Many birds at Greenlee Preserve, Boulder County, Sept. 6th

[Ted Floyd]

Hello, Birders.

It was a great day today, Sat., Sept. 6, at Greenlee Preserve, Boulder County. I saw two life birds for the site: Cassin's Kingbird and Loggerhead Shrike. Also a Townsend's Warbler and a Northern Waterthrush. And a stupefying amount of Wilson's Warblers. Also noted were Dusky Flycatcher, Plumbeous Vireo, Blue-gray Gnatcatcher, and Clay-colored and Brewer's sparrows.

The rest of the story:

The weather was wild. When I started, right around 4am, skies were clear, the winds were calm, and Uranus cast its soft blue-green glow on the rooftops and treetops. Well, not quite, but, seriously, Uranus is high in the sky now and easily seen as it wends its way through Pisces. And calling by migrants was very light: just one or two Chipping Sparrows, Wilson's Warblers, and Vesper Sparrows.

Around 5am, so just barely the start of astronomical dawn, calling picked up quite a bit--as if the birds knew something was coming?

Just before 6am, dew point was achieved. Being there for dew point is spellbinding; I've knowingly experienced dew point only a few times in my life. It's awesome to stand there and watch as everything suddenly sparkles in the dawn's early light. I have to say, I had no idea there were so many spider webs in Colorado!

Then a steady west wind kicked in, then an impressively dense fog, and then a low cloud ceiling that wouldn't blow out till mid-day.

The Wilson's Warbler fallout was amazing. Just after sunrise, every tree in the preserve seemed to have about half a dozen. My 1x1 count for the day was 94, and I suspect there were many more. Other warblers during the day included 7 Orange-crowns, 4 MacGillivray's, 1 yellowthroat, 6 Yellows, and the aforementioned Townsend's and Northern Waterthrush. Also, I wonder if I saw a Hooded Warbler; I only glimpsed a warbler, yellow below, that fanned its tail and showed nice white outer rectrices. What else could it have been? But I just couldn't get on it for a definitive look.

Sparrows were okay, with 1 Green-tailed Towhee, 2 Clay-colors, a Brewer's, and 10 Chipping.

As to the Cassin's Kingbird, it was hanging out in a dead tree on the northwest corner of Waneka Lake (so near the southwest corner of Greenlee Preserve). The Cassin's was conveniently near a Western Kingbird, and it obligingly called a few times. The shrike--a juvenile, I believe--was off to the east of the reserve proper, in a row of Russian olives along the edge of the organic farm ("Thomas Open Space").

By early afternoon, it was sunny and warm, with a nice showing by raptors (Turkey Vulture, Osprey, Cooper's, Swainson's, Red-tail), sundry water birds (including 10 Wood Ducks and 131 Blue-winged Teal), Broad-tailed and Rufous hummingbirds, a Solitary Sandpiper making a go-figure beeline straight north, and some latish Chimney Swifts amid the many still-lingering Barn Swallows.

Other odds and ends out there today: 13 wood-pewees, all of which seemed reasonable for Western; 2 Dusky Flycatchers; 1 Plumbeous and 2 Warbling vireos; 3 White-breasted Nuthatches, one of which wasn't necessarily the expected nelsoni ("Rocky Mountain") subspecies; 1 Blue-gray Gnatcatcher; 2 Cedar Waxwings; 2 Lazuli Buntings and a Lazigo spuh; and 2 Lesser Goldfinches.

eBird checklist here:

http://ebird.org/ebird/view/checklist?subID=S19756453

Ted Floyd

Lafayette, Boulder County, Colorado