One in eight of the world’s bird species is deemed globally threatened and the fortunes of 217 Critically Endangered species are now so perilous that they are at risk of imminent extinction. Some of these species have not been sighted for many years and may already have succumbed. Despite this, there is cause for optimism. Conservation works. Around the world dedicated conservationists—many from within the BirdLife Partnership—have orchestrated spectacular recoveries, bringing numerous species back from the brink. The message is clear: given sufficient resources and political will, species can be saved and the loss of biodiversity reversed.
The IUCN Red List is an objective and authoritative system for evaluating the global conservation status of species and categorising them according to their risk of extinction. To date, over 55,000 species of plants and animals have been assessed and their status determined (see figure). BirdLife International is the official Red List Authority for birds, tasked with evaluating the status of the world’s entire avifauna and keeping these data up to date. As of 2015, BirdLife has established that worldwide 1,375 bird species (13% of the total, or roughly one in eight) are threatened with extinction (). These species have small, fragmented or dwindling ranges (), tiny populations (), or are declining rapidly (). Of these, 217 species are considered Critically Endangered and face an extremely high risk of extinction in the immediate future.
Although threatened bird species are found across the globe, the greatest concentrations occur in the forested tropics (). Some regions hold particularly high numbers of threatened species, for example, the tropical Andes, Atlantic Forests of Brazil, eastern Madagascar, and the archipelagos of South-East Asia (, ). A disproportionately high number of threatened species, almost half, occur on islands, particularly oceanic islands far from land (). For seabirds, the greatest concentrations of threatened species are found in the southern oceans, notably around New Zealand ().
Despite global conservation efforts, the overall status of the world’s birds continues to worsen. Of the world’s threatened species, over 80% have populations that are currently in decline () and there have been some truly catastrophic recent population collapses (, ). For long-lived, slow-breeding species, such as albatrosses, however, even relatively slow population declines can have alarming consequences ().
The IUCN Red List Index (RLI) for birds tracks the movement of species through categories of extinction risk. It reveals a steady and ongoing deterioration in the status of the world’s species since the first comprehensive global assessment in 1988 (). The IUCN categories, however, are relatively broad and species often have to undergo substantial changes in order to cross the thresholds between categories. In 2004, BirdLife conducted a ‘snapshot’ survey of over 100 experts in order to get a more complete picture. It revealed that just 11% of threatened species could be judged to be improving in status ().
The RLI for birds can be broken down biogeographically. The results show that although species have deteriorated in all major ecosystems and regions, these changes have not occurred evenly across the globe. Birds associated with Pacific islands, the open ocean and the lowland forests of Asia have undergone particularly sharp declines (, , ).
Birds are impacted by a range of threats—mostly human-derived—with the conversion of natural habitats to agricultural land the most significant (). The pressures associated with farming seem set to intensify as the human population grows and demand for animal protein and biofuels increases ().
Over the last five hundred years, invasive alien species have been partly or wholly responsible for the extinction of at least 65 bird species, making this the most common contributory factor in recent losses to the world’s avifauna (). Invasive species affect around half of currently threatened bird species. Island species are particularly susceptible, with three-quarters of threatened birds on oceanic islands affected by invasive species (). Rats and cats have had far and away the greatest impact, threatening the survival of hundreds of different bird species worldwide, but other species have also had devastating impacts (, , , ).
In 2010, BirdLife confirmed the extinction of Alaotra Grebe Tachybaptus rufolavatus—the latest in a long line of tragic demises attributable to humankind. The coming years will almost certainly bring other sad losses, however, there remains cause for optimism. Given sufficient resources and political will, species can be saved from extinction. The Herculean efforts of conservationists have brought numerous species back from the brink. A recent study showed that at least 33 bird species would have disappeared in the last century, including 16 during 1994–2004 without dedicated conservation action (, ). These include Mauritius Parakeet Psittacula eques, which had been reduced to fewer than a dozen birds in 1986 before targeted intervention led to its spectacular recovery (). California Condor Gymnogyps californianus and Asian Crested Ibis Nipponia nippon reached similarly perilous numbers before intensive reintroduction programmes pulled them back from the edge (, ). Successful conservation interventions such as these can involve a variety of actions, from raising public awareness () to providing supplementary food () and translocating birds (, ).
BirdLife has identified the priority conservation actions needed for all Critically Endangered species and launched a ‘Preventing Extinctions Programme’ in order to ensure they are implemented. To date, the initiative has appointed ‘Species Guardians’—local organisations or individuals responsible for leading initiatives to reverse the fortunes for almost 60 the world’s most imperilled species (). For example, in the Azores, SPEA (BirdLife in Portugal)—the Species Guardian for the archipelago’s endemic Bullfinch Pyrrhula murina—has had huge success in reversing the species’ decline through habitat management and restoration ().
For more detailed information on the BirdLife Preventing Extinctions Programme, see the report; Saving the world’s most threatened birds: the BirdLife Preventing Extinctions Programme.
To access more case studies on threatened birds and BirdLife's work to save them, please click on the following links.
BirdLife's species work
Globally Threatened Bird Forums
BirdLife news story: 2015 IUCN Red List update—vultures, shorebirds and other iconic species
BirdLife news story: 2014 IUCN Red List update—One tenth of bird species flying under the conservation radar
BirdLife news story: 2013 IUCN Red List update—Red List for Birds 2013: Number of Critically Endangered birds hits new high
BirdLife news story: 2012 IUCN Red List update—Threat to the Amazon’s birds greater than ever, Red List update reveals
BirdLife news story: 2011 IUCN Red List update—big birds lose out in a crowded world
IUCN Red List
Compiled 2011, updated 2012, 2013, 2014, 2015
BirdLife International (2015) Spotlight on threatened birds. Presented as part of the BirdLife State of the world's birds website. Available from: http://www.birdlife.org/datazone