2020 Volume 67 Issue 2 Pages 259-264
Reproductive interference and inhibition of reproductive behaviour between two sympatric bitterlings (Itasenpara bitterling, Acheilognathus longipinnis, and rosy bitterling, Rhodeus ocellatus ocellatus) were observed in the Moo River, Himi City, Toyama Prefecture, Japan. Male rosy bitterling and female Itasenpara bitterling individuals formed pairs, subsequently exhibiting interspecific reproductive behaviour. However, female Itasenpara bitterlings failed to lay eggs. Furthermore, rosy bitterlings attacked male Itasenpara bitterlings that defended territories around freshwater mussels, resulting in the latter abandoning their territories. This is the first report of rosy bitterlings negatively impacting the reproductive behaviour of Itasenpara bitterlings.
