The mating of Bombay night frogs
Well, here’s a scientific discovery that frog fans will find ribbiting.
If you thought there were only six positions that frogs and toads use to mate, you jumped to the wrong conclusion.
Researchers spent eight hours a night for 40 nights in the monsoon-soaked forests of Western Ghats in India to spy on the nocturnal nookie of the Bombay night frog.
Operation: Jungle After Dark?
These note-taking peeping Toms found the frogs using a mating position they’d never seen before: what they call the dorsal straddle.
Or, as Britain’s The Guardian breathlessly reports: “A mating position never seen before in the wild world of frog sex.”
Or, as scientists not-so-breathlessly describe it: “A new amplexus mode in frogs.”
This newly observed mating ritual is unlike anything previously documented among the world’s 6,650 frog species. Researchers aren’t sure whether this different technique results in anything beneficial for the frogs — such as higher fertilization rates — other than it’s just, well, different.
“It’s remarkable,” Biju told The Guardian. “So far, this mating position is known only in Bombay night frogs.”
Biju first witnessed the frog’s unusual mating technique in 2002, but it took him more than eight years to put a study together, The Guardian reported.
It’s not as if the Bombay night frog is a willing study subject. They are very secretive, breeding only at night and, unfortunately for researchers tracking them down, always at the height of the monsoon season.
Biju and his team found them in the vegetation overhanging flooded forest streams by following the sound of their mating calls. The frogs tend to pair up high in trees, on leaves, branches and tree trunks.
The fieldwork was a “very challenging experience,” Biju told LiveScience. They stood in fast-flowing streams with infrared cameras, trying to keep the equipment dry while they filmed the frogs mating.
Sometimes the frogs fell into the water during sex. They usually returned to the original spot to finish but that could take hours, said Biju, who also noted the “various venomous snakes” hanging around.
Biju and his crew found that mating process begins when the female backs up toward the male, touching his head with her toes.
Once they touch, the male climbs onto her back. But unlike in other frog species whose males holds on to the females — around the waist or armpits or head — the Bombay Romeo instead holds on to nearby branches or leaves to steady himself as he appears to release his semen down the female’s back.
Mating takes an average 13 minutes. Then the female arches her back several times, bumping her mate to let him know she’s good to go. She lays her eggs, then leaves.
“Species such as the Bombay night frog, which are endemic to small regions (most often outside protected areas and threatened with anthropogenic activities), definitely require conservation prioritization,” Biju told LiveScience.
“Therefore, natural history studies not only provide necessary information for planning effective conservation strategies, but also highlight unique frogs, such as the ancient night frogs that exhibit highly diverse reproductive behaviors.”