Yes, mozzies are booming in Perth and Peel right now. Here’s why

You have not imagined it, Perth and Peel residents: the mozzies have been worse this year.

Wetland-adjacent local governments have been ramping up efforts including using drones and helicopters in their battle to curb the surge in the number of the blood-suckers.

Higher and more frequent tidal activity than in previous years has rushed huge amounts of water into wetlands across the region that, coupled with warmer weather, create prime conditions for mozzie baby-making.

The number of tidal movements above one metre in Mandurah waterways this summer has reached 26 – more than double the previous high of 11 in the summer of 2022-23. Last summer there were just two one-metre high tides.

This season alone the City of Mandurah has deployed its “mozzie chopper” 14 times to dump larvicide treatments over wetland areas that kill mosquito larvae before they mature, while the City of Bayswater has ramped up its drone treatment activity over Swan River wetland areas.

“One of the main environmental factors that drives salt marsh mosquito breeding is our local tides in the Peel Harvey Estuary, which many residential areas are located near,” the Mandurah spokeswoman said.

“When tidal surges flood big areas of wetland, this triggers the mosquito lifecycle and causes billions of larvae to hatch across the Peel Region, leading to the potential emergence of large amounts of adult mosquitoes.

“The frequency of tides peaking above one metre within the Peel waterways has been unusually high.

“Extreme high tides during January and February has led to relentless mosquito breeding, and consequently, a rise in adult mosquito activity.”

The spokeswoman said the environmental factors had impacted the success of its aerial treatments.

“The Peel Mosquito Management Group has so far treated close to 5300 hectares this season compared to just over 3600 hectares last season across 17 aerial treatments,” she said.

The Mandurah Mozzie Chopper in action.Credit: City of Mandurah/Facebook

“The treatments have been extremely effective in preventing adult mosquitoes emerging; however, despite successful reduction rates of [more than] 90 per cent, it still equates to an increased number of mosquitoes that the community will be affected by.”

The City of Bayswater offers its drone services to other Swan River councils and has been treating breeding grounds from Nedlands to Bassendean.

Chief executive Jeremy Edwards said it had been scaling up the response.

“The City is now increasing the frequency of its drone treatments, boosting its workforce, and treating the Maylands Peninsula and Golf Course areas with larvicide more frequently,” he said.

“The City is also trapping at residential properties to identify the type and source of the mosquitoes which allows us to target our treatments more effectively and is offering residents residual insecticide at a reduced cost.”

A WA Health spokeswoman said the department had not received any evidence of an increased risk of mosquito-borne diseases.

“WA Health continues to work with local governments to deliver mosquito management programs in the metropolitan area, including mosquitoes breeding in tidal and brackish wetlands along the river system,” she said.

How to fight the influx of mosquitoes

• Applying repellent with DEET, Picaridin or oil of lemon eucalyptus
• Covering up with long, loose-fitting, light-coloured clothing
• Avoiding peak mosquito times (early morning and late afternoon)
• Removing stagnant water from around the home to reduce breeding sites

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