She thinks the dogs that attacked her flock of about 20 sheep and numerous lambs were on her property between 8pm and 9pm on Tuesday.
"That's when family members returned home and my granddaughter mentioned that the lambs were baaing a lot. I think they may have frightened the dogs off or they would have killed the lot," Ms Donaldson said.
The next morning a scene of slaughter greeted her when she went to see the sheep. Four sheep and a lamb had been killed and three ewes badly mauled.
"One of the ewes had half of her skull ripped off. She was still alive and it was so distressing having to put her down . . . it was horrible.
"About a third of my flock are pets and it was just awful to see all those shocking injuries and death. It must have been at least two dogs as a large sheep had been brought down and both her ears bitten off, and looking at the injuries it must have been two of them."
She had barely slept since, too worried the dogs would come back.
"It's just irresponsible owners who are failing with their obligations and letting their dogs out at night and don't know where they go. If I see a dog on my property the only thing their owners will get back are their collars."
Ms Donaldson had reported the attack to Whangarei District Council's animal control contractors, who had set up a trap to catch the dogs if they came back.
WDC health and bylaws manager Grant Couchman said there had been four attacks on stock across the district recently.
"Dogs must be controlled at all times.
"Left to run wild they can kill other animals, and are very likely to wind up dead themselves."
If the council catches a dog it makes every effort to locate its owner, but often owners do not come forward, and roaming dogs are often not chipped or registered.
"In the past three months there have been four [other] attacks on stock across the district and one case of stock worrying. Four dogs believed to be involved in the attacks were captured and put down when no owners came forward to claim them," Mr Couchman said.
"It's harsh, but that is what happens and preventing it comes down to being a good dog owner, knowing where your animal is at all times and taking proper care of it - including microchipping and registration."
Last October and November roaming dogs killed at least eight sheep and mauled another 14 - some seriously - in separate attacks on properties on Colville Rd, Dargaville.
Owners of dogs involved in a serious attack on stock can be prosecuted and dogs may be impounded and/or put down if they attack people or animals. If a dog attacks any person, stock, poultry, domestic animal or protected wildlife the owner can be prosecuted and fined up to $3000 if convicted. Owners are also liable for damage.
