Dog-Dog Aggression Off Leash

Why Dogs Are Aggressive toward Other Dogs

Some aggression may be a normal, adaptive behavior in virtually all animal species and domestic dogs are no exception. Luckily, there are a number of things you can do to minimize both the frequency and intensity of dog-dog aggression.

Dog Park Fighting

Dogs can be bullies, protective about toys or food, or socially uncomfortable, and any of these issues can make for regular excitement at the dog park. Dogs don’t automatically get along with every dog they meet, just like we don’t get along with every single person we come across.

Most importantly, keep in mind that dog parks don’t suit every dog. Many dogs thrive on social time with other dogs, but some need their personal space and that’s okay, too. If that’s your dog, bypass the dog park and instead use hiking trails, beaches, or other less-crowded spaces for your dog’s exercise.

What You Can Do

Be honest with yourself: is your dog truly a good dog park candidate? Are they socially versed and friendly with dogs of all sizes, breeds, and temperament, and loves to play and wrestle?

Not sure if your dog is right for the dog park? Here’s what to look out for:

Bullying behavior includes jumping on top of, pinning down, or continually chasing and nipping other dogs. If your dog usually plays well but seems to target certain dogs for bullying, give them a time-out whenever it happens i.e. leash them up for a couple of minutes or, if they do it again, take them home.

Protectiveness of toys. If your dog fights over toys, you can manage the problem with good situational awareness. Actively supervise your dog’s playtime and look out for balls or Frisbees so you can call him away from those.

Social discomfort. If your dog is socially uncomfortable, he can possibly learn to love the dog park with carefully planned exposure. Take your dog there at times when you know it will be less crowded and keep the sessions short. If your dog ever seems uncomfortable or scared, engage them in some solitary play with a toy and leave the park when they are happy.

If the behavior in any of these situations continues despite your careful supervision and active management, or your dog gets into serious fights or inflicts real damage, they’re obviously not a good dog park candidate.


  • Spay or neuter your dog. This is very important, especially with intact male dogs, who are at higher risk of fighting with other males.
  • If a fight breaks out, keep your hands away from the dogs’ heads and mouths. Don’t grab collars, instead try interrupting the dogs by making noise, using water, or covering the dogs’ heads with a blanket or jacket to distract them.
  • Make sure your dog is up-to-date on vaccinations, flea prevention, and deworming treatment.
  • The SF SPCA offers off-leash classes – check our website for availability.
  • If you can’t take a class and your own efforts aren’t successful, contact SF SPCA’s board-certified veterinary behavior specialist. Don’t live in the Bay Area? Search locally for a veterinary behavior specialist (Dip ACVB), a Certified Applied Animal Behaviorist (CAAB or ACAAB), or a Certified Professional Dog Trainer (CPDT).

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