Owners of aquarium fish are being warned not to keep koi carp without authorisation or risk a hefty fine.
Fisheries Victoria executive director Travis Dowling said koi carp posed a significant risk to native populations in lakes and rivers.
‘‘It is illegal to hatch, grow, hold, buy, sell or transport any noxious aquatic species,’’ Mr Dowling said.
‘‘These are all invasive species that potentially threaten wild ecosystems by out-competing native fish and destroying natural habitat.’’
Mr Dowling said noxious aquatic species included koi carp, common carp, mosquito fish, oriental weather loach, tilapia and cichlids, and permits for these species were only given in exceptional circumstances.
■ To report the presence of noxious aquatic species, including koi carp, call 13FISH (133474) any time.