Impact of land use pattern and seasonality on butterfly diversity in a sub-tropical Terai arc landscape (TAL), Pantnagar, Uttarakhand (India)

Species diversity and richness of butterflies in habitats constituted by different land-use patterns were studied in the Terai region of Pantnagar for 2 years from Nov 2017 to Dec 2019. A total of 92 species of butterflies belonging to 66 genera and five families were documented from three different habitats viz., inhabited settlement, agricultural land and secondary forest. Family Nymphalidae (34.13%) dominated over Lycaenidae (28.88%), Pieridae (26.20%), Papilionidae (8.76%) and Hesperiidae (4.04%). Among the different species of butterflies, Pseudozizeeria maha was the most dominant butterfly with 6.09% relative abundance followed by Pieris canidia (5.20%), Eurema hecabe (4.86%), Ariadne merione (3.42%), Catopsilia pomona (3.21%) and Luthrodes pandava (3.01%). Diversity and evenness indices viz., Margalef's index (D-mg), Shannon diversity index (H') and Pielou's J revealed a greater diversity in undisturbed secondary forest rich in host and nectar plant than the habitat intervened with crop cultivation. Three-factorial ANOVA showed a significant variation in abundance of butterfly concerning months, site and butterfly families. Pearson's correlation showed the existence of a positive correlation between butterfly abundance and weather parameters viz., maximum temperature, morning and evening relative humidity and rainfall. The results obtained indicate that the Pantnagar region holds a splendid diversity of butterflies and the diversity is altered by different land-use pattern. Regular survey and monitoring of the region are suggested for conservation and documenting the changing biodiversity.