Epuddling in Elephant Dung by Lepidopterans in Wasgamuwa, Sri
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Research Article Gajah 46 (2017) 14-20 Puddling in Elephant Dung by Lepidopterans in Wasgamuwa, Sri Lanka Chandima Fernando1*, Ravi Corea1, Chinthaka Weerasinghe1 and Prithiviraj Fernando2 1Sri Lanka Wildlife Conservation Society, Wasgamuwa, Sri Lanka 2Centre for Conservation and Research, Tissamaharama, Sri Lanka *Corresponding author’s e-mail: [email protected] Abstract. We recorded puddling of lepidopterans on elephant dung in Wasgamuwa. In 148 days of observation, puddling was observed on nine days, on 9 of 978 dung piles examined, suggesting that the behaviour was uncommon. We identifed 26 butterfy species from six families who engaged in this behaviour, indicating that elephant dung puddling was much more wide spread among butterfy species than recognized previously. All puddling occurred on fresh dung, was more in the wet season and male butterfies tended to puddle more than females, supporting the notion that dung puddling by butterfies is for obtaining minerals, especially sodium. Introduction Silva & Williams 2001) but also plays a role in the reproductive behaviour of some butterfies. Lepidopterans are mainly nectar feeders, yet they can have extremely diverse food habits An important criteria in food selection by especially in the tropics (Adler 1982; Sourakov herbivores is the nitrogen content of plants (Ball et al. 2012). The diversity of food habits is et al. 2000) as it is required for protein synthesis. related to ecological and biological differences Animals excrete nitrogen metabolites to the within the group. Unlike the larvae which have environment through dung and urine (Ball et al. specifc food requirements, adult butterfies are 2000). Obtaining nitrogenous compounds such opportunistic feeders and in addition to fower as amino acids, albumin, and casein, is another nectar, are capable of obtaining nutrients from a reason for puddling (Boggs & Gilbert 1979; variety of substrates such as mud, carrion, rotten Beck et al. 1999). fruits, tree sap, perspiration and dung (Downes 1973; Boggs & Jackson 1991; Molleman 2010). Besides lepidopterans, different bee species also engage in puddling behaviour. For example, The phenomenon of feeding on non-nectar honey bees, sweat bees (Butler 1940) and sources by lepidopterans is termed “puddling”, stingless bees (Bänziger et al. 2009) are known presumably derived from reference to feeding on to puddle on sweat and tears. mud-puddles (Molleman 2010). This paper presents observations of lepidopterans Puddling provides butterfies with nutrients, puddling on Asian elephant (Elephas maximus) which are scarce in nectar (Molleman et al. dung, which has previously been recorded only 2005). Lepidopterans acquire a limited amount of in two species of butterfies; Malayan and Lesser minerals during the herbivorous caterpillar stage Grass Blue (Hewavitharana et al. 2013). that is sequestered and used in subsequent life stages. Behavioural adaptations such as puddling Methodology enable them to obtain a balanced mineral intake, overcoming shortfalls in larval nutrition. One of Study area the main minerals obtained through puddling is sodium, which is important for neuromuscular Our study area borders the south-western part function and regulating fuid balance (Fraústo da of the Wasgamuwa National Park, Sri Lanka. © 2017 The Authors - Open Access 14 The area includes different habitat types such Results as chena (slash-and-burn cultivation), lake beds, agricultural felds, home gardens, scrub lands, In a total of 148 days of observation, puddling secondary forests and dry-mixed evergreen was observed on nine days, on nine of 978 dung forests. piles examined. A total of 26 species of butterfies from fve families were observed puddling (Figs. The climate of the study area is tropical, with a 1, 2 & 3): Lycaenidae (9 species), Pieridae (7 dry season extending from March to September species), Nymphalidae (4 species), Papilionidae and a rainy season from October to February. (4 species) and Hesperiidae (2 species). Mean From May to August the region experiences high number of species recorded per dung pile was winds. The mean temperature is 32˚C and the 3.78 ± 4.3 (range 1–15). mean annual rainfall is 2250 mm, which occurs mostly during the northeast monsoon. The most frequently observed species were Common Hedge Blue and Lesser Grass Blue The region is situated in lowland Sri Lanka, and both lycaenids, which were recorded on four has an elevation gradient of 125–300 m a.s.l. occasions. The lycaenids, Indian Cupid and Lime The terrain of the study area is predominantly Blue, and the pierid, Common Grass Yellow were fat with some low-undulating areas and elevated recorded on two occasions. All other species rock outcrops. were observed only once (Table 1). The number of individuals per dung pile varied from 45 to 1 Data collection (mean 8.57 ± 5.9). The most number of individuals of a single species recorded from a dung pile was Dung–puddling was opportunistically recorded in the Lemon Emigrant (n = 45) followed by the 2013, 2014, and 2016, while conducting elephant Common Gull (n = 21), both pierids, and the dung transects. When puddling butterfies were Common Jay (n = 17) a papilionid. The highest encountered, the species, their numbers, and sex number of species recorded on a single dung pile were recorded. Butterfies were photographed was 12 and represented all fve families. using a Nikon-Coolpix P510 camera and sexed using wing characteristics. Of 169 individual butterfies observed puddling across all species, 91% were males and 9% Habitat types were classifed as reservoir bed females. Recorded females were of Common grasslands, tall grass, scrublands, closed forests, Albatross, Common Gull, Common Pierrot and agricultural felds and home gardens based on Lemon Emigrant. visual characteristics. The habitat type where dung piles were located was recorded. All the puddling in dung piles occurred in scrubland (56%) and in reservoir grass beds Dung was categorized as “fresh” or “old” where (44%). No puddling incidents were observed dung piles deposited within an approximately in tall grass, closed forest, home gardens and 48-hour period was considered as “fresh”. agricultural felds. Puddling incidents in the wet Characteristics used to identify fresh dung were; moist outer surface, distinct odour, lighter colour, and the presence of fies. In order to assess seasonality of puddling in dry and wet seasons, we created a puddling index for each season by dividing the total number of puddling incidents by the total number of dung piles observed in each season, then averaged to a month. Figure 1. Number of butterfy species recorded in each family. 15 Figure 2. Butterfy species that were recorded in family Pieridae (a–g) and Lycaenidae (h–p). a = Common Gull; b = Lemon Emigrant; c = Mottled Emigrant; d = Common Albatross, e = One-spot Grass Yellow; f = Common Grass Yellow; g = Small Grass Yellow; h = Indian Cupid; i = Common Pierrot; j = Common Hedge Blue; k = Lesser Grass Blue; l = Common Lineblue; m = Malayan; n = Tailless Lineblue; o = Plains Cupid; p = Lime Blue. season was 0.3 incidents per month whereas in nine dung piles on nine days. This suggests that the dry season it was 0.09 incidents per month. puddling on elephant dung, and its use as a food All observations were from fresh dung piles with substrate by butterfies is not common. no puddling events being observed on old dung piles. All the butterfy species we recorded on elephant dung mainly feed on nectar. Of these, 35% Discussion belonged to Lycaenidae, which also has the highest representation among butterfies in Sri In the observation of 978 individual dung piles Lanka with 34% of species. Lycaenids in general, over 148 days, we only observed puddling on utilize a variety of food sources (Krenn 2008). Of 16 Figure 3. Butterfy species that were recorded in family Nymphalidae (q–t), Papilionidae (u–x) and Hesperiidae (y–z). q = Great Eggfy; r = Lemon Pansy; s = Chocolate Soldier; t = White Four-ring; u = Common Jay; v = Common Mormon; w = Lime Butterfy; x = Spot Swordtail; y = Golden Angle; z = Indian Skipper. the nine lycaenids observed puddling on elephant Gull, Lemon Emigrant and Mottled Emigrant dung by us, only the Lesser Grass Blue and the congregating on elephant dung, displaying Malayan have been previously reported to do so greater gregariousness than other butterfies in (Hewavitharana et al. 2013). Among the others, dung puddling also. the Common Hedge Blue, Common Lineblue and Tailless Lineblue have been reported to feed The four species of papilionids that we recorded on scat and bird droppings (van der Poorten & on elephant dung have been observed to mud van der Poorten 2016). The Common Pierrort sip especially during dry and hot weather (Rima was thought to seldom feed on dung (Rima et al. et al. 2016; van der Poorten & van der Poorten 2016; van der Poorten & van der Poorten 2016). 2016), but no previous records were found on the The Indian Cupid, Lime Blue and Plains Cupid use of other substrates as food sources by them. have been reported to puddle on mud (van der Poorten & van der Poorten 2016) but not on other Amongst the recorded nymphalids, the Great substrates. Eggfy and Chocolate Soldier are known to feed on tree sap and fruits (van der Poorten & van While pierids are known for mud sipping, they der Poorten 2016). Although the Lemon Pansy were not previously reported to feed on elephant imbibes liquids from the soil, they have not been dung. Pierids congregate in large numbers in wet recorded to feed