A study has suggested exposure to agricultural chemicals in South Australian cropping land could explain poor health in a native lizard species.

Researchers from the University of Sydney, University of Western Australia and the CSIRO studied two populations of sleepy lizards, also called shingleback lizards, and found that a population living near an intensive cropping region was on average smaller, and more likely to have anaemia, than a similar population living in away from farms.

The study took place in 2010 in the Murray-Mallee of South Australia, about 200 kilometres north-east of Adelaide, with the two study populations being separated by the Murray River.

During that time, farmers were trying to control an outbreak of mice which were damaging crops.

Researcher Dr David Phalen, from the University of Sydney, says the results of the physical examinations and blood analyses suggest mouse bait could have caused the widespread anaemia in the lizards.

But further work needs to be done to be certain that chemicals are the root cause of the anaemic lizards.

"We've got strong evidence that they've been exposed to some sort of toxin, and we know that some of the chemicals they've been exposed to can cause these kinds of problems.

"That's all circumstantial evidence. The only way you can prove that would be [further testing]."

He says the findings are important because lizards are good indicator of the overall health of their immediate environment, much like canaries in a mine shaft are. Listen Duration: 4 minutes 56 seconds 4 m 56 s Listen Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. The University of Sydney's Dr David Phalen explains why scientists think exposure to certain types of agricultural chemicals have caused anaemia in lizards. ( Clint Jasper ) Download 2.3 MB

"Reptiles don't move around very much and generally stay in the same area for a long time.

"Some lizards can stay in the same place for more than 50 years and are thus exposed to chemicals and other things in their environment for their whole life," he said.

"We think reptiles are good animals to monitor for what's going on in the environment, and if they're exposed to chemicals they're likely to have an adverse affect.

"They're easily captured and easily sampled.

"We can detect problems in them before other animals in the environment start to show signs."



