FEEDING-HABITS AND PREDATORY BEHAVIOR IN THE MARBLED POLECAT (VORMELA-PEREGUSNA-SYRIACA) .1. KILLING METHODS IN RELATION TO PREY SIZE AND PREY BEHAVIOR

The marbled polecat (Vormela peregusna syriaca), a small musteline, is represented in the fauna of Israel. Predatory behaviour of eleven marbled polecats, caught in the field, and held in captivity for a reproductive biology study, was observed during their routine feedings over the course of two years. Sequences of prey capture and killing were recorded on film or videotape. Killed prey were also retrieved for autopsy. Prey offered included Gallus gallus domesticus, Mus musculus, Acomys cahirinus, Microtus guentheri, Meriones tristrami, Cavia porcellus and Rattus norvegicus. All prey items were obtained as surplus from medical laboratories. In addition to using the typical musteline killing method of biting the nape of the neck, marbled polecats used a variety of killing methods suited to a range of prey types. Two variables determined the killing method used. 1) Size of prey: Small prey were killed by bites to the thorax, whereas large prey were bitten on the head or neck. 2) Prey defense behaviour: Fleeing prey were bitten dorsally, whereas defending prey were bitten ventrally, typically on the throat. This non-stereotypical predatory behaviour appears to correlate with the opportunistic feeding habits of marbled polecats in the wild. Evolutionary and ecological aspects of this relationship are discussed.