(From San Vito Bird Club Taxonomy Tsar, Jo Davidson)

Not even a global pandemic can keep the Taxonomists of the American Ornithology Society from their appointed duties. Right on schedule, as always, they have announced the classification changes for this year. I’ll start with the three birds that have changes to both their English and scientific names.
Let’s begin with one of my local favorites. The Rufous-capped Warbler has been split into two separate species:

Rufous-capped Warbler (Basileuterus rufifrons)
Chestnut-capped Warbler (Basileuterus delattrii)

The easiest way to differentiate the two is that the Chestnut-capped Warbler has an entirely yellow
belly, and in the Rufous-capped, the lower portion of the belly is grey. There are other small differences, but they are very difficult to distinguish in the field. All the pictures I have taken in Coto Brus are of what is now called the Chestnut-capped, so I am guessing that one is more abundant in our usual birding spots.

Next on the list is the Tropical Gnatcatcher, which has also been split:
White-browed Gnatcatcher (Polioptila bilineata)
Tropical Gnatcatcher (Polioptila plumbea)

The Costa Rican species is now called White-browed Gnatcatcher. The species retaining the Tropical Gnatcatcher name resides in South America.

There is also a split of the Sedge Wren:

Grass Wren (Cistothorus platensis)
Sedge Wren (Cistothorus stellaris)

The Costa Rica resident species, which has an astonishingly small range in the Cartago area, is now called the Grass Wren. Note that the scientific name has not changed. The other species, which kept the English name but was assigned a new scientific name, is found in the U.S. and Canada.

Finally, here are the birds which have had changes to their scientific names only:
Neotropic Cormorant (Phalacrocorax brasilianum) is now Nannopterum brasilianum
Crested Caracara (Caracara cheriway) is now Caracara plancus
Striped Owl (Pseudoscops clamator) is now Asio clamator
Elegant Euphonia (Euphonia elegantissima) is now Chlorophonia elegantissima
Magenta-throated Woodstar  (Calliphlox bryantae) is now Philodice bryantae

Until next year, Happy Birding!