A clampdown is planned on salmon poachers in a bid to protect the fish as their numbers increase in the region's rivers

Specialist teams from the Environment Agency are to carry out extra checks along the Ouse, Ure, Esk and Tees over the next two months.

Surveillance cameras have also been set up at key locations along the waterways in an effort to spot the poachers at work.

"It is important to stop the illegal capture of these wonderful fish, so they can go on to produce the next generation," said fisheries team leader John Shannon yesterday.

"Numbers are finally increasing in the Ouse system, but only very slowly, and if we want this rosy picture to continue then these fish must be allowed to reach their spawning grounds."

He said: "We're keeping a close eye on the waters and taking a strong line against anyone caught poaching salmon and sea trout. We ask legitimate anglers to return any fish caught to the water unharmed to continue their journey."

The trout fishing season ends this weekend while the salmon and sea trout fishing season continues until the end of October. Moves are also under way to renew the River Esk Tideway Bylaw, which restricts fishing and is due to expire in February.

It was introduced in 1987 to reduce the adverse effects of both legal and illegal fishing on the tidal stretch and was renewed for five years in 1987.

The Agency says the by-law has produced significant results during the past 14 years and needs to be retained as there has been a rise in the number of sea trout and a levelling out in the decline of salmon stocks.

Fisheries, ecology and recreation manager Frank de Planta said: "The Agency's proposed approach safeguards the long-term needs of sea trout and salmon along the length of the Esk.

"The Esk is a superb river and it is our job to ensure that fish are allowed to return to spawn along their traditional gravel beds upstream of Ruswarp weir."