Earwigs are a new, surprising addition found in the diet of skinks at Point Pelee National Park, Ontario, Canada.

Five-lined skinks (Plestiodon fasciatus) are scaled reptiles, 12 – 20 cm snout-vent length, found from southern Ontario to northern Florida. Skinks are geographically widespread and opportunistic predators, suggesting that they have the capacity to eat prey as it becomes available in a season or area. Individuals excrete compact, dry 1 – 2 cm cylindrical brown scats with a white uric acid plug, dominated by the exoskeletons of consumed invertebrates, and diet can be partially inferred during scat dissection.

Spider exoskeletons dominated the scats of a skink population in Point Pelee National Park in 2000, and a team re-surveyed the same population and a nearby population in 2013 (Brazeau et al. 2015). The composition of invertebrates changed in 2013: skinks from both populations ate great numbers of non-native European earwigs (Forficula auricularia), an item which was not detected in 2000. In fact, the European earwig, a ground arthropod, was first detected in large numbers in southern Ontario in 2011. To Brazeau and colleagues, this suggests that skinks have an adaptive diet and provide ecosystem services to humans, like controlling the ground-active European earwig!

When’s the last time that you looked closely at a scat, and what did you find?

Citation: Brazeau, D., R. Freitag, S. Hecnar, D. Hecnar. 2015. Comparing Common Five-lined Skink (Plestiodon fasciatus) Diet Among Populations and Time. Herpetological Review 46(3): 331-336.