Clements 2025 Is Here — and the Road to AviList
We’re pleased to say that the Clements taxonomy in Bird Journal is now right up to date with the latest 2025 release. It’s live in the library today, so you can bring your records into line with the newest checklist whenever you’re ready.
Getting the update
As always, you’ll see a number badge on the Library button when there are updates waiting to install. Most changes apply automatically, but some — species splits and lumps in particular — are ones you’ll want to look over yourself. Head to Tools ▸ Taxonomic Updates to see exactly what’s changed and to work through anything that needs a decision, and our guide on taxonomy updates walks you through the process if you’d like a hand.
Checklists have been updated to match, so the lists you record against stay consistent with the taxonomy behind them.
Why this release matters more than most
We’ll be honest: it has been too long since the last Clements update in Bird Journal — the previous one brought in the 2019 release, and a great deal has changed in the taxonomy since. Closing that gap matters in its own right, but this update is a little different besides. It’s a meaningful step on a bigger journey: the move towards AviList, the new unified global standard for bird taxonomy.
For years, birders have had to live with several competing world checklists — Clements, IOC and others — each with its own decisions about how species are split, lumped, named and ordered. AviList is the long-awaited effort to bring those worlds together into a single, agreed taxonomy. The latest Clements release moves firmly in that direction, and getting you onto it now means far less to reconcile when AviList itself arrives in Bird Journal.
In other words, this isn’t just housekeeping — it’s laying the groundwork so that the shift to a unified taxonomy is as smooth as we can possibly make it.
IOC 15.2 is next
We haven’t forgotten the IOC list either. IOC 15.2 is following shortly, bringing that taxonomy up to date alongside Clements. And we’re determined to do better from here on — to stay far closer to each new release than we have in the past.
Part of what gives us confidence there is the way AviList is built. As well as unifying the various world checklists, it’s designed to be much easier to keep up with: each species carries a stable identifier that stays put even as names change and species are split or lumped around it. That lets us see precisely what’s changed from one release to the next and apply it cleanly, rather than reconstructing it by hand. So aligning on AviList doesn’t just tidy up the taxonomy — it should make staying current far easier for us, and by extension more dependable for you.
AviList therefore remains firmly on our roadmap: we’ll be adding full support for it and making sure it’s genuinely easy to move over when the time comes.
Thank you
None of this happens without the painstaking work of the taxonomic teams at Cornell, the IOC and the AviList project, and we’re grateful for it. Thank you, too, for your continued support — do let us know how you get on with the update, and stay tuned for IOC 15.2.