CLOSED: nectar/insect eater, southern California

This bird was sucking aloe nectar out of this tree aloe, Los Angeles

Audubon's Warbler.

Recently re-split from Yellow-rumped Warbler-we're back to Audubon's (west) & Myrtle (east).

I think it's still ok to refer to both as Butter-Butts.

Just FYI for palmbob: North America's governing body for bird taxonomy voted against the split. In North America your bird is called a Yellow-rumped Warbler. The two mentioned by OldNed are currently recognized as subspecies. Saying "we're back" to the split is misleading since both questioner and answerer are from North America

Yep, flatpickit is correct.

In April, 2010, discussing his predictions re likely AOL Splits & Lumps, David Sibley opined the following:

“Yellow-rumped Warbler – Myrtle (Eastern) and Audubon’s (Western).

Two populations differ consistently in plumage and calls, slightly in song. These were lumped as a single species in the 1970s, but further research and a shift in philosophy now points to full species status. They certainly seem at least as distinct as Baltimore and Bullock’s Orioles.”

However, voting in June of 2012, the AOL did not split the genus:

'The taxonomy of these Yellow-rumped Warbler subspecies was under consideration for change by a committee in the American Ornithologist Union (AOU).

The vote was 7–4 against any divisions of the Yellow-rumped complex. The committee members suggested the need for further genetic analysis and determination of the extent of interbreeding in the subspecies’ contact zones where the “Myrtle” group (coronata), and the “Audubon’s” group (auduboni) mix in western Canada".

I noticed 'my' yellow rummer has a yellow neck, but I do not see this color on any of the other photos in the bird files... seasonal color change? Male?

If you're looking at Myrtle Warbler subspecies pictures in the Bird Files, the throat will be white.

Your western US subspecies, Audubon's Warbler, has a yellow throat.

Yep, seems the AOU are being a bit reactionary and out-of-touch with the rest of the world, which has accepted they are two separate species.

Resin