Bird-Tree Associations and Co-occurrence Patterns in Delhi: Implications for Urban Ecological Restoration and Invasive Species Management

Year : 2026 | Volume : 16 | 02 | Page :
    By

    Anjali Bhardwaj,

  1. Student, Department of Geography, Faculty of Sciences, Jamia Millia Islamia, New Delhi, India

Abstract

Urban trees and birds are intertwined indicators of ecological resilience in cities. This study maps citywide bird-tree interactions in Delhi, India, hosting more than 300 avian species. The city was divided into hexagonal grids, and bird-tree data (506 interactions) were collected through field surveys across 131 sites using standardised 1-kilometre transects. Native keystone species like ficus supported the greatest bird diversity, while invasive Prosopis juliflora was widely used for perching and vocalisation. Native trees contributed significantly to bird richness and behavioural diversity, highlighting their restoration priority. This study is among the first to map bird-tree interaction network and assess its relationship in a megacity, combining bird-bird (mean r=0.37), plant-plant (mean r=0.5) and bird-plant (mean r=0.07) with only 5 pairs exceeding (r=0.5) co-occurrence analyses with behaviour-specific observations. This study offers pertinent facts to inform biodiversity-conscious urban restoration policies in swiftly growing cities. By embedding these patterns within an active Prosopis juliflora canopy-lifting programme, it provides rare, management-ready evidence on how native keystone trees and invasive cover jointly structure urban bird communities.

Keywords: Bird-Tree Interactions, Invasive Species, Urban Ecology, Habitat Complexity, Delhi City

How to cite this article:
Anjali Bhardwaj. Bird-Tree Associations and Co-occurrence Patterns in Delhi: Implications for Urban Ecological Restoration and Invasive Species Management. Research & Reviews : Journal of Ecology. 2026; 16(02):-.
How to cite this URL:
Anjali Bhardwaj. Bird-Tree Associations and Co-occurrence Patterns in Delhi: Implications for Urban Ecological Restoration and Invasive Species Management. Research & Reviews : Journal of Ecology. 2026; 16(02):-. Available from: https://journals.stmjournals.com/rrjoe/article=2026/view=249066


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Ahead of Print Subscription Original Research
Volume 16
02
Received 07/05/2026
Accepted 01/07/2026
Published 01/07/2026
Publication Time 55 Days
17

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