Rare Hybrid Turtle Hatchlings Found at Queensland Beach

Scientists got an adorable surprise while monitoring nests at Mon Repos beach near Bundaberg, Australia: 15 baby turtles that are part green turtle, part loggerhead turtle.

Conservation officer Dr. Kimberly Finlayson was counting scales on hatchlings with volunteers when something looked off. What she thought was a loggerhead baby actually had the features of a green turtle.

She'd discovered something researchers hadn't seen at this beach in nearly a decade.

Mon Repos is the largest loggerhead turtle nesting site in the South Pacific, about 400 kilometers north of Brisbane. Between January and March, Dr. Finlayson monitored a returning mother loggerhead and found the hybrid babies in two of her clutches.

Two hybrids appeared in one nest. That prompted the team to check another clutch more carefully, where they found 13 more out of 42 hatchlings were hybrids.

The tiny turtles exist because male turtles from different species sometimes mate with the same female when breeding grounds overlap. What makes this discovery special is that green turtles and loggerhead turtles separated as distinct species over 50 million years ago.

"The fact they can still hybridize is pretty unique," Dr. Finlayson said.

Why This Inspires

Most hybrid animals can't reproduce, but scientists don't yet know if these turtle babies will be able to have their own offspring one day. Two of the hatchlings were sent to Sea World to help answer that question.

Aquarium supervisor Siobhan Houlihan said the last hybrids they studied were at Sea World 35 years ago. One female lived until 2020, giving researchers decades of data.

The new babies looked like green turtles at first, making them easier to spot among their loggerhead siblings. As they've grown, they're starting to look more like loggerheads.

Sea World and the Department of Environment will study the hybrids for a couple of years to learn how they grow and develop. The remaining 13 babies were released into the ocean, while the two at Sea World will eventually join them after the research is complete.

Dr. Finlayson suspects hybrid turtles might be more common than scientists realize, since researchers can't examine every single hatchling that makes the journey down the beach to the water.

These little hybrids are giving scientists a rare window into how ancient species can still create the next generation together.