Human activity has likely erased more bird species than previously estimated, possibly affecting around 1,430 distinct kinds. These figures, derived from statistical modeling and reported in Nature Communications, reveal a broader scale of extinctions caused by humans than earlier work suggested.
Observations and fossil records to date indicate that about 600 bird species have disappeared since humans began dispersing across the globe at the end of the Pleistocene, with roughly 90 percent of those losses tied to islands under human influence. Notable examples range from the famous Mauritius dodo to the North Atlantic great auk. More recent losses are documented in places such as the Canary Islands, where the monochrome oystercatcher Haematopus meadewaldoi once lived, or the Triassic greenfinch Carduelis triasis, as well as the Ibiza railway Rallus eivissensis in the Balearic Islands.
According to the new paper and its statistical framework, the net number of extinct bird species may be a little more than double the prior estimate: around 1,430 species, representing roughly 11 percent of all bird species once known to exist.
Islands were once sanctuaries of pristine biodiversity. Yet human arrival in remote locations such as Hawaii, Tonga, and the Azores, as well as in the Canaries and Balearics, set off long-lasting effects. Deforestation, overhunting, the transportation of invasive species, and other disturbances have driven many island bird populations to extinction and reshaped entire ecosystems over time.
This trend has been chronicled since the 1500s. Before that era, information about species fates came primarily from fossils, leaving large gaps in our knowledge. The absence of fossils means we still cannot fully measure past extinctions, and data quality varies widely across regions.
A research team led by the UK Centre for Ecology and Hydrology along with CREAF employed data on known extinctions and projected them to estimate how many more species might have vanished if a broader survey, similar to New Zealand’s comprehensive documentation of pre-human avifauna, had occurred. New Zealand is cited as the only large region where the pre-arrival bird fauna is believed to be fully documented with well-preserved remains of all species that once thrived there.
Causes of extinction
UKCEH modeler Rob Cooke notes that humans have rapidly reduced bird populations through habitat destruction, overexploitation, and the introduction of rodents, pigs, and dogs. Nest predation on islands lacking native predators has also contributed, and some species disappeared before any written records existed.
CREAF researcher and study co-author Ferran Sayol adds that historic extinctions likely disrupted ecosystem functioning. The loss of birds means the loss of critical services such as seed dispersal and pollination, which can trigger cascading effects across communities and ecosystems.
Currently documented extinctions include three in Spain from the Balearic Islands, all from Ibiza, and ten in the Canary Islands. The model predicts three additional Balearic extinctions and eight more in the Canary Islands that remain undocumented at present.
Three major mass extinctions
Researchers describe several of the most significant human-caused vertebrate extinction events in recent history. The earliest occurred in the Eastern Pacific, including the Hawaiian Islands, in the 14th century, when about 570 bird species vanished after human arrival—nearly a hundred times the natural extinction rate.
The second wave happened in the ninth century BCE, primarily with human expansion into the Western Pacific, including the Fiji Islands. The ongoing crisis today began in the mid-18th century, intensifying with deforestation and the spread of invasive species. Climate change, industrial agriculture, and pollution add to the threats, and models suggest up to 700 bird species could vanish in the coming centuries if current trends persist.
Ferran Sayol concludes that while the rise of species loss is tragic, efforts to conserve and restore habitats have shown results. The Mauritius kestrel and the California condor stand as examples of successful interventions, and the authors emphasize the need to widen habitat protection to prevent future extinctions and preserve ecosystem functions.
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Note: this synthesis draws on ongoing environmental assessments and peer-reviewed research across multiple regions to illuminate global extinction dynamics and the potential for restoration and conservation planning.