Five cygnets were among eight swans killed in three months

Colin Staplehurst, who runs Staplehurst Butchers, in High Street, Lewes, decided to offer �500 to help catch a gang of youths seen attacking the birds.

His offer was then matched by a customer, putting the reward at �1,000.

Mr Staplehurst said: "I couldn't believe anybody could do anything like that - I was incensed when I saw it."

They seem to be actually trying to reel the swans in Wildlife campaigner Trevor Weeks

Wildlife campaigner Trevor Weeks said the recent series of attacks on swans was the worst he had seen in 18 years.

Mr Weeks, from East Sussex Wildlife Rescue and Ambulance Service, said eight swans had been killed along the south coast in the past three months.

Five of these were cygnets, killed in Lewes only a few days after they had hatched.

Swans have also come under threat at Princes Park, in Eastbourne.

Mr Staplehurst has put up a �500 reward, matched by a customer

Mr Weeks said: "In the last month we've had numerous reports of youths down here with pieces of wood with line attached and a metal hook attached.

"They seem to be actually trying to reel the swans in."

Mr Weeks and other wildlife volunteers are now patrolling parks in East Sussex to try to defend the birds, who are protected.

He said: "They have to be one of the largest birds that we have in this country and obviously the most elegant and most majestic of birds.

"What have they done to these yobs at the end of the day? They don't deserve this."