Abstract
Anguilla marmorata collected in the Odana River lower reaches were passive integrated transponder‐tagged displaced and released into the upper river reaches (54 up‐transported eels), and eels collected in the upper reaches were tagged and released downstream (52 down‐transported eels). Their movements were detected once per day for 10 days using a portable radio‐frequency identification (RFID) system. The homing rate of the down‐transported eels was 38.9%, compared to 3.7% for the up‐transported eels, suggesting that eels inhabiting upstream areas have relatively high fidelity to their habitats and downstream eels have less fidelity.