Ministry of Primary Industries (MPI) confirmed Monday that the Adélie penguin found on Petone Beach last week, returned a negative result for highly pathogenic avian influenza - H5N1.
MPI chief veterinary officer Dr Mary van Andel said the ministry did not typically test seemingly healthy birds, but given the Adélie's Antarctic origin, it decided to err on the side of caution.
In February, scientists confirmed bird flu had reached the Antarctic mainland, after being detected in the wider region last year.
The Adélie penguin has been in quarantine at Wellington Zoo since 12 October.
An Adélie penguin found on Petone Beach undergoes a full health check at Wellington Zoo. Photo: Wellington Zoo
In addition to testing for bird flu, the veterinary team carried out a full health check including, x-rays, blood work, and a gastroscopy.
The zoo said initial results were reassuring, and it was working with the Department of Conservation on a release plan.
MPI also confirmed the penguin had tested negative for Newcastle Disease.