Notes on a communal roosting of two oakblues (Lepidoptera: Lycaenidae: Arhopala) and the Common Emigrant (Pieridae: Catopsilia pomona) butterflies in Uttarakhand, India

Communal roosting on an over-nightly basis is common in butterflies for resting and for avoiding predation. Having a source of nectar and safeguarding from harsh weather conditions are also notable parameters to consider a site as a potential roosting spot. Roosting differs from a congregation in the fact that the latter happens mainly in the exposed plant part or the oozing out of fluid, which attracts the butterflies to extract chemicals from the same. The current study has been conducted on an Elephant-apple tree Dillenia indica in the New Forest campus of Dehradun, Uttarakhand, India to observe the roosting behaviour of three blue butterfly species, namely: Large Oakblue Arhopala amantes, Indian Oakblue Arhopala atrax, and pierid butterfly Common Emigrant Catopsilia pomona. The roosting observation was first noted during mid-October. The coinciding of the roosting period and the fruiting season of the tree may mark the importance of having a food source in a potent roosting site. Moreover, the site would provide a shady area with dense foliage, which would also include safeguards against predation.