"Green" the penguin celebrated her 33rd birthday at Montreal's Biodome on Tuesday and that could be a record for penguins living in captivity in North America.

"If you compare that to the human life span, it's like close to 90," said the penguins' caretaker Eric Charette.

Born at the Edinburgh Zoo in 1979, Green — whose full name is Green Gen 2 — has been living at Montreal's Biodome for 20 years.

"Is it genetic? Is it the food?" veterinarian Emiko Wong asked.  "She eats the same food as everyone . . . so we don't know exactly why she's this old, but we're happy to have her.

To mark the occasion, staff at the Biodome prepared a special birthday cake only a penguin could love: the main ingredients were ice, krill and frozen fish.

Green shared it with her beau, Blue, who is 14 years her junior.

"They've been together for 12 years now," Wong said. "They're a monogamous species, so they should be together until the end."