Have you ever seen 64,000 migratory turtles all at once? Now’s your opportunity to shine.
The world’s largest green turtle rookery has been discovered moving off the coast of Raine Island, a 32-hectare vegetated coral cay off the coast of north-eastern Australia, with an estimated 64,000 endangered green turtles.
The stunning drone footage was shot in 2019 as part of the Raine Island Recovery Project, which attempts to save the lonely coral cay. Green turtle (Chelonia mydas) populations that use the region to spawn have been declining owing to habitat degradation and overfishing, and the IUCN Red List now lists them as endangered.
Scientists on the island are hard at work restoring nesting beaches and erecting fencing to protect the 60,000+ female green turtles that come to lay eggs here every year in one of the world’s “biggest animal migrations.”
“These remarkable drone photographs are helping to chronicle the greatest turtle populations seen since we launched the Raine Island Recovery Project,” said Great Barrier Reef Foundation Managing Director Anna Marsden.
Since 1984, scientists have been painting hundreds of green turtles before visually counting individual animals and estimating their numbers on Raine Island — a tough and time-consuming process.
“In the past, when green turtles were breeding on the beach, previous population census methods entailed painting a white stripe along their shells. The paint is non-toxic and washes off in a few days, according to Queensland Department of Environment and Science spokesperson Dr Andrew Dunstan. “We next counted painted and non-painted turtles from a small boat, but eyes are drawn to a turtle with a brilliant white stripe considerably more than an unpainted turtle, resulting in biased counts and lower accuracy.”
Another excellent video illustrating the counting approach can be found here.
Surface observers “consistently reported larger proportions of marked turtles” than either the drone or the underwater approach, resulting in higher population estimates that might have biased conservation efforts, according to the researchers.
However, this is no longer the case. As science and technology collide on the Great Barrier Reef, the Raine Island Recovery Project has already recorded a 100 percent rise in hatchling rates.
Another incredible video of nesting turtles may be seen here.
Raine Island is also home to the oldest European building in tropical Australia, a stone beacon erected in 1844, which is a significant environmental symbol that is completely off-limits to the public. Let’s hope it continues to be thus.