A report by Christie Wilcox for Gizmodo.
As twilight descends, nocturnal bat species rouse from their daily resting places to feed, creating spectacular clouds as they pour out of caves en masse. But look closer at Jamaican fruit bat colonies as they emerge from sinkhole caves in Cuba, and you may catch a glimpse of a concurrent macabre ritual: As the bats erupt from the cave, a deadly curtain of Cuban boas hangs in their path, aiming to snatch the winged creatures mid-flight.
That’s right—these snakes coordinate their attacks, and the result is terrifying.
Vladimir Dinets, a research assistant professor at the University of Tennessee, Knoxville, was guiding a bird- and mammal-watching tour through Desembarco del Granma National Park, Cuba, when he first noticed the cavern-hunting snakes. Intrigued by the bold behavior, he decided to take a closer look.
The boas involved could all be found basking near the cave’s entrance during the day, while the bats slumbered in an adjacent chamber separated by a narrow passage. As daylight faded, some of the snakes would move from their warm nooks into the passageway.
There, they would dangle their serpentine bodies from the ceiling, ready to strike as bats flew past. Other snakes would take up similar hunting positions as dawn approached, catching the bats as they returned. During each potential feeding opportunity, Dinets dutifully recorded the position of the snakes as well as their hunting success, or lack thereof.
While the snakes coordinated with one another, it’s not quite accurate to say they hunted in a “pack” like wolves, as that implies a social aspect that Dinets didn’t see. “I saw no evidence of direct communication,” he told Gizmodo. “They just take each other’s positions into account.”
Intriguingly, this isn’t the first cave where serpents have been observed hunting bats mid-flight. Writer, ecologist, and wildlife photographer Neil Losin and his colleagues have observed a similar strategy among snakes in Puerto Rico. “We saw up to 8 boas hunting at the same time, and it’s certainly quite a ‘gauntlet’ for the bats to run,” he said. But he and his team only observed and filmed—they didn’t perform quantitative science to determine if the boas were coordinating their hunting.
There’s also the famous Cavern of Serpents near the village of Kantenmo, Mexico, where tourists flock to see snakes snatch bats as they exit for the evening. Again, no one has looked closely for coordination. But given the number of examples of this style of cavern feeding, “it is possible that coordinated hunting is not uncommon among snakes,” Dinets said. “But it will take a lot of very patient field research to find out.”