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.
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Ecologist at the Institute for Land, Water and Society in Albury-Wodonga Maggie Watson said the over-reliance on second-generation rodenticides that kill vermin almost instantly, could be affecting rodent-feeding birds of prey as well.
As part of the funding package, the government is seeking approval for the use of bromadiolone, a highly lethal second-generation poison.
Dr Watson believes the poison is likely to affect not only the mouse population but other species including rodent-feeding birds of prey.
The concern has been raised following a survey of dead and dying birds in Western Australia's Wheatbelt, where second-generation rodenticides are common.
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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.
"It's what we call 'top-down control'. They [the birds] keep control of the insects, smaller birds, 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."
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, Dr Watson recommends coumatetralyl (Racumin) or warfarin (Ratsak Double Strength).