Astonishing footage shows a leech leaping across a forest floor in Madagascar, providing “the first conclusive evidence” that at least one species of leech can jump.

By Daniel Graham

Published: Friday, 21 June 2024 at 14:02 PM


Scientists in Madagascar have captured footage of a terrestrial leech jumping.

For a long time, accounts of jumping leeches have been questioned by biologists, suggesting it was more likely that the critters were falling off prey or vegetation rather than springing into the air.

Now, two videos taken by researchers from the American Museum of Natural History, Fordham University and City University of New York (CUNY)’s Medgar Evers College provide “convincing” evidence that leaping leeches are more fact than fiction.

The footage and analysis of this extraordinary behaviour have been published in the journal Biotropica.

“We believe this is the first convincing evidence that leeches can jump and do so with visible energy expenditure,” says lead author Mai Fahmy, a scientist and a postdoctoral researcher at Fordham University.

Fahmy caught the moment on camera in 2017 during an expedition to Madagascar’s Ranomafana National Park. Returning in 2023, this time to the Ivohiboro Protected Area, Fahmy once again filmed the leech – of the genus Chtonobdella  springing across the ground.

“Essentially, it executes a graceful jump but with a seemingly hard landing,” says co-author Michael Tessler, an assistant professor at City University of New York (CUNY)’s Medgar Evans College.

The scientists identified the leech species as Chtonobdella fallax, a common species in Madagascar.

“We do not know how often this may happen or whether these leeches use this ability to seek out hosts, but, given that we caught multiple jumps in two short recordings, this behaviour may be common for this species,” says Tessler.