The Japanese eel ( Anguilla japonica ) is an important fisheries species in East Asia, with stocking programs implemented to enhance local fisheries. However, the downstream movement of stocked eels, which has been reported in previous studies, may reduce the stock enhancement effect due to emigration from fishery sites. To investigate the immediate movement of stocked eels, passive integrated transponder (PIT)-tagged eels wer...

Understanding the feeding habits of predatory fish is essential for unravelling food web structures and implementing conservation strategies in riverine ecosystems. However, conventional lethal stomach content analysis methods are not necessarily appropriate for long‐term dietary studies, particularly for threatened species, as they require large sample sizes due to the inability to repeatedly analyse stomach contents from the...

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 do...

Eight silver‐phase male Indo‐Pacific eels (giant mottled eels) Anguilla marmorata were collected from three small rivers on subtropical Amami‐Oshima Island, Japan, and their morphological and gonadal‐histological characteristics were examined. The total length, body mass and age of the silver eels were 543.8 ± 49.3 (496–659) mm, 376.0 ± 116.0 (282–660) g and 14.6 ± 2.3 (11–19) years old, respectively. The silvering‐related cha...

Modes of reproduction in animals are diverse, with different modes having evolved independently in multiple lineages across a variety of taxa. However, an understanding of the genomic change driving the transition between different modes of reproduction is limited. Several ricefishes (Adrianichthyidae) on the island of Sulawesi have a unique mode of reproduction called “pelvic‐fin brooding,” wherein females carry externally fe...