Seasonal variation in feeding behaviour and foraging success of Indian pond heron (Ardeola grayii) in different habitats

Akanksha Dwivedi

doi:10.17485/ijst/v13i22.473

Abstract

Objectives: The present study was focused on feeding behaviour and foraging success of Indian pond heron (Ardeola grayii) in different seasons and habitats. Methods: The study was carried out in three habitats, lake, pond and marshy area from September 2016 to December 2017. All activities such as feeding behaviour, foraging success, prey abundance, success ratio, feeding frequency (foraging attempt and success) of A. grayii were compared in three habitats with three seasons by using binocular and video recorder. Statistical analysis: Data were analysed by SPSS (21 version) and graph pad prism. In this study, prey abundance and foraging success in three habitats and season differed statistically significant (p < 0.05). By using non-linear regression on foraging attempt and success in three habitats three curve (exponential, cubic, growth and power) best fitted to analyzed data sets. These curve shows variation in feeding pattern. Findings: Stand and wait is dominant feeding behaviour followed by walk slowly and walk quickly in all three habitats and season. Prey was abundantly present during monsoon, as a result feeding frequency and success ratio maximized. Structure of habitats, vegetation, and water depth also influenced foraging success of Ardeola grayii. Thus, overall finding showed that Indian pond heron feeding behaviour and foraging success affected by structure of habitats and seasons. Keywords: Habitat; season; feeding; frequency; behaviour; prey

Highlights

Feeding is a crucial activity of the bird’s life which is vital for its survival the demands of food acquisition impose significant challenges to both physiology and behaviour of birds
Five types of prey items were recorded in three feeding habitats of A. grayii ( Table 1)
We found that stand and wait was frequently used behaviour followed by walk slowly, walk quickly, crouched position, diving, bill dipping, neck movement, hopping and probing at different habitats ( Table 5)

Summary

Introduction

Feeding is a crucial activity of the bird’s life which is vital for its survival the demands of food acquisition impose significant challenges to both physiology and behaviour of birds. The members of family Ardeidae are medium to large wading birds, consist of 9 species viz. Dwivedi et al / Indian Journal of Science and Technology 2020;13(22):2203–2213. Ardeola grayii (Indian Pond Heron), Nycticorax nycticorax (Black-crowned Night Heron), Ardea cinerea (Grey Heron), Ardea purpurea (Purple Heron), Egretta garzetta (Little Egret), Bubulcus ibis (Cattle Egret), Mesophoyx intermedia (Median egret), Casmerodius albus (Large egret) and Ixobrychus cinnamomeus (Chestnut Bittern). All those large wading birds captured prey by employing stand and wait for strategy [1; 2], or by walking slowly towards the prey and waiting for surprise attack [3]. Feeding behaviour and feeding frequency of herons are affected by several factors, including; prey density and prey availability [8], seasons [9], habitat characteristics [10] and height of vegetation [11]

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