According to the Department for the Environment, Food and Rural Affairs (DEFRA), non-native invasive species can prey on, compete with and displace native wildlife. The can spread disease and block waterways. They can completely alter the balance of ecology in a water system.
Fish populations can alter, and they can block up waterways which mean boat users have to take different routes. The financial costs can run into millions of pounds.
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Leicester City striker Jamie Vardy has earned himself a place in football's history today after scoring against Manchester United.
Further showers or longer spells of rain for many tonight, heavy at times, particularly over the hills.
Further blustery showers are likely through the night, with these heaviest and most numerous towards the west.