Blowfly Mystery Update

In a recent post I wrote about a strange case of apparent Blowfly infestations in ADULT purple martins. You can read about it HERE.

The latest issue of “Feathers and Friends” had an interesting interview with Willie Conley, a well known and prominentĀ  purple martin landlord in Indiana. Some excerpts of the article follow:

“Willie… hosts around 250 pairs annually. This year he had 251 pair. …He first had this problem with this parasitic infestation back in 2004 already, but this year was exceptionally bad. This year Willie treated around 70 martins in his own colony that were infested, and they all survived. Though he did find 2 untreated martins that had died of the sickness.

An infested martin starts growing a big pink bubble right at its under tail coverts. In this bubble there are tiny little holes in which there are up to four white little white maggots per hole. Usually just two. Willie has found as many as 23 maggots in ONE martin. These maggots grow bigger and bigger until the martin dies.

Willie saved a dead martin that died of this parasitic infestation to see what the maggots would do. He put the (dead) martin in a sealed jar. The maggots turned into white pupal cases (cocoons) , which later turned to a dark brownish color.”

courtesy of Feathers and Friends


After a couple of weeks this is what had emerged.

(The house fly on the left is for size reference)

According to Dr.Terry L. Whitworth, Owner and Operator, Whitworth Pest Solutions, Inc., and Washington State University Adjunct Professor in Entomology; these photos are Sarcophagidae -flesh flies. They normally only feed on dead nestlings, though occasionally they can infest living tissue, usually via a wound or injury.

Dr.Whitworth brings up an important point though. That since these maggots were from a bird that was found dead that these flesh flies could have deposited the larvae on the dead bird and not necessarily have been the cause of death. Really the only way to be sure is to examine the larvae that are directly removed from the living bird.

So we are left with more questions and still have a mystery. If you have any information that may help us is solving the riddle, please let us know. You can contact us at susan(at)purplemartins-r-us(dot)com or use the contact us page to the right.

The American Bird Conservation Association / Feathers and Friends can be contacted via phone at (260) 768-8095 x:5 Subscription rates areĀ  $18 for 1 year. Tell them Susan from PurpleMartins-R-Us sent you!

Tags: ,

Leave a Reply

You must be logged in to post a comment.