Mosquitos – Bli Bli and surrounding suburbs

This article was taken from the Sunshine Coast Council Website - Factsheet 21/11/2017

Mosquitos – Bli Bli and surrounding suburbs

Mosquito bites are not just a nuisance – they also have the potential to pass on disease to humans.  This information sheet is for residents of Bli Bli and adjacent suburbs outlining information on local mosquito prevalence and control measures to reduce the risk of disease transmission.
When are mosquitos a problem?

The long term trend for mosquito species abundance on the Sunshine Coast is represented in the graph below.

The high levels of mosquitos are typically recorded during December to April each year and represent increased nuisance levels, peaking in January, February and March.  This reflects the increased abundance of saltmarsh mosquitoes (Aedes vigilax) through summer and the increasing populations of freshwater breeding mosquitoes that proliferate in temporary pooling water such as flooded fields and bushland areas along watercourses during the late summer/autumn wet season. The cooler months from June to September typically have very low to no mosquitoes.

Common mosquitos encountered

The saltmarsh mosquito is the most common species throughout this area in December and January due to the proximity to the tidal breeding habitat along the Maroochy River and Petrie Creek. This species typically reach nuisance levels 7 to 10 days after full and new moon tides and are able to fly 10km+, persisting for 2-3 weeks each cycle. These tides occur every fortnight through the summer.

The freshwater mosquitos typically become the major nuisance once the summer rains begin and continue through the autumn months. Two freshwater species dominate. Aedes funereus mosquitos typically emerge from the brackish pooling water amongst the tidal swampy oak and casuarina forests and push into residential areas. Culex annulirostris mosquitos emerge from flooded paddocks and old cane fields directly north and east of the residential areas and invade adjacent residents. Whilst the summer/autumn rain events occur both species will persist and have the flight range to infiltrate surrounding areas.

Why do mosquitos bite?

Both male and female mosquitoes feed on honeydew, nectar, and plant juices. They use the sugar from these liquids for daily life. However, only female mosquitoes bite people and animals to get a blood meal. They need the protein and other components in the blood to produce their eggs.

What does Council do?

Council officers set weekly surveillance traps at locations including Bli Bli Wetlands Sanctuary and on Cook Rd on the east bank of the Maroochy River analysing data to maintain knowledge of what species are currently impacting residents. This helps us understand where the weekly issues are originating from and current status of disease vector risks to the public.

In addition the tidal breeding areas (shaded red on the map) are surveyed twice weekly to determine what the current levels and ratios are of mosquito larvae and when the optimum time/day is for targeted broad scale control work on public land. (note – Council does not treat private land. This is the responsibility of landowners).

Larvacide control work is done which targets larvae at the source with an average of over 90% reduction in potential mosquito numbers. When aerial control work is undertaken the timeframes are tight, usually 24-48 hours within a 2 week tidal cycle, and often managed around wind, wet weather and larval development susceptibility to control products.

Up to 12 larvacide treatments per season are done targeting breeding habitat locations thoughout the catchment.

Council does not spray for adult mosquitos that have recently emerged from tidal areas and bushland reserves.  Qld Health guidelines advise these are only to be considered in the event of a confirmed public health outbreak (eg. Dengue fever).

How you can better protect yourself?

Residents can play a major role in reducing the risk of mosquito disease transmission by;

  • Avoid or reduce exposure in outdoor areas at dawn and dusk during peak times
  • Wear appropriate clothing and using insect repellents when outside
  • Removing temporary or stagnant water sources around the home each week to reduce freshwater mosquito risks.

Please visit Councils website for further information on when upcoming treatments of the saltmarsh areas are scheduled and ways to better protect you and your family at home.