Global warming affects gender ratio of sea turtles | Partners | Belarus News | Belarusian news | Belarus today | news in Belarus | Minsk news | BELTA
ISTANBUL, 24 May (BelTA — Anadolu) — As the rapidly warming planet
affects all life on earth, rising nest temperatures are increasing the
female sea turtle population, according to a Turkish expert.
Since 2000, every year on May 23, World Turtle Day is celebrated to raise awareness and concern for the turtle ecosystem.
In
an interview with Anadolu, Dogan Sozbilen, a board member of the Sea
Turtle Research, Rescue, and Rehabilitation Center (DEKAMER), evaluated
the effects of climate change and global warming on sea turtles.
Sea
turtles are among the species directly affected by temperature, with
the most significant impact on the determination of the sex of the
hatchlings, Sozbilen said.
“When they lay their eggs in the sand,
the sex of hatchlings is not determined; gender determination is not
genetic but is influenced by environmental factors. At a nest
temperature of 29 degrees Celsius on the beach, half of the hatchlings
are female, and the other half are male. When the temperature exceeds
this, the number of females increases, while below this temperature, the
number of males increases.”
“As temperatures rise and this trend
continues, we face the problem of an increasing female population.
Additionally, when temperatures reach 33-34 degrees Celsius, embryo
deaths begin to occur,” Sozbilen said.
Sozbilen noted that due to rising temperatures, sea turtles will seek cooler habitats and reproduce at cooler times.
Predicting
that climate change would significantly impact sea turtles, Sozbilen
added: «Our studies and various projections have shown that sea turtles
will not be able to cope with climate change in their current
reproductive strategies by the year 2100.”
«Shifting their
breeding times to cooler periods will not suffice as well,” he said,
adding one of their studies published in 2023 found that nesting time
shifts worldwide and could extend up to 180 days in the long term, but
these changes alone will not be enough.
Importance of sea turtles for health of marine, coastal ecosystems
Sozbilen
shared that there are seven species of sea turtles living in warm and
tropical regions worldwide, with the loggerhead sea turtle (Caretta
caretta) and the green sea turtle (Chelonia mydas) nesting on Türkiye’s
Mediterranean coasts.
«Türkiye and Greece have the most
loggerhead turtle nests in the Mediterranean. Nearly 80% of green sea
turtle nesting occurs in Türkiye.”
He highlighted the important
ecological roles sea turtles play for the health of both marine and
coastal ecosystems. «Beaches, which are a crucial part of the coastal
ecosystem, are nutrient-poor areas. By laying eggs on these beaches, sea
turtles provide a food source for the plant and animal species sharing
the habitat.”
Meanwhile, sea turtles help balance jellyfish populations by feeding on them, maintaining ecological equilibrium, he said.
Pollution problem
Pollution is a significant problem for the Mediterranean, Sozbilen said.
«Between
2017 and 2022, we measured pollution levels in the digestive systems of
dead or injured sea turtles that washed ashore, with levels exceeding
80% and even reaching 100% in some areas. In Türkiye, this rate is
around 35%, but the areas where we conducted our studies are relatively
clean. We see increasing rates in the Eastern Mediterranean.”
“Plastics
can block sea turtles’ digestive systems, leading to a slow and painful
death. Large pieces can entangle their flippers, causing them to become
weak and unable to feed.”
