For the first time ever, conservationists have a unified global checklist of the species of bird found on Earth, thanks to the publication of AviList.
AviList – a brand-new, unified global checklist of bird species and taxonomy – was published on Thursday, June 12, 2025. Containing 11,131 species, 19,879 subspecies, 2,376 genera, 252 families and 46 orders, this new checklist brings together global thinking on what constitutes a species and shakes up our understanding of the avian world.
Dr Stuart Butchart, Chief Scientist at BirdLife International, said: “The development and adoption of a single unified global taxonomic list for birds will benefit conservation, removing the current confusion and uncertainty resulting from the existence of multiple lists. It will make it easier for birders, scientists, policymakers and conservationists to share information, use and link different online platforms, and share a common understanding of avian distribution, ecology and conservation priorities.”
Until now, ornithologists and birders have used a selection of global checklists, each with its own reasoning on what constitutes a specific species of bird. AviList’s unified view has taken four years of work by the Working Group on Avian Checklists, containing representatives from BirdLife International, the Cornell Lab of Ornithology, the American Ornithologists Society, the International Ornithologists’ Union, and Avibase. The new checklist will replace the International Ornithological Committee (IOC) and Clements lists and will be updated annually.
Dr Paul Donald, BirdLife’s representative on AviList, said: “With hundreds of differences between the various checklists to resolve, each of them requiring the team to pull together and consider all the evidence, the process took almost four years. The process allowed us to develop a whole new perspective on the world’s birds, and AviList should become the standard reference on global avian diversity for decades to come.”
With our conservation work around the globe protecting the most vulnerable species and keeping common birds common, BirdLife International will transition from our current list to AviList over the next few years. This ensures we continue helping populations thrive and the IUCN Red List up-to-speed with the very latest status updates. Once fully aligned, the benefits for sustainable taxonomic work, global authority and clarity on conservation priorities are immense – and BirdLife’s DataZone, the IUCN Red List, Cornell Lab’s eBird and Birds of the World will all be directly compatible.
Marshall Iliff, an AviList team member and eBird project leader at the Cornell Lab, said: “In trying to protect birds at a global scale, it is important to ensure that everyone is talking the same language and the data match.”
The launch of AviList has been described as a huge milestone in the world of avian science. The new checklist is published freely at https://www.avilist.org/. and can be downloaded in full for free. It can be downloaded in full or as a “short version” containing just the most essential fields, in both .xlsx and .csv. formats.