Department of Conservation rangers are hoping DNA testing will lead them to a kiwi killer on the loose near Kerikeri.
Seven kiwi were found dead last month in the Wharau Road area, off Kerikeri Inlet Road, all having died as the result of dog attacks. At least three more birds are believed to have died.
DOC and the Far North District Council have been trying to identify and catch the dog or dogs responsible. Live dog traps have been set, so far without success, and property visits have located 15 previously unknown dogs.
Ranger Adrian Walker said DOC was now awaiting the results of DNA tests. Hair samples had been taken from four dogs on Wharau Road to see if they matched saliva found on the kiwi. The results would be known within days.
DOC had carried out patrols on Wharau Road, and the local Landcare group, along with concerned land owners, had been reporting any wandering dogs.
No new deaths had been reported in the Wharau Road area, possibly as a result of people keeping their dogs tied up since extensive media reports earlier in July, but since then at least five more kiwi had been killed by dogs in the wider Bay of Islands. Those deaths occurred at Te Puna Inlet, Okaihau, Oromahoe, Puketi Forest and Golf View Road, in urban Kerikeri. Two kiwi had been killed by cars, at Rangitane and Opito Bay, in the same period.
Mr Walker said DOC had had "excellent co-operation" with Far North District Council animal control officers in its bid to end the attacks, adding that the Wharau Road deaths were the worst spate of kiwi killings in the Mid North since a single dog dumped in Waitangi Forest killed an estimated 500 birds over a six-week period in 1987.
Mr Walker urged dog owners to know where their animals were at all times.
"Keep them supervised and properly chained up or kennelled at all times. Don't give them a chance to run off down the back of the lifestyle block and put kiwi at risk," he said.
Kiwi aversion training was helpful but was not a silver bullet, he added.
A council spokesman said animal control staff had been assisting DOC by setting dog traps, calling in at various properties to get dogs on record, following up on leads, helping with DNA testing, and educating Wharau Road residents about responsible dog ownership.