Asa, a king penguin at the Calgary Zoo, was found dead Sunday morning after an extended battle with airsacculitis.

The penguin, one of the zoo’s eight king penguins and a participant in the zoo's penguin walk,  had been receiving medication for the respiratory infection since the beginning of 2013 and had exhibited signs of improvement.

The post-mortem examination determined Asa’s infection was too severe to respond to the medication.  Members of the zoo’s veterinary staff believe Asa’s underlying medical issues may have made her prone to breathing infections.

Asa is the second penguin to die at the Calgary Zoo.  Her death follows the December death of a gentoo penguin.  The gentoo died from internal bleeding after swallowing a stick.