A small group of animal advocates gathered outside the Edmonton Humane Society on Saturday to call for changes to Alberta's Animal Protection Act. Their call comes after three rescue cats en route to the shelter were forgotten inside a vehicle for 22 days this spring.

According to the society, a team brought the animals to the Edmonton shelter from another agency on March 27, but three cats were overlooked when the vehicle was unloaded. They weren't discovered until April 18, when staff were preparing for another animal transfer.

The society said the cats were dehydrated, hungry and had minor urine burns on their paws, but suffered no major injuries or illnesses. The cats have since recovered and have been adopted in Calgary.

Michelle Elfstedt, who organized Saturday's event, said Alberta's Animal Protection Act needs to be amended to prevent something like this from happening again.

"The B.C. Animal Protection Act actually has a section in there [on] how ... the humane societies and rescues have to deal with transport of animals," she said.

"There's nothing like that in the Alberta Animal Protection Act and we feel like there should be to hold some sort of standard to the EHS, because the EHS is actually not accountable to anybody."

Jaime Caza, director of resource development for the Edmonton Humane Society, said Saturday that the organization is in the process of seeking a third party investigation into what went wrong to ensure it doesn't happen again.

She said the EHS has also asked the Solicitor General to appoint someone to the investigation. The outcome of the investigation will be made public, she added.

"As individuals that commit their lives to serving animal welfare, of course this has been a very difficult situation for all of us. But we are committed to working through this," Caza said.

"We have been serving the community for 110 years and we take that very seriously. We are committed to investigating the situation."