In 2020, Yuha Hasegawa, a graduate student at Nagasaki University, watched as an elver, or a young eel, was put into the same tank as a carnivorous freshwater fish known as a dark sleeper.
The dorsal fin runs the length of its body and the upper jaw extends beyond the lower one. After an amazing migration to the centre of the Atlantic the mature conger eel spawns only once and then ...