Inflatable tube men—those wacky, wriggling figures that tower near car dealerships and mattress stores—are typically designed to grab attention. But scientists in Australia have used them for the opposite purpose: to scare away unwanted onlookers. A new study suggests the unpredictable movements of these dancing eyesores could keep wild dingoes from killing livestock.
“It’s exciting … to see real [alternatives] to lethal management of dingoes,” says Colleen St. Clair, a conservation biologist of the University of Alberta, Edmonton, who was not involved in the study. The approach, she says, might not just save farm animals—but the dingoes themselves.
Dingoes have been a bane to Australian farmers for centuries. The medium-size canines often sneak into ranches, killing mostly sheep, but also some cattle and goats. Official reports, though inconsistent, suggest the wild canines kill thousands of farm animals and cause up to $60 million in damages every year.
To confront the problem, farmers and the government have long relied on poisoning and shooting. These inexpensive solutions get rid of some nuisance dogs in the short term, but experts say they could cause more damage in the long term. That’s because apex predators such as dingoes affect the whole of the food chain, from animals to plants: When they hunt kangaroos, for example, they keep populations from exploding and overgrazing the landscape. Lethal control also fractures wild dingo family units, increasing attacks from reckless young dingoes.
Farmers and researchers have tried to drive dingoes away with nonlethal alternatives like high-pitched sounds and fences made of colorful flags, but the dogs quickly get used to these temporary solutions. “They’re very intelligent,” says Bradley Smith, an animal behaviorist at Central Queensland University, Adelaide. “It’s hard to scare them for too long.”
Motivated in part by Suzanne Stone, a wolf conservationist who used a tube man to scare wolves away at a ranch in Oregon, Smith and colleagues decided to test the approach scientifically in Australia. Smith enlisted an engineer to rig up a “Fred-a-Scare” at a Melbourne dingo sanctuary. The team plonked the 4-meter-tall, yellow, grinning tube man in the sanctuary exercise yard near a bowl of dry dog food. Then the team invited breeding pairs of hungry dingoes into the fenced yard downhill from an out-of-sight Fred. (Dingoes typically travel in pairs or families.) In a separate experiment, the researchers replaced the tube man with a speaker that played gunshot noises.
Fred was a hit—at least with the scientists. After rounding a corner and seeing the dancing tube man for the first time, nine of the 12 dingoes ran away in fear, compared with only one that ran from the gunshots, the team reports in Pacific Conservation Biology. What’s more, Fred’s scares were long-lasting: Over 3 days of testing, the tube man successfully protected the food in 75% of trials. “When you have sound, the dingoes will flinch. They’re a bit nervous but they don’t run away,” Smith says. “But the wavy man, boy, they bolted.”
Stone says she’s excited to see someone test this deterrent with dingoes— and she hopes to see conservationists apply the results elsewhere. Still, even though tube men have helped deter wolves for 2 years in Oregon, Stone is not convinced they’re a practical solution for free-range livestock in Australia. Each tube man requires roughly 1000 watts—about the same as a dishwasher—and can only protect a small area. That makes the approach better suited for guarding animals on small farms and campers’ food at campgrounds, she argues.
And although St. Clair says she is “genuinely pleased” with the findings, she adds that it’s still unclear whether the dingoes will stop fearing tube men after a few days of exposure. Instead, she says, farmers might want to combine or rotate many deterrents to keep the predators guessing.
sciencemag.org, 20 October 2020