My reflection in a Christmas ornament at Phipps Conservatory, 16 Dec 2025 (photo by Kate St. John)
20 December 2025
After Sunday’s 6″ of snow, the snow melted midweek (Wednesday’s high up to 60°F), a windy cold front arrived on Friday, and this morning it was 15°F at dawn. In the meantime I found reflections, animal tracks, and an unusual song sparrow.
Reflections: My own reflection in a Christmas ornament, plus the first hint of Thursday’s spectacular sunrise in a reflection outside my window.
Red sunrise reflected on an apartment building’s windows, Pittsburgh, 18 Dec 2025 (photo by Kate St. John)
Here’s the sunrise that made that reflection.
Sunrise in Pittsburgh, 18 Dec 2025 (photo by Kate St. John)
Tracks in the Snow, 17 December: What are these tracks below the bird feeders at Frick Park? Every set is an arc of four splats (two paws per splat), and the animal seems to wander.
Virginia opossum tracks near feeders at Frick Park, 17 Dec 2025 (photo by Kate St. John)
A closer look at the opossum tracks at Frick, 17 Dec 2025 (photos by Kate St. John)
A Collared Nape: [“Nape” is the back of the bird’s neck.]
On Tuesday I encountered a song sparrow who was not afraid to get close so I decided to photograph him with my cellphone. That’s when I realized his white collar is not snow stuck to feathers. It is actually leucistic feathers on his nape. Here he is from different angles.
Song sparrow forages near me at Schenley Park, 16 Dec 2025 (photo by Kate St. John)Song sparrow with leucistic feathers on its nape, 16 Dec 2025 (photo by Kate St. John)Song sparrow with leucistic feathers on its nape, 16 Dec 2025 (photo by Kate St. John)
A long term study of dark-eyed juncos at UCLA campus has discovered that the beak sizes of campus juncos changed in just one year in response to the COVID shutdown and changed back again after the shutdown ended. Researchers concluded that human presence and absence made the difference. Authors Diamant and Yeh wrote:
The COVID-19 pandemic provided a natural experiment to test the impacts of human activity on urban-dwelling wildlife. Urban dark-eyed juncos differ in bill shape and size in Los Angeles in comparison to local wildlands. We measured juncos that hatched before, during, and after COVID-19 restrictions at a Los Angeles college campus [UCLA]. Birds that hatched during and soon after COVID-19 restrictions had bills that resembled those of local wildland birds. Yet, bills rapidly returned to pre-COVID-19 morphology in birds hatched in the years following pandemic restrictions. Thus, human activity (and lack thereof) underlies rapid morphological change in an urban bird.
Ever since the study began in 2017, researchers have known that UCLA juncos have shorter and less deep bills than those in wild areas. The bird at top, whose beak is long and conical, was photographed in the Los Angeles National Forest. The banded bird below at UCLA has food in his beak. However it’s possible to see his beak is smaller and less conical. (photo taken at UCLA by Alexander Yan)
During the COVID lockdown (the anthropause) human activity dropped around the world though it varied by jurisdiction. In California the lockdown ran from March 2020 to June 2021. There was very little human food waste at UCLA during that time.
Juncos that hatched in 2020 were conceived before the shutdown when their parents had access to plentiful food waste; these had typical small beaks. When UCLA’s adult juncos experienced the anthropause, young that hatched in 2021 and 2022 had large wild-lands beaks. And now, ever since the shutdown ended, UCLA junco chicks again have small beaks. (photo taken in 2025 at UCLA by Alex Fu)
Two graphs from the Open Access study show how rapidly hatch-year beak sizes changed. (Note that the beak size stays with the bird its entire life.)
On Sunday at Duck Hollow we found hundreds of American robins loudly feasting on fruit in the ornamental trees and honeysuckle bushes. Flocks of 50 or more flew overhead heading south. Though I knew a snowstorm was coming in 36 hours I had not internalized it but the robins had. They were frantic to eat and run … or rather … fly south to avoid the storm.
The American robin (Turdus migratorius) flocks that visit Pittsburgh in November are on their way south, but slowly. They stay as long as there’s abundant fruit and the ground is not frozen or covered in snow. As soon as any of those conditions are met, they’re gone.
This time their departure was particularly abrupt. So many robins on Sunday, so few on Tuesday. No robins here among the snow.
Snow-covered tree on Pitt’s campus near Heinz Chapel, 2 Dec 2025 (photo by Kate St. John)
Watch American robins’ week-to-week movements throughout the year in this eBird Status and Trends animation. Notice how they breed in Alaska and Canada and abandon them in winter. They are among the big flocks see in Pittsburgh in the non-breeding season.
And though we see a lot of robins in late fall and early spring, they are sadly declining in spring and summer. If you live in a Midwestern state (Ohio, Indiana, Illinois, northern Kentucky, Michigan, Wisconsin) or in the I-95 corridor from Massachusetts to DC, American robins are trending sharply downward during the breeding season. In the decade from 2012 to 2022 losses were -10% to -14.8%.
Now that it’s cold we’re all wearing winter coats.
We humans make decisions every day about what layers to put on, but birds and animals changed into their winter coats a couple of months ago.
White-tailed deer have two different coats of hair during the year. The gray winter coat is comprised of longer guard hairs and a soft wooly underfur that provide insulation from the cold. This thicker winter coat is shed prior to the hot summer months. The shorter summer coat is reddish-brown and lacks the thick insulating underfur. The summer coat hairs are short and wiry.
Non-migratory birds molt into fresh new feathers with added insulation in late summer. House sparrows (Passer domesticus) increase their plumage weight by 70% between August and September. Their typical summer plumage weight is 0.9 grams, winter weight is 1.5 grams, but they won’t look heavier until it’s really cold.
Habitat is everything. We tend to forget this because humans are versatile and avoid places where we cannot survive (Antarctica). Many species, though, require a specific habitat for their livelihood. When it becomes scarce, they have nowhere to live and may go extinct.
Less than 200 years ago grasslands dominated much of the continental U.S. where fires and less rainfall kept them open. Since then most grasslands have been converted to farmland, cattle ranges, or suburbs and now more than half of what remains is at risk of range-wide collapse. Relict grasslands support the last remaining species. The relicts themselves would disappear were it not for prescribed fire.
On Wednesday November 19, 7:00pm – 8:30pm, Phipps Conservatory is hosting a screening of the new nature documentary The Little Brown Bird, which tells the story of the Florida grasshopper sparrow, one of the most endangered birds in North America. A few years ago, there were as few as 50 Florida grasshopper sparrows remaining – today, there are as many as 200.
The 30-minute film focuses on the work of wildlife biologist Fabiola ‘Fabby’ Baeza-Tarin and a coalition of conservation partners who are working to rescue this sparrow back from the brink. The film’s director and cinematographer, KT Bryden, will join attendees virtually for a discussion after the film, and a panel of local speakers—including Ryan Miller, a wildlife biologist with the Western Pennsylvania Conservancy; Julie Travaglini, the director of education for the Allegheny Land Trust; and myself, Andrew Moore, a nature writer and author.
In addition to the Florida grasshopper sparrow the panel discussion will touch on the plight of grasslands and the endangered species they host, such as the massasauga rattlesnake in Pennsylvania.
Join Phipps for a screening and discussion of The Little Brown Bird. Price is $15 for members, $20 for non-members. Click here for tickets.
p.s. There are 12 subspecies of grasshopper sparrows. We see Ammodramus savannarum pratensis in Pennsylvania as it breeds in the eastern U.S. and southeastern Canada. The Florida grasshopper sparrow is non-migratory and only occurs in a small part of Central Florida.
See the beautiful rosy male and olive-yellow female in the highlights video below. Listen carefully and you’ll hear their contact calls, a single clear whistle. You’ll also hear crows and ravens in the background.
“This streaming cam is located in a residential neighborhood in Manitouwadge, Ontario, Canada, a small town 430 miles northeast of Duluth, Minnesota, and is hosted by Tammie and Ben Haché who have been members of Project FeederWatch since 2002. Their backyard has a large birch tree, a mixed stand of conifers and several fruit and berry producing shrubs. Just beyond the backyard there’s a small swamp as well as larger stands of woods and a small lake. It’s an excellent location to see winter finches, like redpolls and grosbeaks, as well as two species of Jays and even Ruffed Grouse.” — Paraphrased from Cornell Lab Bird Cams
Do pine grosbeaks come to southwestern Pennsylvania? No. These bulky finches eat mountain ash berries (Sorbus americana) in winter and won’t leave home unless the fruit is scarce. Even then, they only wander to areas with lots of mountain-ash berries.
Southwestern Pennsylvania has a few of mountain-ash trees planted as landscaping but these trees do not occur here naturally. The last time pine grosbeaks came to southwestern Pennsylvania was in 1973.
If you want to see pine grosbeaks, watch the Ontario Feedercam at http://allaboutbirds.org/feederwatchcam This link also has highlight reels and information about the birds.
Burr oak acorns, Flagstaff Hill, Schenley Park, 17 September 2025 (photo by Kate St. John)
20 September 2025
There are so many oaks in Schenley Park that a few burr oaks (Quercus macrocarpa) are not noticeable until they drop their large, fringed acorns. Where did they come from? I looked up to find the tree, taller and broader than its neighbors.
Burr oak acorn, Flagstaff Hill, Schenley Park, 17 September 2025 (photo by Kate St. John)
The burr oak’s location does not have a good view so I sat beneath a large oak at the top of Flagstaff Hill overlooking Oakland. Based on acorns, leaves, and the history of landscaping in Schenley Park, my guess is that I sat beneath an English oak (Quercus robur).
(presumably) English oak acorns, Flagstaff Hill, Schenley Park, 17 September 2025 (photo by Kate St. John)
It’s a high mast year for this particular tree. The only way I avoided being hit by acorns was to sit with my back against the trunk!
Other sightings this week include birds Tuesday morning at Bird Lab’s Hays Woods banding which I wrote about on Wednesday’s blog: Hays Woods Birds Live up to Expectations.
Common yellowthroat at Hays Woods Bird Lab, 16 September 2025 (photo by Kate St. John)Dotted line across the morning sky, Pittsburgh 17 Sept 2025 (photo by Kate St. John)
I rarely walk through the Heinz Chapel Memorial Garden but its fountain is attractive during the drought. On the way to the fountain I found an engraved paver stone with a non-traditional dedication.
Memorialized paver stone at Heinz Chapel, Univ of Pittsburgh, 17 Sept 2025 (photo by Kate St. John)
If you want to find this stone, enter the Heinz Memorial Chapel Garden from the Bellefield Avenue side (near the steps to Bellefield Ave) and look at the pavers along the left. (This photo does not include a view of the Will You Marry Me paver.)
Interestingly, BirdCast predicted that the night before would have Low Migration yet the number and variety of birds banded early yesterday was high. Nick says they have never been able to correlate busy banding days with bird forecast predictions.
Best Bird yesterday was an adult female mourning warbler, pictured at top. My photo isn’t very good so I’m including one from Nick Liadis @bird_lab on Instagram.
Other beauties included American redstarts … (I got to release one of them!)
Female American redstart, 16 Sept 2025, Bird Lab at Hays Woods (photo by Kate St. John)
… a very cooperative white-eyed vireo …
White-eyed vireo, 16 Sept 2025, Bird Lab at Hays Woods (photo by Kate St. John)
… an ovenbird …
Ovenbird, 16 Sept 2025, Bird Lab at Hays Woods (photo by Kate St. John)
… and a common, somewhat secretive warbler in an uncommon pose. Very yellow!
Common yellowthroat, 16 Sept 2025, Bird Lab at Hays Woods (photo by Kate St. John)
When he turns his head it’s easy to see he’s a common yellowthroat.
Common yellowthroat, 16 Sept 2025, Bird Lab at Hays Woods (photo by Kate St. John)
I was so excited about the birds yesterday that I forgot to take a photo of the banding operation so here’s a three year old photo. The operation is essentially the same, but now Nick has 14 mist nets and Shaina, Dana and Kathleen to help.
Nick Liadis and Lisa Kaufman, bird banding at Hays Woods, 7 Sept 2022 (photo by Kate St. John)
Learn more about Bird Lab or schedule a visit to a banding site at birdlab.org.
The breeding season is over for brown-headed cowbirds in Pittsburgh. The adults courted constantly while the females were fertile but egg-laying stopped in mid-July. By now all the youngsters have fledged and left their hosts to join flocks of cowbirds. These youngsters were raised by another species so how do they know what flocks to join? A new study found out their parents have nothing to do with it.
If the biological parents don’t care for it, why doesn’t the young cowbird stay with its host species?
Unlike most birds, a young brood parasite doesn’t get attached to its host parents. You can see this if you rear cowbirds by hand, said Mark Hauber, a comparative psychologist at CUNY Graduate Center in New York: “They start hating you at some point.” If a cowbird imprinted on a family of yellow warblers, say, and sought out warblers’ company as an adult, it would never find a mate and reproduce.
Early studies on how the youngsters discover their own species found that young cowbirds are attracted to the chattering calls of adult females, prefer to associate with birds whose plumage matches their own (immatures and females look similar), and many even hang out with their mothers.
However, the new study published in ScienceDirect in August conducted DNA tests on groups of immature cowbirds and adults captured together and found that the youngsters always hung out with females but they were never related to them.
Somehow, Chamberlain says, they bump into adult cowbirds and start hanging around them and learning how to behave. But the clock is ticking: By the end of the summer, the juveniles and adults will migrate south.“They have a short time period in which they need to learn these things,” Mr. Chamberlain said.”
Though eastern kingbirds (Tyrannus tyrannus) are smaller than robins they’re called kings because they win so many battles.
Attacks by Eastern Kingbirds on nest predators such as corvids, raptors, and even large, nonpredatory birds are legendary. Aggressiveness increases the chances that an active nest will fledge young.
Unsuspecting Blue Jays have been knocked out of trees or driven to ground to seek shelter under bushes. Flying crows, all Buteo hawks, Northern Harrier and basically all raptors are attacked whenever they enter kingbird’s defended space.
When an eastern kingbird is especially annoyed it displays the red crown that’s usually hidden under dark head feathers. This one is thinking about attacking someone maybe a predator, maybe another kingbird, or maybe any bird that dares to enter his territory.
[The kingbird] also uses a particularly startling display during vigorous attacks on humans and presumably other predators. While in steep dive toward predator’s head, an Eastern Kingbird may expose and raise red crown patch and open mouth wide to reveal red gape. The effect is dramatic and has caused at least one human to nearly lose his grip and fall from a tree (M.T.Murphy).
