The Calgary Zoo says one of its Humboldt penguins has died after it became ill on the weekend.

The zoo posted the sad news on its Facebook page on Tuesday saying that Guillermo died after a brief illness.

The three-year-old penguin came to the Calgary Zoo from Rosamond Gifford Zoo in Syracuse in December 2011.

The zoo says keepers noticed that Guillermo was lethargic and didn’t have an appetite and moved him to the health centre when he failed to respond to treatment.

The penguin passed away on Monday and officials say he was in good health before he suddenly became ill on the weekend.

The zoo has done a post mortem examination to try and determine a cause of death but says the results won’t be available until some time next week.