Mosquito Population Not As Bad As Feared...Yet

Jun 14, 2012

At the end of our mild winter, there were predictions that 2012 would produce a nasty crop of mosquitoes in Michigan. For the most part, it hasn’t played out that way.

WKAR’s Scott Pohl spoke with MSU entomologist Howard Russell, who says it hasn’t been a bad year for mosquitoes yet, but that depends on your location.

HOWARD RUSSELL:  From the people I’ve talked to, for the most part, we’ve had very few mosquitoes this spring, primarily as a result of our really dry, warm spring. We didn’t have the spring melt pools that we normally would have after the snow melts, and so we had as a result of that fewer mosquitoes out biting people, and that can change quickly. If we start to get rain and pools of water standing for a week or so, we’ll have a flush of mosquitoes. It just depends on the weather at this point.

SCOTT POHL:  Aside from gee, I’m glad I’m not getting bit like I thought I might this year, what are the plusses and minuses to having a small mosquito population?

RUSSELL:  It’s all pluses as far as I’m concerned! People can enjoy their yards at night. There’s not mosquitoes biting them all day long. It’s all a plus, and then people don’t have to wear DEET and these other repellents to be outside. I can’t see a downside for having fewer mosquitoes this year.

POHL:  I guess I was thinking of Mother Nature feeding mosquitoes to something. Somebody eats mosquitoes.

RUSSELL:  Yeah, but I think they could get by without those mosquitoes, and I think most mosquitoes just die of old age or other things, too. A lot of bugs, of course, eat them, but there’s probably enough prey out there without mosquitoes, so it’s all good as far as I’m concerned.

POHL:  Is it correct that the conditions that lend themselves to a bigger mosquito population are standing pools of water and warm to hot temperatures?  Is that right?

Michigan has two types of mosquitoes

RUSSELL:  That is correct. Michigan has two types of mosquitoes, basically: we have spring mosquitoes which typically have a single generation every year, and those mosquitoes develop in vernal pools that result from snow melt in the spring; and then, we have another batch of mosquitoes called summer mosquitoes. These are mosquitoes that develop in water as it happens during the summer months. They’ll produce generation after generation, as long as there’s standing water available.

Last summer, at the end of July, we had eight inches of rain in Michigan, and ten days after that, we had swarms of mosquitoes, and those continued through September. It was horrible. There’s one little kind of mosquito that occurs in that kind of situation that will produce a generation of adults every seven or eight days when it’s 85 degrees or so. That’s a mosquito that if we get rain, a lot of people have to deal with that little bug there, and it’s an awful, terrible biter.

POHL:   So, it’s premature to say 2012 in the whole will be a low mosquito year. There’s still time.

RUSSELL: We can say that in terms of the spring and early summer, we enjoyed a relatively low level of mosquitoes. It’s too early to say how the rest of the summer is going to be. All it would take would be a week or so or rain and it could be right back with us.

POHL: As you look at summer weather projections, are you expecting that to be possible or likely?

RUSSELL: We heard Jeff Andresen, our climatologist here at Michigan State, say that he’s looking at warmer for the next 15 days, sort of above normal temperatures, and at our normal precipitation levels. If that holds, certainly, we can see an opportunity for mosquitoes to develop yet, especially in low lying areas where it doesn’t take a lot of rain to puddle up and produce a generation of mosquitoes.

POHL: Let’s hope not.

RUSSELL: I live in the swamp, so I’m hoping the mosquito population stays down and I continue to enjoy my yard and garden!