up to three days to emerge from the nest. The movement of little flippers kicking down sand can stimulate the rest of the group to start digging too. Together, they move and rest as one – taking naps in between so they don't tire themselves out. They usually leave the nest when it's cool outside to avoid getting overheated or sun-burnt. Hatchlings have been observed resting right at the surface of the nest, waiting for the cover of the darkness before they leave the safety their mother has provided for them.

Green turtle hatchlings emerging from the nest, Laamu Atoll, Maldives. Image.
A green sea turtle hatching event in Maldives shows how the hatchlings group together.

Baby Sea Turtles' Dangerous Journey To The Sea

Baby turtles are a source of food for all kinds of animals – crabs, birds, sharks, and even fish take their shot at these soft-shelled creatures. To increase their chances of survival, they leave for the ocean together at night. Navigating by following the light of the moon on the ocean's surface, sea turtles move towards the horizon while picking up cues from the beach which will later help them find their way back to nest. It's advisable to stay at a safe distance to avoid trampling the baby turtles. It is also best to allow them to make their way to the ocean without touching or handling them.

Green sea turtle hatcling swimming in the sea, Maldives. Image.
A green sea turtle hatchling swimming in the sea. © Leanna Crowley, MUI.

Once they're in the water, they'll kick with the might of their tiny flippers until they get to the open sea. Here they stay protected from most predators until their shells harden and they grow to a less vulnerable size. Being out in the ocean helps baby turtles to develop their lungs, strengthen their muscles, and learn to properly dive and swim. Turtles have been doing this for MILLIONS of years – so it's a breeding strategy that works and helps sustain the turtle population.

Where it gets tricky is human disturbances, which can make this particularly challenging for sea turtles. Artificial forms of light can leave them disoriented and confused, making them lose their way. Holding back baby turtles when they hatch causes them use up their energy – which they have a limited amount of when they hatch. This will make their swim into the deep ocean even tougher. Trash and rubbish on the beach can hinder their path, not allowing them to access the ocean.

How We Keep Sea Turtle Nests Safe

A protected sea turle nest at Six Senses Laamu, Maldives. Image.
A protected sea turtle nest at Six Senses Laamu, Maldives, is monitored by a NestWatch Camera from Reolink.

When monitoring turtle nests, our aim is to keep it as natural as possible. We monitor our beaches for turtle nesting tracks, which helps us identify the nest location. We mark the nests with a sign so that people will know not to walk across it or dig it up accidentally, as it is usually close to the vegetation line. After 50 days of incubation, we set up a fabric enclosure around the nest which opens towards the sea to prevent any hatchlings from running into the vegetation or the roads. It's also a visual cue to keep an appropriate distance from the nest.

Best Practices to Follow During a Sea Turtle Hatching Event

A green sea turtle hatchling enters the water, Laamu Atoll, Maldives.
A green turtle hatchling enters the water. © Leanna Crowley, MUI.

It is estimated that only 1/1000 hatchlings survive till adulthood. The first steps of their journey can be the most difficult, If you are lucky enough to witness a sea turtle hatching event, make sure you follow these best practices to allow the hatchlings to reach the sea safely:

What To Do If You Witness A Sea Turtle Nest Hatch

  1. Keep your distance.
  2. Turn off any lights you are using.
  3. Crouch down low.
  4. Be quiet.
  5. Stay behind or to the side of the hatchlings.
  6. If the hatchlings head in the wrong direction, try to create natural barriers like piles of sand to encourage them to go the other way towards the ocean.

What Not To Do Around Sea Turtle Hatchlings

  1. No handling or picking up of turtles. Sea turtles imprint on the beach where they're born, picking up cues as they run down the sand. We want to make sure they come back to the same beach. We also want to avoid getting any harmful bacteria from human hands on them. In addition, it is worth noting that it is llegal to handle hatchlings in the Maldives and many other places.
  2. No interferences or buckets. Sea turtles come out when it's the right time for them, and we have to trust their process. It's best to leave them to go into the sea when they hatch – even when they hatch during the day. Because they have only a limited amount of energy when they hatch, they can tire themselves out trying to get out of the bucket if you place them in one.
  3. No bright lights or flash photography: If you absolutely must use lights during a sea turtle hatching (or nesting) event, use red lights rather than white or yellow. Make sure to point the light behind the turtles, so the hatchlings will follow the direction the light is coming from. Lights can easily disorientate hatchlings, so keep the flash off on your camera or phone before you start filming or photographing them.
  4. No crowding or stepping on turtles. Clear a path for the hatchlings to run into the sea, and do not to step over it. If they head towards you, step back and give them space! Sometimes a hatchling can end up crawling over someone if they stand too close, which can causes a knee-jerk reaction that could harm the hatchling. Be as calm as possible, and do not move around too much when watching a turtle hatching.

With these tips in mind, we hope you're able to enjoy watching hatchlings safely make their way into the sea. Even though these miraculous little creatures are more resilient than they look, we can ensure they stay around for millions more years by keeping these best practices in mind.

Download ORP's Sea Turtle Code of Conduct

Find The Answers To All Your Sea Turtle Questions

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Sea Turtles FAQ

Male hawksbill popping head above surface for air, Maldives. Image.
Marvin, male hawksbill, coming up for a breathe, Maldives.

Sea turtles can hold their breath for several hours, depending on their level of activity.

If they are sleeping, they can remain underwater for several hours. In cold water during winter, when they are effectively hibernating, they can hold their breath for up to 7 hours. This involves very little movement.

Although turtles can hold their breath for 45 minutes to one hour during routine activity, they normally dive for 4-5 minutes and surfaces to breathe for a few seconds in between dives.

However, a stressed turtle, entangled in a ghost net for instance, quickly uses up oxygen stored within its body and may drown within minutes if it cannot reach the surface.

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References:

  • Hays GC, Akesson S, Broderick AC, Glen F, Godley BJ, Luschi P, Martin C, Metcalfe JD & Papi F 2001. The diving behaviour of green turtles undertaking oceanic migration to and from Ascension Island: dive durations, dive profiles and depth distribution. Journal of Experimental Biology 204: 4093-4098.
  • Hays GC, Hochscheid S, Broderick AC, Godley BJ & Metcalfe JD 2000. Diving behaviour of green turtles: dive depth, dive duration and activity levels. Marine Ecology Progress Series 208: 297-298.
  • Hochscheid S, Bentivegna F & Hays GC 2005. First records of dive durations for a hibernating sea turtle. Biology Letters 1: 82-86.
  • Lutz PL and Musik JA (eds.) 1996. The Biology of Sea Turtles Volume I. CRC Press.

The actual documentation of a sea turtle's age in the wild is difficult or nearly impossible. Individual turtles can be tracked for a shorter time of six month to three years with the help of satellite transmitters. Longterm studies rely on capture-recapture principle, just like our turtle photo id project. Each photo of a turtle represents a recapture event documenting that the individual is still alive.

A study of nesting green turtles in Hawaii observed female turtles returning to nest for up to 38 years after they were first identified. Assuming the average age at first nesting activity of 24 years, this would show that green turtles can live to up to at least 62 years.

Similar estimates have been made for loggerhead turtles.

References:

  • Dodd C 1988. Synopsis of the biological data on the loggerhead sea turtle. Ecology 88.
  • Humburg IH and Balazs GH 2014. Forty Years of Research: Recovery Records of Green Turtles Observed or Originally Tagged at French Frigate Shoals in Northwestern Hawaiian Islands, 1973-2013. NOAA Technical Memorandum NMFS-PIFSC-40.

When sea turtles are juveniles, it is very difficult to tell their sex by eye as they do not differ externally. However, after reaching sexual maturity male sea turtles develop a long tail, which houses the reproductive organ. The tail may extend past the hind flippers.

Female turtles have a short tail, which generally doesn't extend more than 10 cm (4 inches) past the edge of the carapace. Male sea turtles (except leatherbacks) have elongated, curved claws on their front flippers to help them grasp the female when mating.

The sex of a sea turtle embryo is determined by the temperature of the sand: warm temperatures result in more females while cooler temperatures result in more males.

The olive and Kemp's ridley sea turtles are the smallest species, growing only to about 70 cm (just over 2 feet) in shell length and weighing up to 45 kg (100 lbs). Leatherbacks are the largest sea turtles. On average leatherbacks measure 1.5 – 2m (4-6 ft) long and weigh 300 – 500 kg (660 to 1,100 lbs). The largest leatherback ever recorded was 2,56 m (8.4 ft) long and weighed 916 kg (2,019 lbs) !

Kemp's Ridley

Nesting female kemp's ridley turtle, nicknamed "Mij", laying 116 eggs on Galveston's East Beach. ©Ron Wooten, Wildscreen Exchange.

55.6-66.0 cm carapace length, weight range of 25-54 kg for nesting females.

References:

  • Marquez-M R 1994. Synopsis of Biological Data on the Kemp's Ridley Turtle, Lepidochelys kempi (Garman, 1880). NOAA Technical Memorandum NMFS-SEFSC-343.

Olive Ridley

Female Oliver ridley turtle nesting on the beach during arribada
Nesting female olive ridley turtle ©Susie Gibson.

Curved carapace length 52.5-80.0 cm, weight less than 50 kg (average 35.7 kg) for nesting females.

References:

  • Qureshi M 2006. Sea turtles in Pakistan. In: Shanker K and Choudhury BC (Eds.). Marine Turtles of the Indian Sub- continent. Heydarabad: India Universities Press, pp. 217–224.Reichart HA 1993.
  • Reichart HA 1993. Synopsis of biological data on the olive ridley sea turtle Lepidochelys olivacea (Eschscholtz 1829) in the western Atlantic. NOAA Technical Memorandum NMFS-SEFSC-336.

Hawksbills

Adult male hawksbill turtle swimming in the blue, Maldives. Image
Adult male hawksbill, Maldives.

Nesting females reported between 53.3 and 95.5 cm carapace length, with weight between 27.2 and 86.2 kg.

References:

  • Witzell WN 1983. Synopsis of biological data on the hawksbill turtle, Eretmochelys imbricata (Linnaeus, 1766). No. 137. Food & Agriculture Org.

Green turtles

Adult green turtles mating, Malsdives. Image.
Adult green turtles mating, Maldives.

Nesting green females reported curved carapace length 75-134 cm, weight (after egg deposition) 45-250 kg (!).

References:

  • Hirth HF 1997. Synopsis of the Biological Data on the Green Turtle Chelonia mydas (Linnaeus, 1758). Vol. 2. Fish and Wildlife Service, US Department of the Interior.

Flatbacks

Ones study (Ref. 1) found nesting females have a mean curved carapace length 86.3 cm, and mean weight of 67.4 kg. Another study (Ref. 2) found flatbacks to be between 87.5-96.5 cm.

References:

  • Schäuble C, Kennett R and Winderlich S 2006. Flatback Turtle (Natator depressus) nesting at Field Island, Kakadu National Park, Northern Territory, Australia, 1990-2001. Chelonian Conservation and Biology 5: 188-194.
  • Limpus CJ 1971. The Flatback Turtle, Chelonia depressa Garman in Southeast Queensland, Australia. Herpetologica 27: 431-446.

Loggerheads

Adult female loggerhead, Oman.

Adult loggerhead turtles measure between 65 and 115 cm in curved carapace length and typically weigh between 40 and 180 kg. The largest recorded loggerhead weighed 545 kg and measured 213 cm in presumed total body length. On average, nesting, and therefore adult, female loggerheads have a curved carapace length of 65.1-114.9 cm and weigh between 40.0 and 180.7 kg. Males fall into the same size range (79.0-104.0 cm curved carapace length).

References:

  • Brongersma LD 1972. European Atlantic turtles. Zoologische Verhandlingen 121, Leiden.
  • Dodd C 1988. Synopsis of the biological data on the loggerhead sea turtle. Ecology 88: 1-119.
  • Ernst CH and Lovich JE 2009. Turtles of the United States and Canada, 2nd edition. John Hopkins University Press.

Leatherbacks

Leatherback Turtle, Claudia Lombard, USFWS
Adult leatherback turtle ©Claudia Lombard, USFWS.

143.8-169.5 cm curved carapace length, weight 259-506 kg recorded for nesting females all around the world. Largest ever recorded specimen was found dead on a beach on the coast of Wales. The adult male turtle weighed 916 kg and its shell was 256.5 cm long. An autopsy revealed that it had drowned.

References:

  • Eckert KL and Luginbuhl C 1988. Death of a Giant. Marine Turtle Newsletter 43: 2-3.
  • Eckert KL, Wallace BP, Frazier JG, Eckert SA and Pritchard PCH 2012. Synopsis of the Biological Data on the Leatherback Sea Turtle (Dermochelys coriacea). Biological Technical Publication BTP-R4015-2012, US Fish & Wildlife Service.

Sea turtles eat a broad range of diets. Each sea turtle species has uniquely evolved to different environments and available food depending. Sea turtles therefore play a vital role in ocean ecosystems, affecting the diversity and function of ocean habitats by what they eat. Common for them all is that they all lack theeth!

The specific diet of Each sea turtle species

Flatbacks

Goniobranchus gleniei nudibranch, Maldives. Image.
Nudibranches, or sea slugs, are a favourite of flatbacks. This is a Goniobranchus gleniei. ©Stephanie Köhnk.

Flatbacks are mainly carnivorous, feeding in shallow waters on soft bottoms. Little is known about this species' diet throughout their lifetime, but juveniles and adults are known to eat snails, jellyfish, corals and other soft bodied invertebrates.

Greens

Green turtle eating seagrass, Maldives. Image.
Green turtle eating seagrass, Maldives.

Green turtles are vegetarian and prefer sea grasses, sea weeds and algae as adults, however, green turtle hatchlings are omnivorous, eating jellyfish, snails, crabs, and shrimp.

Hawksbills

Hawksbill sea turtle foraging on a reef, Baa Atoll, Maldives. Image.
Hawksbill turtle foraging on a reef, Baa Atoll, Maldives.

Hawksbills have a bird-like beak that is used to cut through soft coral, anemones and sea sponges.

Kemp's Ridleys

Trapezia lutea orange coral crab. Image
Coral crabs (Trapezia lutea) form part of the kemp's ridley diet. ©Stephanie Köhnk .

Kemp's ridleys are omnivores at the beginning of their lives, feeding on seaweed and small creatures like crabs and snails. As adults, Kemp's ridleys look for food on the seabed, feeding on crustaceans, fish, molluscs, squids and jellyfish.

Leatherbacks

Jelly fish, Kenya. Image
Jelly fish in Kenya. ©Joana Hancock.

Loggerheads

Loggerhead sea turtles eat a variety of prey depending on their life stage. Image.
A juvenile loggerhead feeding on tuna.

Loggerheads are carnivores, feeding on a variety of prey depending on their life stage but mainly on hard-shelled organisms such as lobsters, crustaceans, and fish.

Olive Ridleys

Turtle patient Azura eating lobster. Image.
Turtle patient Azura, an olive ridley, eating lobster.

Olive ridleys are omnivorous, mostly eating jellyfish, snails, crabs, and shrimp but they will occasionally eat algae and seaweed as well.

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Baby Sea Turtles Hatching and Going to Ocean

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