https://canalrivertrust.org.uk/things-to-do/fishing/caring-for-our-fish/freshwater-fish-species/invasive-and-non-native-fish/topmouth-gudgeon
Topmouth gudgeon | Invasive and non-native fish species
Topmouth gudgeon are small freshwater fish native to Asia and are highly territorial. Recognised as harmful to the environment, the Environment Agency have an...
topmouth gudgeonnative fishinvasivenonspecies