Waterbird Density and Habitat Utilisation Pattern in Wular Lake, Kashmir, India

Jahangir Ahmad Dar,Mohmad Muzafar Sheikh,Mustahson Farooq Fazili,Ishfaq Nazir Wani,Bilal Ahmad Bhat

doi:10.17485/ijst/v14i19.1781

Abstract

Background: Understanding abundance, diversity and density of waterbird species along with detailed description of habitat utilization pattern is significant to understand species ecology and consequently for management and conservation. Waterbird density and their utilisation pattern of different habitats in Wular lake was investigated during study period from 2017-2019. Methods: Population estimation of waterbirds was carried out by point count and line transect method. Length of the transect varied from 50-100 meters. Waterbird density was estimated using Reynolds formula in a circular plot. Radius of circle varied from 45- 50 meters. Pattern of habitat utilisation was calculated by Ivlev’s index. Findings: Twenty-five (25) species of waterbirds belonging to eighteen (18) genera, seven families (7) and six orders (6) were recorded. Mean population of 628193874.20 during mid-winter and 420.58142.10 individuals during post winter was observed. Mean density of 810.81387.3 birds ha-1 during mid-winter and 71.291.33 birds ha-1 during post winter was recorded. Of all the habitats, open water had highest waterbird density (630.3258.32 birds ha-1) while as paddy fields had lowest waterbird density (0.440.08 birds ha-1) during mid-winter. During post winter also open water habitat was the most densely populated habitat (30.24.85 birds ha-1) but marshes were least densely populated habitat (0.410.05 birds ha-1) during this season. Open water habitat was most preferred habitat and peatlands the most avoided one. Variation in densities among different habitats was statistically significant (p<0.05). Novelty: Anthropogenic threats like agricultural conversion, habitat degradation and pollution greatly affect the utilisation of different habitats by waterbirds. Knowledge indicating the density and diversity of waterbirds along with their preference and avoidance towards different habitats will help in managing those habitats as well as framing conservation policies for survival of waterbirds inhabiting them. Keywords: Habitat utilisation; Density; Population; Ramsar; Waterbirds; Wetlands; Wular

Highlights

Wetlands harbouring diverse biological communities with extensive ecosystem services such as water purification, flood abatement and climate regulation provide habitat for a diversity of animals especially waterbirds [1], [2]
Estimation of abundance of birds was calculated as; Very abundant (VA): over 1000 individuals seen per day; Abundant (A) 201-1000 individuals seen per day; Very common (VC) 51-200 individuals seen per day; Common (C) 21-50 individuals seen per day; Fairly common (FC) 7-20 individuals seen per day; Uncommon (UC) 1-6 individuals seen per day; Rare (Re) 1-6 individuals seen per season; Very rare (VR): infrequent occurrence [34], [35]
For determining the density of waterbird circular area with radius of 50-70 m was scanned within habitats and density was calculated using Reynold’s formula [36] : D = n × 1000/πr2 where n = number of individuals π = 3.1415 r = radius of the area under observation A total of 38 transects (500-1000 m) were laid systematically to cover whole area of wetlands

Summary

Introduction

Wetlands harbouring diverse biological communities with extensive ecosystem services such as water purification, flood abatement and climate regulation provide habitat for a diversity of animals especially waterbirds [1], [2]. Waterbirds are usually considered sensitive indicators of wetland health and biodiversity [5,6,7,8,9] and their abundance and diversity are often used as criteria to identify and qualify wetlands of international importance and to designate them as protected areas [10,11,12] Their population trend, diet and habitat utilisation pattern can be used for monitoring changes in wetland ecosystems [13], [14]. Understanding abundance, diversity and density of waterbird species along with detailed description of habitat utilization pattern is significant to understand species ecology and for management and conservation Waterbird density and their utilisation pattern of different habitats in Wular lake was investigated during study period from 2017-2019.

Methods

Results

Discussion

Conclusion