Barr Lake, Adams County, July 2

[Ted Floyd]

Hello, Birders.

I had an errand yesterday, Wednesday, July 2, at Barr Lake, Adams County. Convenient place for a birder to have an errand, eh?

The very first bird I saw was a Cackling Goose. Photo here: http://tinyurl.com/Cackling-Barr-Lake Cathy Sheeter tells me there have a few here this summer. To which I say: What's up with that?

The only nuthatch I saw and heard was a good match for Rocky Mountain Nuthatch. And what, pray tell, is a Rocky Mountain Nuthatch? Well, Colorado's own peripatetic Steve Mlodinow has a handy primer in this month's Birding magazine, published by the American Birding Association, on how to separate the Carolina, Rocky Mountain, and Slender-billed nuthatches, two taxa of which occur regularly in Colorado. Here is a link to a PDF download of Steve's article:

http://aba.org/birding/2014-MAY-JUN/14-3_08Mlodinow-R4.pdf

All four of the vireos I saw and heard were good phenotypic matches for Eastern Warbling-Vireo. Here's audio of a Rocky Mountain Nuthatch with a descant from an Eastern Warbling-Vireo:

https://soundcloud.com/ted-floyd/wbnu-ls101522

Barr Lake is a great venue for appreciating the East-meets-West aspect of Colorado birding.

Complete eBird checklist here: http://ebird.org/ebird/view/checklist?subID=S18972990

Ted Floyd

Lafayette, Boulder County, Colorado

[Deborah Carstensen]

Ted, you were asking what was up with the cackling geese hanging out here for the summer.

I have up to 800 geese on the townhouse property where I live near Littleton in the winter time, many of them being the lesser forms.  By migration time, March or so, all of those geese leave with just the 50
Resident Giesting.

For the first time in the 11 years that  I've been here, a pair of lesser Canada geese and a greater white fronted goose stayed here. I was surprised by that. They didn't have any offspring, but did seem to be accepted by the other geese.

Deb Carstensen, Littleton, Arapahoe County, Colorado.
Sent from my iPhone

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[Ted Floyd]

Hello, Birders.

I appear to have erred in my assessment of the warbling-vireos at Barr Lake, Adams County, July 2. Which is cool, for two reasons. First, it is good to make mistakes and to recognize them as such; that's how knowledge, learning, and wisdom are attained. Second, the situation, as I now understand it, at Barr Lake is more interesting than previously reported.

The rest of the story:

So, I went back and actually listened to the audio and looked at the spectrograms.

First, here is a Barr Lake warbling-vireo singing a song that I consider to be a good match for Eastern Warbling-Vireo:

http://www.xeno-canto.org/184975

But here now is a Barr Lake warbling-vireo singing a song that I consider to be a good match for Western Warbling-Vireo:

http://www.xeno-canto.org/184977

The birds were within 750 meters of each other, i.e., within 1/2 mile of each other.

It's interesting that these occurrences are consistent with observations from Tony Leukering several years ago. Tony tells me that he detected an Eastern Warbling-Vireo in precisely the same location as "my" Eastern Warbling-Vireo from July 2nd--by the wooden footbridge at the main entrance to the park. Steve Mlodinow also has detected both Eastern and Western warbling-vireos in this area.

If I told you, I'd have to kill you, but...there there are murmurings about splitting the Warbling Vireo into two species of warbling-vireos. Observations from places like Barr Lake, where the two taxa appear to co-occur, are of particular relevance to understanding species limits in the Warbling Vireo, or warbling-vireo, complex.

DNA is needed.

Ted Floyd

Lafayette, Boulder County, Colorado

[jjedwa...@gmail.com]

Hello. I will be at Sands Dune National Park in a few days, a new area for me. I am especially interested in owls. Any specifics on owls and sites would be appreciated. Thank you for your cooperation.
Julie Edwards
Cynthiana, KY