SHORT COMMUNICATION Pilot survey of avahi population (woolly lemurs) in littoral forest fragments of southeast Madagascar Ivan Norscia Received: 22 June 2007 / Accepted: 30 July 2007 / Published online: 6 September 2007 Ó Japan Monkey Centre and Springer 2007 Abstract This study presents a pilot survey of the avahis (pair-living, nocturnal prosimians) living in threatened lit- toral forest fragments of southeastern Madagascar. In the period of October–December 2004, I evaluated the density of adult and newborn avahis (carried by the mothers) by counting the individuals encountered during 58 night walks in seven fragments of Sainte Luce and Mandena forests, along one trail/fragment. Along each trail, I used random plots (5 m 2 ) for a preliminary characterization of the veg- etation. The density of the population was not correlated with fragment size and number of plant morphospecies, while it was correlated with large tree availability. Possibly due to a low energy diet based on leaves and to specialized and energetically expensive vertical leaping, the loss of large trees by selective logging seems to affect avahi populations more than other variables. Keywords Avahi laniger Á Avahi meridionalis Á Degradation Á Fragmentation Á Littoral forest Á Madagascar Introduction Habitat fragmentation, which threatens the survival of lemurs in Malagasy forests (Mittermeier et al. 2006), is only one step of the degradation process, also including habitat loss, edge effects, land use in the surrounding areas, hunting, and har- vesting (Tabarelli and Gascon 2005). Population estimates are unavailable for many lemur species, and effective conservation plans cannot be implemented if the effects of habitat reduction on lemurs are not clarified (Mittermeier et al. 2006). Relatively few studies have focused on single species in non-protected fragments of Malagasy littoral forest (cf. Lawes et al. 2000; Ganzhorn et al. 2003). This study focuses on the populations of nocturnal woolly lemurs (avahi or fotsyfe, Indriid family) of littoral forest fragments of southeastern Madagascar (forest of Mandena and Sainte Luce), recently recognized as Avahi meridionalis (instead of A. laniger; Zaramody et al. 2006). Such popu- lations are worth studying for different reasons. First, they are confined to littoral forests (Bollen and Donati 2006), one of the most threatened ecosystems of Madagascar (with less than 3,000 ha remaining). Secondly, avahis are vertical leapers, and vegetation destruction can create a barrier to migrations from one local population to another, reducing the possibilities that animals persist in metapopulations (Lawes et al. 2000; Thalmann 2003). Third, the species living in monogamous pairs like avahis (Thalmann 2003) may be more prone to ‘‘demographic’’ extinction than the species living in extended groups with promiscuous mating (Dobson and Lyles 1989). Lastly, the removal of trees can lower leaf production and affect the survival of small-bodied folivores like avahis (Thalmann 2003). In Mandena and Sainte Luce, forest clearance is exercised for plantations, charcoal, cooking, and buildings (Vincelette et al. 2003). This pilot study presents the first survey of avahis cov- ering seven littoral forest fragments of southeastern Madagascar. Materials and methods I collected data in the seven forest fragments (southeast Madagascar; Fig. 1) where avahis were reported to live I. Norscia (&) Museo di Storia Naturale e del Territorio, Centro Interdipartimentale, Universita ` di Pisa, Via Roma 79, 56011 Calci, Pisa, Italy e-mail: norscia@lunet.it 123 Primates (2008) 49:85–88 DOI 10.1007/s10329-007-0061-2