Production of leptocephali of Japanese eel (Anguilla japonica) in captivity

Despite intensive research on wild and captive eels, no resource has so far provided access to all life cycle stages of the Japanese eel Anguilla japonica. The transition from the preleptocephalus (newly hatched larva) to the leptocephalus stage (typical leaf-like eel larva) has, therefore, remained the missing link in the eel life cycle. We recently found that a slurry-type diet made from shark egg powder is suitable feed for captive-bred eel larvae. The larvae were successfully reared with this diet in aquaria for 100 days and raised to 22.8 mm in total length (TL). Age, TL. and body proportions of the reared specimens overlapped with those of wild leptocephali. We revealed for the first time the transition from the preleptocephalus to the leptocephalus stage of the eel. (C) 2001 Elsevier Science B.V. All rights reserved.