Mosquitoes

Mosquitoes are small fragile insects that belong to the order Diptera, (the True Flies), family Culicidae. Mosquitoes consist of three body regions of a head, thorax and abdomen. The head of the mosquito contains the sensors, two compound eyes, and antennae to sense chemicals. The female mosquito's mouthparts consist of a long piercing-sucking proboscis, and the males head region contains feathery antennae and mouthparts that are not suitable for piercing skin.

Mosquito species vary in their breeding habits, biting behaviour, host preferences and flight range. Most mosquitoes disperse less than two kilometres from their original breeding place, others fly 5 or 10 kilometres. Some species have been reported to disperse up to 50 kilometres downwind from the larval habitats. (http://www.arbovirus.health.nsw.gov.au)

There are several different types of stimuli that attract the female mosquito to its host including carbon dioxide, body odours, air movement and heat. Mosquitoes have been around for over 30 million years and it seems that during this time, mosquitoes have been sharpening their skills so that they are now experts at locating a suitable host. (http://science.howstuffworks.com/mosquito1.htm).

The Differentiating Characteristics between female and male mosquitoes (Russell, R.C (1993)

Mosquito lifecycle

Mosquitoes require water for ¾ of their lifecyle. The mosquito transforms through four separate and distinct stages of its lifecycle: Egg, Larva, Pupa and Adult. (http://www.mosquito.org/mosquito-information/lifecycle.aspx)

A Mosquitoes Place in Nature

As irritating and annoying as the mosquito can be, it does in fact play a role in the life cycle of nature, as all species do. Both the adult mosquito and its larvae play their own role in being the food to other species of the animal kingdom as shown in the table below:

Since mosquitoes feed frequently on flower nectar, they carry pollen from flower to flower, and can pollinate flowers just as honeybees do, making adult mosquitoes not only important as they provide a food source to many other species, they also are important pollinators of flowers. (http://resources.yesican.yorku.ca/west_nile/background_mosquito3.html)

Why are Mosquitoes a Problem?

Mosquitoes spread human disease, such as Murray Valley encephalitis, Ross River and Barmah Forest virus. They have also been identified as vectors of disease to animals and have found to be responsible for infecting dogs with heartworm. For more information regarding diseases please visit the Department of Medical Entomology Website http://medent.usyd.edu.au/

Facts About Mosquitoes

• It is the Female mosquito that is responsible for "biting" you, as she needs the protein from your blood to produce eggs. She actually uses her proboscis to suck your blood, not bite!
• Mosquitoes are found all over the world, even on the Arctic continent!
• There are approximately 3,000 species of mosquitoes, 350 of these are located in Australia!
• Mosquitoes have been around for over 30 million years!
• When flying, mosquitoes beat their wings 200-600 times per second! " The hum of a mosquito is the sound of its wings beating!
• It is suggested that people with smelly feet and garlic on their breath may actually be the preferred target for a mosquito!
• Mosquitoes mate while in flight!
• Female mosquitoes can swell to over double their body size before they have even finished their meal!
• Mosquitoes can find you from up to 36 meters away using their sensory organs to detect body smell, carbon dioxide, warmth and moisture emitted from a chosen host!
• Most mosquitoes disperse less than two kilometres while others only move a few metres away from their original breeding place. However some species will disperse up to 50 kilometres downwind from the larval habitats!

Mosquito Breeding and How To Repel Them

What Attracts a mosquito to its Host?

There are some different types of stimuli that attract the female mosquito to the host including carbon dioxide, body odours, air movement and heat. Considering that mosquitoes have been around for over 30 million years it seems that during this time, mosquitoes have been honing their skills so that they are now experts at finding people to bite (http://science.howstuffworks.com/mosquito1.htm).

Council's Mosquito Surveillance & Control Program

In 1993, to emphasise its commitment to the health and comfort of the community, Parramatta City Council created an employment position for students/undergraduates (studying in the area of biological sciences) in the position of Mosquito Advisory Officer. The main purpose of this position is to promote an awareness of mosquitoes in the community and their impact on the quality of life for persons living, visiting and working in the Parramatta Council area. Encouragement of business and community support for the control of mosquitoes is also a priority. To achieve this objective, the Mosquito Advisory Officer carries out many functions and responsibilities, which include:

1. Investigating and resolving matters that involve mosquito control. This involves routine inspections of actual and potential mosquito breeding sites and investigation and resolution of complaints. The aim of this practice is to ensure that private and public premises within the Council's boundaries are operating in a manner that will provide the least likely conditions for mosquito breeding to occur.
2. Provide a specialist advisory role on and participate in such matters as:
   • Mosquito biology
   • Mosquito identification
   • The role of mosquitoes as vectors of diseases
   • The implications of mosquitoes in the urban environment
   • Mosquito control techniques
   • Mosquito surveillance and
   • Community education
3. In conjunction with the State Health Department, conduct a comprehensive survey and monitoring program involving:
   • Collection of larvae and adult specimens (See picture of mosquito trap)
   • Identification of species
   • Treatment for mosquito breeding areas
   • Compilation of statistical data
4. Treatment of mosquito breeding areas by modification of habitat or by the application of approved pesticides, namely the biological larvicide 'Vectobac'.
5. Development of policies and guidelines on mosquito control.

The Mosquito Advisory Officers also undertake a contract with the City of Canada Bay Council fulfilling the above objectives within this Local Government Area. This results in the Officers sharing their workload between both communities.

The Mosquito Trap

Above is a Mosquito Trap which is set up to catch mosquitoes. The traps are set up in the afternoon and picked up early the next morning in various sites around the Parramatta City Council area.

The two attractants used are dry ice located in the bucket at the top and a light in the battery pack. The battery pack also has a fan which blows the mosquitoes into the collection bucket.

The specimens caught are then identified and tested for possible viruses they may be carrying.

The Results

2005/2006 season results of the mosquito traps set up in the Parramatta Local Government Area

2004/2005 season results of the mosquito traps set up in the Parramatta Local Government Area

More information and contact numbers

For further information contact Parramatta City Council's Mosquito Advisory Officer on 9806 5000.