A researcher from Charles Sturt University has warned that the region's attempts to battle the mouse plague with heavy poisons may actually be working to make future infestations stronger.
Lecturer in the school of environmental sciences, Dr Maggie Watson, told The Daily Advertiser the over-reliance on second-generation rodenticides that kill vermin almost instantly, could be affecting rodent-feeding birds of prey as well.
The concern has been raised following a survey of dead and dying birds in Western Australia's Wheatbelt, where second-generation rodenticides are common.
The birds tested for inordinately high concentrates of these poisons in their livers.
"Birds die all the time and people don't often get them tested for poison [consumption]," Dr Watson said.
"But what we do know is that in the past 20 years, there's been a huge drop-off of bird species, [including] the black-shouldered kite, which is a major rodent eating species."
Other species that are particularly susceptible are the boobook owls, barn owls, tawny frogmouths, and Australian kestrels.
While partially affected by habit loss, Dr Watson said the use of poisons has not helped to keep the populations stable.
Mainly because the second-generation baits are so powerful they have the effect of killing birds that consume rodents that have been in contact with the poison.
Without strong populations of these rodent-eating birds, Dr Watson warns, the plagues of the future are likely to be far worse.
"It's what we call 'top-down control'. They [the birds] keep control of the insects, smaller bird, and marsupial populations. Basically, they keep a lid on the populations of everything beneath them," Dr Watson said.
"If you remove them from an environment, other populations go out of control and you'll have more frequent locust and mouse plagues."
Managing the current rodent plague is thus a careful balance, and will require careful monitoring of the surrounding bird health.
"We're always going to have boom and busts of plague times in Australia," Dr Watson said.
"All we can do is ensure we have as many natural controls as possible so that we don't have to use as much rodenticide."
In order to combat the growing mouse plague, Dr Watson said a combined approach to poisoning can work.
The high-powered second-generation poisons, including brodifacoum, bromadiolone, difenacoum, difethialone, or flocoumafen, can be used safely in confined indoor areas where other animals and birds - including family pets - cannot retrieve them.
Outdoors, the softer first-generation poisons that typically kill rodents within three to eight days after consuming are the better strategy. Dr Watson recommends coumatetralyl (Racumin) or warfarin (Ratsak Double Strength).
"We need to give natural predators the space to grow in number again, which means we need to pare back the use of second-generation rodenticides to give birds space to not die before they reproduce," Dr Watson said.
Maintaining native tree species and rocky outcrops around a property will encourage birds to nest in the natural environment.
"There's no magic switch to turn the plague off," Dr Watson said.
"I understand the need to get rid of mice quickly and the economic impact they have, but we need to think in terms of the future."
For residential usage, Dr Watson said there's no beating a mousetrap with a bit of peanut butter on top.
But as for how long the current mouse plague is likely to continue, Dr Watson said it would be a matter of waiting and hoping for conditions to change.
"It depends on the weather. If it doesn't get cold, it's not going to stop," she said.
"Soils are still warm, we've had a bit of rain and it's all dependent on the food source. Mice aren't seasonal, they're food-drive.
"If there's food they'll breed as long as it's warm enough and warm for a mouse is anything down to minus-3 degrees."
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