Floral preference of Butterflies in National Botanical Garden, Godawari, Nepal

Abstract

Butterflies have particular nectar-feeding preferences based on various floral characteristics including flower shape, color, fragrance, nectar composition and flower size. Different species of butterflies prefer distinct varieties of flowers. The survival, reproduction, and pollination of butterflies are impacted by the floral choices they make. The National Botanical Garden (NBG), Lalitpur Nepal holds a large number of a variety of flowering plants and a stronghold of butterfly population offering a set of suitable conditions to test the floral preferences by butterflies. Therefore, this study was conducted to find the floral preference of butterflies based on flower color, flower size, origin of plants (native or alien), type of plants (herbs, shrubs or tress), and the relation between the proboscis length of butterflies and the corolla tube length of flowers in special flower garden of the NBG. The data collection was done from March 2022 to October 2022 where each day 5 hours data were collected in two seasons (spring and autumn) by direct observation method for 32 days. The study blocks (n = 10) of each 5×5 m² were designed for the observation. From the study, Pink flower abundance was higher in NBG but the butterflies' visitation was more in yellow flowers (45%) followed by white (15%) and orange (14%). There was a significant difference between the total flower count of different colors and visitation of butterflies in both the seasons (F=4.762, p<0.05). Also, the butterflies preferred alien flowers over native flower showing a significant difference (χ xiii

2 = 89.88, p<0.05) in the frequency of butterfly visitation and the type of plant species. Another result suggested that herbs were seemed to be preferred over shrubs indicating the significant difference (χ 2 =8.28. p<0.05) and small flowers were preferred over the large with the significant difference (χ 2 =588.66, p<0.05). Similarly, there was a significant positive association between the proboscis length of butterflies and the corolla tube length of flowers (R 2 =0.8619, p<0.001). Findings of this study helps to provide a baseline information and highlight the diversity of butterfly on the basis of their floral preferences which will be much beneficial for their conservation in future. Therefore, additional research efforts should be dedicated to explore the behavioral patterns of butterflies in the future days.