As the night wore on, storms began to flare up in Oklahoma. Here in Stillwater those storms hit between 1:30 and 2:00 am on Sep. 24. As the storms expand, migration stalls: Birds put down to avoid the storms and for people on the ground, that’s a fallout.
11:41 pm CDT, Sep. 23.
1:41 am CDT, Sep. 24.
3:41 am CDT, Sep. 24.
5:41 am CDT, Sep. 24
Was there evidence of this fallout on the ground?
Well, there was a bonus Canada Warbler in that troublesome northeastern alcove of the Food and Agricultural Products Center. (This was in addition to a Mourning Warbler and a Wilson’s Warbler I found there on Sep. 21.)
male Wilson’s Warbler, Sep. 21
female Mourning Warbler, Sep. 21
female Canada Warbler, Sep. 24
female Canada Warbler, Sep. 24
There was a big flight of Nashville Warbler in Stillwater, too. Twelve were reported from Couch Park. I found one in the southwestern alcove and a Ruby-throated Hummingbird in the northeastern alcove.
Yet another Mourning Warbler today. This one was in the southwestern alcove. I don’t know if it had been chasing this grasshopper and they both died at the window, but it sure did look unusual to find these two together.
As storms rolled through overnight, I assumed I might find a casualty this morning. There were two: a completely rain-soaked female Indigo Bunting in the southwestern alcove and a completely dry and fluffy Mourning Warbler at the south entrance under the rain protection provided by the portico’s overhanging roof. The latter was an AHY male with fat = 3.
This morning I found the fifth dead Mourning Warbler on campus in the past two weeks: Four (including this one on the northwest alcove) at the Noble Research Center and one incidental find just across a small parking lot from the NRC at the Food and Agricultural Products Center.
For a bit of perspective on how unusual this is, i.e., Mourning Warbler is a secretive, migratory transient in Central Oklahoma that is far more likely to be found dead at a window than live on an eBird checklist, this was the 15th Mourning Warbler casualty I’ve found at the NRC since I began surveys in August of 2009. In comparison, I’ve only found 17 casualties over the same time period of the far more abundant and year ’round resident Mourning Dove.
This one was a hatch-year bird – so just a month or two old – with fat = 1.
The wave of Mourning Warbler migration continues and the casualties mount. Here is an adult male from the southwestern alcove cut down in his prime with fat = 3 and trauma evident on the tip of the upper mandible.
Both Ag Hall and the Food and Agricultural Products Center, across Monroe St. from the Nobel Research Center – see their fair share of window collisions, too. Today, the latter building claimed this Mourning Warbler, the third I’ve found window-killed on this campus over the past week.
There was more mourning for me this morning, as I found a nearly identical bird to the casualty from Tuesday: Hatch-year Mourning Warbler; indeterminate sex; fat = 3. Here is another youngster on its first journey from the boreal forest to perhaps Colombia or Ecuador, cut down in perfect health from a stupid window in the southwest alcove.
I’m mourning the loss of another one today – this AHY female I found at the northwest alcove. She was fat (=3) and healthy at 12.5g.
This was the unofficial 315th casualty on the project and, for a new sobering record, the 44th this year. The previous annual high was 41. We’ve surpassed that already in 2017 and, for us, migration is really just ramping up.
There was a HY Chipping Sparrow in the northwest alcove. The bird had evidently been stepped on or perhaps run over by a maintenance vehicle. I left it in place for a removal trial.
Also, near the main north entrance (actually at a west-facing facade in the corner) was a Mourning Warbler. The bold eyering and long undertail coverts looked tantalyzingly like a Connecticut Warbler. It was, however, an AHY-U Mourning Warbler. The bird was 13.5g and bulging with fat (3).
This was the 10th Mourning Warbler on the project.
With apologies for the 1) poor and 2) non-existent photos . . .
I found an ASY male Mourning Warbler (fat = 0) at the main north entrance this morning. He was waaaaay better looking than these photos attest, and I bet he was even more handsome in life.
In the northwest alcove lay a female (with well-developed brood patch!) Yellow-billed Cuckoo (no photo). I left the cuckoo in place, as the ants were already doing a number on her.
In scavenging news, the starling from 5/18 was both moved and eaten: I found a remnant pile of its larger feathers about 5m away from the bird’s location. Whatever picked it up had taken it south to the bushes in front of the northern entrance.
I found our 8th Mourning Warbler of the study on Sep. 1, in the southwest alcove. It looked to be an ASY female, but I did not handle it for close examination. I left it for a scavenging trial.
The backstory for this bird is that it actually died yesterday sometime after my morning check and before Corey’s 11:30 am check. This was a broad daylight collision. I counted it here as a Sep. 1 fatality because I wouldn’t have discovered it until this morning had I been on my own. I would have noticed that the bird was not a fresh casualty, but the best I could have done was say that it died sometime yesterday after my morning search and probably before midnight. With Corey’s information, we now know that it was in place nearly 24 hrs before I detected it on my own.
On the heels of an unusually powerful cold front – with temps struggling to the 70s! today – the Noble Research Center claimed its first real fall migrant this morning, in a HY-U Mourning Warbler. This is the 7th Mourning Warbler on the project. This bird was young but it was in excellent shape and bulging with fat (scored a 3). (Apologies for the non-standard photography.)
Here’s last night’s flight on radar. Birds were on the move both ahead of and behind the storm.
Around 10:00 pm last night: Here’s the storm bearing down on us ~ 4:00 am:
Thanks to concurrent surveys between Corey Riding’s project and my own, I learned Monday (5/25) of a bird that I had missed on Sunday (5/24): At the north entrance and tucked under some shrubs is a Mourning Warbler. I missed the bird on two consecutive surveys. Corey thinks it must have come in sometime during the day on Saturday (5/23).
I’m not too upset to have missed this bird – twice! – because it is waterlogged and cryptic against the background mulch on which it lies and I could only see it from a specific angle that I rarely take when investigating that section of shrubbery. The key is not to never miss a bird on a survey, it’s to conduct redundant surveys to estimate how many I might be missing. Thankfully, that number seems to be quite low, but we’ll know better what it actually is in a few months.
Both Mourning Warbler and the Swainson’s Thrush were in place this morning.
I had two trapped birds at the Noble Research Center this morning, both of which presented identification challenges because they were in good enough shape that I never got to examine them closely. I first found what turned out to be a wood-pewee (and I’m assuming it’s Eastern) at the northeast alcove and then found a warbler I’ve identified as Mourning at the northwest alcove. I was able to steer both birds away from the building so I am hoping that I won’t find them dead there tomorrow morning.
Here’s the wood-pewee. When I first came upon it, it was sitting on the ground, its long, low shape and attenuated bill had me momentarily thinking it was a swallow. As I approached (within just a few feet) it was clear that I actually had a flycatcher, but it wasn’t until it flushed to perch on a nearby railing that I figured out that it wasn’t an Eastern Phoebe.
This bird was intermediate in size between a phoebe and and Empidonax flycatcher. It lacked the white throat of an Eastern Phoebe, it showed a bi-colored bill, and it did not wag its tail. Relative to Empidonax flycatchers, this bird was larger and lankier, with a long primary projection, little to no greenish cast on the upperparts, no obvious eyering, and a dusky grayish vest. All signs point to it being a wood-pewee, and I can only assume it’s Eastern as I wouldn’t be able to distinguish it from an extralimital Western in a photograph. The buffy wingbars suggest a hatch-year bird. This is the first wood-pewee on the project, and here’s where Easterns have been reported this month:
The Mourning Warbler on the northwest side of the Noble Research Center was also in good enough condition to fly off on its own, so I was left with my crude photographs to make the identification. At first blush, the olive-green upperparts, yellow breast and throat, and grayish head suggested Nashville Warbler. The structure didn’t fit well, however. The bill wasn’t narrow enough for Nashville, and the pale lower mandible didn’t fit either. The eye-ring seemed thin, and broken, unlike the bold, complete eyering on a Nashville. The feet were big and pale, as opposed to a Nashville’s small, blackish feet. The yellow throat pegged the bird as hatch-year, but I’m reluctant to call the sex.
No casualties at the Noble Research Center this morning, but I found this bonus Mourning Warbler on the south side of the Food and Ag Products Center.
This was a hatch year bird, and probably a female. She was in prime shape for migration, with fat = 2. No Mourning Warbler should end up stiff on a sidewalk in Oklahoma. Here’s where these birds are supposed to be in the first two days of September:
Today, the Painted Bunting remains in place but the Ruby-throated Hummingbird carcass is fully gone. It lasted approximately 5 days.
At the north entrance, I flushed a small, olive-green warbler with noticeably long and yellow undertail coverts. The bird bumped the glass near me, but I was able to steer it away from the building and into some ornamental trees. I was unsuccessful at relocating it after that. My best guess is that the bird is a Mourning Warbler, given size, coloration, and the long undertail coverts. The spatial distribution of collisions now looks like this: