Tuesday, May 18, 2010


We just received our latest shipment of fly parasites in the mail.

If you've got yard chickens, you've got chicken poop. If you've got chicken poop, you get flies. In the past, we managed this problem with fly traps (which attract flies by smelling worse than chicken poop). Last year we started using biological control. There's a company that breeds parasitic wasps that lay their eggs in fly larvae. The eggs hatch in the fly pupa, and the wasps eat the developing fly from the inside. The fly dies, and wasps hatch out of the pupa.

So, what you get in the mail is an envelope of fly pupae that are just starting to produce zillions of teeny wasps (the guy in the photo is about 2mm; the big brown thing is a fly pupa). You dump these guys out where the chicken poop is, and they attack the flies. They work very well; we haven't had any fly problems at all.

As a microbiologist, I should write something about how the bacteria Wohlbachia manipulates the wasps' reproductive system. Instead, I'll quote Darwin:

I cannot persuade myself that a beneficent and omnipotent God would have designedly created parasitic wasps with the express intention of their feeding within the living bodies of Caterpillars.

And William Blake, who is a little too trippy for me:

Little Fly,
Thy summer's play
My thoughtless hand
Has brushed away.

Am not I
A fly like thee?
Or art not thou
A man like me?

For I dance
And drink, and sing,
Till some blind hand
Shall brush my wing.

If thought is life
And strength and breath
And the want
Of thought is death;

Then am I
A happy fly,
If I live,
Or if I die.


  1. This of course all begs the question, "How's the wasp infestation going?"

  2. Honestly, I've never noticed them--and I've looked. The bigger problem in the garden is the giant carpenter bees that sound like they're powered by a gas engine.