Green Sea Turtles: 30-Year Wait For Mating?

Green sea turtles are fascinating creatures that inhabit tropical and subtropical waters worldwide. They are known for their vibrant shells and gentle nature, and have a reputation for being loyal and committed partners. But does this loyalty extend to lifelong monogamy? Well, not exactly. While green sea turtles do exhibit a certain level of fidelity, returning to the same mating grounds and seeking out familiar partners, they are not exclusive to one mate for their entire lives. They engage in multiple mating encounters, sometimes even with different partners during a single breeding season. This behaviour, known as polyandry, ensures genetic diversity and increases the chances of successful reproduction.

When it comes to sexual maturity, male green sea turtles reach this stage between the ages of 20 and 50, while females mature between 25 and 35 years. So, it can indeed take 30 years or more for some green sea turtles to reach the age of sexual maturity and begin mating.

Green sea turtles reach sexual maturity between 20 and 50 years of age

Green sea turtles have a slow growth rate and take several decades to reach maturity. Male green sea turtles become sexually mature between the ages of 20 and 50, while females reach maturity between the ages of 25 and 35. However, some sources state that it takes green sea turtles anywhere from 20 to 50 years to reach sexual maturity. This wide range is due to variations among different populations of the same species.

During the mating season, male green sea turtles actively compete for the attention of females. This competition involves flipping, biting, and jostling among the males, while the female tries to find a suitable partner. Once the female has chosen her mate, the pair engages in a unique courtship dance, swimming together in circles. This dance helps the female assess the male’s fitness and readiness to mate.

Green sea turtles do not mate for life and are known to have multiple partners throughout their lifespan. They exhibit a behaviour called "mate fidelity", where they return to the same mating grounds year after year, seeking out familiar partners. This behaviour is not exclusive, as they mate with different partners during a single breeding season. This behaviour ensures genetic diversity and increases the chances of successful reproduction.

The mating behaviour of green sea turtles is polygynandrous, meaning both males and females mate with multiple partners. This strategy further enhances genetic diversity and improves the chances of successful reproduction.

They are not monogamous and have multiple mates throughout their lives

Green sea turtles are not monogamous and have multiple mates throughout their lives. They are known to engage in multiple mating encounters, sometimes even with different partners during a single breeding season. This behaviour ensures genetic diversity and increases the chances of successful reproduction.

During the mating season, male green sea turtles actively compete for the attention of females. Once a male successfully mates with a female, he may move on to mate with other females as well. This behaviour is known as "mating frenzy", where multiple males try to mate with a single female. This frenzy involves flipping, biting, and jostling among the males. The female, on the other hand, tries to find a suitable partner amidst this chaos.

Female green sea turtles can mate with more than one male in a season. As a result, each nest can have embryos of different fathers. Female sea turtles can also store sperm, so consecutive nests can have embryos of the same father. Storing sperm allows females to fertilize their eggs with sperm from different partners. This behaviour, known as polyandry, is quite unique among sea turtles and adds an interesting twist to their mating habits.

Green sea turtles exhibit an incredible ability to navigate vast distances to return to the exact beach where they were born to mate and lay their eggs. This remarkable homing instinct, known as "natal homing", plays a crucial role in the species' survival.

Male turtles compete for female attention during mating season

Male green sea turtles compete fiercely for female attention during the mating season. This competition is necessary as mating with a female is a challenging and dangerous endeavour. The male must hold onto the female while she supports the weight of both of them, all while making regular trips to the surface to breathe.

During the mating season, male green sea turtles engage in a behaviour known as a "mating frenzy", where multiple males will try to mate with a single female. This frenzy can involve flipping, biting, and jostling among the males. The female, in the midst of this chaos, must select a suitable partner. Once she has made her choice, the pair will swim in circles, performing a unique courtship dance. This dance allows the female to assess the male's fitness and readiness to mate.

The male will then climb onto the female's back and hold on to her carapace with the long, sharp claws of his front flippers. The male's tail, which is very long compared to the female's, reaches under her shell for insemination. The female sea turtle must support the weight of both turtles and regularly swim to the surface for air. This challenging process is even more difficult when several males are competing for her, and in some cases, the female may be at risk of drowning.

After mating, the male will try to remain attached to the female to prevent other males from mating with her. However, other males may compete aggressively, biting the first male's tail and flippers to make him let go. This competitive behaviour ensures that only the strongest males are able to mate, increasing the chances of successful reproduction.

While green sea turtles do not form lifelong monogamous bonds, they do exhibit a certain level of fidelity, often returning to the same mating grounds year after year and seeking out familiar partners.

Females can store sperm from multiple males to fertilise their eggs

Green sea turtles typically take 20 to 50 years to reach sexual maturity, and females only breed every three to four years. When they do breed, female green sea turtles can mate with multiple males.

Female sea turtles are known to have multiple mates, but the reasons for this are not yet fully understood. One theory is that mating with multiple males ensures fertilization, acting as a form of "fertilization insurance". However, this theory has been called into question by researchers from Florida Atlantic University, who found that 75% of female sea turtles in their study had mated with a single male.

Female sea turtles have the ability to store sperm, allowing them to fertilize multiple clutches of eggs with sperm from a single mating. This ability to store sperm may explain why most of the female sea turtles in the Florida Atlantic University study had mated with only one male. The researchers suggested that the females likely mated at the beginning of the season and used the stored sperm to fertilize multiple clutches of eggs.

The ability to store sperm allows female sea turtles to ensure fertilization without the need for repeated mating. This is particularly important for green sea turtles, as there is often asynchrony between mating and nesting seasons. Female green turtles typically lay their first clutch of eggs about five weeks after mating in captivity, but this interval can be as long as two to three months for free-ranging green turtles.

Green sea turtles migrate to their natal beach to mate and nest

Green sea turtles are highly migratory and undertake complex movements and migrations. They migrate between their foraging and nesting habitats, and seasonally to warmer waters. These migrations can take them thousands of miles.

During the breeding season, the males arrive in offshore waters first and wait for the females to come to the beaches. Adult males can breed every year, but females only breed every three to four years. After mating, the female will arrive on the beach and dig a hole in the sand to lay her eggs. She will lay 75 to 200 eggs on average and then cover the hole with sand. She may lay several clutches of eggs before leaving the nesting grounds.

The female green sea turtles migrate to their natal beach, or the beach where they were born, to nest. They will travel long distances, even across oceans, to return to their preferred breeding site. Most females will return faithfully to the same beach each time they are ready to nest, often emerging within a few hundred yards of where they last nested.

It takes green sea turtles at least 20 to 50 years to reach sexual maturity. Once they are sexually mature, they will migrate to beaches around the world to nest.

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