A swarm of 2000 pink mosquitoes released in Kalamunda Shire drains by Edith Cowan University researchers this season is challenging current understandings of mosquito-baiting techniques.
The mosquitoes were released to track the effectiveness of a hormone-based baiting technique used for the past 15 years in the drains to prevent larvae from hatching.
ECU researcher Jacques Oosthuizen said the project provided useful insight into mosquitoes that survived the shire's hormone baiting as larvae.
"This project removes baited larvae from the drains and assesses how many hatch - we've found that quite a few do," he said. "We dye the hatched adult mosquitoes pink and return them to the drains, then we catch them again to give us an insight into how far the baited mosquitoes travel and their likely impact on human health."
Professor Oosthuizen said the project revealed interesting information about the way the hormone was currently used.
"Early results indicate that baiting the sediment at the bottom of the drain is more effective than baiting on the top," he said.
"This is actually contrary to the current guidelines, so that has been quite surprising."
He said while the thought of pink mosquitoes might be comical to some, the dye was quick to fade once they were released back into the wild.
"By the time we catch them again, you can only see the dye under a microscope," he said.
It is hoped the research will help increase the effectiveness of mosquito treatment techniques and tackle mosquito-borne illnesses such as Ross River Virus, Barmah Forest Virus and dog heartworm.
The project is funded by the Department of Health and implemented by the Shire of Kalamunda and researchers at ECU.