Yellow-billed Egret Ardea brachyrhyncha and Plumed Egret A. plumifera are split from Medium (formerly Intermediate) Egret A. intermedia (Clements 2007:20)
The mid-sized white egrets distributed in Africa, Asia, and Australia are readily identified on their breeding grounds and are now recognized as different species. Their non-breeding ranges are not entirely known and vagrant individuals may pose identification challenges.
Clements, J. F., P. C. Rasmussen, T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, A. Spencer, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2023. The eBird/Clements checklist of Birds of the World: v2023. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ (Link)
Unintended disagreements occur when a parent (B) is
thinned by swapping a child (E) to another part of the
taxonomic tree, resulting in existing IDs of the parent being interpreted
as disagreements with existing IDs of the swapped child.
Identification
ID 2 of taxon E will be an unintended disagreement with ID 1 of taxon B after the taxon swap
If thinning a parent results in more than 10 unintended disagreements, you
should split the parent after swapping the child to replace existing IDs
of the parent (B) with IDs that don't disagree.