As Canada’s largest zoo celebrates its 40th birthday, the zoo, which has faced increasing criticism, is trying to redefine itself.

There was cake, singing and special guests Saturday at the Toronto Zoo as it celebrated its 40th birthday.

Dr. Bill Rapley said the days of zoos simply showcasing wildlife are gone and that one of the biggest roles the modern menageries play is to help repopulate endangered species.

The zoo wants the public to know that amid the growing debate on whether or not animals should be kept in captivity at all, managers are looking at redefining the role of the zoo. 

Animal welfare activist Barry McKay said zoos need to refocus in order to survive the criticism.

“[They need to] focus primarily on animal welfare to include enough space for the individual animals which means they may not often be in sight,” he said.

“I think there's all sorts of things that zoos can do but it really boils down to being honest and putting the welfare of the animals higher up the ladder.”

Rapley said that’s a message the zoo understands. 

“We have plans to have greatly enhanced Canadian displays,” he said