Monday, September 17, 2012

Midges- part two

I would like to expand upon my midge post from last week.  I received an email that suggested that I clarify some finer points of the label "midge" and I agree that it is a good idea.  While I tagged the post with Chironomid, I didn't mention it specifically in the blog post itself and I should have.  So come along for a taxonomy tour.

There are biting midges and non-biting midges.  Last week's post was about non-biting midges.  While all midges are in the order Diptera (which includes flies, mosquitoes and midges), the biting midges fall into the Ceratopogonidae family and the non-biting midges fall into the Chironomidae family (click on links to see images).

Ceratopogonids are called biting midges, but more often around here, no-see-ums.  No-see-ums can cause painful bites to people who spend time outdoors.  Bites may cause painful lesions for some.  Adults are gray and tiny (less than 1/8 an inch long) with long antennae and well-developed mouthparts.  Only the females take a blood meal.

It is also possible for Chironmid midges to get confused with the Culicidae family (which are the mosquitoes).  Both groups are delicate looking insects with slender bodies and long legs.  Both Chironomid and mosquito males have feathery antennae, so may look very similiar.  Mosquitoes have an elongated proboscis (mouthpart) and scales on the veins of their wings which helps to differentiate them from other insects in the order Diptera.

Hope that clarifies a bit more of what a midge may and may not be.  As always, if you ever have a question on identification of an insect, collect a sample and either send it to me or take it to your local Extension office.

Friday, September 14, 2012


I've been getting reports of the mass emergence of midges from various lakes this week.  Midges are non-biting insects that are related to flies.  The species that I have seen look similar to mosquitoes, but they do not have elongated biting mouthparts.  They have slender bodies, long legs and males have feathery antennae.

The larvae of midges develop in water.  They can be found in ditches, ponds and lakes rich in organic matter, streams or rivers.  The presence or absence of certain midge species can sometimes be used as indicators for water quality.

Midges can emerge in very large numbers.  The adults are weak fliers but are attracted to lights.  Lights often attract them to inhabited areas where they become a nuisance to homeowners or businesses.  Swarms can become very dense and make outdoor activities difficult to enjoy.

Tips for avoiding midges:

  1. Turn off outdoor lights or switch to bulbs that are less attractive to insects.
  2. Drain or reduce water in lakes where midges emerge to kill off overwintering populations of larvae.
  3. Bacillus thuringiensis var. kurstaki works on midge and mosquito larvae (read product label for application rates).
If you're dealing with a mass emergence of midges, take heart....emergence only last a couple of weeks!