Nutritional dynamics in early development of Asian Openbill: A study of hatchling and nestling feeding patterns

Abstract

Nutrition plays a crucial role in avian development, growth, and health. Inadequate nutrition can have an impact on immune systems and increase susceptibility to diseases. However, there is a paucity of studies that quantify the nutrition provided to young birds. We studied the nutrients delivered to six nests, especially to the hatchling and nestling stages of the Asian Openbill (Anastomus oscitans), using CCTV cameras and spotting scope in Eastern Nepal. Simultaneously, we collected the major food of the Asian Openbill, specifically Filopaludina and Pila spp., and assessed their nutrient content value to estimate the amount of nutrients delivered to the young birds. Asian Openbills feed Filopaludina spp. to hatchlings and both Filopaludina and Pila species to nestlings across all nests. The amount of food supplied to each nest during the nestling stage (272.4 to 386.4 g/day) was approximately three times higher than that during the hatchling stage (87.7 to 128.01 g/day). Energy was primarily derived from protein, followed by fat, and carbohydrate, with variations observed between both nesting stages. Our study provides baseline data on nutrient delivery patterns during two nesting stages of the Asian Openbill in Eastern Nepal, highlighting their adaptability and flexibility in meeting nutritional requirements.