Melanistic leopards reveal their spots: Infrared camera traps provide a population density estimate of leopards in malaysia

Abstract

To date, leopards (Panthera pardus) in Peninsular Malaysia have been overlooked by large carnivore researchers. This is in part due to the country's unique population of individuals that are almost all melanistic, which makes it nearly impossible to identify individuals using camera traps for estimating leopard density. We discovered a novel modification to infrared flash camera traps, which forces the camera into night mode, that allows us to consistently and clearly see the spots of a melanistic leopard. The aim of this project was 1) to determine the feasibility of identifying melanistic leopards with confidence using infrared flash camera traps, and 2) to establish a density estimate for the leopard population in a wildlife corridor in Malaysia using maximum likelihood and Bayesian spatially explicit capture‐recapture (SECR) models. Both SECR approaches yielded a leopard density of approximately 3 individuals/100 km2. Our estimates represent the first density estimate of leopards in Malaysia and arguably, the world's first successful attempt to estimate the population size of a species with melanistic phenotypes. Because we have demonstrated that melanistic leopards can be monitored with confidence using infrared cameras, future studies should employ our approach instead of relying on scars or body shape for identification. Ultimately, our approach can facilitate more accurate assessments of leopard population trends, particularly in regions where melanistic phenotypes largely occur. © 2015 The Wildlife Society.

Ecology and Evolution of Melanism in Big Cats: Case Study with Black Leopards and Jaguars

“…Our data support the findings reported by [14] and [15], showing that melanism is almost fixed in areas south of the Isthmus of Kra (Thailand/Malaysia). This study obtained only two records of nonmelanistic animals south of the Isthmus, while in more northerly areas both phenotypes appear at similar frequencies.…”

“…The occurrence of melanism is rather common in Felidae, having been documented in 13 of the 38 felid species, evolved independently at least eight times within the family [11][12][13], in some cases reaching very high frequencies in natural populations [14,15]. In none of them has it reached fixation, but rather always exists as a polymorphic phenotype, and it is present only in two species of Panthera: the leopard (P. pardus) and the jaguar (P. onca) in contrast of the spotted wild phenotype present in these species.…”

“…In other hand, melanism in jaguars is inherited as a dominant trait, caused by a 15-base-pair deletion in the MC1R gene that leads to a "gain of function" mutation favoring the production of dark melanin (eumelanin) in the background regions of the coat [11,22]. Although the trait has been well known in these species for many years and easily identifiable in nature (e.g., [15,17,[23][24][25][26]), its geographic distributions, as well as the environmental factors that may influence its persistence in natural populations, are being discovered recently [26][27][28][29].…”

The Discovery of Two Spotted Leopards (Panthera Pardus) in Peninsular Malaysia

“…This is despite the extensive camera trapping efforts in Peninsular Malaysia, all of which (with the exception of the above two studies) have recorded the presence of only the melanistic form [6,[10][11][12][13][14][15]. A study in 2010 examined the frequency of leopard melanism in 22 locations in Peninsular Malaysia and southern Thailand [5] (Fig.…”

Field calibration of blowfly-derived DNA against traditional methods for assessing mammal diversity in tropical forests

“…Frequently used methods include live trapping, such as cage traps (Hanif-Ridzuan et al 2010;Madinah et al 2011), mist nets, and harp traps (Kingston et al 2003;Sing et al 2013), camera traps (Clements 2013;Hedges et al 2015a), indirect signs such as tracks or scat (Daim 2002), interviews with local communities (Sharma et al 2005), direct observations by researchers (Syakirah et al 2000;Jayaraj et al 2013), and hair traps (Castro-Arellano et al 2008;Hedges et al 2015b). Recent additions to the toolbox are secondary sources of mammal DNA, for example, mammal DNA detected from owl-pellet bones (Rocha et al 2015) and invertebrate gut contents (Calvignac-Spencer et al 2013a, 2013bSchnell et al 2012Schnell et al , 2015Lee et al 2015).…”