Order: Diptera (Flies)
Chandara asks: “I’ve always heard that if it doesn’t get/stay cold enough over the winter that the mosquitoes will be especially bad the following summer. Is that true? If so, we’re in trouble!”
If you’re not in the midWest, Ohio area, you might have actually had a winter this year. If you do live here, then you probably know that we have completely bypassed winter, most of spring and are heading into Summer…in March. As with most plants in temperate zones such as this, insects need some down time too. They typically get this during the winter when the days are shorter and cooler. Depending upon the species will determine how they get through these “dark” times.
Some will form pupae and hang out in their preferred homes. You will often find the gorgeous cecropia moths hanging out in this stage dangling from shrubs and trees. Don’t hurt them! They’re gorgeous. Likewise, many species overwinter as larvae in the soil.
Now, to answer Chandara’s question regarding mosquitoes….I would have to say Yes…and No.
Not every species will react to the lack of cold the same way. Some species need it and will not experience full diapause without those temperature cues. However, diapause is influenced by more than just temperatures. The day/night exposure (photoperiod) is probably the most important component affecting diapause. So, just because it doesn’t get cold enough, doesn’t mean the insects will not enter diapause. Additionally, there are strong maternal effects which can regulate an individuals photoperiod response as well. As if these little buggers weren’t complicated enough!
Aside from the adult stage, all mosquito life stages are aquatic and many (if not most) species overwinter as eggs in lakes or other small pools of water. Some species will overwinter as adults by hanging out in places which do not get extremely cold. Here’s the thing though…these overwintering adults are not the primary populations the following season. Those will come from the eggs and larvae.
So it basically boils down to this…the species which need to experience that temperature-related down time during the winter will not thrive during these next seasons. The species which are more tolerant of temperature related shifts and/or are more reliant upon other mechanisms (ex: photoperiod and maternal, etc) will probably do just fine, possibly even better than normal, because there were no intense cold periods which would thin out their populations. Some species will be flying around like crazy and some won’t.
Just remember to keep your DEET handy. I would also recommend getting a jump start on flea and tick treatments as well heartworm preventive medicines for outdoor venturing pets.