Plenty of mosquitoes to go around

By Chris Rosa

Anyone who has been outside recently can attest to the fact that the mosquitoes are out.

According to Billy Noegel. head of mosquito abatement for the Vermilion Parish Police Jury, there are more mosquitoes flying around now than any other time of the year.

The reason for so many pesky insects is because of the large amount of rain the parish received a couple of weeks ago, coupled with the recent flooding of rice fields throughout the parish.

As the second crop of rice is harvested, female rice field mosquitoes migrate several miles along canals and waterways in search of blood meals; in a few weeks, these mosquitoes will seek out sheltered areas such as sheds, barns, drain pipes, and under buildings, where they will hibernate until late January or early February.

The Police Jury’s mosquito control program is out in full force to attack the little creatures before they attack residents. The trucks are spraying at night throughout the parish, while the mosquito plane is spraying over 60,000 to 70,000 acres, which is a record amount in 2009.

Noegel said one area of the parish is getting extra spraying because of the number of rice fields in the area. He said, on the west side of the parish, there are a lot of rice fields that are flooded. The flooded fields are the perfect place for mosquitoes to lay their eggs. A female can lay 150 to 300 eggs at one time.

The spray plane is flying over pastures, rice fields and neighborhoods in hopes of killing as many mosquitoes as possible. The plane is also flying on the east side of the parish.

He said the blood sucking insects will be around for a few more weeks, which is normal for this time of year. While a cool front made its way into the area, Noegel said it will take more than cool weather to kill the insect. He said temperatures will have to drop below freezing to kill them. Temperatures are not expected to get below 60 degrees over the next week or two.

Tips to avoid mosquito bites include the four D’s:

Dusk to Dawn - Minimize outdoor activity when mosquitoes are most active, particularly between the hours of dusk and dawn.

Dress - Dress in pants and long sleeves of a light color when outside, especially in mosquito-infested areas.

DEET - The application of mosquito repellent is effective but should be conducted in compliance with the label directions. This is especially true for children. Repellent should contain DEET (N, N diethyl-m-toulamide) 30% for adults and 10% or less for children.

Drain - Check your property for containers that hold water, including rain gutters, tin cans, used tires, and trash cans.

Mosquito Biology

• Mosquitoes must have standing water to lay eggs and complete their life cycle

• Water must stand for at least 4 days

• Mosquitoes generally do not lay eggs in moving water and water with aquatic life (fish, frogs)

• From egg to adult takes 5 – 7 days in optimal conditions

• Fishermen use mosquito look a likes as bait for Utah fly fishing

• One female can lay 150 – 300 eggs at one time

The mosquito goes through four separate and distinct stages of its life cycle: Egg, Larva, Pupa, and Adult. Each of these stages can be easily recognized by its special appearance.

• Egg: Eggs are laid one at a time on damp soil that will become flooded by water or they can be laid directly on the surface of the water attached together to form “rafts”. Most eggs hatch into larvae within 48 hours.

• Larva: The larva (plural - larvae) lives in the water and comes to the surface to breathe. Larvae shed (molt) their skins four times, growing larger after each molt. Most larvae have siphon tubes for breathing and hang upside down from the water surface. The larvae feed on microorganisms and organic matter in the water. During the fourth molt the larva changes into a pupa.

• Pupa: The pupal stage is a resting, non-feeding stage of development, but pupae are mobile, responding to light changes and moving (tumble) with a flip of their tails towards the bottom or protective areas. This is the time the mosquito changes into an adult. This process is similar to the metamorphosis seen in butterflies when the butterfly develops - while in the cocoon stage - from a caterpillar into an adult butterfly. In some species this takes about two days in the summer. When development is complete, the pupal skin splits and the adult mosquito emerges.

• Adult: The newly emerged adult rests on the surface of the water for a short time to allow itself to dry and all its body parts to harden. Blood feeding and mating does not occur for a couple of days after the adults emerge. How long each stage lasts depends on both temperature and species characteristics. In the heat of the summer most mosquitoes can go from egg to adult in 5 to 7 days. Some species have naturally adapted to go through their entire life cycle in as little as four days or as long as one month.