October 2012 - Journal of Threatened Taxa

JoTT Co m m u n ic a t i o n 4(12): 3085–3102Lowland forest butterflies of the Sankosh Rivercatchment, BhutanArun P. SinghEcology and Biodiversity Conservation Division, Rain Forest Research Institute (ICFRE), P.O. Box no. 136, Deovan, Sotai, Jorhat,Assam 785001, IndiaEmail: ranoteaps@gmail.com, singhap@icfre.orgDate of publication (online): 10 October 2012Date of publication (print): 10 October 2012ISSN 0974-7907 (online) | 0974-7893 (print)Editor: Ullasa KodandaramaiahManuscript details:Ms # o2625Received 12 November 2010Final received 17 July 2012Finally accepted 20 August 2012Citation: Singh, A.P. (2012). Lowland forestbutterflies of the Sankosh River catchment,Bhutan. Journal of Threatened Taxa 4(12):3085–3102.Copyright: © Arun P. Singh 2012. CreativeCommons Attribution 3.0 Unported License.JoTT allows unrestricted use of this article in anymedium for non-profit purposes, reproduction anddistribution by providing adequate credit to theauthors and the source of publication.Author Details: Ar u n P. Si n g h works on theconservation of biodiversity of Himalaya withspecial reference to butterflies and birdssince 18 years. His research works includeecology, taxonomy, and environmental impactassessment (EIA) studies. Presently, he headsthe Ecology and Biodiversity ConservationDivision, Rain Forest Research Institute(ICFRE), Jorhat, Assam.Acknowledgements: This study was part ofthe EIA of the proposed Indo-Bhutan SankoshHydro Electric Power project at Kerabari, beingcarried out by the Indian Council of ForestryResearch and Education (ICFRE), Dehradun.The author is thankful to DG (ICFRE), DDG(Extension, ICFRE) & ADG and Sudhir Kumar,project manager (EIA Division, ICFRE),and Director, FRI, India, and Department ofEnergy and Range Officer, Kalikhola, ForestDepartment of the Royal Government of Bhutanfor providing the necessary facilities to carry outthis study.OPEN ACCESS | FREE DOWNLOADAbstract: This paper provides information on butterflies of the lowland forests of Bhutanfor the first time. As a part of the biodiversity impact assessment for the proposedSankosh hydroelectric power project, a survey was carried out along the SankoshRiver catchment to study the butterfly diversity. The aim of the study was to identifyspecies of conservation priority, their seasonality and to know the butterfly diversitypotential of the area. Surveys were carried out during five different seasons (winter,spring, pre-monsoon, monsoon, post-monsoon) lasting 18 days from January 2009to March 2010. Pollard walk method was used to assess the diversity on four-linetransects within 10–12 km radius of the proposed dam site. Two hundred and thirteenspecies, including 22 papilionids, were thus sampled. Eleven species amongst theseare listed in Schedules I and II of the Indian Wildlife (Protection) Act, 1972, of which10 taxa (Pareronia avatar avatar, Nacaduba pactolus continentalis, Porostas alutacoelestis, Elymnias vasudeva vasudeva, Mycalesis mestra retus, Melanitis ziteniuszitenius, Charaxes marmax, Athyma ranga ranga, Neptis manasa manasa and Neptissoma soma) are of conservation priority as they are ‘rare’ in occurrence across theirdistribution range in the region. The maximum number of species (128) were recordedduring the spring season (March) and lowest (66) during July (monsoon). The seasonalpattern of variation in diversity was very typical of the pattern found in other areas of thelower foothills and adjoining plains of the Himalaya. Relative abundances of butterfliesduring spring varied significantly (p