ORIGINAL ARTICLE The first description of population density and habitat use of the mainland clouded leopard Neofelis nebulosa within a logged-primary forest in South East Asia Shariff Wan Mohamad 1 • D. Mark Rayan 1 • Wong Chai Thiam Christopher 1 • Muhamad Hamirul 1 • Azlan Mohamed 1 • Ching Fong Lau 1 • Elangkumaran Sagtia Siwan 1 Received: 16 June 2014 / Accepted: 20 May 2015 Ó The Society of Population Ecology and Springer Japan 2015 Abstract The mainland clouded leopard (Neofelis neb- ulosa) is classified as vulnerable under the IUCN Red List, meaning that it faces a high risk of extinction in the wild. However, hardly any ecological research has been pub- lished on this species apart from several radiotelemetry studies in Thailand and Nepal, and one camera-trapping study in India. Here we present findings on the clouded leopard from a camera-trapping study conducted in Te- mengor forest reserve (a logged-over forest) and Royal Belum State Park (a primary forest) within Peninsular Malaysia. Using the spatially-explicit capture-recapture method, the density from Temengor forest reserve and Royal Belum State Park was estimated at 3.46 ± SE 1.00 and 1.83 ± SE 0.61, respectively. Clouded leopard habitat use was found to be highly influenced by the availability of small and medium prey species and therefore intrinsically highlights the potential conservation importance of species such as pig-tailed macaques, porcupine, mouse deer and small carnivores. These findings provide the first estimates of density and habitat use of this species in a logged-pri- mary forest from both Peninsular Malaysia and South East Asia. Our study provides important baseline information on clouded leopards and contributes to filling up the knowl- edge gap that exists in understanding the population ecol- ogy of this species, not only within Peninsular Malaysia, but also on a regional level. Keywords Belum–Temengor Á Camera-trap Á Density Á Habitat use Á Peninsular Malaysia Á Spatially explicit capture-recapture Introduction The clouded leopard (Neofelis spp.) is a medium-sized felid (approximately 11–23 kg), reaching up to about one metre in head-body length (Hearn et al. 2013). It is a charismatic species, in which its name is derived from the cloud-like patterns on its pelage. The clouded leopard is classified as Vulnerable under the IUCN Red List (Sanderson et al. 2008), meaning that it faces a high risk of extinction in the wild. The main threats to this species are deforestation and hunting for the illegal wildlife trade (Sanderson et al. 2008). The clouded leopard ranges from central Nepal and southern China all the way south to Peninsular Malaysia, in addition to the islands of Sumatra and Borneo (Austin et al. 2007). It was recently classified as two separate species, whereby the population in Sumatra and Borneo was recognised as the Sunda clouded leopard (Neofelis diardi) based on DNA and morphological analysis, separating it from the mainland clouded leopard (Neofelis nebulosa) (Buckley-Beason et al. 2006; Kitchener et al. 2006; Wilting et al. 2007, 2011). Although clouded leopards are adapted for climbing, it is likely that they move primarily on the ground (Rabi- nowitz et al. 1987; Grassman et al. 2005) and use trees only for resting or occasional hunting (Nowell and Jackson 1996). The clouded leopard has unique morphological features such as having the longest canines proportionate to its body compared to all other living felid species (Gug- gisberg 1975); however, little is known about its prey preference. Current knowledge of its diet is mostly based & D. Mark Rayan mdarmaraj@wwf.org.my 1 WWF-Malaysia, 1 Jalan PJS 5/28A, Petaling Jaya Commercial Centre (PJCC), 46150 Petaling Jaya, Selangor, Malaysia 123 Popul Ecol DOI 10.1007/s10144-015-0494-1