Have you ever witnessed 64,000 turtles during one migration?
Now is your chance.
An estimated 64,000 endangered green turtles have been spotted roaming off the coast of Raine Island, a 32-hectare vegetated coral reef located on the outer edge of the Great Barrier Reef off the coast of northeastern Australia. This is the largest green turtle nesting site in the world.
The breathtaking drone video was captured in 2019 as part of a project called the Raine Island Recovery Project, which is trying to protect the isolated coral reef. Populations of the green turtle (Chelonia mydas), whose reproduction depends on the region, are declining due to habitat destruction and exploitation and are currently classified as threatened on the IUCN Red List.
In one of the “greatest animal migrations” on Earth, over 60,000 female green turtles come to the island each year to lay their eggs, and scientists are working hard to restore nesting beaches and install fences to keep the turtles alive.
“These amazing drone photos help document the largest number of turtles we’ve seen since we started the Raine Island restoration project,” said Great Barrier Reef Foundation CEO Anna Marsden.
“We’re seeing the largest aggregation of green turtles in the world.”
Since 1984, scientists have painted thousands of green turtles—a difficult and time-consuming task—to visually count each turtle and determine an accurate population estimate for Raine Island.
“According to previous population survey procedures, the shells of green turtles were painted with a white stripe when they were breeding on the beach.
The paint is non-toxic and can be easily removed within days, according to a statement provided by Dr. Andrew Dunstan from the Queensland Department of Environment and Science.
“We then counted the painted and unpainted turtles from the small boat, but the eye is much more attracted to the turtle with the bright white stripe than the unpainted turtle, resulting in a biased count and reduced accuracy.”
The drones were used by scientists in December 2019 to investigate whether more technologically sophisticated approaches would be more effective.
Next, the group counted the turtles in the lab by carefully examining each video frame and comparing the results to results from GoPro footage taken underwater. The “most effective survey method,” they conclude, is the use of drones because they are safer, more accurate, and allow for permanent data retention.
This fantastic video explains the counting process one more time.
In addition, surface observers “consistently reported higher proportions of tagged turtles” compared to underwater and drone methods, which may have biased conservation efforts due to higher population estimates.
However, this is no longer the case. As science and technology converge on the Great Barrier Reef, the Raine Island Restoration Project has already reported a 100% increase in hatchlings.
The migration of more than 64,000 endangered green turtles to Raine Island is a remarkable spectacle that offers a glimpse into one of nature’s most amazing phenomena. This annual event, where thousands of turtles return to lay their eggs, underscores the importance of conservation efforts like the Raine Island Restoration Project.
As green turtles face significant threats from habitat destruction and exploitation, the use of advanced technology such as drones has proven to be key to monitoring and protecting their populations. The shift from traditional counting methods to drone-assisted surveys has not only improved accuracy but also ensured safer and more efficient data collection.
The collaboration between science and technology has already produced impressive results, including a 100% increase in hatch success. This progress is a testament to the dedication of researchers and conservationists working to protect these endangered creatures and their sensitive ecosystems. As these efforts continue, we hope that future generations will be able to witness the extraordinary migration of green turtles and appreciate the steps that have been taken to protect their survival.