Three Madagascan radiated tortoises were pinched from the zoo in June and September 2011, and in February 2016.

The third critically endangered reptile was returned within days after being dumped at a police station in a backpack.

But the other two were missing for more than seven years until police responded last month to reports of a burglary at Mai Huy Vu Vo's Girrawheen home, where they allegedly found one of the animals in his backyard.

Days later, they found the other tortoise at a 35-year-old woman's Greenwood house.

She was charged with trespass and stealing - so, according to police, one of the tortoises was stolen twice.

Vo was charged with three counts of possessing stolen or unlawfully obtained property, and tried to enter guilty pleas at his first court appearance in Joondalup Magistrates Court on Friday.

A professional interpreter had been arranged but fell through, so his multilingual lawyer Vinh Nguyen stepped in.

Vo gave a lengthy response in Vietnamese when asked how he would plea, and when Magistrate Laurence inquired about what he'd said, Mr Nguyen responded: "Guilty. He didn't know that it was stolen from Perth Zoo."

The lawyer said his client wanted the matter dealt with as expeditiously as possible, but the magistrate refused to accept the pleas without a professional interpreter.

Vo will return to court on November 2.

Australian Associated Press