A couple evenings ago I observed a dragonfly exhibiting ovipositing behavior in the back of my Grandpa's pick-up truck. It would fly and hover inches from the black surface of the truck's bed, and then dab it's abdomen on the surface. It did this dabbing motion countless times, and I was able to observe an almost methodical and angular flight to it's behavior. It would turn perfect 45 degree angles most times it went to dab its abdomen.
I'm not sure what kind of dragonfly it was, though it was a dark orangey-brown color, maybe a female tramea transmarina euryale?
After doing a trusty Google search and finding a couple scholarly articles, and a good explanation on Wikipedia, my best guess is that the black, plastic sheeting of the pick-up truck bed mimics the polarity of light reflecting off of a body of water. Perhaps this is because of the undulating nature of the sheeting. The back of my grandpa's pick up truck would therefore be considered an ecological trap. Many other man made items are considered ecological traps for dragonflies and other insects who are attracted to polarized sources of light because they will spend their time guarding a car window rather than a rain puddle, and miss out on food, mates, and ovipositing sites ("Ecological Trap" Wikipedia).
Here is an interesting article about how black gravestones trick dragonflies: Dragonfly pdf
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