Animals caught in ‘ecological traps’ prefer the worst available habitats. This happens when environmental change makes habitats look superficially attractive when they are actually dangerous. Ecological traps are increasingly common, but it remains unclear how susceptible animals are to them. Aquatic flies, for example, can be highly attracted to asphalt because it reflects polarized light the same way that natural water bodies do.
In this study, Bard professor Bruce Robertson and his students exposed seven ecologically similar species of aquatic flies to different levels of polarized light, including abnormally strong polarized light associated with man-made habitats that are dangerous to them. They found that, in every species tested, animals actually preferred levels of polarized light typical of asphalt where their eggs perish, over levels typical of natural ponds. We also found that the degree of their preference depended on whether the cue was closer or more distant from a natural river.
Citation: Robertson, B. A., Keddy-Hector, I. A., Shrestha, S. D., Silverberg, L. Y., Woolner, C. E., Hetterich, I., & Horváth, G. (2018). Susceptibility to ecological traps is similar among closely related taxa but sensitive to spatial isolation. Animal Behaviour, 135, 77-84.