A wildlife rescuer says birds and other animals being caught and killed because of discarded fishing hooks is becoming far too common.

Carly Ahlen, who runs Gabo Wildlife Foundation, is pleading with anglers at Brooklands Lake in Dartford to dispose of their equipment properly after she discovered a dead gull trapped in a fishing line.

Carly releasing a rescued Swan back into Brooklands Lake

She said: "I go all the time to monitor the lake and feed the swan I previously rescued but I was appalled to discover a bird trapped in a fishing hook that some careless angler has discarded into the lake.

"I carefully pulled the bird free and cleaned up the long cable that was attached to the fishing hook to prevent further wildlife casualties.

"This death was preventable. It was pure laziness that an angler has left his hook and line. Next it will be a swan that suffers the same fate."

Carly, who has worked as a rescuer for around 26 years, explained that birds often mistake fishing tackle for food which then gets trapped in their mouths.

"It is cruel. It is animal cruelty," she added. "It is so much worse with the fish hooks. It is just too much and too common.

"Thousands of birds are injured or killed each year when they become tangled in man-made materials, like fishing lines.

"I am pleading with anglers at Brooklands to please dispose of used line, hooks, lures and lead weights properly.

"You will be saving the lives of birds and wildlife and looking after the environment. They belong on this planet as much as we humans."

A spokesman for Dartford and District Angling and Preservation Society (DDAPS), which runs the lake, said the club was doing everything it could do to combat the problem.

"It is just trying to get all the people who use the lake to treat it with respect," they said.

"We are on Carly's side. We do everything we can do and welcome any ideas which we will take on board."

The spokesman said all visitors were made aware and encouraged to take their rubbish with them, with the rules printed on the back of their day tickets. They are also reminded at the entrance.

The DDAPS also has a rescuer it calls out to help wildlife that could be injured.

"We do advise visitors to take their rubbish home with them," they added. "Some do and some do not. We do our best and try to help the birds.

"There are a lot of bins around the lake which some people use but some do not but what can you do? It is a tricky situation."

The club's maintenance of the lake includes picking up rubbish, the spokesman said, and there is a tackle shop nearby that offers a recycling service for fishing equipment.

In the same week as discovering the gull, Carly, of St Clements, Dartford, rescued a tawny owl from a different location which had also been caught on a fishing hook.

She said it had been "on the brink of death" but she managed to rescue it in time.

Her foundation, Gabo Wildlife, is devoted to the rescue and rehabilitation of British wildlife and has held successful campaigns against sports such as fox hunting.

Carly added: "It is their habitat we are inpeaching on. Every day I am called out to wildlife emergencies. It is always because of humans whether that is cars, traffic, bonfires or something else.

"It is becoming a lot more common. It is different now – it has got worse for wildlife. There are so many problems."