Polyboroides radiatus Predation Attempts on Propithecus verreauxi

Abstract

Observations of raptor predation on lemurs are rare [reviewed in Goodman et al., 1993], but indirect evidence derived from raptor prey remains [Karpanty and Goodman, 1999; Thorstrom and La Marca, 2000], raptor pellets [Goodman et al., 1993], and vocal/behavioral responses to potential avian and terrestrial predators [Sauther, 1989; Karpanty and Grella, 2001; Schulke, 2001; Fichtel and Kappeler, 2002] suggest that predation may play an important role in regulating lemur populations. Recent reports of Madagascar harrier hawk (Polyboroides radiatus) predation attempts on Cheirogaleus [Gilbert and Tingay, 2001] and Lepilemur [Thorstrom and La Marca, 2000; Schulke and Ostner, 2001] lend support to Goodman et al.’s [1993] contention that increased predation on nocturnal prosimians has evolutionary significance for some taxa (e.g. Microcebus murinus). Polyboroides is a potential predator of large-bodied (3–4 kg) diurnal lemurs as well, based upon the ubiquity of lemur alarm calls, but observations of these predations are few [Propithecus verreauxi: Rasoaninrainy in Goodman et al., 1993]. Based on prey remains, sifaka make up the largest component of the harrier hawk’s courtship diet in terms of biomass [Karpanty and Goodman, 1999] at Berenty and Bealoka Reserves. Here I report three predation attempts of Polyboroides on adult Verreaux’s sifaka, P. verreauxi, at Beza Mahafaly Special Reserve (BMSR), Madagascar.