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.
•Activity budget and home range of individuals and troops of Toque Macaques differ in areas of different levels of anthropogenic pressure.•Toque Macaques in human-dominated landscapes allocate more ...of their activity budget for resting, locomotion, vigilance, and communication.•Toque Macaques inhabiting human-dominated landscapes use a smaller home range than those inhabiting forested landscapes.•A growing negative public opinion toward the Toque Macaques suggests the intensifying human-macaque conflict.
While classified as endemic and endangered, the Toque Macaque (Macaca sinica) is also considered a nuisance species in certain habitats in Sri Lanka due to its increased interactions with humans and crop raiding. This study analyzed the activity budget and home range utilization of two M. sinica troops inhabiting two contrasting landscapes to shed light on the species' rather poorly understood behavioral responses under environments of differing levels of anthropogenic pressure. We observed two macaque troops; first in a landscape with lower anthropogenic pressure (LAP) in Yagirala, and second in an area of moderate anthropogenic pressure (MAP) in Korathota, Sri Lanka. We followed the troops for ten months and observed their behaviors using focal animal sampling. Both troops spent most of their time on foraging and locomotion. However, the Korathota (MAP) troop spent more time on vigilance behaviors than the Yagirala (LAP) troop, which spent more time on amicable behaviors. This suggests that time allocation to amicable behaviors by Toque Macaques is higher in areas with lower anthropogenic pressure. The home range size was significantly larger in Yagirala (LAP) troop. We further found a significant difference in average home range size across seasons in both troops (p=0.001) with larger home ranges in the dry season: 2.81ha in the wet season vs 3.98 ha in the dry season for MAP troop and 5.1ha in the wet season vs 8.66ha in the dry season for LAP troop. Findings suggest that the resource availability and the level of anthropogenic pressure influence the activity budget and home range size of Toque Macaques. The outcomes of this study may be instrumental in developing future management strategies for Toques Macaques in anthropogenic settings and reducing human-macaque conflict. Practical management and conservation efforts should reduce the availability of anthropogenic food sources to macaques while increasing the size of natural forest patches.
The Indian pangolin (Manis crassicaudata) has a wide distribution in the Indian subcontinent and is a threatened species throughout its range due to hunting, poaching, trafficking, and destruction of ...natural habitats. Many rescue programmes for Indian pangolins have had limited success due to the paucity of literature on the diet, ecology and its behaviour. This study investigated the dietary composition and foraging habitat preference of the Indian pangolin in a tropical lowland forest-associated landscape of Southwest Sri Lanka. Five types of habitat were considered in this study: forest, rubber plantation, cinnamon cultivation, oil palm plantation, and tea-dominated home gardens/cultivated areas. The foraging intensity of Indian pangolin in the five habitat types was assessed using signs of foraging activities observed in five 10 × 10 m plots placed along a transect. Ten transects were established in each habitat assessed. The forest habitat was preferred in the studied landscape, followed by rubber plantations, the cinnamon cultivations, oil palm plantations and the tea-dominated home gardens/cultivated areas. Indian pangolins mostly predated on termites, as indicated by the number of feeding events on termitaria and termite-infested logs. Faecal content analysis further revealed that the undigested matter (by weight) was predominantly composed of grit (53.3%), insect matter (37%) and plant matter (9.7%). The digestibility of termite heads, mouthparts, abdomens, and legs was high compared to that of ants. This difference in digestibility was evident from the presence of significantly more heads, mouthparts, abdomens, and legs of ants in the faecal matter, compared to that of termites. However, undigested termite wings were frequently observed in the faecal matter. Termites of the genus Odontotermes and ants of the genera Oecophylla, Anoplolepis, Camponotus and Monomorium were the main prey species of the Indian pangolin in the studied area. The findings on the dietary composition have implications in captive rearing and husbandry of Indian pangolins. In addition to natural forests, the findings of the study suggest that human-modified agricultural lands adjoining forest also serve as important as foraging habitats for Indian pangolins, and such habitats should be considered in long-term conservation planning.
An accurate morphological description and analysis based on reliable data are unavailable for the geographically isolated population of
in Sri Lanka. This study provides the most updated ...morphological description of
with special reference to body measurements directly obtained from 27 specimens collected island-wide. Morphological parameters were recorded under three age classes that were defined based on their body weight (BW) and total body length (TBL); juvenile (BW: <4.3 kg TBL: <56.0 cm), subadult (BW: 4.3-7.3 kg TBL: 56-101 cm), and adult (BW: >7.3 kg TBL: >101 cm) and gender to reveal sexual dimorphism based on morphometric parameters. The TBL of adult males ranged between 137 and 177 cm while body weight ranged between 20.4 and 48.8 kg. The average count of body scales was 511 ± 21. The body scales were found arranged in 13 longitudinal rows with the highest number of scales observed on the vertebral scale row (16 ± 1). Three major scale morphs were identified; broad rhombic scales, elongated kite-shaped scales, and folded shaped scales. Broad rhombic shaped scales was the dominant scale type (80.49%) on the body (405 ± 7). The tail-length to body-length ratio of an Indian pangolin was 0.87. The tail length of an Indian pangolin is a reliable predictor of the TBL and has potential implications in quick field data gathering.
Background We investigated the impact of human recreational disturbances on the distribution of birds along a popular nature trail in Sinhararja World Heritage Forest, Sri Lanka. It was hypothesized ...that visual and noise stimuli caused by the presence of humans affect the distribution of avifauna associated with this nature trail. Methods Nine circular plots of 25 m fixed-radius laid along the trail (0 m), and 18 plots laid perpendicular to the trail at 75 and 150 m intervals, were studied from March 2013 to January 2014. The degree of human recreational disturbances was assessed in terms of visitor group size (visual disturbance) and their noise level (sound disturbance). These disturbances were categorized along a four-point scale (no human disturbance, low, medium and high disturbance). The relationship between disturbance levels and the abundance of birds was statistically tested. Results ANOVA results revealed that the abundance of birds differed significantly under various intensities of recreational disturbances at each distance level. A significant negative correlation between abundance of birds and intensity of disturbance at 0 m distance suggests an avoidance of edge habitats by birds in the presence of humans. Abundance of birds increased at the 75 and 150 m distance levels with increasing disturbances occurring at the trail. Significant negative correlations were further observed between disturbance level and the abundance of birds in ground/understory and sub-canopy vertical strata of the forest at 0 m distance. Conclusions Under high levels of recreational disturbance occurring at this trail, the abundance of birds near the trail declined significantly, while bird abundance in the interior of the forest increased. The sensitivity of individual bird species to visitor disturbances varied with the vertical stratum of the forest they usually occupy. Birds occupying the ground, understory and sub-canopy are particularly sensitive to recreational disturbances while bird species occupying the canopy and above are less vulnerable to recreational disturbances.
Asian Elephants feed predominantly on grass. The comparative nutritional contribution of grasses and other elephant forage is not known. Therefore, the proximate nutrition of food plants selected by ...elephants, and the relationship of their diet composition to body condition and gender were examined in this study. Proximate analysis was conducted on 11 plant species recognised upon 66h of opportunistic focal animal sampling. Five species among them were grasses, including the invasive Megathyrsus maximus. The micro-histological composition of freshly collected dung from 26 identified elephants was assessed against their body condition and gender. Associations, comparisons, and hypotheses were tested. Dicots were significantly high in dry matter and low in moisture, while monocots were high in moisture and low in dry matter (p <0.001). The average monocot: dicot ratio was 1: 0.73 in elephant diet. However, it was observed that the monocot composition in the male diet was significantly higher than dicots (p <0.001), while there was no significant difference in the female diet composition. Elephant body condition did not show any correlation with the abundance of monocot or dicot plant tissues. The preliminary study implies that dry matter nutrients in dicots and moisture in monocots influence diet selection of elephants. Their diet composition was associated with gender but did not correlate with body condition. M. maximus was not outstanding in nutrition from the selected plant species.
We studied garbage consumption by Asian elephants at the Uddakandara garbage dump in southern Sri Lanka. Garbage at the dump was classified under six categories and quantified using a grid overlay. ...Elephants visiting the dump were individually identified by morphological criteria and items and quantities consumed by them were determined by focal animal sampling. Dung of elephants that did not consume garbage and those from the dump were compared quantitatively and dung constituents assessed by washing through three layered sieves. A total of 17 individual elephants visited the garbage dump during the study period, all of who were males. The observed sexual bias could be related to behavioural differences between the sexes. Elephants mostly consumed ‘fruits and vegetables’ and ‘prepared food’, possibly due to their higher palatability and nutritional value. Ingestion of polythene was incidental and associated with consuming prepared food. Proportions of the six categories in elephant diet and garbage piles were significantly different, indicating that elephants were highly selective when feeding. Elephant arrivals increased in response to unloading of garbage, suggesting attraction to fresh garbage. Dung analysis found that garbage consumption did not change the quantity and constituents of dung, except for the presence of anthropogenic items. As consumed anthropogenic items were regularly excreted, retention and obstruction of the alimentary tract are unlikely in elephants. Elephants feeding on garbage had better body condition than non-garbage consuming elephants, indicating that garbage provided better nutrition than natural food and was not detrimental to their health.
A general decrease in populations of waders on the Ythan estuary, Aberdeenshire, has coincided with an increased biomass of green algae on the intertidal mudflats. It was hypothesised that the ...reduction of bird numbers was due to the impact of macroalgal mats. The main objective of this study was to test the above hypothesis by investigating the impact of macroalgal mats on aspects of the behavioural ecology of waders, principally on their dispersion, diet and foraging behaviour. Redshank (Tringa totanus L.), curlew (Numenius arquata L.), oystercatcher (Haematopus ostralegus L.), bar-tailed godwit (Limosa lapponica L.) and dunlin (Calidris alpina L.; for study of dispersion only) were chosen for study. To test this hypothesis, wader counts on different estuary sections, pellet and dropping analysis, direct observations on foraging, visual and photographic estimations of weed cover, and invertebrate data were assessed in the context of the energetics of waders and their prey described in the literature. Foraging behaviour was examined on weed-covered and weed-free sediments in natural sites and in field-manipulated plots. Weed cover below 25% (biomass <1 kg fresh weight/ m2) did not adversely influence the foraging of redshank, curlew, oystercatcher and bar-tailed godwit. However, weed cover >50% (biomass > 3 kg fresh weight/ m2) negatively affected the foraging of redshank, curlew and bar-tailed godwit but did not consistently affect oystercatcher. Redshank that fed on weed-covered areas had a reduced numerical food intake rate when compared to the birds on weed-free areas. During peak weed cover on the estuary, redshank on weeded areas had a 35.8% lower gross energy intake rate than those on weed-free areas.
A general decrease in populations of waders on the Ythan estuary, Aberdeenshire, has coincided with an increased biomass of green algae on the intertidal mudflats. It was hypothesised that the ...reduction of bird numbers was due to the impact of macroalgal mats. The main objective of this study was to test the above hypothesis by investigating the impact of macroalgal mats on aspects of the behavioural ecology of waders, principally on their dispersion, diet and foraging behaviour. Redshank (Tringa totanus L.), curlew ( Numenius arquata L.), oystercatcher (Haematopus ostralegus L.), bar-tailed godwit (Limosa lapponica L.) and dunlin (Calidris alpina L.; for study of dispersion only) were chosen for study. To test this hypothesis, wader counts on different estuary sections, pellet and dropping analysis, direct observations on foraging, visual and photographic estimations of weed cover, and invertebrate data were assessed in the context of the energetics of waders and their prey described in the literature. Foraging behaviour was examined on weed-covered and weed-free sediments in natural sites and in field-manipulated plots. Weed cover below 25% (biomass <1 kg fresh weight/ m2 ) did not adversely influence the foraging of redshank, curlew, oystercatcher and bar-tailed godwit. However, weed cover >50% (biomass > 3 kg fresh weight/ m2) negatively affected the foraging of redshank, curlew and bar-tailed godwit but did not consistently affect oystercatcher. Redshank that fed on weed-covered areas had a reduced numerical food intake rate when compared to the birds on weed-free areas. During peak weed cover on the estuary, redshank on weeded areas had a 35.8% lower gross energy intake rate than those on weed-free areas.
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