Update and questions on Arvada Blunn Res grebes - Jeffco (fairly long)

[Chip Clouse]

Cobirders,

Photos obtained by others after my report of a Red-necked Grebe (RNGR) yesterday show birds too small and with too small of a bill to be RNGR.  These 2 birds were seen and photographed from fairly close to shore on the west side whereas my initial sighting was of 1 bird on the east side by the dam and spillway. Did I make an ID mistake or were there both juvenile Horned Grebes and a RNGR out there?  Not sure. It wouldn't be the first time I misidentified a bird.  And it reminds me that I should never leave home without my phone adapter and that I should try to digiscope more often, especially when rareties are involved.  

I definitely had an adult basic-plumaged Horned Grebe cavorting with American Coots at the same time but know my initial bird of excitement had a bright red neck and the presence of facial stripes indicative of juvenile grebes of several species. From numerous app pics and drawings, I thought a red neck in juvenal plumage had to be RNGR.

My question to those more learned concerns grebe molt. If rufous (or chestnut or red) necks occur in adult alternate-plumaged Horned Grebes (and we know they do), when does that molt occur? Spring, right?  Is it possible for an October Horned Grebe to have a red neck and retain juvenile facial markings? It also reminds me to pay closer attention to more than a couple field marks and not "assume" anything as I also saw the closer birds that were photographed but had stopped "looking" at them once I had put a name to them. Bad boy... Same thing happened on a tour to SoCal where I stopped "looking" at gnatcatchers to find other things. Once home, a participant showed me excellent pics of California Gnatcatchers among the Blue-gray Gnatcatchers I "assumed" they all were. Bad boy...

After seeing someone else's photograph of facially-striped Horned Grebes with some rufous in the neck from yesterday (that I don't own and can't post here), I'm wondering if the late afternoon sun duped me or if there is actually a bright red-necked RNGR out there.  Even at 40x through an alpha scope I would think it difficult to see a diminutive Horned Grebe well from so far away.

In short, I can't get back out there today and would appreciate comments or updates from anyone who can, especially if you find a RNGR! I may need to edit my checklist.

Humbly yours,

Chip Clouse 

Golden

[David Bailey]

To contribute to the discussion, here are two of the photos I was able to snag (and crop a bit) from the Blunn grebes yesterday with Chip:

David Bailey,

Golden

--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+u...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/CAPHVJehRzg51ZJ3-w%2BN2rJidCUCi2kpr6LN7oE3Mc3H6MknnpA%40mail.gmail.com.

[Chip Clouse]

Pied-billed juveniles. As I stated before I carelessly stopped "looking" as these are definitely different birds that the 1st bird I saw on the east side of the lake with a full red neck. My apologies to David and others for not staying on the 1st bird.

Chip Clouse

Golden