By David Hawke -- So, what's bugging you?
Been bitten by a mosquito lately? Waking up in the morning to discover you're covered in new black fly bites? Are you avoiding a visit to a marsh in order to preserve your blood supply?
If you answered "yes" to any of the above, then you are a victim of insect mythology, as very few people are ever bothered by bugs.
I can just imagine what some of you are thinking right now as you sit there scratching various itchy welts, so let me explain before you think I'm from another planet.
There are 'bugs' and there are 'true bugs'. The former is a term we throw around when perhaps we mean 'insects', whereas the latter term defines a certain group of insects. 'True bugs' have six legs like all insects do, but it is their wings that set them apart from the others. When at rest these bugs have only half their wings covered by a heavy protective layer (as opposed to beetles, whose fragile wings are entirely covered). In Latin 'hemi' means half, and 'ptera' means wing, resulting in an order of insects called Hemiptera, or True Bugs.
True bugs seldom bother us as their mouth parts are like a syringe, used primarily for sucking plant sap. Occasionally, a water boatman or backswimmer (aquatic bugs) may stick you if you handle them roughly, but for the most part they stay pretty much to themselves.
Well, if bugs aren't bugging you, what is? The answer is... flies! This is a very large group of insects, and they are called diptera ('di' means two, 'ptera' means… that's right… wing). Instead of having four wings as most flying insects do (think dragonfly... although it's not a fly, just has that in the name... maybe not a good reference after all), diptera have only two wings that are obvious. Next time you mash a mosquito take time to inspect the remains, do a little “Back Patio: CSI.”
Fly mouthparts come in a variety of shapes, each designed for the food gathering needs of that particular species. Some are made for sucking, others for lapping, and several for sponging up the good stuff. Note that flies do not have chewing or biting mouth parts, hence you cannot, technically, be bitten by a fly. Poked, injected, or ripped, yes, but not bitten. I know, moot point.
Some of our ‘favourite’ flies include mosquitos, blackflies and deer flies. If you want to find blackflies, go to a stream or creek where the water babbles and burbles over a rocky bottom. Clean, well oxygenated water flows over the larvae which are attached to the rocks; food is filtered from the water by feather-like appendages from their head.
When blackfly larvae change from underwater grub to flying adult, that change takes place underwater, within a protective case. The adult fly then rides to the surface in a bubble of air that had been trapped inside the pupal case. Adult male blackflies are very important, as they feed on plant nectar, which means, of course, they are vectors for pollen transfer -- resulting in lots of blueberries. The female blackflies eat something else, and we all know what that is!
Unlike the stream-loving blackflies, mosquitoes dislike water that moves, preferring a stagnant surface. The surface must remain dead calm in order for the larvae, called wrigglers, to reach through the surface membrane and get oxygen from above.
Once the adult flying mosquito leaves the water, the males eat plant nectar, notably from small orchids, thus ensuring cross-pollination. The nasty females are the ones that require the tasty blood meal.
Both of the above critters have sucking mouthparts, a tad different in design, but definitely lacking jaws and teeth!
Marshy areas may provide shelter for the flying adults, but the waters of a true marsh are too placid for blackflies to survive, and too choppy for mosquitoes. And, for some wonderful reason, cattail roots release an element that seems to repel these insects. Therefore, marshes should not be drained in an attempt to seek revenge on some blood-sucking flies.
Mosquitoes breed best near human dump sites. Old tires, playground pails, watering cans, tin cans with water in them… these are like resorts and spas to a mosquito. Clean up the yard and the neighbourhood, and chances are that the mosquito population will drop... or at least not get worse.
Deer flies and horse flies are a bit different in that they have scissor-like mouthparts that truly hurt if they get the chance to nip you. As the blood pours out of the wound, they soak up the liquid with a sponge-like tongue. Thankfully, deer flies spend more time buzzing around your head than actually landing and dining.
Last point: blackflies won't follow you indoors. So those bites that seem to appear overnight are either from a trapped mosquito, or Fido's little problem.
There now, don't you feel that much better about going outdoors? So what if it's over 30C -- just wear long sleeves, long pants and a mesh head piece, and apply repellent liberally... you'll hardly even notice 'em.
David’s notebook: I know, I know... black flies, mosquitos and deer flies are "just a part of summer"... but Jeez Louise do they have to be so thick?
© 2019 David J. Hawke