Timing during predator-prey encounters, duration and directedness of a putative pursuit-deterrent signal by the zebra-tailed lizard, Callisaurus draconoides

Some prey attempt to deter pursuit by signaling to a predator that they have detected it and can escape if attacked. Zebra-tailed lizards (Callisaurus draconoides) wag their boldy patterned tails when approached. Wagging is related to predation risk, as predicted for pursuit deterrence, and likely alternative functions have been eliminated. To examine the role of tail-waving in pursuit-deterrence, I studied stages of predator prey encounters when it occurred, its duration and its directedness. Tail-waving occurred before, during and after escape runs, and in all combinations of these times. Display performed before fleeing putatively deters pursuit; during and after fleeing it also might deflect attacks to the autotomizable tail. Tail-waving was brief before and during escape, but lasted up to 13 s after runs ended. Undetected ambushers at new locations attack rapidly and displaying may attract additional predators. Therefore, prolonged display for deflection is unlikely. Lizards display briefly, flee to reduce risk and possibly demonstrate escape ability, then engage in more prolonged signaling. As predicted for a directed signal, tail-waving frequency was higher for lizards oriented at angles that exposed the ventral tail to view than at hid it from view. Tail-waving appears to be a pursuit-deterrent signal directed to predators.