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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He will be replaced by Academy Director and former Rams defender Darren Wassall until the end of the season.
The boy, 7 and girl, 4, were pulled from the rubble by the fire service and airlifted to Birmingham Children's hospital.
Showers becoming confined to the west overnight, some sunshine Tuesday.