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Spatial variation in abundance and threats informs conservation approaches for Endangered Grey Parrots Psittacus erithacus in Nigeria

Published online by Cambridge University Press:  23 April 2026

Ifeanyi Maxwell Ezenwa Open the ORCID record for Ifeanyi Maxwell Ezenwa [Opens in a new window] ,
Christopher Nwani ,
Ulf Ottosson  and
Rowan O. Martin
Ifeanyi Maxwell Ezenwa*
Affiliation:
Department of Zoology and Environmental Biology, University of Nigeria Nsukka , Nsukka, Enugu State, Nigeria World Parrot Trust Africa Conservation Programme, Hayle, UK
Christopher Nwani
Affiliation:
Department of Zoology and Environmental Biology, University of Nigeria Nsukka , Nsukka, Enugu State, Nigeria
Ulf Ottosson
Affiliation:
A. P. Leventis Ornithological Research Institute, University of Jos Biological Conservatory, Jos, Nigeria
Rowan O. Martin
Affiliation:
World Parrot Trust Africa Conservation Programme, Hayle, UK FitzPatrick Institute of African Ornithology, University of Cape Town , South Africa
*
Corresponding author: Ifeanyi M. Ezenwa; Email: ifeanyi.ezenwa@unn.edu.ng
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Summary

Grey Parrots Psittacus erithacus historically have inhabited lowland rainforest, freshwater swamp, mangrove, and wooded savanna across West and Central Africa. Overexploitation for the pet trade and habitat loss have caused significant population declines, leading to their Endangered status on the International Union for Conservation of Nature (IUCN) Red List. However, recent systematic assessments of their conservation status and threats are lacking across significant parts of their range. Between 2018 and 2019, we combined observational surveys along line transects with questionnaires for local residents to explore the distribution, population trends, and threats to Grey Parrots in 28 sites located across the species’ assumed range in Nigeria. During the transect surveys, 253 groups of Grey Parrots were encountered at 19 sites. Of the 228 local residents that were interviewed, over two thirds reported that populations have declined over the last 20 years but reported that declines varied between regions. The prevalence of threats including hunting, poaching of chicks, capture of adults, and logging also varied between regions. Although regions with robust populations had relatively low threat levels, site-level analyses showed no strong link between threat prevalence and population status. Counts at multiple overnight communal roosts also indicated declines. Seasonal variation in local abundance varied between coastal mangrove and inland forest areas suggesting seasonal movements within Nigeria, highlighting the need for a landscape-scale approach to conservation. The study identified key populations and threats as well as baseline data on abundance, providing a basis for the development and implementation of targeted conservation actions and monitoring of Grey Parrots in Nigeria.

Keywords

ConservationEncounter rateGrey ParrotParrot poaching and trappingPopulation density and trends

Information

Type
Research Article
Information
Bird Conservation International , Volume 36 , 2026 , e18
Copyright
© The Author(s), 2026. Published by Cambridge University Press on behalf of BirdLife International

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