LAKES, canals and rivers across Bexley are being stripped of their swans, other wildfowl and fish by thieves.

Experts say the poachers are using inhumane methods to trap the birds, and have resorted to breaking swans' necks and snapping their legs to incapacitate them.

The thefts have reached such a level the drop in the numbers of wildfowl and large fish has become apparent to wildlife experts.

They believe the birds and fish are being stolen to eat.

One incident, when swans were captured in nets from Southmere Lake, Thamesmead, was seen by eyewitnesses who alerted police.

Over the weekend, members of Thamesmead Angling Association retrieved a net hidden in the bushes by the canals in Thamesmead town centre, which is believed to have been used for illegal fishing.

Steve Pyke, green spaces manager for Gallions Housing Association, which owns the Thamesmead lakes, thinks the net, made of mesh, has been used to scoop large numbers of fish from nearby Birchmere lake. This is a competition fishing lake where fish can reach up to 40lb in weight.

Now police are appealing for people to come forward if they spot anyone in the act of poaching wildfowl or fish, or have any information about the thieves.

Bexley police wildlife officer PC John Horton has taken charge of the investigation and said the eyewitness reports were "disturbing".

He says people have been spotted at Southmere Lake at around 5am luring the swans with food, then throwing nets over them before killing them, stuffing their bodies into black bin bags and taking them away.

PC Horton said: "The descriptions we have so far is three or four men were involved. But we have no idea who is responsible."

He believes they were being taken for eating.

PC Horton added: "There is no other reason for taking them. There is no resale market.

"There are rumours eastern Europeans are responsible, but we have no evidence of this."

In the case of swans, the cygnets stay with their parents for up to 12 months, so killing a swan could endanger all of its young.

PC Horton said: "The thieves break swans' legs as their legs are very strong and their feet have claws which can cause deep cuts."

Riverkeeper Ashe Hurst has noticed a drop in numbers at locations across the borough, including Thamesmead's lakes and canals.

He also has concerns about the River Cray and the lakes at Foots Cray Meadows and Danson Park in Welling.

He says the thieves are grabbing as many creatures as they can.

Mr Hurst added: "Their methods are crude, inhumane and illegal.

"Sometimes environmental reasons can be responsible for a drop in numbers, but if we are losing a whole brood of birds, there is nothing to replenish the stock."

He claims among the methods used by the thieves are static lines to catch fish, which he says are illegal but often used abroad, as well as airguns and bows and arrows.

Mr Hurst agrees the most likely reason they are being taken is for food, but added: "Some are just attacking wildlife for the sake of it."

A spokesman for Gallions Housing Association said: "We will not hesitate to take action against anyone seen harming or stealing the swans, geese, fish or other animals and we have increased our neighbourhood patrols."

Anyone caught stealing wildlife or fish can face up to six months in prison.

People who see someone attempting to steal wildlife are being warned not approach them.

They should call PC Horton on 07968 598116, the Met Police wildlife unit on 020 7230 8898, Crimestoppers on 0800 555111 or the Environment Agency's 24-hour hotline on 0800 807060.