Abstract

Butterflies are attractive insects that have aesthetic value and are biological indicators,
as they are highly sensitive to changes in environmental conditions. The study was conducted
to document the species diversity and abundance of butterflies in the Betana wetland, Belbari,
Morang, Nepal, from March to May 2024, using line transects and the Pollard walk methods.
Three transect routes, each 500 meters in length, were designed and observed on sunny days.
A total of 1124 butterfly individuals, representing 65 species, 43 genera, 14 subfamilies, and
six families, were recorded. The Nymphalidae family showed the highest species richness (28
species), followed by Lycaenidae (12), Pieridae (9), Papilionidae (8), Hesperiidae (7), and
least by Riodinidae (1). The family Nymphalidae, with 543 species, had the highest butterfly
abundance, while Riodinidae, with 14 species, showed the lowest abundance. The Shannon
Diversity Index (H = 3.60), Pielou’s Evenness (E = 0.86), and Margalef’s Richness Index (D
= 9.11) indicated a high level of butterfly diversity, a balanced community, and a stable
ecosystem in the study area. The results of the present study could be a foundational
reference for future butterfly research in the Betana wetland of Belbari, Morang, Nepal.