You remember how the Yellow Warbler used to sing ‘sweet-sweet-sweet-I’m so sweet!’ near my balcony every dawn? And then he disappeared for a couple weeks. When I next detected Yellow Warblers from the balcony, they were actively flying about and chipping, but not singing. After consulting Birds of the World, I have concluded that these more recent individuals are ‘fall’ migrants, pretty much the earliest of the passerines, give or take a few Louisiana Waterthrushes and perhaps some Black-and-white Warblers. They don’t mess around: “Fall flight at a w. Pennsylvania banding station shows [a] very early peak of mid-Jul, with stragglers regularly through Aug and into Sep.”
I hope the local pair bred successfully. I find this fascinating:
Yellow Warbler frequently responds to cowbird parasitism by building over the parasitized clutch making multi-tiered nests…One…nest with 6 tiers contained 11 cowbird eggs, distributed as follows: 1 cowbird egg within original base of nest (laid during nest construction), 3 cowbird eggs in first tier, 1 in second tier, 2 in third tier, 2 in fourth tier, 1 cowbird plus 1 warbler in fifth tier and 1 cowbird in top; nest was 14.6 cm tall. (Peck, G. K., and R. D. James [1987]. Breeding Birds of Ontario: Nidiology and Distribution. Volume 2: Passerines. Miscellaneous Publications of the Royal Ontario Museum, Toronto, ON, Canada; cited in Birds of the World)
Another species on the move is the Short-billed Dowitcher. After recording the first-ever SBDO for the hotspot on Jul 1, the nocturnal microphone picked up a small flock at 11:09 PM on Jul 8th. These birds were migrating to the Atlantic Coast from their breeding grounds around Hudson Bay, where they “[nest] in wet meadows at treeline, dominated by sedge, cotton grass, small willows; also in muskegs within coniferous forest.”
Other shorebirds are on the move as well, but so far I’ve only recorded the occasional Spotted Sandpiper. Meanwhile, a smattering of zeeps could be from Yellow Warblers or other warbler species engaging in long-distance movement southward, or molt-migration.
Speaking of molt-migration, two species that do this—Wood Thrush and Veery—are both on the move in ever-larger numbers, though their calls only constitute a handful of NFCs per night. More surprising, the microphone picked up a Swainson’s Thrush at 2:06 AM on July 11th, by far the earliest record for this species here. Joe Gyekis’ NFC station in nearby State College has also picked up the species this July. I wonder if these are molt-migrants from Pennsylvania populations scattered through the mountains of our Northern Tier counties. The nearest know nesters are only about 40 miles north of Plummer’s Hollow.
Commensal Mensos
In less unusual news, three species that would nest inside our homes, if we let them, appear to be doing quite well this year, thank you very much. On Wednesday evening, I snapped a camera-shy Fernando the House Finch feeding the four-nestling third brood, who are beginning to vocalize their extreme need for regurgitated meals:
When we were up on the mountain for Mom’s birthday on Tuesday, I found out that four Eastern Phoebe pairs have been nesting simultaneously on the grounds: the Garage Phoebes, the Veranda Phoebes, the Spring House Phoebes, and the Shed Phoebes. Some are well into their second broods, and with little doubt they are the descendants of phoebes going back many generations (as long as I can remember, phoebes have been nesting here). It is tempting to spend a day just observing phoebes to find out how many are around. Elsewhere on the property, I am aware of a pair that nests on a hunting platform at the Far Field (I haven’t checked there this year) as well as at least three pairs, and probably more, along the Little Juniata River in the hotspot.
We mustn’t forget the Carolina Wren. Up on the mountain they nest in nooks and crannies of all the buildings, as well as in brushy patches in treefalls and field edges. Most recently, a pair has built a nest under the air conditioner that pokes out onto the veranda. As we debate whether it’s a real or a dummy nest, Paola approaches and a mother darts out into the lilac bush. Four eggs already!
Feeding Frenzy
On Wednesday morning, I sleep in and hit the balcony for coffee a bit late. It’s almost 6 AM by the time I settle down. The clear, dry cool-ish (59-degree) weather seems to agree with the local avifauna, which are more active and vocal than I would have expected. A Great Blue Heron flies high over the towers, heading north, around 6 AM, and another goes east not much later. Nine Mallard youngsters zoom in from the Gap and up over Bald Eagle Creek. Migrant Yellow Warblers are chipping about, while frenetic Cedar Waxwings and American Goldfinches are everywhere. As the caffeine really starts to kick in, I glimpse a light-colored, bulky shape flying low over the water through the confluence, but there’s too much vegetation to make it out clearly before it disappears downstream. In an abundance of caution—in case it’s not what it probably is—I don some shoes and sprint to the car.
My first stop in this mini-chase is the path down the river from the park-and-ride beyond the interstate. Nothing. Whatever it is, it kept going. I notice that the thick riparian brush seems packed with common birds quite agitated at my presence.
My next stop is the Plummer’s Hollow bridge. From here, there is an unobstructed view upstream to the same bend I can see downstream from the previous spot. No big surprise: a majestic (as always) Great Blue Heron pokes about the shallows a few hundred yards away. Nevertheless, it pays to be thorough. Unlike on Sunday evening, when I saw two adults and a juvenile together, the three I have seen this morning are all adults. Perhaps they are all different individuals, already moving about the region.
And then, as so often happens in birding, I hear something interesting and head off into terra nullius. One chip is from a Louisiana Waterthrush by the river, and the other a female American Redstart back in the woods. More calls are coming from up by the tracks. I’ve got a little time, so why not check it out?
I’m glad I do. All the action is taking place in various trees and bushes flanking the tracks on our side and the terra nullius side, just west of the crossing. Woodpeckers of the five common local species are calling and flying back and forth across the tracks, with Northern Flickers perching in tall snags. Ailanthus and others trees are dripping with Red-eyed Vireos in pairs and trios, while Ovenbirds and other local breeding warbler species, curious at my presence, flit out briefly into view before disappearing into the vegetation. Black-capped Chickadees are all about, never shy. Even a Cerulean Warbler is singing; this is one I rarely hear down here in the summer. Scarlet Tanagers, Rose-breasted Grosbeaks, Indigo Buntings, Acadian and Great Crested flycatchers: they’re all here, males, females, juveniles.
I believe this constitutes the first substantial mixed-feeding event I’ve seen this season. I hesitate to call it a ‘flock’ as I don’t think any of these are long-distance migrants going anywhere in particular, and I doubt they are moving together locally, either. Some are probably molt-migrants from not far away. Most seem to be here for a single purpose, as there are far more individuals and species than normal at this location.
The 34 species I eventually detect mostly seem to be converging on a single food resource that is concentrated and abundant. I don’t have a lot of time before work, but the most I can make out are Red-eyed Vireos smashing small, wormy-looking things against tree branches with their beaks. I would guess it is some sort of caterpillar, but don’t quote me on that.