The City's Environmental Health Branch undertakes a mosquito control program in collaboration with other local authorities and the Department of Health to implement the most effective control measures possible.
The program involves:
- Monitoring and trapping of mosquitoes
- Treatment of public areas identified as breeding sources
- Investigating community complaints
- Maintaining drainage systems to prevent water pooling.
Breeding pools of water are treated with larvicides, which either kill the mosquito larvae or prevent them from developing into adults. Follow up monitoring is undertaken to ensure the effectiveness of the treatments.
When there is an increased incidence of disease and when directed by the WA Department of Health, it may be necessary to fog using adulticides. This course of action is the least effective as it only kills adult mosquitoes and does not prevent breeding. It is also the least environmentally-friendly method of control.
Mosquito numbers can vary from year to year with about every second or third year being particularly bad. This can be caused by unusual climatic conditions such as the La Nina effect that can create unusually high tides, resulting in semi-permanent pools of water in low-lying river areas.
Under normal circumstances, these areas would dry out between tides and break the mosquito breeding cycle. These pools are capable of producing continuous breeding, covering several mosquito breeding stages simultaneously. In addition, the increased flushing by tidal action has been found to dilute the active ingredient of larvicides, thereby reducing their effectiveness and longevity.
Unusually high rainfall periods can also create higher than usual water levels and increased breeding.
In addition to the foreshore and wetland mosquito control program, the City's officers treat stormwater drains that hold water. These can cause problems when summer rainfall occurs or if sprinkler overspray runs into roadside stormwater gullies.
It should be noted that a mosquito control program will not completely get rid of mosquitoes, but aims to reduce breeding to acceptable levels.
Mosquitoes can be controlled by householders in a number of ways:
Prevent breeding around your house
- Identify and remove all stagnant water sources, (eg. pot plants, cans, bottles, containers, blocked guttering etc.)
- Make sure fish ponds and swimming pools are not breeding mosquitoes. Fish ponds should be stocked with mosquito larvae feeding fish e.g. goldfish. Swimming pools should be properly maintained and have clean, chlorinated water.
Protect your home
- Place fly wire on all doors and windows
- Make sure lids are sealed on septic tanks, soakwells and leach drains
- Ensure your sewerage vent pipe has a mosquito-proof cowl, and if it is metal, make sure
- the holes have not rusted through. Your vent pipe is usually located outside, adjacent to
- your bathroom or laundry and running up the side of the house and through the roof
- Put fly wire around rainwater tank inlets and overflows
- Cut back foliage that provides homes for mosquitoes.
- Avoid exposure at dusk and early evenings
- Wear loose-fitting, long clothing outdoors
- Use a suitable personal insect repellent.