Sea level rise has been a consistent issue in the last couple of decades, and with the early onset of Antarctic ice sheet instability, it is predicted that the global sea level rise‘will reach 82 centimetres and—in extreme scenarios—could exceed two metres’.
Turtle nesting beaches with low slopes may be at risk in the expected increase in sea level rise. | Joe Cook / Unsplash
The rise of sea levels is threatening many oceanic species. Sea turtles are a reptile species that have been around for nearly 110 million years and are now in severe danger, with three out of seven sea turtle species being critically
endangered.
There are seven identified species of sea turtles; the Green Head, LoggerHead, Hawksbill, Leatherback, Kemp’s Ridley, Olive Ridley and Flatback sea turtles. The most vulnerable habitats to sea level rise are those off of small tropical
islands, which are the habitats that the majority of sea turtles live in. Many of the species are facing nesting complications due to increasing sea levels.
‘Three out of seven sea turtle species being critically endangered.’
A 2023 study has investigated the effect of sea level rise on five nesting sea turtle species, all classed as vulnerable or critically endangered. The study used modelling to assess how the future of the species would be impacted.
Overall, leatherbacks were identified as the sea turtle species at higher risk from flooding compared to other species studied, due to their tendency to nest in open areas near high tide. Moreover, the model’s ability to predict these areas
as potential nesting sites was 79.4% accurate.
Leatherback turtles are at high risk of losing nesting beaches according to a recent study. | Cataloging
Nature / Flickr
These figures are concerning, especially considering stabilising global greenhouse emissions to counteract rising sea levels is a challenging prospect that entails significant global cooperation. Researchers also emphasised the importance
of monitoring these habitats to understand the projection of the rookeries and how we can help sea turtles nest safely.
The countries surveyed were Costa Rica, Cuba, the United States- specifically Florida, Ecuador and Australia. However, the research stated that the nesting habitats of sea turtles are usually in poorer countries that cannot afford the
technology to monitor the state of the terrestrial land.
‘On average, 50% leatherback, 18.2% hawksbill and 13.1% of green turtle nest locations would be flooded by 2050’
Another recent study showed the effect of climate change on Mediterranean marine life and looked closely at threatened species including sea turtles.
The study aims to elucidate how these species will adapt to, or be impacted by, the changing climate. Results suggest that the flooding of sea turtle nesting beaches will likely cause this species to struggle to reproduce. Looking to the
future, there may be fewer sea turtle rookeries and there could be a 100% loss of nesting beaches in places such as Australia and Florida.
The nesting process of sea turtles goes back millions of years, unfortunately, this process is being threatened by anthropogenic climate change having a serious effect on sea turtle reproduction.
During the reproduction process, sea turtles will return to land to find a suitable nesting location for their young. Each time a female sea turtle nests she tends to go back to a nesting location she has previously used or is at least
familiar with. When nesting, the female will create a ‘body pit’, with her flippers in the sand, this will create a perfect arrangement for her to nest.
Monitoring the situation and the beaches where the sea turtles nest is a successful way that we can help identify nesting locations for female sea turtles. For example, a recent study trialled researchers using drones to take images to
photograph structures of different sea turtles nesting on beaches in north Cyprus.
Researchers from the Centre for Ecology and Conservation at the University of Exeter, UK, describe 'automated drone surveillance which can record sequences of photos on the surface below, then merged to construct three-dimensional models of
the survey area in a process called photogrammetry.'
Therefore, these drones can quickly help to identify which beaches need to be prioritised for local conservation. Charities such as the World Wide Fund for Nature (WWF) are working with local communities in Indonesia, Ecuador and Fiji to
prevent the beaches from completely flooding.
‘Results suggest sea turtle nesting beaches flooding will likely cause this species to struggle to reproduce.’
Although local communities can try their best to conserve the beaches, it is also important that global greenhouse emissions are decreased to mitigate global sea level rise. This is essential for sea turtles to be able to successfully nest
and for other marine life to survive in their natural habitats.
Chatzimentor A., Doxa A., Katsanevakis S., Mazaris A.D. (2022) Are Mediterranean marine threatened species at high risk by climate change?, Global Change Biology.Volume 29, Issue 7, Pages 1809-1821.
Florida Fish and Wildlife Conservation Commision (n.d.) 'The History and Life of a Sea Turtle.' Research. Available at:
https://myfwc.com/research/wildlife/sea-turtles/florida/life-history/#:~:text=Sea%2520turtles%2520are%2520among%2520the,they%2520face%2520an%2520uncertain%2520future [Accessed July 1st, 2023].
Klinges D. (2018) 'Drone 3D Models help assess risk of turtle nesting beaches to sea level rise.' Mongaby. Available at:
https://news.mongabay.com/2018/12/drone-3d-models-help-assess-risk-of-turtle-nesting-beaches-to-sea-level-rise/ [Accessed July 7th, 2023].
Lyons M., et al. (2020) Quantifying the Impacts of Future Sea Level Rise on Nesting Sea Turtles in the Southeastern United States, Ecological Impacts. Volume 30, Issue 5.
Martins S., et al. (2022). Potential Impacts of Sea Level Rise and Beach Flooding on Reproduction of Sea Turtles, Climate Change Ecology.Volume 3.
Mercado A. (2023) 'Sea Level Rise Will Wash Away Sea Turtle Breeding Grounds.' Gizmodo, Available
at:https://gizmodo.com/sea-level-rise-turtle-breeding-grounds-climate-change-1850363591#:~:text=Climate%20change%20is%20coming%20for,sea%20turtles%20lay%20their%20eggs [Accessed July 4th, 2023].
Milman O. (2015) 'Turtles' future at risk as scientists show rising sea levels affect egg hatchings.' The Guardian. Available
at:https://www.theguardian.com/environment/2015/jul/22/turtles-future-at-risk-as-scientists-show-rising-sea-levels-affect-egg-hatchings#:~:text=7%2520years%2520old-,Turtles'%2520future%2520at%2520risk%2520as%2520scientists%2520show,sea%2520levels%2520affect%2520egg%2520hatchings&text=Rising%2520sea%2520levels%2520could%2520decimate,from%2520being%2520swamped%2520by%2520seawater
[Accessed June 20th, 2023].
Rivas M., Rodríguez-Caballero E., Esteban N., et al. (2023) Uncertain Future for Global Sea Turtle Populations in Face of Sea Level Rise, Scientific Reports.Volume 30, Article number 5277.
Sea Turtle Conservancy (n.d) ‘Information About Sea Turtles: General Information.’ World Wildlife Available at: https://www.worldwildlife.org/species/sea-turtle.[Accessed June 20th, 2023].
Varela M.R., Patrício A.R., Anderson K., et al. (2019) Assessing climate change associated sea-level rise impacts on sea turtle nesting beaches using drones, photogrammetry and a novel GPS system, Global Change Biology.
Volume 25, Issue 2, Pages 753-762.
World Wildlife Fund (WWF) (n.d.) 'Sea Turtles.' WWF. Available at: https://www.worldwildlife.org/species/sea-turtle [Accessed June 20th, 2023].
