60 pounds of pure intimidation

Jacqueline Rosen was driven to the local animal shelter by her maternal instincts. The single New Yorker was feeling the need to take care of something, and thought a dog would be just the right mix of friend and dependent. She never thought the dog would end up taking care of her.

But the puppy she bonded with in the shelter nursery soon grew up from the eager ball of fur that she named Harry because she thought he had a man's grizzled face. With her German Shepherd-Chow now tipping the scale past 60 pounds, Ms. Rosen has a protector that she calls "Shmoo," but some others call scary.

"I had no idea he was going to be this big," Rosen says. When Harry no longer fit into the large cage where he stayed at night, it made Rosen nervous about what she was raising. But when one look at Harry started sending passers-by to the other side of the street, Rosen came to like the idea of owning a big dog.

"It does feel wonderful to go out alone at 2 a.m. and walk my dog and not feel afraid," she says. A construction worker working on Rosen's building recently appeared on his platform outside an open window of her apartment. She heard Harry growl and saw the man dive for the platform's down button.

"I saw this look of ultimate fear on his face, and that made me feel great," she says.

It's not that Rosen or most other women who own protective dogs get a thrill from scaring off innocent people. Unlike some inner-city youth who keep pit bulls on bicycle chains to boost their street status, women who own protective dogs - beyond appreciating the companionship - are comforted by a sense of security they often do not have when alone on the street.

Harry circles Rosen and a companion as they descend into Riverside Park in Manhattan. The park rates the same as nearby Central Park for safety: a no-no at night and generally fine during daylight hours, but not without incident even then. "He's making sure we're here, making sure we're OK," she explains of Harry's behavior. Loose in the playground, Harry periodically gives up chasing after a tennis ball to come back to Rosen for a reassuring pat. "He always checks in," she says.

Harry, like most pets, is friendly. But Rosen has little doubt that he would turn nasty if anyone threatened her. Her sturdy companion has palm-size paws, sculpted legs, and an auburn and black coat. His pointed ears and very light eyes, along with his size, signal strangers that Harry might be dangerous.

Harry's owner saw his instincts in action when a friend, teasing her, chased after her in the park. "Harry stopped him in his tracks," Rosen says.

Back at home, Harry knows the sound of all of the neighbors' footsteps, and if anyone else visits the building, he growls at the door. "But if someone rings my buzzer for me, he gets very excited and goes to see who's there," Rosen says.

Rosen, who is a baker, grew up in New York, not far from where she lives now.

"When I was a teenager, I had no fear whatsoever. I was never nervous, never afraid," she says. Then came four years of college in quaint Bristol, R.I., "the kind of town where you can leave your door unlocked and don't have to worry about anything."

After that, even as the crime rate went down in New York, returning to big-city life was intimidating. She moved into a building with a doorman, but that security went only so far. "I started to feel unsafe at night," she says. "It became creepy to me, and I got more nervous of being attacked on the street."

They were not unfounded fears. Although New York is among the country's 10 safest big cities, on several occasions Rosen was followed at night. She would retreat into a store or an apartment building with a doorman and seek help, often having strangers or a policeman walk her home.

"Women take more risks than they should," she says. "All of us still have this invincibility issue, that we think we really can do everything and be OK. That if we don't wear a Walkman and stay alert, we'll be OK, or if we're walking in the neighborhood we've known all our life, we'll be OK."

Rosen thought about taking self-defense classes, which her family encouraged her to do, but never got around to it. The thought of getting a dog to feel safer had never really occurred to her. Rosen noticed that most New Yorkers own small dogs, probably because of living in small apartments. But interestingly, the top three breeds licensed in the city after mixed are Rottweiler, pit bull, and German shepherd - all of which could be trained to attack.

Harry has the large frame and protective personality of a German shepherd, with the fluffy curved tail of a chow. He wasn't always as good-natured as he is today. By the time Harry was 3 months old, he was chewing up anything in his path, straining at the leash and biting at his owner.

"He was initially a very aggressive dog," Rosen says. "When they're young, you're supposed to cradle them in your arms like a baby to show them who's in charge. Harry would have none of that. I had a lot of trouble controlling him."

What it took to set Harry straight was a week of doggy boot camp, where he learned authority and discipline.

Rosen realizes that although Harry makes her feel safe, dogs are not the most reliable protection. She tells other women at the neighborhood dog run that if they have to walk their dogs in the park late at night, to do so in pairs. "They could have the most aggressive pit bull, and I would still tell them to be careful," she says.

That she did not originally intend Harry to be a guardian gives her a different perspective than that of some other women, who have come to rely on their dogs for personal security.

"If someone had a gun and had their choice of going after me or someone without a dog, they would probably choose the person without the dog," she says. "But it's not a 100 percent deterrent.

"The dog both deters people and attracts people," she says. Some people see Harry's intimidating appearance and cross the street.

Others use Harry as an excuse to sidle up and make conversation. "They're obviously not afraid of the dog," she says with mild disappointment.

Once, when she and Harry were walking down a street near her home, a man burst out of an apartment building and yelled to her, "How do you expect people to ask you out on a date when you have this big dog?"

Rosen replied, "That is exactly why I have this dog."

It actually is not what she initially had in mind when she went to get a dog, and animal experts say that is a good thing. Although most dogs do bond with their owners, and many have protective instincts, one is never sure how reliable a dog would be in a crisis situation. And the kind of breed is not an absolute indicator. "Some will sit quietly while the thief walks off with the silverware," says Perry Fina, a director at the North Shore Animal League America on Long Island.

A dog might be an "alarm dog" that concentrates all of its energy on barking and never actually attacks. Or it can be an "image dog" that takes an aggressive stance and snarls to deter attackers - but that is about it. Then there are "the all-out man stoppers," Mr. Fina says, "the working dogs who are not only capable of taking out the bad guys, but will."

Owning a man-stopper is not the safety haven it may sound like. "Training a dog to be aggressive is asking for trouble for you or your family, or anyone who comes into contact with the dog who is not out to harm you or your home," says Stephanie Shain, a director at the Humane Society of the United States. Instead, she says, owners of large or naturally aggressive dogs should teach them through obedience training that it is the owners who are in charge. Then the dogs learn to take signals from their owners about when a person is a real threat versus just delivering the mail.

For many owners, having a friendly dog who is big or looks as though it could attack is enough for them to feel safer. A woman in Riverside Park walking her Rhodesian Ridgeback, a tall dog with a strip of hair growing backward up the spine, says that even though her dog is not easily riled, "People see his fur up and think he's angry, so they stay away."

Another young woman was walking a combination pit bull and bull mastiff. The silky black creature with an oversized head, slobbering from his gravy-boat-size jaws, looks like he might repel even dog lovers, let alone potential attackers.

It turns out that, in this case, looks had better be everything. "He loves everybody," his owner says. She explains that although the sight of the dog does scare people off, she wouldn't want to rely on him for protection. "He can't wait to say hello to everybody. He never even growls."