Man-made light is making a real mess of things, ecologically speaking. Years ago, I volunteered on a research team monitoring hawksbill sea turtles on Barbados. The worst task of my expedition was counting the number of hatchlings that had been squashed in the road as they followed the beacon of a bright porch light to their doom.
Hydrochara caraboides, a species of diving beetle that is attracted to lay its egg on cars, especially red ones.
Photo: Gyorgy Kriska
What I didn't realize is that light pollution is messing with the little critters, too. Insects that breed and feed on the surface of the water are living in a warped world. Anything shiny and dark looks like water to a bug, so insects are laying eggs on everything from asphalt to solar cells.
Since insects rank near the bottom of the food chain, their disoriented way of living could trickle up and affect their predators, too. When a population of dragonflies, for example, drops all its eggs on the highway rather than the pond, anything that feeds on them will be hurting for a meal.
Bruce Robertson, an ecologist studying at the W.K. Kellogg Biological Station in Michigan, is studying the effects of light reflected from man-made structures. Robertson notes there also might be potential for turning this finding to an advantage. In locations where trees are being destroyed by insect infestations, for example, "you may be able to create massive polarized light traps to crash bark beetle populations," if such species are found to be responsive to polarized light cues.