In a rarely seen event, scientists have recorded a snake catching, killing and eating a vampire bat on a cave floor in Ecuador. In a film released by scientists, a rainbow boa can be seen ingesting a large female vampire bat – one of three bat species that feeds exclusively on blood.
Publishing their report in the journal Subterranean Biology, the team said this is the first time a rainbow boa has been recorded catching a bat on a cave floor, confirming this as a location where snakes can hunt the winged mammals.
A team of scientists led by Sarah Martin-Solano, from the Universidad de las Fuerzas Armadas, ESPE, described the event in detail. It took place in the 450m-long Tena cave in the Amazon rainforest and, in total, lasted 25 minutes.
The bat flew into the cave above the boa's head. The 140cm-long snake rose 30cm off the ground to snatch the bat out of the air. It took the bat to the ground and strangled it for seven minutes, despite the bat stopping struggling after two. The snake then tried several positions to fit the bat in its mouth before eventually swallowing it whole – a process that took four minutes and 50 seconds.
"This study confirms that predation of bats in caves by snakes does occur," the team wrote. "This is the first report for Ecuador, of Epicrates cenchria predating on a Desmodus rotundus, in a cave, and the third report for Latin America. With such a few reports, we cannot affirm that this kind of predation is common, but we suggest that a detailed study in this population would help us confirmed that this behaviour is more than usual."