Surface foraging in Scapanus moles

Abstract

Abstract Some mole genera, including Scapanus of western North America, are usually considered to be fully fossorial. I present data showing that surface foraging is used by adults of all four Scapanus species, and evidence that such foraging is not a particularly rare behavior. Scapanus moles forage on the surface when leaf litter is wet and does not produce much noise; they also move slowly, remain within a small area, and usually forage in places with dense cover. These adaptations decrease the risk of predation and make surface foraging behavior difficult to detect for human observers. Numerous unpublished and a few published observations suggest that many, if not all, species in other “fully fossorial” mole genera forage on the surface at least occasionally. This is true not just for true moles (Talpidae), but also for unrelated, but convergently similar golden (Chrysotalpidae) and marsupial (Notoryctidae) moles. Apparently, surface foraging is too important for fossorial insectivores to be completely lost even in the most fossorial taxa.