Jounwl of Ecological Society Vol. 13/14 : 40-45 (2000-2001) Butterfly Diversity of Pune City along the Human Impact Gradient Krushnamesh Kunte sides nectar plants, predators and early stages of Introduction butterflies. India hosts 1,501 species of butterflies (Gaonkar 1996), of which peninsular India hosts 350, and the Results And Discussion Western Ghats, 331. Pune falls in the relatively spe­ Diversity and distribution: The annexure depicts cies-poor, drier region of the northern Western Ghats. the distribution patterns of 104 butterfly species re­ Above literature on biogeographic distribution and corded so far. Some butterfly species, which perhaps habitat preference indicates that the Pune district may evaded detection or precise field identity, may include harbour about 170 species (Kunte, unpubl.), of which Lineblues, other Blues, Swifts and Skippers. Further 103 are so far reported from Pune urban area within a survey may not record more than 120 species from the 20 km radius. Remaining species are mostly forest study area. Table 1 summarises the annexure in terms dwellers and may not be found in the urban area. of habitatwise species richness and uniqueness. Ov~ There is hardly any literature specific to Pune butter­ two thirds are found in denser forest habitats such 11.Y flies . valleys of Sinhagad and Peacock Bay, 11 of whichla're found nowhere else. Scrub appears to be most species Methodology rich habitat frequented by three fourths of the species While observations here are based on seasonal though only two of these were exclusive to it, seldom visits to many localities in and around Pune, the recorded elsewhere. Forest, on the other hand har­ author explored six sites more intensely, given their boured a bit lower diversity with only two thirds the contrasting vegetation types and levels of disturbance species, but highest level of uniqueness, with nearly a (Kunte, 1997). The sites include the moist deciduous dozen species exclusive to it. Plantations also har­ forests at Sinhgad hills; forests and grasslands prone boured two unique species, though low species rich­ to fire and grazing, amidst deserted habitation around ness. Agriculture and grassland harbour high and NDA; much drier, fire prone scrub and grasslands lowest species richness respectively though without with little grazing, besides afforestation at Pachgaon, any species being exclusive to them. Together, wilder­ highly grazed but hardly burnt grasslands (so called ness areas i.e. forest, scrub and grasslands harbour 'barren land') at Malwadi; well-wooded campus of three fourths of the species, about a fourth of them S.P. College with profusion of old, native trees, be­ being exclusive to wilderness zone. The plantations sides exotics ones, amidst a mosaic of concrete build­ clinging the township, along with the agriculture rep­ ings, the marshes and scrub along the Mutha riverbank resent more human impacted zone which harbours at Dattawadi. Besides noting relative abundance and about two thirds of the total species recorded from even seasonal counts (Kunte,1997), the author also Pune, but some of them have their larval food plants recorded larval host plants and their phenology, be- located in the wilderness zone. The habitat specialists 4024, Survey No. ]4/ 4, Warje, Pune 4110 29. Email: [email protected] 40 BUITERFLY DIVERSITY OF PUNE CITY ALONG THE HUMAN IMP ACT GRADIENT Table 1 Habitat-wise species richness at Sinhagad). Although with little fluctuations, a few species (e.g. Common Evening Brown at Sinhagad) No. of No. of have similar abundance throughout the year. Most total species Unique·Species butterflies, in terms of number of individuals and number of species, fly in Pune during late monsoon Forest (F) 68 11 and winter. The populations are low in spring and Scrub (S) 76 2 summer, probably due to fires at Peacock Bay and Grassland (G) 38 0 Pachgaon, and scarcity of water and ground flora at Plantations (P) 57 2 Malwadi and Sinhagad. Usually at all the sites, the Agriculture (A) 69 0 populations start building from early monsoon and Wild (F,S,G) 80 20 show the first peak in late monsoon, followed by a Impacted (P,A) 70 0 second peak in winter. Fire and grazing impacts: Certain hillocks in Pune are grazed by migratory herds of sheep and resident livestock. Some are annually burned in un(:ontrolled include predominantly forest dwellers like the and artificial fires. Intense grazing seriously alters the Bushbrown, few species of Yellows and Flats; while composition of ground flora in grasslands. Cattle up­ the Tailed Jay is a habitation speCialist. The habitat root grasses while feeding on them, and therefore generalists include Common Rose, Lime Butterfly, decrease their density, promote unpalatable herbs, at species of Grass Blues etc. found in a variety of habitat the cost of tall grasses such as at Malwadi. On the types. other hand, the fire-afflicted site of Pachgaon hosts tall Seasonality: Table 2 presents th~ number of total grasses but herbs are rare. Given these difference in species recorded along transects at foui localities larval and adult food resources, the butterfly fauna of (Kunte, 1997) across seasons. This excludes sepcies Malwadi grasslands differs from the Pachgaon with uni"eliably low abundances and the plantation grasslands. For instance, species such as Grass Blues, fauna. Kunte (1997) describes in detail the seasonality Grass Jewel, Joker and Blue Pansy are much more patterns, technically termed flight periods, of species common mainly at the fire-free site of Malwadi than and groups, including factors affecting it. Butterflies Pachgaon, especially during winter. Since larval as &. in aU habitats have distinct flight periods. Almost all well · as imaginal stages of these butterfly species ~Iii('•. butterflies have very short seasonal peaks, and they inhabit extremely disturbed vegetation, it is possible "<Y 'are either absent or rare in other seasons. However, that they have evolved in secondary, disturbed their interesting patterns probably reflect phenophases grasslands. Fire can occur naturally or be initiated by of their host plants. Some species occur throughout human beings. It plays a very important role since it the year with a short population peak in a specific affects the vegetation directly. However, despite af­ season, and some species occur only for a few months, fecting species composition, fire does not seem to such as the Spotless Grass Yellow and the Common affect the species richness (Table 2). Butterflies such as Hedge Blue, respectively (at Sinhagad). A few species common evening brown, plains cupid, spotless grass have a single, short flight period such as Lineblues (at yellow, blue pansy, lemon pansy, painted lady and Sinhagad) whereas some have two short peaks (e.g. leopard were found at fire-free as well as at fire-afflicted Common Five-ring at Sinhagad). Yet others have just sites. These species had more intense peaks at one, but fairly long flight period (e.g. Chocolate Pansy fire-afflicted areas with highly seasonal occurrence. Table 2 Seasonal variation in species richness at the four sites Feb;-Mar. Apr.-May Jun.-Jul. Aug.-Sep. Oct.-Nov. Dec.-Jan. Sinhagad 8 7 17 19 16 14 Peacock Bay 6 6 7 14 19 12 Pachgaon 4 3 14 25 18 21 Malwadi 14 8 10 14 18 12 41 JOURNAL OF ECOLOGICAL SOCIETY On the other hand, in the fire-free areas their occur­ whether herbs or climbers, rather than planting exotic rence was less seasonal and spread across more sea­ trees. Controling hill fires is also a pressing need. sons. Control of annual fires will be a singular, and perhaps the most important, effort at conserving but­ Acknowledgements terflies in Pune. Radhika Godbole helped me during the fieldwork Population changes: In the absence of earlier stud­ while Dr. Makarand Dabak and Thomas Gay shared ies, it is impossible to quantify if certain butterfly their perceptions especially about the past records. population have increased or decreased over the last My teachers such as Dr. Pendse of S. P. College decades. It is obvious that loss of the habitat and the encouraged this extracurricular interest that cost my increased use of the inorganic pesticides in recent college schedule. I thank them all, besides my coop­ decades have adversely affected many butterfly spe­ erative family and friends. cies. Yet, no species might have gone locally extinct in Pune, given the long history of modification of the Bibliography land in this region. In contrast, populations of at least Evans, J. H. 1932. Identification of Indian Butterflies. two butterflies, evergreen and semi-evergreen forest BNHS (repr.). Mumbai. dwellers viz. Blue Mormon and the Plain Puffin have Gaonkar, H. 1996. Butterflies of the Western Ghats increased prominently in the last 10 years, thanks to with notes on those of Sri Lanka. A report to the home gardens that host their larval host plants viz. Centre for Ecological Sciences, Indian Institute of Citrus spp. and Drypetes roxburghii respectively. Com­ Science, Bangalore; Zoological Museum, Copen­ mon Albatross and the Plain Puffin both feed on D. hagen and Natural History Museum, London. roxburghii and co-occur at the probable source popula­ Kunte, K. J. (unpbl.) Checklist of the Butterflies of the tion, in Bheemashankar in the Western Ghats. But so Western Ghats. far only the Plain Puffin has been successful in estab­ Kunte, K. J. 1996. Strange behavior of Mottled Emi­ lishing in the drier east of Pune while only the Com­ grant males. J. Bombay Nat. His. Soc., 93(2) : 307- mon Albatross has established itself in parts of moister, 308. western Mumbai city. Populations of the Tailed Jay Kunte, K. J. 1997. Seasonal patterns in butterfly abun­ and the Common Mormon from the evergreen and dance and species diversity in four tropical habi­ deciduous forests respectively seem increasing, ben­ tats in northern Western Ghats.