AURORA, Colo. -- The citywide ban on pit bulls takes effect next Wednesday which means pit bull owners only have until Tuesday, Jan. 31, to license their pets.

So far, 91 dog owners have registered with the city. But at least one dog owner in Aurora is questioning how effective the new ordinance will be.

Derrick Perona said his three small dogs were attacked and killed by another dog last week while they were in their own back yard. Perona said the city of Aurora isn't doing enough to find the dog and the dog owner responsible.

"They were three very innocent animals," Perona said. "They were mauled to death within a foot of the neighbor's fence."

Now, Perona's heartbreak has turned to frustration with animal control.

"We're faced with the aggravation of the city, who says they're working on it but they haven't taken the simple step of examining any of the other dogs," Perona said.

Aurora animal control specialist Cheryl Conway said they're taking the matter seriously.

"Unfortunately, there were no witnesses and there's very little evidence," Conway said.

In the meantime, pit bulls and a few other breeds will be banned in Aurora next week --- unless owners license their pit bulls. To be licensed, owners must pay a $200 fee, get their dog spayed or neutered, have a microchip imbedded in their pet, must put a muzzle on their dogs during walks and must have a secure pen with a roof in the back yard.

Pit bulls owners must also provide proof of at least $100,000 of liability insurance and post warning signs about the dogs on their property.

"If people call and report an illegal dog, we will investigate that, and impound the animal when we find it," said Conway.

But Perona has doubts about that.

"What I have been told from the city is that they don't have the money to investigate these things. So, if you don't have the money to investigate, how are you going to have the money to regulate?" Perona said.

Other breeds that will be banned in Aurora next week are the American pit bull terrier, American bulldog, Dogo Argentino, Tosa, American Staffordshire terrier, Canary dog, Fila brasileiro, Staffordshire bull terrier, Cane Corso and Presa Mallorquin.

Residents who are unsure if their dog is a pit bull or one of the other restricted breeds may bring their dog to the animal shelter between 10 a.m. and 2 p.m., Monday through Friday. For $25, animal control staff will evaluate the animals to determine if they will fall under the new restrictions. If the animal does not meet the characteristics of one of the restricted breeds, the owner will be given a certificate approving residency.

Anyone found guilty of violating the ordinance will be subject to at least a $700 fine and up to one year in jail.

Failure to comply with the provisions will result in a revocation of the license and impoundment of the animal, the city said.

If a court finds the pit bull is in violation of the ordinance, it will be destroyed unless the owner can provide proof that it will be moved permanently out of the city limits.

For more information about the new restrictions, contact the Aurora Animal Care Division at (303) 326-8280.

To read more about the ban, click here.