Subfossil lemur discoveries from the Beanka Protected Area in western Madagascar

A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.

Arboreal camera trapping for the Critically Endangered greater bamboo lemur Prolemur simus

Camera traps are standard tools for assessing populations of medium–large terrestrial mammals, particularly for rare, elusive or cryptic species, yet few researchers have attempted to employ camera traps to document rare primates in arboreal settings. We examined different arboreal camera-trap techniques to document the Critically Endangered greater bamboo lemur Prolemur simus in Madagascar. We documented P. simus at two sites, confirming presence at one site. Most species, including 86% of all lemur occurrences, were documented in low light conditions (c. < 105 lux). Our study suggests that camera traps can be effective in validating unconfirmed sightings of rare or secretive primate species. We recommend that future work with cameras in arboreal settings considers seasonal activity patterns, targets sites with high food densities, uses local knowledge, and utilizes available techniques (e.g. traditional trapping techniques) and landscape topography to concentrate animal movement (e.g. steep slopes or ridge lines).