Flooding & Mosquitoes

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First come the floods, then come the mosquitoes



After a relatively dry summer in South Carolina that held mosquitoes to low numbers, recent historic floods have prompted a huge population explosion. All mosquitoes need water to start their life cycle, and eggs are laid individually or in clusters called ‘rafts’ on the surface of water or near it. The larvae hatch and develop under water and feed on organic debris. The water must be stagnate so that the larvae and pupae can penetrate the surface with their breathing tubes to get oxygen. If the water is moving they cannot survive. Small pools of water, such as in buckets, tires, bird baths, and mud puddles are ideal for breeding mosquitoes because there’s not a lot of movement and very few predators. If water sources are not available for mosquitoes to lay their eggs, they will find low-lying, flood-prone areas to deposit them. The eggs sit dormant in those areas until water pools up and prompts them to hatch.


In ideal conditions mosquito larvae can turn into blood sucking adults in about a week. Because it is late fall and temperatures are cooler, it has taken two to three weeks for the adult mosquitoes to emerge and now many areas around the state are experiencing lots of activity. County mosquito control programs are receiving a high rate of calls, but simply getting to some areas is a challenge because several roads have still not been repaired.. They are targeting the most active areas by conducting treatments using trucks and helicopters to kill adult mosquitoes. They also treat breeding areas such as ditches, retaining ponds, and flood spill zones with growth regulators to kill the larvae. This helps reduce the populations in municipal and public areas, but may not impact mosquitoes living and breeding in your back yard.


As with many seasonal pests, mosquitoes are dependent upon certain temperatures for their survival. Their populations tend to crash after the first heavy frost occurs in late fall or early winter. The longer temperatures stay above freezing, the longer the season lasts. Hopefully within the next couple of weeks a heavy frost event will cause the mosquitoes to go away but what do we do in the mean time? Here are some tips to help deal with mosquitoes while we wait:

  • One of the most important things to do is to eliminate as much standing water as possible. Dump out unused flower pots, wheel barrows, buckets, kiddy pools, bird baths, and anything else you can find that is holding water. Inspect tarps being used to cover pools, boats, firewood, and anything else for water pockets and eliminate them. Sometimes water can be pooled in a crease and not easily seen.


  • Make sure gutters are not clogged and working properly.


  • Make sure windows and doors have screens on them.


  • Your crawlspace may still have standing water from the floods—this needs to be corrected as soon as possible. If you cannot inspect this area yourself call Terminix for a free inspection.


  • When you go outdoors wear long pants and long sleeves to help reduce bites. Also, use insect repellent. Those that contain DEET seem to be the most effective.


  • Make sure your dogs and cats are treated for the prevention of heartworm – which is also spread by mosquitoes.


  • Call Terminix for a free inspection and estimate for an ongoing mosquito management service. Typically treatments are made once a month from April through October. If you sign up now, a late season treatment can be made to knock down the population for the rest of the year, and then service will pick back up at the beginning of next season.