Mosquitos love the rising lake waters

Better get used to the annoying buzz of the mosquito.

Better get used to the annoying buzz of the mosquito.

Like the insect itself, its eggs are particularly stubborn, remaining viable for years after they were laid, until the spot they’re on is flooded again, and provides the habitat they require to reach the next stage of life.

So, with this year’s flooding all around the edge of Okanagan Lake, land that hasn’t had water on it for years is suddenly ideal mosquito habitat and even old eggs are coming to life.

Kevin Touchet, manager, environmental health with Interior Health, warns it could be a nasty mosquito year, particularly for the aedes or floodwater mosquito.

Although some say their eggs can hatch 20 years after first being laid, if conditions are right, Touchet says there’s a decrease in viability after a time. However, certainly eggs laid a few years ago will still be viable and could hatch this year with high water in valley lakes inundating new ground.

“Whenever there’s high water there are more hatches of mosquitoes because there’s more breeding ground available for them,” he explained.

The good news is—that is not the species of mosquito that is of particular concern to Interior Health because it doesn’t usually carry the West Nile virus.

The culex tarsalis mosquito, which prefers stagnant water with lots of organic matter such as swamps, is the common carrier of West Nile virus.

However, the culex pipiens or house mosquito is also a carrier and its numbers can generally be reduced by being vigilant in your own backyard.

Empty the birdbath every few days and keep water from collecting and staying in flower pot saucers, eavestroughs, old tires, pool liners, children’s toys, and wherever water can pool up, he advises.

Culex species tend to hatch during warmer weather, so August is a time for more concern than June. “The key to preventing West Nile virus is in your own backyard,” said Touchet. “We’re not trying to eliminate mosquitoes, so people need to protect themselves with window screens, and by avoiding outdoor activities when mosquitoes are most active, at dusk and dawn. They prefer dark clothing, so avoid that.”

Only the females suck blood because they require a blood meal in order to lay their eggs.

Interior Health is working with local government to conduct larviciding of known breeding sites, and IH staff are doing some mosquito trapping and monitoring for the virus.

Both culex species prefer birds although they will go after humans, while the aedes prefers humans.

WNV is a disease of birds that is spread by mosquitoes, so the insect would have to bite a bird and then a human to spread the disease. It’s usually fatal to corvids such as jays, blackbirds and magpies,

There is an online site for reporting dead corvids but Touchet said they are not collecting birds any more because they know that the virus is in the Okanagan now.

If you discover a dead corvid, wear gloves to touch it and double bag it before disposal. Report your find to  http://westnile.bccdc.org.

 

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