ArticleProceedings of the National Academy of Sciences of the United States of America2021
Global abundance estimates for 9,700 bird species.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 52 papers, 1 of them a synthesis that pooled it.
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Who cites it
52 citing papers in PubMed, 1 synthesis or guideline pooled it.
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- Gut microbiota promote early-life digestive function in songbirds.bioRxiv : the preprint server for biology · 2026Article
- A Genomic Catalog of Migratory Microbiomes from Wild Birds across China's Habitats.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026Article
- Context-dependent plant-bird interactions shape polychory across the antagonism-mutualism continuum.Communications biology · 2026Article
- Survival of a Long-Lived Avian Scavenger: Implications of Age, Season, and Landscape Composition for Mortality Risk.Ecology and evolution · 2026Article
- Pleistocene demographic histories dominate contemporary genomic diversity in a continental radiation of Himalayan-Hengduan songbirds.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- A Comparison of Three Methods for Estimating Abundances of the Globally Endangered African Grey Parrot.Biology · 2025Article
- Multi-layer networks reveal changes in plant-bird interactions driven by invasive species.Communications biology · 2025Article
- Ecology and environment predict spatially stratified risk of H5 highly pathogenic avian influenza clade 2.3.4.4b in wild birds across Europe.Scientific reports · 2025Article
- Mitochondrial Genome Analysis of Philippine Eagles (Ecology and evolution · 2025Article
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- Structure and function of the avian respiratory system.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- A morphometric and stereological study of the chorioallantoic membrane of the developing ostrich (Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Article
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No grant is acknowledged in the PubMed record.
Abstract
Quantifying the abundance of species is essential to ecology, evolution, and conservation. The distribution of species abundances is fundamental to numerous longstanding questions in ecology, yet the empirical pattern at the global scale remains unresolved, with a few species' abundance well known but most poorly characterized. In large part because of heterogeneous data, few methods exist that can scale up to all species across the globe. Here, we integrate data from a suite of well-studied species with a global dataset of bird occurrences throughout the world-for 9,700 species (∼92% of all extant species)-and use missing data theory to estimate species-specific abundances with associated uncertainty. We find strong evidence that the distribution of species abundances is log left skewed: there are many rare species and comparatively few common species. By aggregating the species-level estimates, we find that there are ∼50 billion individual birds in the world at present. The global-scale abundance estimates that we provide will allow for a line of inquiry into the structure of abundance across biogeographic realms and feeding guilds as well as the consequences of life history (e.g., body size, range size) on population dynamics. Importantly, our method is repeatable and scalable: as data quantity and quality increase, our accuracy in tracking temporal changes in global biodiversity will increase. Moreover, we provide the methodological blueprint for quantifying species-specific abundance, along with uncertainty, for any organism in the world.
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