The Environment Agency is patrolling the River Severn to watch out for elver poachers.
They're using boats with special imaging equipment so they can see in the dark. Other officers patrol the banks.
The baby eels are a delicacy in the Far East and can command a high price, but fishing is strictly controlled. Anyone doing it without a permit can be prosecuted.
Bill Burleigh is an Environment Agency Fisheries Officer:
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More rain and wind will move in on Friday before the cold weather takes over for the weekend.
It will be cloudy and mild with some brightness today but rain will move in overnight, becoming heavier tomorrow afternoon.
Tennis star Pat Cash, TV presenter Kevin McCloud and Bristol Mayor George Ferguson have helped plant a community orchard in Bristol.