The wayward emperor penguin was released in sub-Antarctic waters south of Stewart Island yesterday more than two months after coming ashore on Pekapeka Beach near Wellington.

However, according to a tracking device, he is swimming the wrong way and heading back to New Zealand.

Happy Feet, the first of his kind seen in New Zealand in 44 years, was nursed back to health at Wellington Zoo, winning the hearts of Kiwis and animal lovers worldwide in the process.

Returned to good fitness and fitted with a GPS tracking device, Happy Feet had an "excellent chance" of meeting other adolescent penguins and finding his way back to Antarctica, experts say.

Online monitoring on ourfarsouth.org seems to show that he has turned in a north-east direction and is heading back to New Zealand.

Wellington Zoo vet Lisa Argilla, who is credited with saving the penguin's life, has said some deviations in his swimming course were to be expected.