Shortly after my arrival at MSU in the late summer of 2002, I discovered dozens of dead flies piling up in the light fixtures and on the window sills every day in my office on the 5th floor of Cobleigh Hall.  This situation was rather disconcerting, so I decided to make it my mission to call Facilities Services and find out what can be done to reduce or eliminate this infestation.

This led me through three different phone transfers until I was put in touch with Jon Ford, Manager of Environmental Services. Mr. Ford provided a plethora of interesting (but discouraging) information about the fly situation. If you do NOT want to read all the unpleasant details, then stop reading this document now!

  1. The flies are "Cluster Flies" (Diptera: Calliphoridae, Pollenia rudis)*. Cluster Flies are distinguishable from other common flies by the short gold colored hairs on their thorax (you have to look pretty closely). Their life cycle includes a larval stage in which they live in the soil as parasites of common earthworms. When near maturity, the larvae leave the earthworm host (gack!) and emerge from the soil as adult flies. Persistent local lore not withstanding, the larvae do NOT breed in the air handling system of Cobleigh.

  2. The adult flies congregate in warm areas late in the afternoon, particularly in the autumn season, and try to find nooks and crannies to crawl into to keep warm. Some adults will hibernate through the winter in such nooks, then start the life cycle of the Cluster Fly species again in the spring.

  3. Cobleigh Hall is chock full of gaps, cracks, and holes, especially under the exterior "hoods" over each window. Apparently every window has a 1/4" to 1/2" gap that goes directly into the space above the suspended ceilings. You can guess how attractive this is to the Cluster Flies as they seek warm places to hide.

  4. cluster flyWith all the deferred maintenance on campus it is extremely unlikely that all the gaps and cracks in Cobleigh will be fixed anytime soon. Mr. Ford says the only way to eliminate the gaps is to tear down and rebuild the building (now THAT'S an idea...). One can only wonder about the energy inefficiency of the current situation, too.

  5. Montana Hall is the other building on campus that was seriously infested with the Cluster Fly problem. Thus, the problem is well-known even at the highest levels of the campus administration, so complaining up-the-line probably won't do any good.  The windows in Montana Hall were replaced in 2002-2003 and reports appear to confirm that the fly infestation in that building has been eliminated now.

  6. Mr. Ford has a pest control contractor who will come and spray a synthetic pyrethroid pesticide in some of the most egregious gap areas of Cobleigh. After that he suggests that we will simply have to wait for cold weather to freeze the soil.

  7. The custodial staff is very short-handed, but Mr. Ford will ask to have the light fixtures in Cobleigh cleaned out once the weather is cold enough to suppress the entry of new flies for the season.