Dark sleeper fish (Odontobutis obscura) can gulp down young Japanese eels (Anguilla japonica) whole, but the swallowed eels can wriggle back up through the digestive tract and out of the stomach, swimming to freedom through the bigger fish’s gills, scientists recently discovered.
“Witnessing the eels’ desperate escape from the predator’s stomach to the gills was truly astonishing for us.”A Japanese eel exhibits circling behavior along a predator's stomach wall in this X-ray video footage.
But while they observed swallowed eels wriggling tailfirst from dark sleepers’ gills, “we had no understanding of their escape routes and behavioral patterns during the escape because it occurred inside the predator’s body,” Hasegawa said via email.
Once a predator swallowed an eel, the sated fish was quickly moved to a special tank where the X-ray video camera was ready to roll.
On average, it took about 3 ½ minutes for a swallowed eel to reappear and swim away.
Persons:
”, Yuha Hasegawa, Yuuki Kawabata, ichthyologist Kory Evans, “, ” Evans, ’ Hasegawa, Kazuki Yokouchi, Nagasaki University —, ” Hasegawa, Prosanta, Mindy Weisberger
Organizations:
CNN, Graduate School of Fisheries, Environmental Sciences, Japan’s Nagasaki University, “, biosciences, Rice University, Japan Fisheries Research, Education Agency, Nagasaki University, Louisiana State University, LSU Museum of Natural Science, Scientific
Locations:
Anguilla, Houston