October 2012 - Journal of Threatened Taxa

Butterflies of Dibang ValleyM.J.GogoiImage 1. Satellite imagery showing areas covered during field study (Map: Rakesh Saur)photography were conducted on a regular basis duringthe day. Occasional surveys were undertaken after16:00hr to locate shade loving butterflies. Searcheswere conducted near water sources, damp patchesin the forest, open sunny areas, blossoming flowersand bird droppings. Searches were also conductedon hill tops, especially in the catchment areas of hillstreams, as well as from top to bottom of hill streamsto record the maximum number of species. Butterflieswere photographed from different angles as often aspossible to obtain sufficient photographs to enablepositive identification of species. Butterfly specieswere identified using the identification keys of Watson(1897), Evans (1932), Talbot (1947), Smith (1994),Pinratana (1985), Haribal (1992), and photographicguides of Kehimkar (2008).Results and DiscussionThe field study resulted in the recording of 294butterfly species belonging to 156 genera, fromDibang Valley (Table 1). This includes 33 speciesof Papilionidae, 26 species of Pieridae, 59 speciesof Lycaenidae, 115 species of Nymphalidae and61 species belonging to Hesperiidae. Noteworthyrare and endangered species encountered were deNicéville’s Windmill Byasa polla which is includedon Schedule I of the Indian Wildlife (Protection) Act(IWPA), (1972); Khaki Silverline Spindasis rukmini isanother interesting species which is also included onSchedule I of the IWPA, (1972).The matter of greatest concern is that Byasa polla,Spindasis rukmini were recorded outside the protectedarea of MWS. The species were recorded in a smallvillage called Chidu near Nizamghat. The area isundergoing deforestation due to increase of settlementsin the area and clearing of land for agriculture.Logging has also been observed on a small scale inthe area. The increasing use of pesticides in the citrusorchards is another concern in the area. Overall, thelast remaining lowland forest of Lower Dibang Valleyis facing a serious threat to its continued existence atpresent. All these raise serious concerns regarding thesurvival of butterflies in the area. The record of suchrare species in the area shows the potential biodiversityof the area and reflects the need for notification of moreprotected areas in Arunachal Pradesh.It is stressed that the present survey covered theperiod from March–June 2011. Doubtless, there will3138Journal of Threatened Taxa | www.threatenedtaxa.org | October 2012 | 4(12): 3137–3160