Two kiwi were found dead in Pukenui Forest, northwest of Whangārei, presumed to be killed by dogs roaming the area.
"It's a real kick in the guts to see our kiwi dying," Bevan Cramp, senior ranger at Pukenui Forest, said.
The first kiwi was found near Western Hills Quarry, Maunu, during the first week of lockdown in August.
"It looked as though the bird had been there around a week, maybe two at this stage.
"While we don't and won't be able to confirm the cause of death, based on the injuries and the number of dog sightings in the area we can say with confidence dogs are the likely culprit," Cramp explained.
The ranger says dogs have been seen roaming the eastern edge of Pukenui Forest from Whau Valley Dam to the Quarry Gardens off and on for a few years.
Recently, there have been more sightings close to the Western Hills Quarry.
The second kiwi was found by ranger Ben Lovell when he first re-entered the forest after lockdown at the start of September.
"Ben stumbled across a second kiwi located nearby the Frank Holman Memorial track in Coronation Reserve.
"There was not much left of this bird as it had been here a while."
The rangers presume the bird might have been killed around the same time as the first.
"Again due to the age of the carcass we're unable to confirm the cause of death but we are inclined to say dogs are the culprit here also."
Both birds were female and released to the forest in February this year after being reared on Motuora Island, a pest-free kiwi creche in the Hauraki Gulf.
The Pukenui rangers, Northland Regional Council staff and dog control have all tried various methods to catch these dogs to no avail.
Cramp couldn't confirm how many dogs there were but two were seen frequently.
Pukenui is a no-dog zone regardless of if they are on a lead or whether they have had aversion training or not. The dog ban also includes the Coronation Scenic Reserve off Russell Rd, the Whau Valley Dam, Barge Park, Amalin Dr and the Karanui walking tracks.
Ngaire Sullivan, coordinator for Kiwi Coast, said it was peak breeding season for kiwi at the moment and dog owners have to be extra vigilant.
"The dads are currently incubating and we have the first chicks hatching so we need really good dog control."
She said as the days are getting longer the evenings warmer, dog owners tend to exercise with their dogs around dusk – right when the kiwi wake up.
"Kiwi are free-ranging in Whangārei, they can be everywhere."
When kiwi carcasses are found in good condition the Department of Conservation can take DNA samples to trace them back to dogs which was done successfully earlier this year in Russell where a dog owner was fined $4500 after his husky killed two kiwi.
The maximum penalty is a $20,000 fine or up to three years in jail, and an order for the dogs to be destroyed.
The Pukenui Forest Trust is asking dog owners to keep their animals under control at all times.
"Fence them in, keep them in runs or chain them up when you are unable to supervise them. This is particularly important for people fortunate enough to live next to kiwi zones such as Pukenui Forest," Cramp said.
"A lot of blood, sweat and tears have been put into the forest and it's not just us rangers but also a lot of volunteers.
"The majority of people are doing the right thing. It's just a select few who are ruining it."
Pukenui Forest Trust has been operating for more than 10 years expanding its pest management infrastructure.
Since initially removing pigs and goats the regeneration of the forest is noticeable.
Mammalian pests such as rats, mustelids and possums are continuously managed and as a result the bird and invertebrate life has increased exponentially.
About 48 kiwi are living in the Pukenui Forest today, most of which have been translocated there.
However, Cramp said they knew of at least eight kiwi that have either passed through or set up territories in the forest since the first kiwi release in 2018.
At least three kiwi, including the two recent cases, have been killed by dogs.
"If this keeps happening, we're back to square one."
Pukenui Forest Trust offer free kiwi aversion training sessions for dog owners. Visit their Facebook page for more information.
Visit the Whangārei District Council website for a list of areas where dogs are allowed off-leash.