Habitat preference and den characterization of Indian Pangolin (Manis crassicaudata) in a tropical lowland forested landscape of southwest Sri Lanka

Abstract

The Indian pangolin (Manis crassicaudata) is under threat due to hunting for local consumption and illegal trafficking of scales and meat. The dearth of scientific studies on the ecology of the M. crassicaudata has impaired accurate assessments of its conservation needs. This study investigated the habitat preference and burrow characteristics of M. crassicaudata in a tropical lowland rainforest in southwest Sri Lanka. A total of 75 burrows (54 feeding burrows and 21 resting burrows) of M. crassicaudata in four different habitat types i.e. secondary forest, Pine-dominated forest, rubber cultivations and tea-dominated home gardens bordering forest were observed using fixed-width transects in order to characterize resting and feeding burrows of this species. The highest density of resting burrows was recorded from the secondary forest (4ha-1), followed by rubber cultivations (2.5ha-1) while no resting burrows were recorded in the Pine-dominated forest and the tea-dominated home gardens bordering forest. Feeding burrows were more abundant in the Pine-dominated forest (5.7ha-1). The burrow depth, burrow opening height, and width were significantly larger in resting burrows compared to feeding burrows. Resting burrows were located at higher elevations (75-100m) with moderately high slopes (450−600), dense canopy cover (>75%) and away from human habitation. Feeding burrows showed a greater variability in terms of associated environmental features. The study further revealed that Indian pangolins exclusively prefer habitats with rocks and boulders under which they dig resting burrows while the location of feeding burrows largely overlaps with the distribution of prey species. The resting burrow design consisted of a bending tunnel that initially slopes downward and then gradually inclines at an angle between 20 and 300, leading to the resting chamber. Our study highlights the importance of conserving fragmented secondary natural forests in changing landscapes of the southwest lowlands of Sri Lanka as these habitats appear to be critical to sustaining populations of M. crassicaudata.

The Ants (Hymenoptera, Formicidae) of Sri Lanka: a taxonomic research summary and updated checklist

“…However, the current legal framework for biodiversity conservation allowing the export of specimens outside Sri Lanka is very restrictive and might represent a serious limitation to the completion of the taxonomic work that could be undertaken within the country. Moreover, with ongoing landscape modification in the region, many species have been driven to critical status ( Somaweera et al 2015 ; Perera et al 2017 ; Karawita et al 2018 ), therefore, urgent, large-scale, and sustained efforts to monitor, characterize, and conserve the ant fauna of Sri Lanka is critical.…”

Updates on the Morphometric Characterization of Indian Pangolin (Manis crassicaudata) in Sri Lanka

“…The behavioral plasticity of the Indian pangolin has enabled it to inhabit an array of natural and human-modified landscapes [ 1 ]. It has been reported that Indian pangolins exhibit different behavioral adaptations in lowland wet zone habitats and dry zone habitats in Sri Lanka [ 7 ]. The specific habitat an individual occupies can further affect the wearing of the claws and scales [ 7 , 8 , 22 ].…”

“…Hunting, poaching, and trafficking, primarily driven by the demand for its keratinous scales and meat, have made the Indian pangolin threatened across its range [ 2 ]. Despite being identified as “endangered” globally and nationally, limited studies have been conducted on Indian pangolins found in Sri Lanka [ 5 , 7 , 8 ], and the lack of scientific information on the species is a major impediment in the conservation of Indian pangolins [ 9 ].…”

Dataset of distribution, habitats and conservation status of the Indian pangolin (Manis crassicaudata) in Sri Lanka

“…Thus indirect methods such as camera trap surveys, sign surveys and community surveys are often used by researchers [[3], [4], [5]]. Field data gathered by the authors during ecological surveys to determine the abundance [6,7], and habitat utilization of Indian pangolins [5] in the South-west lowland forest and associated landscapes in Sri Lanka (Yagirala: 6°21′ to 6°26′ N and 80°08′ to 80°11′ E), and two other study locations (Wilpattu: °13′ to 8°40′N and 79°50′ to 80°10′E and Yala: 6°18′ to 6°42′N and 81°24–81°43′E) from August 2013 to December 2018 were used as primary data on pangolin recordings. We collected data on the distribution, rescue and wildlife crimes involving Indian pangolins from January 2000 to December 2018 to update the distribution and conservation status of Manis crassicaudata in Sri Lanka.…”