Midge and mosquito information
Midge belong to the insect family Chironomidae, and are an environmental problem associated with urban wetlands in Perth. Wetlands, such as Lake Joondalup, usually have high nutrient levels. Nutrients come from a number of sources including septic tank leachate, fertilisers and detergents.
The high availability of nutrients fuels the growth of algae which often form blooms in spring and summer and subsequently go on to provide a rich food source for larval midges. At the same time, their natural predators decrease in numbers because many predatory species rely on sight and dense algal blooms limit visibility.
Midge monitoring and research at Lake Joondalup
Adult midge are usually found in higher numbers in the warmer months, causing a nuisance to the local community. The cities of Wanneroo and Joondalup in conjunction with the Department of Environment and Conservation (DEC) and Edith Cowan University (ECU) have monitoring midge at Lake Joondlaup and working to reduce numbers in an ecolologically sustainable manner, without the use of chemicals.
As the research being carried out by ECU investigates long term solutions, there are times when short term solutions such as applying a chemical pesticide may be utilised as a last resort to reduce numbers.
The decision to treat must be evidence based to verify the severity of the nuisance and elimiate subjective influences. The cities of Wanneroo and Joondalup are limited to no more than two treatments per season (one treatment contains two applications of chemical).
Tips for residents
Midge are often a nuisance in residential areas near wetlands because they are strongly attracted to lights. Residents can help reduce midge in and around their homes by taking the following steps:
- Reduce the amount of outside lighting around the house, particularly around doorways.
- Wash cars on the front lawn rather than the driveway or street.
- Use slow-release fertilisers on lawns and gardens and prevent any fertiliser spilling onto the road.
- Dispose of household waste appropriately, not down stormwater drains.
- Connect domestic wastewater plumbing systems onto the main sewer.
- Decommission unused septic tank and effluent disposal systems. (Please contact the City's Environmental Health Officers regarding any proposed septic tank and effluent disposal decommissioning.)
- Ensure matter likely to leach nutrients into the soil is removed, for example, pick up and dispose of animal faeces appropriately.
- Place sticky midge traps around the outside of the home.
- Use an insect zapper. (Please take care to clean and maintain the zapper in accordance with manufacturer's instructions.)
For more information on managing midges please contact the City of Wanneroo's Health Services on 9405 5000.
Mosquitoes can be a serious nuisance during warmer months because they generally breed in higher numbers.
Occasionally, mosquitoes spread disease-causing viruses such as Ross River, Barmah Forest and Murray Valley encephalitis virus. People travelling interstate and overseas can also be exposed to other mosquito diseases not found in WA, such as Dengue fever. This is why it is important for you to avoid mosquito bites at all times.
Follow these simple tips to help you and your family avoid mosquito bites:
- Avoid outdoor exposure to mosquitoes from dusk and the first few hours after dark
- Wear protective (long, loose-fitting) clothing when outdoors
- Use a personal repellent containing diethyl toluamide (DEET) or picaridin. The most effective and long-lasting formulations are lotions or gels. Most natural or organic repellents are not as effective as DEET or picarding
- Install insect screens on doors and windows of homes, and on enclosed outdoor recreation areas
- Use mosquito nets and mosquito-proof tents if camping/living outdoors
- Ensure infants and children are adequately protected, preferably with suitable clothing and bed nets.