Shaking things up: the unique feeding behaviour of western banded geckos when consuming scorpions

Abstract

AbstractPredators that feed on dangerous prey species must evolve mechanisms to reduce the likelihood of injury or death during a predation attempt. Scorpions are prime examples of dangerous prey items for insectivores, because they can inflict a venomous and potentially fatal sting when attacked. Despite this risk, the western banded gecko (Coleonyx variegatus), a generalist insectivore, occasionally preys on dune scorpions (Smeringurus mesaensis). We use high-speed videography to examine the modulation of prey capture biomechanics in relationship to prey type. The capture of undefended evasive (cricket) and non-evasive (worms) prey follows previous studies of lizard attack kinematics. However, we have discovered a unique shake-feeding behaviour used by western banded geckos when feeding on scorpions, whereby the gecko bites the scorpion, then performs very rapid side-to-side shaking with its head and body. Given the speed and violence of shake-feeding, we suggest that geckos shake the scorpion to cause mass trauma and subsequent immobility or, potentially, to break the stinger and render the scorpion harmless. This behaviour might be widespread among geckos that feed on these dangerous prey species.