People interfering with wild dog pack dynamics creates maverick behaviour that can cause stock owners more trouble than the satisfaction of picking off a single dog in the paddock is worth.
A ecologist who has studied wild dog behaviour much of his life, Roger Bilney, has watched New South Wales and Victoria’s high country change utterly in the decades he has spent studying Australia’s ecology.
Formerly a Victorian park ranger and National Parks Queensland chief ranger, he is now a sessional TAFE teacher in East Gippsland, Victoria.
“We interfere with pack structure, we’re to blame, because when you interfere with pack structure a lot of the young females have the opportunity to breed,” he said.
“A lot of people think wild dogs are just domesticated dogs gone wild, but domestic dogs simply don’t have viable populations in the wild, they die. Now we’re getting very high litter rates among wild dogs and all of the pups are in very good condition and that is purely nutrition, they’re getting fed well.
“We have to look at what we’re doing in our forestry,” said Mr Bilney. “We have more open country and a lot of feral animals, horses, pigs, deer, more forestry activities, more tracks and trails, we’re opening it up.
“If you’re shooting and trapping on the boundaries of your property you’re creating opportunity for other packs to encroach on new territory. So shooting, trapping and poisoning might make your dog problem worse,” he said.
“You’ve got your farmer standing at the fence line saying ‘I’ve got a wild dog problem, fix it’.
“But you have this very complex situation happening out there and the farmer, maybe he’s part of the problem, because if he’s shooting kangaroos or cancer-eyed cows or whatever and he’s dumping them, then he’s feeding them. One dead deer and a bitch can raise her pups on that. Peak breeding season is autumn and the time when the dog is most vulnerable, when she’s lactating is the middle of winter, that’s the peak of sambar hunting.
“There were 40,000 sambar shot last year in Victoria,” he said. “Now I’ve come across scores of carcases, you see them all the time, and that’s all food and you’re getting a peak of food at the most crucial time.
“And if the females are in good nick when they’re joined, that’s when you get big litters and if you’ve got a food source in the winter, which they have, then they’ll have healthy pups, and that’s a real worry.
“I know of an instance in which a farmer requested government departments not to drop baits on his property or even in parks beyond his boundaries because he had wild dogs, but he didn’t have a problem. Just because you’ve got wild dogs doesn’t mean there's a problem.”
Wild dogs getting bigger over time
Studies concentrated in southern New South Wales suggest most packs are working on between 100 and 150 square kilometres of territory.
Ecologist Roger Bilney said that was effectively 10 by 10 kilometres, and so there were packs of dogs everywhere. “So if you drive 100 kilometres in the bush, you might be passing through four territories,” he said.“Subordinate males are sent to patrol the perimeter of the range every two or three weeks. They patrol and defend their territory.
“A healthy dog is a killing dog, they don’t eat carrion, they’re always looking for fresh meat,” he said. And the dogs are getting bigger, where once they were 15-17 kilograms, now they’re weighing in at 21-22kg.
Packs combine to hunt large animals
Wild dogs are opportunistic by nature.
“A pack of eight dogs might go after a calf, and then the female tries to defend her calf and bang, they’ve got them both,” said scientist Roger Bilney.
“So not only are they getting food from deer carcases left by hunters and, think about a stag, who wants to cut the meat out of a stag, a seven or eight-year-old animal? The meat is almost black,” he said.
“I regularly go hunting and camping with friends.
“If there’s a shot fired we will have dogs in the camp that night.
“The dogs have learned – hunters now call it bang chow – a lot of hunters who go to remote areas, if there’s shots fired they have dogs on them.”
Sambar deer a target for dogs
Ecologist Roger Bilney said park rangers had now captured video footage of wild dog packs hunting sambar deer.
“One of the natural predators of the sambar is the tiger,” he said.
“You’ve got an animal that can share habitat with the tiger and now we’ve got a predator out there killing the sambar.
“Wild dogs are hunting them, that’s the dynamics of packs. One or two dogs might be hunting roos, or rabbits, but a pack can come together to hunt a bigger animal,” said Mr Bilney. He said that food source meant wild dogs were here to stay.
Top line predator, and adaptable
A pack of dogs capable of taking down a sambar deer make short work of an eight or 10-month-old steer or heifer and sheep are just fodder, says ecologist Roger Bilney.
“And our native animals can’t cope with such a predator.
“This is an animal that can adapt,” he said. “They’ve been known to feed on crickets and grasshoppers, right through to water buffalo and everything in between.
“It’s an incredible animal, if the dogs were dying there’d be nothing else left in the bush.
“When you reduce cover and have this top line predator, well some researchers are saying they’re not even seeing wombats anymore,” said Mr Bilney.
“They’re just gone.”
