Children love parks in the summer: lazy days spent in the paddling pool, on the slide or playing football in the sunshine. But parents are becoming increasingly worried about their children's safety in the playground or village green. The menace? Off-the-lead dangerous dogs.

Nothing is guaranteed to clear a park faster than an unrestrained rottweiler or Staffordshire bull terrier. Although their owners may claim that their pets are harmless, to worried parents they are the canine version of the Bogey Man.

While dogs are supposed to be man's best friend, recent casualty figures, coupled with well- publicised horror stories about attacks, suggest that some may be our children's worst enemy. The number of under-18s treated at A&E departments for dog bites rose by 119 per cent in London and 80 per cent in the West Midlands last year, according to the NHS. In London 127 children needed hospital treatment last year compared with 58 in 2003.

The reason is that an increasing number of dogs are out of their owners' control in public places. Police, park rangers and animal charities say that dangerous dogs are being used by gangs as status symbols and becoming a growing public menace.

Many parents are increasingly worried about their children's safety around controversial breeds such as Staffordshire bull terriers and rottweilers. Louise Barnes, a mother of two from Huddersfield, in West Yorkshire, says: “It's getting worse and worse. Sometimes I feel that we're being pushed out of the parks by off-the-lead dogs and their irresponsible owners. I'm terrified that my kids are either going to be attacked or knocked over by dogs whose owners either can't or won't control them.”

Two bull terrier puppies leapt on Nancy Strang's oldest son, Albert, in a North London park when he was only 12 months old. Albert was knocked to the ground and although he was not harmed, the experience left him shaken.Strang says: “There are quite a few men in my area who have dangerous dogs as pets. They seem to think it helps them look hard. When Albert was attacked, what really annoyed me was that the owners were totally unapologetic about it. They just got very defensive.”

The bull terrier jumped on her buggy

Most parents have a horror story or “near miss” to report. My daughter's first close-up encounter with a dog was one sunny day last summer in our local West London park when she was just 1. All the dogs in her picture books are doe-eyed mutts called Spot or Rover who like playing ball and burying bones, so it is understandable that she wailed like a banshee when a Staffordshire bull terrier jumped on to her buggy and started sniffing her face. I froze and didn't know what to do.

Should I swat the dog off? Spin on my heel and run for the hills (with the buggy, of course)? Or cross my fingers and hope for the best? (See below, for advice.) Eventually the owner - rather stereotypically, a twentysomething skinhead - came over and told me not to worry because his dog was a “sweetie” who “wouldn't hurt a fly”.

Scant consolation: after all, in the same summer the death of five-year-old Ellie Lawrenson in St Helens, Merseyside, had put dangerous dogs back in the headlines. Ellie was shaken to death by her uncle's pit bull terrier, who locked its jaws around her throat in a prolonged attack. Pit bull terriers are among the breeds banned by the Dangerous Dogs Act 1991.

So should this growing fear of dog attacks be taken seriously? In London last year almost 1,000 dogs were reported as being dangerously out of control in public. The RSPCA received 750 complaints about dog-fighting and dog attacks in English streets, compared with 192 incidents in 2002. Meanwhile, 3,800 people were treated in hospital for dog bites, an increase of 43 per cent over the previous four years.

Tom Jarvis, the park manager of Kensington Gardens in London, says: “The problem of antisocial dogs is getting worse and affects all park users. It's particularly worrying for parents. Because children are small, they're more vulnerable. Just today I had to deal with two bull terriers being goaded by their owners to fight each other, and since November we've had 13 swans killed by out-of-control dogs.”

Norman Baker, a Liberal Democrat MP, regularly hears similar stories from his Lewes constituents. He believes that dangerous dogs are being used as fashion accessories or, worse still, as weapons. He says: “Dogs often only become violent as a result of mistreatment by owners or because of a failure to train them properly. Irresponsible owners are more likely to make a dog ‘dangerous' than it being born a particular breed.”

“Violence is invariably the owner's fault”

Despite the new research figures, and what feels like increasing anecdotal evidence, the Dogs Trust, a leading animal welfare charity, says there is no cause for alarm and that although dog attacks on humans generate headlines, they are relatively rare. Clarissa Baldwin, the trust's chief executive, says: “The likelihood of a dog attacking a child is minimal. There are more than six million dogs in this country and most are harmless. Any violence is invariably the fault of the owner. We should focus on the deed, not the breed.”

Caroline Kisko of the Kennel Club, agrees it is important not to demonise dogs. She says: “We associate particular types of dogs with aggressive behaviour, but the breed is actually irrelevant. It's all to do with the idiot on the other end of the lead. If you buy a dog because you want to look macho and to train it to be vicious, then you're not going to buy a chihuahua, are you? You'll buy a Staff.”

Under the Dangerous Dogs Act, a dog classed as being “dangerously out of control in a public place” can be destroyed. But instead of further legislation, animal welfare groups say that the emphasis should be on encouraging responsible dog ownership and better training.

Inga MacKellar, an animal behaviourist, says: “Dog attacks occur when a dog hasn't been properly trained. The first three to 12 weeks of a dog's life are crucial and it's important that they meet lots of different people, young and old. They're like human beings really, and are as fearful of the unknown as we human beings are. Most dog owners are responsible, but as ever, it's the minority who are ruining it for the majority.”

HOW TO PLAY IT SAFE WITH DOGS

Never allow a child to touch an unknown dog without the owner's permission.

Never leave your child unsupervised with a dog, even the family pet. Most dog attacks happen at home to the under-7s.

Dogs don't like being patted on the head or having their tails pulled, so teach your child to stroke dogs gently and from the side.

Dogs can find being cuddled intimidating.

Never disturb a dog who is eating or sleeping.

If a dog hides under a table or bush, do not allow your child to follow. The dog is probably feeling threatened and seeking a refuge.

If a dog threatens you: cross your arms over your chest, look down and stand still. If the dog persists, slowly curl up on the floor, protect your head and stay still. Never run. Avoid eye contact, which dogs may see as confrontational.

Dogs are fascinated by babies in buggies. Most dogs are friendly and probably just want to say hello. If you feel threatened, lean over the buggy to protect your child.

If the dog is interested in your child's toy or lunch, throw it on the ground for him.

In the unlikely event that your child is attacked, try to distract the dog (ideally by throwing water at it).

If there is a potentially dangerous dog in your area, inform the police. It is their responsibility to intervene.

If you are in a park, find a warden. Under the Clean Neighbourhoods and Environment Act 2005 local authorities were given the power to introduce control orders for dogs and dog owners.

The Blue Dog CD, published by Company of Animals (www.companyofanimals.co.uk), is an excellent interactive dog safety guide. The Kennel Club (www.thekennel club.org.uk) has more good advice.

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