Birds are in danger of being wiped out on a lake at Edmonton's Pymmes Park following a suspected outbreak of botulism.

Some 50 ducks and geese have been pulled from the water echoing scenes from 2003, when more than 70 birds died on the poisoned lake.

Over the past three weeks a number of Canada geese, mallards and tufty ducks have been found dead, horrifying a group of residents who are fighting to save the dwindling numbers.

Environmental campaigner Theresa Lefley said: "I fear the remaining birds will be dead by the end of the week.

"We need fresh water to come into the lake, because at the moment the birds are swimming on stagnant, poisonous water. This is an epidemic."

Tests carried out on the water in 2003 revealed the lake had become polluted with sewage and was 4,000 times over the EU bathing directive with extreme levels of coliforms and E-coli bacteria.

The source of the pollution was blamed on Thames Water, which carried out corrective work on misconnected household drains discharging sewage into the lake.

This week a Thames Water spokesman said work was still being carried out on the south side of the lake but pollution was no longer being pumped into the water.

Ms Lefley and fellow campaigners Linda Badham are accusing the council of failing to come to the rescue. She claims the abolition of the park ranger service has left no one on site to offer help and assistance at weekends.

Instead the women say they are relying on overstretched local animal rescue services.

They are calling on council bosses to install a bore hole which can pump clean water into the lake when needed.

Ms Lefley said: "The council hasn't learned its lesson. The signs of botulism are all there. The duck's legs become paralysed, then their wings go and they start sinking.

"It is very upsetting. I saw a dead duck and its five ducklings swimming around it. We have got to the point where we don't want to go into the park, but if we don't look, nothing will get done."

Ms Badham added: "It is an absolute disgrace, and we are not going to let this go, because we really believed the problem must be sorted this time.

"If the council refuses to pump fresh water into the lake then my view is move the ducks now and fill the lake in."

A council spokeswoman said: "Due to the heat at this time of year all large areas of still water are susceptible to naturally occurring botulism which can cause paralysis in wildfowl.

"To reduce the immediate problem we are pumping fresh water into the lake, and we have a rescue team on the lake monitoring the situation every hour.

"To solve the long-term problem the council has applied for a licence to supply water from fountains on a permanent basis via an artesian well. We are currently awaiting consent from the Environment Agency."