How Many Eggs Does A Sea Turtle Lay?
fact checked & review by
Dr. Partho Kumar Shaha
Veterinarian (DVM)
The information is current and up-to-date in accordance with the latest veterinarian research.
Most sea turtle species have a ritual of community nesting. Thousands of gravid marine turtles gather on shores and nest together. Do you know how many eggs a sea turtle lays? Or what happens to the eggs after the mother turtle leaves the nest?
Sea turtles lay 40 to 200 eggs at one time. While the Hawksbill sea turtles deposit the largest clutches, the flatback sea turtles lay roughly 50 eggs at a time. These turtles deposit 2 to 6 times in one nesting season.
Give the following article a read if you find the lifecycle of a sea turtle interesting. I will shed light specifically on the eggs and everything about them.
How Many Eggs Does A Sea Turtle Lay?
Do you know how many eggs the aquatic, semi-aquatic, and land turtles lay? The female giant Asian softshell turtle, box turtle, map turtle, snapping turtle deposits, 24 to 70, 8 to 9, 10 to 12, and 20 to 40 eggs, respectively, in a clutch.
Do you know how many eggs the gravid sea turtle lays? The reports say a female sea turtle can lay 40 to 200 eggs in a clutch.
Yes, you have read it right. The sea turtles can deposit up to 200 eggs, and in rare cases, the clutch contains more than 200 eggs. Hence, the clutch size of the marine turtles is gigantic compared to the aquatic and semi-aquatic turtles.
The clutch size of sea turtle eggs depends on the species. There are 7 subspecies of sea turtles, each with different physical appearances and characteristics. Do you feel confused while identifying the marine turtles? Here is the easiest trick to determine the turtle species.
Sea Turtle Clutch Size
Sea Turtle | Clutch Size | Additional Information |
---|---|---|
Leatherback Sea Turtle | 80 to 110 eggs | The gravid leatherback sea turtle lays 3 to 10 clutches per season. The success rate of the clutch hatching is 50%. |
Loggerhead Sea Turtle | 110 to 130 eggs | Loggerhead sea turtles nest multiple times in each season. The eggs have a 60 to 85% success rate to make it out alive. |
Green Sea Turtle | 40 to 120 | The record clutch size of a green sea turtle is 219 eggs. These turtles nest 1 to 4 times each season taking a 2 weeks gap in between. |
Hawksbill Sea Turtle | 140 to 200 eggs | Hawksbill sea turtles have the largest clutches among all the sea turtle subspecies. The gravid turtle lays 4.5 clutches in one season. According to a report, the hatching success rate of hawksbill sea turtles is 58.3%. |
Kemp’s Ridley Sea Turtle | 100 to 120 egg | Kemp’s ridleys sea turtles nest 2.5 times each season, and one clutch contains more than 100 eggs. |
Olive Ridley Sea Turtle | 90 to 130 eggs | The Olive ridleys sea turtle lays 1 to 3 clutch per season with a hatching success rate of 78%. |
Flatback Sea Turtle | 50 eggs | The flatback sea turtles are small and deposit the smallest clutch among all the marine turtle subspecies. These turtles might nest multiple times in one season. |
How Many Eggs Does A Normal Sea Turtle Lay?
Generally, the sea turtle clutches contain more or less than 100 eggs. Some subspecies, like flatback sea turtles, lay 50 eggs per clutch, whereas the hawksbill sea turtles might deposit up to 200 eggs at a time.
Sea turtles lay the largest egg clutches among all turtle species. On average, a healthy gravid sea turtle deposits around 100 eggs at a time.
Each season the turtle lays multiple clutches taking a two-week gap in between. It means the mother turtle deposits hundreds of eggs each year.
There is no way of predicting the clutch size of a gravid sea turtle. Experts used to believe that the body size of the female turtle decides the egg quantity. Recent studies have proved this theory wrong.
Researchers claim there is no direct link between sea turtle physique and clutch size. They have observed an age pattern in this manner. The team suggests that the sea turtles lay more eggs with the growing age and the egg size has a correlation to the female body size.
So, if a green sea turtle deposits 40 eggs in one season and 100 eggs in another, it is absolutely normal. The turtle is still healthy and following the biological rules.
How Many Sea Turtle Eggs Survive?
The egg survival rate lies between 50 to 85%. Even though most hatchlings make it out of the nest, 7.6% of these babies can not reach the water.
Sea turtles have 7 subspecies available right now. Unfortunately, most subspecies are already endangered, and others are threatened. The low rate of egg survival might be one of the reasons behind this endangerment.
A mother sea turtle lays 40 to 200 eggs, depending on the age and species.
But not all the eggs enjoy a happy ending. Some eggs get damaged right away, while the female turtle deposits them.
Again, the nesting temperature, humidity level, pressure, and other factors might affect the healthy growth of the eggs. Sometimes, the nesting chamber environment ruins the egg yolks.
Even with all these challenges, 50 to 85% of the eggs hatch, and the babies get out of the chamber. Unfortunately, a significant number of the hatchlings, approximately 7.6%, can not reach the water. The vulnerable state, improper guidance, predator attack, etc., are responsible for this loss.
Predators often dig up the nest and feast on the eggs. As a result, hundreds of sea turtle eggs get lost every year. Sadly, the animals are not the only ones to blame here.
Many coastal tribes collect these eggs and use them as nutritious food. Even different restaurants serve sea turtle eggs as their exquisite menu.
For all of these reasons, the survival rate of sea turtle eggs is nothing to brag about. Many hatchlings who make it to the sea can not make it alive for even a few years. A study says that only 1 in 1000 sea turtle babies grow to adulthood. Others fall victim to the open ocean and sea predators.
Preserving the eggs is a must to increase the survival rate of sea turtles. Thanks to the wildlife and marine turtle associations all around the world. These organizations have come forward and taken action to save the sea turtle species.
Digging up sea turtle eggs, eating, harming, or taking them home is a punishable crime now. Not only that, petting a sea turtle or even touching the creatures is a third-degree felony in many states. Learn more about this law and enforcement from this link.
Do Sea Turtles Lay Eggs Every Year?
Female sea turtles lay eggs every 2 to 4 years, except the Kemp’s Ridleys sea turtles. The species supposedly mate and nest each year without any gap.
Carrying eggs is a challenging phase for marine turtles. They might face complications during the gestation period. On the top, looking for nesting spots is a tiring task for the gravid sea turtles.
Walking on the beaches with hundreds of eggs inside on flippers is not a cup of tea. Many turtles give up in the middle and attempt to lay eggs in water. Even many continue their life without egg deposition.
Such an event is called a false crawl, which can be dangerous for the marine turtle’s health.
So, the female sea turtles have to store energy for the whole breeding and nesting period. The turtles rest for 10 to 15 days to heal after depositing eggs. Then they return to their feeding zone to prepare for the next season.
A 2 to 4 years of gap between the nesting season sounds fair and healthy considering all these hassles. However, subspecies like Kemp’s Ridleys might not take this long rest and nest the successive year.
While the male sea turtles mate every year, the females do it occasionally. A female sea turtle can carry the sperms after copulation for years without fertilizing them. The fertilization of the sperm and eggs occurs when the body is prepared to carry out the task.
Get a visual infographic on the sea turtle life cycle from this article.
Do Sea Turtles Reunite With Mother?
Sadly, the sea turtle hatchlings grow up without any mother. The gravid turtle comes to the beach to nest and crawls back to the ocean once she deposits her eggs. After that period, she never returns to the nest or looks for her babies ever in her life.
I know it sounds harsh to grow up without a mother. But sea turtles are biologically compatible with the event. The mother turtle never comes looking for her children, and similarly, the babies never miss their mother. Experts suggest that the mother turtles return to their feeding areas after the egg deposition.
The whole clutch of eggs does not hatch overnight. Once the time comes, one or two hatchlings come out of the eggs. These babies make a distinct noise while breaking the eggshells as a part of their communication. The sound also works as an indication for all the siblings to break down the shell.
The mother sea turtles do an excellent job covering up the nesting chamber with sand so that it goes unnoticed. So, coming to the surface is not an easy task for babies.
Hatchlings collectively push up the mountain of sands to make a way out. It probably takes 3 to 5 days for these newborns to move the nest cover.
Once the sea turtle hatchlings are on the land, they run towards the ocean. On moon nights, the little turtles use the moonlight as their guide. On other days, the babies follow the wave sound and make their way to their new home.
A report says about 7.6% of hatched sea turtles can not even reach the ocean and die before that. Again, only 1 out of 1000 hatchlings can enjoy their adult years. So, survival is not so easy for these turtles.
The first days are even more challenging for newborn sea turtle babies because of their vulnerability. But still, the babies do not feel the necessity for their mothers, not for once.
Do Sea Turtles Lay Eggs At Night?
Sea turtles choose the night for egg deposition as the nighttime is cooler and less crowded. The gravid turtles require 4 to 7 hours to lay all the eggs. A few species might deposit eggs during the day.
Laying eggs is a time-consuming process. It takes roughly 45 minutes to 7 hours for the gravid turtle to deposit a whole clutch.
The sea turtles choose nighttime for the course as it is less hot and the risk of heatstroke is zero. Also, the night hours are less distracting, and the turtles can deposit eggs uninterrupted. Generally, the mother turtles enter into a semi-unconscious state while laying eggs. So, they might spend the night in the nest and return to the ocean in the dawn.
Some marine subspecies might show an exception to this night rule. The Hawksbill sea turtle and Olive Ridley sea turtle are two marine species that deposit eggs during the daytime.
Do Sea Turtles Go Back To Their Eggs?
A mother sea turtle never comes back to her eggs. Once she completes the deposition, she goes back to her ocean life. Experts suggest that the gravid turtle returns to her feeding area for healing and preparing for the next mating season.
Female sea turtles carry eggs a few weeks after a successful mating. The turtles can even preserve the sperms for years and then fertilize the eggs. The gravid turtle starts looking for a suitable nesting place on the shore once she is ready to deposit the eggs.
The search does not always go as planned. Dragging the body all the way to the shore with flat flippers is challenging for the gravid marine turtles. Many mothers give up and return to the sea.
The gravid marine turtles prefer night time for nesting. Olive Ridley and Hawksbill sea turtles are two exceptions as these two subspecies lay their eggs during broad daylight. The nesting period might take hours.
Once the mother turtles have finished depositing the clutch, they will peck down the chamber with sand and dirt. They are good at this task and cover their tracks wonderfully. The humans and predators barely notice the egg chamber. The turtles are now free and crawl back to the sea again.
Most gravid sea turtles lay more than one egg clutch in one season, giving gaps of a week or two. Not once do the mothers return to the nest or look for their babies.
How Many Times A Year Does A Sea Turtle Lay Eggs?
Sea turtles lay eggs during one season but in many clutches. Every year, the gravid turtle nests 2 to 6 times, and each time she deposits 40 to 200 eggs. The turtle takes a two weeks break between laying the clutches.
The marine turtles deposit large clutches with around 100 eggs on average. The fun part is these turtles lay more than one clutch in a year.
Generally, the clutch numbers lay between 2 to 6, depending on the subspecies. But the record number of egg clutches deposited by any gravid sea turtle is 8.
The female sea turtles do not nest every year. Carrying and laying eggs is a challenging task for these turtles. So, they take a 2 to a 4-year gap between two nesting seasons. The resting period can go up to 9 years.
Sea turtles do not lay eggs each year, but it does not mean that they do not mate. The female turtles can carry the sperm without fertilizing them for years.
How Many Eggs Do Sea Turtles Lay In A Lifetime?
Now that you know how many eggs a sea turtle can lay in a single clutch, you are probably wondering how many eggs a sea turtle lay in a lifetime. On average, sea turtles lay 1000 to 2300 eggs in a lifetime. But the number of eggs depends on the specie of the turtle and other factors. We have to consider these factors:
- Number of clutches and eggs in a season
- How often do sea turtles lay eggs?
- How long do sea turtles live?
Number of Eggs in a Season
By now, you know sea turtles can lay 2 to 10 clutches every season. Depending on the species of turtles, each clutch can have 40 to 200 eggs! However, the number of eggs in each clutch may vary.
For example, typically, leatherbacks lay 3 to 6 clutches in a single season. Each clutch can have 80 to 110 eggs. A leatherback can lay 350 to 600 eggs in a single season. On the other hand, green sea turtles lay 40 to 120 eggs in a single clutch. They lay 1 to 4 clutches every season. So, they may lay 100 to 400 eggs in total in a season.
You may think sea turtles can lay thousands of eggs in their lifetime if they lay eggs at this rate. But that is not the case. Let’s discuss more to understand.
Sexual Maturity of Sea Turtles
Sea turtles lay eggs when they become sexually mature. When sea turtles become sexually mature, depending on their species and geographical location. While some sea turtles become sexually mature as early as 8 to 10 years, others may take up to 30 years or more. Here are the ages of sexual maturation of different sea turtle species:
- Leatherbacks: 8 to 12 years
- Olive Ridley Sea turtles: 10 to 15 years
- Hawksbill: 15 to 30 years
- Loggerheads: 17 to 33 years
- Green sea turtles: 20 to 50 years.
When they become sexually mature, they travel back to the seashore where they were born. There, sexually mature male and female sea turtles mate to reproduce. Then the female turtles lay eggs on the shore.
How Often Sea Turtles Lay Eggs
Now, here is an interesting fact. Sexually mature sea turtles do not lay eggs every year. Mating and laying eggs can have a toiling impact on female turtles. So, they rest for a few years before mating and laying eggs again. Most sea turtle species nest every 2 to 3 years.
The Lifespan of Sea Turtles
The life span of a sea turtle is another crucial factor that determines how many eggs a sea turtle lays in a lifetime. For example, green sea turtles can live 80 to 100 years but become sexually mature much later in life. Then loggerheads live about 47 to 67 years and become sexually mature at 17 to 33 years.
Thus, sea turtles actually lay eggs for a certain period of time in their life. Still, they manage to lay 1000 to 2300 eggs in a lifetime.
How Old Are Sea Turtles When They Lay Eggs?
Sea turtles mature very late, at the age of 10 to 50. But these turtles nest for the next 30 years or even more, laying more than 2000 eggs.
Marine turtles live a longer life than aquatic and semi-aquatic turtles. They also enjoy a slightly different biological mechanism balanced for the open ocean. Maybe for these reasons, the sea turtles attain sexuality at a late age.
While most turtle species reach maturity between 5 to 15 years, marine turtles gain sexual freedom at the age of 10 to 50. But this late start barely affects their reproduction function.
The male sea turtles enjoy mating every year with several partners. Again, female turtles can nest for more than 80 years. The gravid turtle lays 2 to 6 clutches of around 40 to 200 eggs every year.
Why Do Female Sea Turtles Lay More Than 1000 Eggs?
One adult sea turtle might lay 1900 to 2300 eggs in her lifetime. The survival rate of the eggs is low. So, the bulk ratio of egg deposition ensures that there will be no chaos in the ocean population and bio-diversity.
See, mother nature has her own way of evening out the imbalance, or at least she tries. For you, the marine turtle is another random creature of the sea. But on a bigger picture, this naive species has a significant role in balancing the world eco-system.
So, what would happen if all the sea turtles were extinct? The vegetation would lose nutrients, the food cycle of the ocean would take a hit, and finally, the whole bio-system in the sea would go out of track. As a result, we, the land dwellers, would face various consequences.
Sea turtles are already endangered species. A report says 1 out of 1000 hatchlings can reach adulthood, making the survival percentage 0.01%. Habitat loss, climate change, predator attacks, human-made traps, plastic dumps, turtle poaching, etc., are why this majestic species is on the way to extinction.
Marine turtles lay more than 1000 eggs in their lifetime to balance the loss and save the species from extinction. For most turtles, the number lies between 1900 to 2300. Not all these eggs hatch and get to live a long life, but the risk of extinction definitely narrows down.
Conclusion
Sea turtles lay 40 to 200 eggs, depending on the species. These turtles nest once every 2 to 4 years, and each time they deposit 2 to 6 clutches. According to statistics, a female marine turtle lays around 1900 to 2300 eggs in her lifetime.
About Author
Muntaseer Rahman started keeping pet turtles back in 2013. He also owns the largest Turtle & Tortoise Facebook community in Bangladesh. These days he is mostly active on Facebook.