A kiwi death on former world tennis star Thomas Muster's property in the Bay of Islands is a ''wake-up call'' to dog owners to keep their pets under control, a land care group says.

The young male Northland brown kiwi was discovered by a group of dog walkers on Russell's Long Beach on June 9, but news of the death has only emerged in recent days.

One of the walkers rang the Department of Conservation's emergency hotline to report the dead bird.

DOC biodiversity ranger Cinzia Vestena said the bird did not show obvious signs of an attack such as bleeding or lacerations, but an autopsy by Massey University experts found injuries consistent with a dog attack.

That included bruising, internal bleeding, torn soft tissues, and multiple fractures to the sternum, ribs, pelvis and spine.

The woman who discovered the dead bird said it was ''really upsetting'' to find the kiwi had been killed by a dog. She called on dog-owners to keep their pets under control at all times.

''I'm really concerned that less responsible dog-owners are not keeping their animals under control, as this may impact on how and where the majority of us responsible dog-owners can exercise their animals," the woman, who did not want her name used, said.

Tree-felling was under way on the property where the kiwi was found.

Property manager Terry Storey said he knew kiwi were nesting near the eastern end of Long Beach, so the landowner had employed kiwi handler Steve McManus and his kiwi detector dog to find out where the birds were before felling started.

Storey was ''absolutely gutted'' to learn one of the kiwi he'd been monitoring was dead because of an uncontrolled dog.

The landowner is understood to be former world number one tennis player Thomas Muster of Austria.

Russell Landcare Trust chairman David McKenzie said most dog owners act responsibly but some steadfastly refuse to believe their pets could kill a kiwi.

''This dead animal is the hard evidence they appear not to want to face up to. It should act as a wake-up call,'' he said.

News of the death comes as the Far North District Council is about to start consulting on a rewritten version of its Dog Management Policy and Bylaw.

Leonie Excel, spokeswoman for dog-owner lobby group Bay of Islands Watchdogs, said the group had been urging members to take care and not let their pets off lead in areas where kiwi might be present.

She was pleased the ''8am Long Beach ladies'' had found the dead bird and reported it immediately. The group was encouraging people who saw a wandering dog to catch it if it was safe to do so, tie it up at home and post a photo of the animal on social media until the owner could be found.

Last week two fox terriers were seen running free in Coronation Reserve, in Whangarei's Western Hills, in an area where 12 adult kiwi were released into the forest in March.

A DOC investigation into the death of six kiwi on the Purerua Peninsula, in the northern Bay of Islands, in February is continuing. Samples of dog saliva were taken from the birds for DNA analysis.

- NZ Herald.