BirdLife International factsheet for White-bellied Sea-eagle
White-bellied Sea-eagle is a Pacific raptor, with a range that stretches from western India through Indonesia to Australia (BirdLife International, 2020). The global population is estimated to be 1,000 – 10,000 individuals (Ferguson-Lees and Christie, 2001), which roughly equates to 670-6,700 mature individuals.
This species is threatened by human disturbance, including shooting and poisoning, and loss of breeding habitat (Ferguson-Lees and Christie, 2001). Previously, White-bellied Sea-eagle has been considered Least Concern, but a re-evaluation of its population size means this classification is no longer tenable and thus a complete reassessment of Red List category is required. We have therefore reassessed this species against all the criteria below.
Criterion A: The population trend for this species has not been calculated. We therefore cannot assess White-bellied Sea-eagle under Criterion A.
Criterion B: The Extent of Occurrence (EOO) for this species is >20,000 km². This species does therefore not qualify as threatened under this category, and so may be considered Least Concern under Criterion B1.
Criterion C: The global population size for White-bellied Sea-eagle is estimated to be 670-6700 mature individuals. This reaches the threatened threshold (<10,000 mature individuals), but in order to fully qualify for threatened status under criterion C, other sub-criteria must be met. White-bellied Sea-eagle is believed to be experiencing a continued decline from human disturbance and habitat loss, but it is not known to be undergoing any extreme fluctuations. While the mature individuals are not believed to exist solely in one subpopulation, the subpopulation structure remains unknown. If it transpires that <1,000 mature individuals are present in the largest subpopulation, then this species would qualify as threatened. At the moment, it does not fully qualify as Vulnerable under criterion C. We therefore seek any information about population structure: how many subpopulations are there, and how many individuals are in each one?
Criterion D: The global population size for White-bellied Sea-eagle is estimated to be 670-6700 mature individuals. Assuming the true population size is nearer the lower end of the estimate, this meets the threshold (<1000 mature individuals) for classification as threatened under this criterion. This species may therefore be considered Vulnerable under Criterion D1.
Criterion E: To the best of our knowledge, no quantitative analysis has been carried out on this species. We therefore cannot assess White-bellied Sea-eagle under criterion E.
We therefore suggest that White-bellied Sea-eagle (Heliaeetus leucogaster) be listed as Vulnerable under Criterion D1. We welcome any comments to the proposed listing.
Please note that this topic is not designed to be a general discussion about the ecology of the species, rather a discussion of the species’ Red List status. Therefore, please make sure your comments are relevant to the species’ Red List status and the information requested. By submitting a comment, you confirm that you agree to the Comment Policy.
An information booklet on the Red List Categories and Criteria can be downloaded here and the Red List Criteria Summary Sheet can be downloaded here. Detailed guidance on IUCN Red List terms and definitions and the application of the Red List Categories and Criteria can be downloaded here.
BirdLife International (2020) Species factsheet: Haliaeetus leucogaster. Downloaded from http://www.birdlife.org on 18/05/2020.
Ferguson-Lees, J., and Christie, D.A., 2001. Raptors of the World. Christopher Helm, London.