The Department of Conservation is investigating after a protected kererū was found shot dead by a crossbow in Wainuiomata near Lower Hutt.
Hayden Jones of Lower Hutt Kererū Rescue was notified of the dead bird by a member of the public on Monday, and he picked it up and provided it to DOC yesterday.
The crossbow bolt, which appeared to be a smaller type used in one-hand crossbows, was also provided to DOC for examination.
He said he believes the bird may have been dead for about a week before it was found.
Jones said an "extremely sick individual" was likely to blame, and that it is "something that shouldn't be happening to our native species".
"Most people know what kererū are and that they're native species - being a native species, it is an offence to harm them in any way," he said.
"Leave our native species alone."
DOC operations manager Angus Hulme-Moir confirmed the agency is investigating, and said his organisation is "saddened by this senseless act of wanton destruction".
"Kererū are an absolutely protected species under the Wildlife Act and kererū are still in some trouble nationally," Hulme-Moir said.
"DOC is pleased that in some places, like the Wellington region, kererū are recovering and becoming more common in suburban areas.
"Community efforts of pest control have contributed to an increase in numbers locally."
Under the Wildlife and Conservation Act, the maximum penalty for hurting or killing a kererū is up to two years in prison, a $100,000 fine, or both.
Anyone with information about the shooting or harming of protected wildlife can confidentially report it by calling 0800 DOC HOT (0800 362 468).