How to Know the Birds: No. 80, Rare Birds in Deep Time

by Ted Floyd

  • What: Northern Mockingbird, Mimus polyglottos
  • When: Monday, December 11, 2023
  • Where: Hazelwood, Allegheny County, Pennsylvania

Rarity is relative. Last month, on a visit to my natal city of Pittsburgh, Pennsylvania, I gave thought to that truth as I watched birds coming to a feeder at a local park: a radiant northern cardinal, a couple of Carolina wrens, and a trio of tufted titmouses. Standard feeder-fare in Pittsburgh, but those would be rarities around my home at the base of the foothills of the Rockies in Colorado: The wren and cardinal aren’t even reliably annual where I live, and the titmouse has never been credibly reported anywhere in the state.

Rarity has a temporal dimension, too. Anybody who’s ever begun work on a year list—let me guess, that’s more than a handful of the folks reading this right now—will know what I mean. The grackle or phoebe or catbird that barely elicits a glance in summer is a decidedly unexpected January addition to your year list. Depending on where in the ABA Area you’re based, such birds are full-on rarities in the dead of winter.

I said a moment ago that rarity has a temporal dimension, but I was imprecise. It has two temporal dimensions. In addition to seasonal rarity (rare in winter, common in summer), there is often a long-term dimension to rarity. The bird that is common in, say, 2024, might have been quite rare in 1984. Or vice versa. Anybody who’s ever uploaded old eBird checklists knows what I’m talking about: The evening grosbeaks and common gallinules I’ve entered for the early 1980s are flagged as rarities, but that’s relative to eBird filters intended for use in the 2020s. Those birds weren’t rare (the grosbeak in northcentral Virginia, the gallinule in Philadelphia) in the 1980s.

There were cardinals and Carolina wrens and tufted titmouses at that feeding station in the park, just as there were when I birded there regularly in the early 1980s. But there was also a red-bellied woodpecker. In Feb. 1983, I found a single individual of that species, an adult female, in the park, and I was thrilled. Day after day, I trekked to the park, typically after school and sometimes in quite inclement weather, to confirm that this local rarity was still there. There was also a Carolina chickadee at the feeding station when I was there last month; in the early 1980s, birders in Pittsburgh were just starting to appreciate that the species was beginning to establish in the city’s East End. It gets better: A common raven was up the hill from the feeding station. That species would have been a mega in the city in the 1980s. And even crazier, a fish crow flying over, calling diagnostically as it went on its way. That species was completely unrecorded from the entire region at the time, but it is common today.

My rather pedestrian list for that humid, overcast Dec. 11, 2023, would have been one of the grandest birding days of the year, anywhere in the region, 40 years prior. (And if I had lingered longer, I suspect I would have found other species, once rare but that are today routine in the park and environs in winter: pileated woodpecker, wild turkey, merlin, and others.) Objectively, in my head, I get that 40 years is a long time in the course of avian population dynamics. Change is to be expected. At another level, though, I can’t help but be affected by the many differences. When I go back to that old park, with the same old trees and trails, the same hills and ravines, even the same old birding friends from 40 years ago, I take a ride in a time machine. It is become 1983 again. I see a red-bellied woodpecker or hear a fish crow, and the birds are, in their way, heartstoppingly rare for me.

My ride back to the Pittsburgh airport was a birding friend from my childhood. He and I had met almost exactly 40 years earlier, on the occasion of the Pittsburgh Christmas Bird Count (CBC) in 1983. We took the long route, via an industrial park in the floodplain of one of Pittsburgh’s rivers, and we stopped to look at this:

Photo by © Ted Floyd.

Except for one little detail, that photo absolutely could have been from the 1983 CBC. The gray skies, the weeds in the foreground, the steep bluff rising off the river, and those old homes atop the hill. But what of the bird?

Photo by © Ted Floyd.

It’s a northern mockingbird, of course, common in the city at the present time. But it would have been a decidedly good bird for our CBC sector 40 years earlier. At the CBC compilation, there would have been reverent gasps in the audience when we solemnly spoke aloud the bird’s name.

Birding is situational. Somewhere in this land, cardinals and Carolina wrens are rarities. At some point in the year, catbirds and grackles are write-up birds. And at some point in our lives, a mockingbird is notable—and, if you’ll allow it, an antidote for nostalgia.

Because, without that mocker, our roadside stop would have been a mere reenactment, a waltz down memory lane, precious, and nothing more. But the bird changed everything: Yes, I was, in some sense, standing there in the early 1980s, but the mockingbird was a thrill, a time-traveler, an actual mockingbird, can you believe it?—right there, in real life, in a powerfully motive way, a rarity.

—Tuesday, January 23, 2024

Once-rare birds hold a special place in our hearts. Even long after they have become routine, we delight in encounters with them. This northern mockingbird, decades ago a local rarity, wonderfully transformed an otherwise dreary December afternoon. Photo by © Ted Floyd.



Ted Floyd is the longtime Editor of Birding magazine, and he is broadly involved in other programs and initiatives with the ABA. Ted has written 200+ magazine articles and 5 books, including How to Know the Birds (National Geographic, 2019). He is a frequent speaker at birding festivals and has served on several nonprofit boards. Join Ted here for his semimonthly spot, “How to Know the Birds,” celebrating common birds and the uncommonly interesting things they do.