WESTERN Australia's isolation has led to an interesting discovery in terms of mouse control.
While mice in most parts of the world have developed a mutation to popular anti-coagulant rodenticides, research from an Edith Cowan University (ECU) honours student has found mice in the Perth metropolitan area do not possess this mutation.
This means they are easier to kill with far smaller doses of poison, which is a positive both environmentally and economically.
However, while the news of more effective controls has the broadacre cropping sector pricking up its ears, the tests were only on commercial mouse poisons, not on zinc phosphide, the only registered rodenticide for use in a farming context.
Zinc phosphide has a different mode of action in killing mice to the poison used in the ECU trials.
Trial developer Bridget Duncan said it was possible mice in other parts of Australia lacked the mutation as well.
"This is the first time these mutations have been tested on any Australian mouse population," Ms Duncan said.
"It is impossible to say with any degree of certainty if the mutations are present in our Australian mouse populations," she said.
"Generally Australian mice are relatively genetically similar, indicating they have arisen from only a few source countries.
"It is possible no Australian mice have this mutation but we are keen to build on this research and expand the geographical area for testing."
She said she was surprised at the findings of her study.
"Mice in Europe, the United States and Canada have all been found to carry this mutation and we assumed that mice in Western Australia would be the same."
"However, results told a different story, which is particularly surprising as rat poisons are much more accessible to consumers in Australia compared to other parts of the world and we assumed they would have built up resistance over time."
She said as rodents across the world developed resistance to rodenticides increasingly potent products were developed, including ones commonly used in Australia, where she said they had negative impact on local wildlife.
"Small native mammals, birds and reptiles are all killed by these potent poisons, but our research has indicated there might be no need to be so heavy handed with these chemical controls in Western Australia."
In terms of the reason why the Perth mice do not have the mutation, Ms Duncan speculated the population may have arrived from Britain prior to the mutation developing in populations elsewhere around the globe.
She also conducted research on mice in the Kimberley, which were found to be more genetically similar to populations in south-east Asia, leading to the theory they were introduced via Indonesian fishing boats.
However, again the mice in the Kimberley did not have the resistance mutation.
"They also lack resistance to common poisons so environmental managers can employ a very measured approach to population control through this method."
Ms Duncan said the next step in her research will be looking at rat populations and their response to the same poisons.