The public plea comes after the owner of a maggot-infested and severely neglected dog was fined less than $500 in the ACT Magistrates Court earlier this month.

The dog, known as Lucky, was found by RSPCA inspectors in a skinny condition with cardiac problems, dental disease, matted hair, and open sores that had been infested with maggots.

The dog had been taken to a Tuggeranong vet by the owner's son-in-law, and was in such a state of neglect that it required immediate euthanisation, according to court documents.

The owner of the dog, Annette Banks, 49, was fined $483 including court costs and compensation, for two offences of failing to seek veterinary care. She was also convicted for an offence of neglect although she was not restricted from pet ownership.

RSPCA chief executive Tammy Ven Dange said the penalties for animal abuse in the territory were "unsatisfactory" and harsher measures needed to be introduced.

"It is appalling for an owner to clearly show no care for the wellbeing of their pet in such a way that their animal has suffered greatly," she said.

"To know that an individual who was just convicted of cruelty against animals can immediately get another animal is ridiculous."

The RSPCA petition, which is registered with Change.org, also refers to previous cases such as an 86-year-old man who was caught beating a possum with a pole and escaped conviction.

The petition also referred to a woman who was fined $800 in February for starving and neglecting her dogs who were found with matted hair, overgrown nails, faecal balls had been left to accumulate, skin damage, and ruptured eardrums.

Last month, a woman was fined $300 and banned from pet ownership for two years for neglecting an underweight dog found with clumped fur, a discharge coming from its eyes and a large scar on its back.

As of lunchtime on Wednesday, almost 300 people had signed the petition since it was launched on Wednesday morning, with some Canberrans leaving comments of support.

"Petitions are not always the most effective way to get people attention and we know that but if the numbers are higher enough it may be able to get out message across to the government," Ms ven Dange said.

"If the magistrates don't apply penalties anywhere close the maximums already, what difference does it make if we increase the penalties in the legislation?"

Ms Ven Dange said her organisation had more than 20 cases currently before the courts and the lack of outcomes was frustrating and costly.

"It's just appalling to see the amount of resources we put in preparing a case for prosecution lasting eight or nine months, only for a penalty that is nothing more than a slap on the hand," she said.

"Just about every other day our inspectors bring in another neglected, abused or abandoned animal."

- with Christopher Knaus and Michael Inman