10 June 2010

nature: Hawkmoths and the Tower

Today I had the privilege of going to the top of the University of Texas Tower building, an icon around these parts for both architectural and historical reasons. For the latter, it's open only by tour and special appointment.

As I was tooling around taking photos of the 360 degree view, I noticed that there were a ton of moth wings littering the observation deck. I assumed that the poor moths were attracted to the lights and banged themselves to death up there.

Then, I noticed that there were at least 6 live moths hanging around the walls up there of my favorite kind: the hawkmoth. These beauties, of the species Manduca quinquemaculatus, are huge. I'd say their wingspan is at least 6 inches. The gray patterns on their wings are gorgeous and they hide away the bright orange striped abdomen.

I was surprised to find them up so high, and also all on the north side of the building. If they flew low to the ground at night, I'd expect to find them gathered around all manor of lights around our buildings. But these were way up there, which either means they are particularly attracted to the VERY bright Tower lights or they fly way high up...or both.

At any rate, I turned around a corner and discovered one of two female grackles grabbing one of my moths off the wall, tearing its wings off and devouring the fat abdomen. A hefty meal for those birds, and an explanation for all of the abandoned wings along the floor. (Grackles, in my opinion, still have quite a bit of the wily T. rex in their genes. Just watch them hunt for a while.)

Anyway, neat. Nature on top of the city.


Elizabeth Barrow said...

I like hawkmoths too -- but the caterpillars are devasting. I wish I could train a grackle to do some selective enforcement around my garden! Thanks for the post and great pictures...

Linda said...

One more way to tell this is a quin and not a sexta, is the two "blue eyes" on the thorax. Sextas don't have this.