Using fake news for good in the battle to protect vulnerable birds
In a paper published today, researchers from the University of Sydney and Manaaki Whenua - Landcare Research found that tactical misinformation - what we call 'fake news' - can be used to deceive predators and double or triple the odds of successful hatching in endangered birds.
The research offers a new way to control the impact of predators such as rats, foxes and cats without employing lethal force; a method that is considered to be a 鈥榖lunt tool鈥� when it comes to reducing predator numbers.
鈥淧redators, like all foragers, must make constant decisions about what information to pursue and what information to ignore in their search for food,鈥� said the paper鈥檚 co-authors, Professor Peter Banks and Dr Catherine Price from the School of Life and Environmental Sciences.
Making good decisions requires animals to have accurate information about food, which means they are vulnerable to 鈥榝ake news鈥�.
A hedgehog investigates an odour point 鈥� caught on camera trap.
Based on the principles of decision-making theory, the 鈥榝ake news鈥� solution 鈥� developed by Professor Banks and Dr Price 鈥� works by assuming predators will give up or move on from areas that offer little reward. It also predicts they will stop searching for prey that are too hard to find when other food is available.
Working in the riverbeds of the Mackenzie Basin on New Zealand鈥檚 South Island, scientists tested the response of cats, ferrets and hedgehogs to false odour cues at nesting sites for three endangered shorebird species.
鈥淭o undermine the predators鈥� tactics, we put out 鈥榝ake news鈥� about birds鈥� nests before the birds arrived to lay their eggs. This was of a mix of bird odours typical of a nest, designed to trick predators into thinking the scent would not lead to food,鈥� Professor Banks said.
鈥淧redators were initially attracted to the odours, but within days they lost interest in the odour and stopped visiting it,鈥� Dr Price said. 鈥淲hen the birds arrived to nest, the predators weren鈥檛 interested in them.鈥�
The nest survival statistics were striking for all the nesting bird species. Compared with sites where the 鈥榝ake news鈥� hadn鈥檛 been deployed, odour treatments resulted in a 1.7-fold increase in chick production over 25鈥�35 days 鈥� and doubled or tripled the odds of successful hatching.
The scientists predict that for certain species, such as the banded dotterel, this intervention could result in a 127 percent increase in population size in 25 years of annual odour treatment.
鈥淭he experiment shows we could significantly reduce predation rates and produce population-level benefits for vulnerable prey species, without directly interfering with animals,鈥� Dr Grant Norbury, lead researcher from , said.
鈥淥ur approach cost no more to run than a traditional lethal control program, and delivered comparable conservation benefits,鈥� Dr Banks and Dr Price said.
We hope this work will encourage others to consider this approach to reduce impacts where lethal control options are too difficult or ineffective.
