Thursday, July 28, 2011

Deer Fly eggs


If you have been reading my blog this spring and summer you will have noticed that I have been looking for tracks and signs of insects and my afternoon at Sleepy Creek WMA was no exception. While I was down by the lake in one of the coves I was looking for dragonfly exuvia and was rewarded with these deer fly eggs.


They are in the family Tabanidae, genus Chrysops but other than that I don’t know the species of these. I did happen to see a fly laying eggs but by the time I moved closer and focused my camera it had flown, leaving this very white mass of freshly laid eggs. They lay the eggs in tiers which contain a few to several hundred eggs. The eggs are cylinders measuring from 1 to 2.5 mm long. Their choice location is on vegetation which hangs over water so I was in a prime spot along this lake where the vegetation is not too dense. The eggs first appear white as in this photo and later turn brown as in the first photo and then almost black as in the last photo. I thought myself lucky to have found all three stages in the same area.


After about 4-5 days the eggs hatch and the larvae drop down and burrow into the soil. They will overwinter and mature in late spring.

Like mosquitoes the female requires a blood meal before laying her eggs. The bite can be very painful so if you see a large fly ¼ to ½ inch long with yellowish markings, clear wings with black or brown pattern that look like bands, shoo her away before she bites you. The males are probably feeding on nectar or protecting territory and could care less about the blood running through you veins.

In the past when I walked through the woods I would see stuff like this and keep going. Now I have learned to stop and really look at new, odd and strange things and I have found them quite intersting.  It gives me more of a connection and appreciation for the lives of other creatures on our planet.

2 comments:

Jacqueline Donnelly said...

Everywhere we look, something amazing! I confess, though, that I hate deerflies so much I would be tempted to destroy their eggs. But then I remember that all God's chilluns got a right to live. But I still smack them or wear those deerfly patches on my hat.

squirrel said...

I read that deer flies can transmit Lyme Disease so I am inclined to agree with you.