Mosquitoes

In NZ, mosquitoes are a nuisance. But mosquitoes from overseas can spread serious diseases.

Avoiding mosquitos

We can help stop these diseases spreading to NZ by stopping exotic mosquitoes from arriving and stopping them from breeding if they do arrive. Mosquitoes are often most active at dawn, around late afternoon and just after dusk.

Avoid being bitten at home

Stay in places with screens on windows and doors.
Use insect sprays when mosquitoes are around.
Use mosquito coils.
Use a mosquito net over your bed at night. You can spray this with pesticide if you wish.
Turn on air conditioning if you have it – this is very effective at keeping mosquitoes out of a room

Avoid being bitten outdoors

Use insect repellent, preferably containing diethyltoluamide (DEET). High concentrations of DEET protect better, but concentrations over 35% are not recommended if there is a choice of products available. This is because in rare cases they can cause poisoning. Other products containing 20-25% picaridin and those containing about 30% lemon eucalyptus oil (equating to about 20% para-methane-diol (PMD)) can also be used. Repellents should not be applied to wounds, irritated skin, eyes or mouth.
Wear protective clothing such as long-sleeved shirts, long pants and hats. Clothing can be treated with repellent.
Use zip-up screens on tents.
Avoid places where mossies are most active, such as swampy areas.

Note that vitamin B doesn’t prevent mosquito bites.

Facts about mosquitoes

A single female can lay over 200 eggs at a time.
Some mosquito eggs can survive outside the water for months or years.
All mosquitoes need water to complete their life cycle.
Not all species bite humans – some prefer birds, horses, or other animals.
Females require blood feeds to support egg production; males feed only on plant nectar.
Some mosquitoes can fly a long way, while others remain close to their larval habitats.
Mosquitoes do not breed in grass or shrubbery, although adults frequently rest in these areas during daylight hours.

Life cycle of a mosquito

The mosquito life cycle has 4 stages.

Egg
Mosquitoes lay their eggs in or above water. (If they’re laid above water, they won’t hatch until there is a king tide or heavy rainfall to wet them.)
Larva
The larvae hatch out and swim in water. This is when the mosquito is easiest to detect and easiest to eradicate.
Pupa
This is the resting stage between larva and adult, and is difficult to detect.
Adult
The adult is the flying, biting and egg-laying stage of the mosquito’s life cycle.

Southern Monitoring Services
Southern Monitoring Services provide lots of information on different kinds of mosquitoes.