In a word: everything.

Birders, of all people, should know how much language shapes experience. There’s a strong argument (and I think I’ve made it here and there over the years) that our hobby is exclusively verbal, that nothing we say or do in the field matters until we’ve actually uttered the name of the bird we’re watching.

But words don’t just capture experience; they also create expectation. And for birders, those expectations shift with each taxonomic revision.

I had plenty of time to think about such things this quiet morning at Mills Reservation. A female Common Yellowthroat lurking in the jewelweed and mugwort along the roadside was my first for the site, and occasion to ponder as I never had before whether it would be possible or not to mistake her for a Mourning Warbler–a thought that would probably not have occurred to me at all before the re-arrangement of the parulids in this past July’s AOU Supplement, which moved Mourning and MacGillivray’s (but not Connecticut) into the long-standing yellowthroat genus Geothlypis.

A few minutes later I was peering into the denser, darker understory of the woods proper, where a Veery and an apparent family of Wood Thrushes (two adults with a still fuzzy-headed young bird, all popping and plicking loudly) were sharing the windfall with Gray Catbirds, Blue Jays, Common Grackles, and a few American Robins. Now Veeries and Wood Thrushes don’t look much alike at all, but the question occurred to me whether I might not think otherwise if their genera (Catharus and Hylocichla, respectively) were (as they have been at times) once again synonymized as a broader Hylocichla (or Turdus, for that matter, as both were originally described). Wouldn’t the verbal suggestion of closer relationship make me focus more closely on the similarities than on what are, for now at least, the manifest differences between those two big-eyed brown birds of dark thickets?

Veery

Names, those most powerful of words, color our expectations–and our observations–more than we sometimes know.  Our mornings afield are mediated events, where we come into contact with the world not on its own terms but as it has been captured for us in language; we see similarity, we see difference, where words have prepared us to look for it.

Wood Thrush

Maybe I’m getting spoiled already, but Mills Reservation seemed a bit on the slow side yesterday morning, with just nine species of warblers, all of them (with the beautiful exception of American Redstarts) in small numbers. The weather was pretty dank, too, warmer than expected and much more humid than hoped.

So I came home and waited for the weather to get worse, which it obligingly did towards evening: more clouds, oppressive humidity, and just the slightest of sprinkles. But then, as I watched the sky and wondered how long it would be ’til we saw the sun again, a distant flicker of wings drew my attention. A Common Nighthawk–and another, and another, finally a total of nine that drifted in from the north to hunt over the neighborhood swamp.

For many of us, nighthawks are birds of childhood, observed and enjoyed long before we were “birders” and long, perhaps, before we even really knew what they were. I don’t recall when I first heard the name “nighthawk,” but I have clear and happy memories of watching these dramatic birds flitting over night-lit baseball fields, streaming south on autumn afternoons, flashing through the spotlights on the state capitol building. I haven’t seen many over the past few years, in part because the species is scarce in southern Arizona, in part because it has declined throughout its range–so you can bet that I’ll be out in the evening again once this hurricane passes and the skies are safe for nightjars.

It’s amazing how quickly and how severely one’s sense of scale shrinks east of the Mississippi. Vancouver to Manning Park for some mountain birding? No problem. Tucson to Imuris to check out the migration? Easy. Little Falls to Mills Reservation? Yikes, that’s in another county, it’s four miles from us!

But I girded my loins and filled the tank anyway, and arrived early enough this morning that the spiders were still unmolested.

The quiet didn’t last long, thanks to the horde of proudly scofflaw dog-owners (is there any place not similarly plagued?); but I didn’t much care, because there were birds to be seen.

As expected, activity was concentrated along the sunny edges, with the deeper woods left to the White-breasted Nuthatches and Tufted Titmouses. Around the parking lot, though, and atop the exposed ridge, there were clusters of parulids, and I wound up with my first 10-warbler day of the autumn. Even more exciting than the diversity was the relative abundance: I had multiple individuals of most of the species I saw, giving me a chance to look at different plumages and–a thing greatly to be desired–to try to get my ear back in with the eastern warblers’ chips.

I did all right relearning a few call notes, though more than once, I’m afraid, I misidentified as American Redstart the distant chirping of this fine creature.

Fortunately, there were enough genuine American Redstarts around to provide a check on my aural imaginings. In fact, that lovely bird was the commonest of the morning’s warblers, followed by Black-and-white and Canada. I suspect that some of the half dozen or more Ovenbirds were locals; at least they acted as if they owned the forest floor.

I also saw multiple Blue-winged, Blackburnian, Magnolia, and Chestnut-sided Warblers, all of them pretty exciting for a recent westerner. And two species, Black-throated Green and Prairie Warblers, were each represented by a lone individual.

There are lots more “greens” to come, but that Prairie was a mild surprise. This is probably the area of New Jersey where that species is rarest, and even where it is common, I don’t often see it in migration: it seems like many of the more southern warblers are like that, simply slipping away in August. I’m glad that this one didn’t.

The rain cleared out, leaving us northwest winds, blue skies, and mushrooms as big as my hand. A perfect morning for migrants!

Except nobody told the migrants. I spent a short while in our local swamp, sure that the trees would be dripping with warblers and the damp ground littered with thrushes. It was not to be. In 40 discouraging minutes I saw a grand total of 12 (!) species, not one of which we hadn’t enjoyed from the kitchen window over breakfast.

In spite of my overall disappointment, there were two birds of mild local note. A male House Finch was, surprisingly enough, the first of that species we’d had here in our three weeks, as was a small band of three or four Tufted Titmouses that moved through the yard, later to mob me in the “swamp.”

Neither of those species is generally thought of as migratory. And if we think of migration as the traditional south-in-the-fall-and-north-in-the-spring movement shown by so many of our birds, they aren’t. But both are certainly mobile.

The late summer withdrawal of House Finches from their urban nesting grounds is well known and striking over their eastern and midwestern range; I’ve long believed that the tendency to seek weedy, seedy habitats in August is one of the major elements in the species’ successful dispersal since the 1940s.

The movements of Tufted Titmouse are a bit more mysterious. Given the northward spread of that species over the past near-century, it’s obvious that this is not the strictly sedentary beast it’s generally considered. Walsh et al.’s Birds of New Jersey mentions an episode I would love to have seen: more than 700 titmouses over Overpeck Park in October 1995. Not far from here; I’ll have to keep an eye out and see if our morning wanderers turn out to be the start of something big.