The Edmonton Humane Society is no longer accepting pets that have been surrendered by their owners.
It's the first time in the society's 106-year history it has suspended admissions.
The society says it's at full capacity with homeless and abused animals, as well as pets that have already been given up by their owners.
"It's always going to be a difficult decision to not be able to help animals that are in need, but our priority is to the animals already in our care and also ... to homeless and abused animals that don't currently have a home," said spokesman Travis Grant.
The problem is an increase in the number of adult animals coming into the shelter, Grant said.
"We want to be able to provide all the animals in our care with the highest level of care and enrichment," he said. "And when we have lots of puppies and kittens, they can be placed in kennels together – but at the moment we have all of these adult animals who require more space."
Grant said the shelter will take the names and numbers of owners who want to give up their pets and let them know when there is more space.
The humane society tweeted later on Wednesday that their website was down because so many people were trying to look at the animals listed for adoption.