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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A sunny but chilly start. Cloud increasing with a little rain affecting northern and western areas, especially over the Derbyshire hills.
After a mainly dry, and locally chilly start, cloud will thicken, with some patchy rain possible across northern counties.
Becoming generally dry overnight with clear spells. A sunny but chilly start tomorrow. Cloud increasing with a little rain for some.