Seen This Week: Heavy Rain and Flash Floods

High water on Monongahela River at Duck Hollow, 2 June 2025 (photo by Kate St. John)

7 June 2025

When I stopped by Duck Hollow on Monday 2 June the Monongahela River was so high that the mud bar was totally submerged. If killdeer nested there this spring, the flood ended their breeding season.

At first the high water was a mystery because it hadn’t rained hard in Pittsburgh but this water came from last week’s heavy rain in West Virginia. It took a while to come downstream.

Pittsburgh is getting its own taste of flooding this weekend. Yesterday isolated thunderstorms dropped more than an inch of rain in some areas and caused immediate flash floods.

6 June 2025 video embedded from CBS Pittsburgh on YouTube

Much of the destruction will be cleared away today but it won’t be permanent. Tomorrow, Sunday 8 June, 1.2 inches of rain are predicted in intense downpours at 9am and thunderstorms at 1pm.

The weather will be challenging for Phipps BioBlitz tomorrow.

All 3 Pitt Peregrines Have Flown

Peregrine juvenile, probably Blue, at 38SW under the (offline) CL Tourcam (photo by Kate St. John)

6 June 2025

When we arrived yesterday for Fledge Watch at Schenley Plaza, we could tell that all three juveniles had flown(*). None were visible on the camera or nestrail and though I walked around the Cathedral of Learning looking for fledglings, none were visible anywhere. It was hot.

At noon we noticed a juvenile silently perched in the shade under the CL tourcam. It was Blue Girl. I saw her blue tape through my scope. She preened and sometimes opened her wings, a motion that says, “Here I am, parents, in case you want to bring food.” If she was really hungry she would have whined.

Peregrine juvenile grooming at 38SW (photo by Kate St. John)
Peregrine juvenile, probably Blue, at 38SW under the (offline) CL Tourcam, 5 June 2025 (photo by Kate St. John)

A few minutes later we saw Carla feeding a juvenile on the opposite corner at 38SE.

Carla feeding a juvenile at 38SW, 5 June 2025 (photo by Kate St. John)
Carla feeding a juvenile at 38SW, 5 June 2025 (photo by Kate St. John)

Now that the juvenile peregrines are hard to find, Fledge Watch is over.

(*) My guess on when they flew: One or two probably fledged on the afternoon of 4 June and the remainder yesterday morning 5 June.

Another Rarity: Beautiful Black Tern Stays Four Days

Black tern at Imperial Main Pond, 1 June 2025 (photo by Steve Gosser)

5 June 2025

Spring migration in Pittsburgh has been unusual this year. In Allegheny County at least four rare birds have stopped by on their way north.

Black terns (Chlidonias niger) are gorgeous in breeding plumage with a black head and underparts and gray-white back and wings. In flight the bird is mesmerizing while it hunts over water for insects and fish or circles up to view the landscape. At any moment it changes its flight style to resemble a butterfly, a swallow, a nighthawk, a flycatcher or a tern.

Black tern at Imperial Main Pond, 1 June 2025 (photo by Steve Gosser)

These videos are not from Imperial but they show why black terns are so beautiful in flight.

video embedded from BirdWatchingSamsung on YouTube
video embedded from Scott Ramos on YouTube

During its brief stay in Allegheny County over 50 eBirders stopped by to see the black tern and many took photos.

Those embedded below from Macauley Library (Ezra White, Rob Hooten, John Drake, Phillip Rogers) show a sequence of black tern behavior as the bird catches a fish: hovering, diving, coming up with a fish, flying away, resting on the grass.

Black Tern Hunting Sequence, Catching a Fish at Imperial Main Pond

This black tern was the best I’ve ever seen, closer than all the others plus he stood on the ground for a while (a first for me).

Black tern at Imperial Main Pond (photo by Charity Kheshgi)

He also had something to say…

Black Tern Vocalizing at Dusk

Because Allegheny County only sees black terns in migration it will probably be many years before another comes again.

Black tern range: blue=non-breeding, yellow=migration, orange=breeding (map from Wikimedia Commons)

We were lucky it visited in spring when it was beautiful. Black terns are not black in autumn as shown in non-breeding plumage in Ohio, September 2014.

Black tern on fall migration, Sept 2014, Bethel, OH (photo from Wikimedia Commons)

Indeed the bird was beautiful last weekend in Pittsburgh.

Mine! Mine! Mine! and Fledge Watch News

Mine! at the Pitt peregrine nest, 3 June 2025, 7:04pm (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

4 June 2025

The juvenile Pitt peregrines are maturing quickly. Yesterday morning Blue Girl lagged behind her brother (Green) and sister (Yellow) after those two left the nestbox the day before. By yesterday evening Blue had more than caught up.

Having spent most of her day outside the nestbox, Blue Girl jumped in at 7pm to snatch Yellow’s dinner. At the end, Green Boy stops in for a taste while his sisters are preoccupied. Mine! Mine! Mine!

embedded video from the National Aviary falconcam at the Univ of Pittsburgh

Fledge Watch News from Tuesday 3 June, 11:30a-12:30p:

Fledge Watch on 3 June 2025 (photo by John English)

Yesterday was sunny and increasingly hot. At 11:30a the juvies walked the nestrail and flapped their wings but by noon two were snoozing on the nestrail while the third slept in the shade inside the nestbox.

It’s hot. Two juvies on the nestrail, 3 June 2025, 12:11pm (photo by Kate St. John)

Today will be even hotter — 88°F — which means the youngsters will probably be hiding in the shade during today’s Fledge Watch. Hmmm.

If they are in the nestbox you can watch them on camera at the National Aviary falconcam at the University of Pittsburgh’s Cathedral of Learning.

Fledge Watch News and Now an Empty Nest

Carla on the roof, preening, while a juvie stretches her leg, 2 June 2025 (photo by Kate St. John)

3 June 2025

Yesterday at Pitt Peregrine Fledge Watch the weather was beautiful and so were the peregrines.

Pitt Peregrine Fledge Watch, 2 June 2025 (photo by John English)

When we arrived at 4:30pm two juveniles were on the nestrail: the male (Green Boy) and one female (Yellow Girl). Notice their size difference!

Two juvies on the nestrail, 2 June 2025 (photo by John English)

We figured out which female was topside by noting Blue tape on the bird in the nestbox. She exercised her wings a lot.

Blue exercises her wings at the green perch, 2 June 2025 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

Meanwhile on the nestrail, one of the juvies walked all the way to the right to perch above the nestbox.

Juvenile perched above the nestbox, 2 June 2025 (photo by Kate St. John)

The second juvie flapped and ran to the righthand side — using the nestrail like a runway — and was on hand for Ecco’s food delivery. (Notice the excited wings-open on that juvie!)

Two juvies plus Ecco on the nestrail, 2 June 2025 (photo by Charity Kheshgi)

Down in the nestbox Blue Girl missed out. Her parents were delivering food to the nestrail, not to the nest, so she would come topside.

Blue was still down there when Green Boy came for a visit at 7:25pm and discovered the fun of climbing the snapcam wall.

Green Boy stops by for a visit, 2 June, 7:25pm (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

You’d think he was posing, but no. He’s looking over the nestrail.

Green Boy looks over the nestrail while Blue stands below, 2 June 2025, 7:36pm (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

This morning Blue was done with feeling left out. At 6:38am she climbed up to the nestrail …

Blue ledge-walks out of the nest, 3 June 2025 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

… and now the nest is empty.

Empty nest, 3 June 2025, 7:22am (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

Join me at Schenley Plaza today at 11:30am – 12:30am for Pitt Peregrine Fledge Watch. Bring binoculars if you have them. I’ll bring my scope.

Will one of the juvies fly today?

p.s. At 8:10am Ecco came to the nestbox for a respite from the “kids.”

Ecco is at the nestbox, 3 June 2025, 8:23am (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

Vegetative Embrace

Woody vine embraces a tree branch, Raccoon Wildflower Reserve, 26 May 2025 (photo by Kate St. John)

2 June 2025

Animals embrace and release but when plants wrap around each other the result is often permanent. Sometimes an embrace is intentional, sometimes not.

Intentional
  • Almost like a snake, the woody vine pictured at top intentionally wrapped itself around a tree branch. But then it stopped growing and left the two locked in a vegetative embrace.
  • Dodder (Cuscata), pictured below, is a parasitic native annual in the morning glory (Convolvulaceae) family that intentionally wraps itself closely around a plant stem. It then inserts very tiny feelers between the cells and sucks nutrients from its host.  As an annual, it starts growing from seed but loses its soil-based roots when it has found a really good host.
Dodder more-than-embracing another plant, June 2017 (photo by Kate St. John)
  • Porcelain berry (Ampelopsis glandulosa) and grapevine intentionally drape themselves on trees and shrubs to lift themselves above the canopy. When this vine fell it embraced the oak.
Fallen vine embraces the oak it fell from, Moraine State Park, October 2022 (photo by Kate St. John)
  • Some plants have leaves that clasp the stem, circled in pink below. Botanists: Can you tell me the name of this plant? I forgot to note it when I took the photo at Raccoon Wildflower Reserve.
Alternate leaves clasp the stem, Raccoon Wildflower Reserve, 26 May 2025 (photo by Kate St. John)
Unplanned, Inadvertent

There are also inadvertent vegetative embraces, some of which are temporary.

  • Two trunks of the same species grew so close together that they fused at the base in this permanent embrace.
Two trees growing in a close embrace, January 2010 (photo by Kate St. John)
  • When this skunk cabbage put up shoots in the spring, one of them speared a dead leaf whose ribs now prevent the skunk cabbage from opening. Temporary embrace? I like to rescue these plants, especially mayapple and trillium, by pulling off the dead leaf. I can’t remember if I rescued this one.
Dead leaf, speared by an emerging skunk cabbage leaf, prevents it from unfurling, April 2025 (photo by Kate St. John)

Peregrine Update Southwest PA, 1 June

Mother peregrine at Tarentum, Saturday 24 May 2025 (digiscoped by Kate St. John)

1 June 2025

Lots of news today at the peak of Peregrine Season in Southwestern Pennsylvania. This report is “double-long.”

Cathedral of Learning, Univ of Pittsburgh

The Pitt peregrine chicks are getting closer to First Flight but yesterday was certainly not the day. As you can see from Saturday’s slideshow and Day In A Minute video below, they felt comfortable flapping on the green perch but none of them took the next step of walking away from the nestbox.

embedded video from the National Aviary falconcam at the University of Pittsburgh’s Cathedral of Learning.

Male peregrine chicks fly at a younger age than females because their lighter weight makes it easier to get airborne. The Cathedral of Learning male is three days younger than his sisters so he will probably be ready for takeoff when they are.

Watch their antics on the National Aviary falconcam at the University of Pittsburgh’s Cathedral of Learning. Join me this week at Schenley Plaza for Pitt Peregrine Fledge Watch. (Click the link for dates and times.)

Downtown Pittsburgh

UPDATE! Jeff Cieslak visited Third Avenue on Friday and found four, yes 4, peregrine chicks at the Downtown Pittsburgh nest. This crew looks as close to fledging as the Pitt peregrines. It’s going to be a big week.

Four peregrine chicks at Third Avenue nest, Downtown Pittsburgh, 30 May 2025 (photo by Jeff Cieslak)

Jeff also saw Terzo watching the sky …

Terzo near the Third Avenue nest, Downtown Pittsburgh, 30 May 2025 (photo by Jeff Cieslak)

… and his mate watching the nest from across the street.

Female (mother) peregrine at Third Avenue, Downtown Pittsburgh, 30 May 2025 (photo by Jeff Cieslak)

I stopped by on Saturday when it was cold and gray and saw only one chick and his mother dozing at the ledge edge.

One chick plus female peregrine at Third Avenue nest, Downtown Pittsburgh, 31 May 2025 (photo by Kate St. John)
East Liberty Presbyterian Church, Pittsburgh

In May three chicks were confirmed at the East Liberty Presbyterian steeple. Based on this 23 May photo my guess is that they will fledge around 17-22 June. Exciting days ahead!

Three peregrine chicks at East Liberty Presbyterian Church steeple, 23 May 2025 (photo from Ed Moore)

Adam Knoerzer also reports that the male (father) peregrine is noticeably busier this spring now that he is feeding three chicks instead of the one last year.

Male peregrine flying with prey to East Liberty Presbyterian Church steeple, 26 May 2025 (photo by Adam Knoerzer)

The male takes a break to warm up in the sun.

Male peregrine takes a break in the sun at East Liberty Presbyterian Church, 26 May 2025 (photo by Adam Knoerzer)
Sewickley Bridge, Ohio River

The Ohio River is so high with heavy rain that the Sewickley Bridge nestbox has been hard to observe. Jeff Cieslak found a less than ideal place to stand on 26 May for this glimpse of the three chicks. Lots of rain in West Virginia in the past couple of days means the Ohio River will stay high into this week.

Three chicks in Sewickley Bridge nestbox, 26 May 2025 (photo by Jeff Cieslak)
Tarentum Bridge, Allegheny River

Dave Brooke is keeping tabs on the Tarentum Bridge peregrine family where he notes that the three youngsters fledged on or after 24 May but still hang out at the bridge. They are very photogenic.

Juvenile peregrine flapping atop the nestbox, 31 May 2025 (photo by Dave Brooke)
All three juvenile peregrines at Tarentum Bridge, 29 May 2025 (photo by Dave Brooke)

I stopped by on 24 May and was able to digiscope a youngster picking at a bone and his mother perched in the superstructure (at top) — so far the best digiscoped photo I’ve ever taken of a peregrine falcon.

Juvenile peregrine eating at the Tarentum Bridge, 24 May 2025 (digiscoped by Kate St. John)
Westinghouse Bridge, Turtle Creek near Monongahela River

On 24 May Dana Nesiti watched the parents at Westinghouse Bridge call to chick(s) in the scrape. Eventually one chick came to the ledge edge.

One chick appears at the ledge edge, Westinghouse Bridge, 24 May2025 (photo by Dana Nesiti)
SUMMARY FOR SOUTHWEST PA

Southwestern Pennsylvania peregrine sites are listed in the table below. Help fill in the blanks ed below by visiting a site near you. Leave a comment if you find anything!

Woolly Gall on an Oak

Woolly oak gall, Raccoon Wildflower Reserve, 25 May 2025 (photo by Kate St. John)

31 May 2025

Oak apple galls are shiny and brown so I was surprised to find this fuzzy one on a white oak stem. This not a fuzzy version of the oak apple gall. This is a woolly oak gall made by a completely different species of gall wasp (family Cynipidae).

Woolly oak galls are made by Callirhytis seminator, “the wool sower,” which places its galls only on white oaks and only in the spring.

The wasps are tiny, 1/8″ long, and have many predators including larger parasitic wasps. They do not sting humans.

Wool sower gall maker (Callirhytis seminator), Lisa Ames University of Georgia via bugwood.org

Gall wasps have a two-generation alternating cycle: One generation produces stem galls, and the wasps that emerge from that stem gall mature and lay their own eggs in leaf galls. The wasps that emerge from the leaf gall mature and produce stem galls. Scientists do not know what the alternate wool sower wasp gall looks like.

WIkipedia: Callirhytis seminator account

The gall I found and the one pictured below were made by the stem-gall generation.

Woolly oak gall, Jim Baker, North Carolina State University via bugwood.org

If you open the gall it has seed-like structures inside that are actually plant material, not the insect. The larvae are white and fat, have no legs.

Interior of a woolly oak gall, made by Callirhytis seminator, Jim Baker, North Carolina State University via bugwood.org

As the gall matures it turns pink.

Woolly oak gall made by Callirhytis seminator (photo by Terry S. Price, Georgia Forestry Commission via bugwood.org)

If I go back to Raccoon Wildflower Reserve in a few weeks and find the same tree the gall won’t look the same. Will it even be there?

What About Names?

Three peregrine chicks at Pitt peregrine nest, 30 May 2025 (photo from the National Aviary streaming camera at Univ of Pittsburgh)

30 May 2025

Wondering about names for Pitt’s peregrine chicks?  They already have them, named for the colored tape affixed to their silver USFW bands.

  • Yellow = first sister, also known as Yellow Girl
  • Blue = second sister, a.k.a. Blue Girl
  • Green = the male, a.k.a. Green Boy

Why colors?

The long answer is explored at this FAQ How Do Peregrines Get Their Names? but in short:

  • In Pennsylvania it is the policy of the PA Game Commission not to name wild birds, including peregrine falcons at banding.
  • Nestlings/fledglings are very hard to tell apart so for ease of identification, the PA Game Commission puts colored tape on the USFW band.
  • Adult names are optional. In Pittsburgh our tradition is:
    • If the adult is banded we try to find out if it already has a name. If not … 
    • The nest site’s main monitor may name the adult(s) if they wish.

For the nestlings, PGC uses the same tape colors every year so we reuse the same names: Yellow, Green, Blue, Red, White, Silver (no tape).  The tape is temporary (it eventually falls off) but it’s useful in late spring and early summer when the peregrine family is still together in the vicinity of the nest.

Three peregrine chicks at Pitt peregrine nest, 30 May 2025 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

After they’ve fledged, if we can see the tape color we describe a bird’s location like this, “Green Boy is on the Heinz Chapel roof.” 

Maybe he will go there next month.

Don’t miss this explanation of how peregrines get their names. It includes a quote from Old Possum’s Book of Practical Cats. 🙂

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Answers to Blue Band & Tracking Our Banded Peregrines

Bands on second female chick, including view of blue tape (photo by Mike Faix, National Aviary)

29 May 2025

Here are some answers to your recent questions about the Pitt peregrines’ bands.

The Blue Band: This week a blue band showed up on the nestbox gravel and several of you asked if it had come from one of the peregrines. No, the blue tape is still on the female chick.

There’s a blue band on the nest gravel. It’s not from a peregrine, 28 May 2025 (photo from the National Aviary streaming camera at Univ of Pittsburgh)

In fact it’s not a peregrine band. Ted Nichols saw it come in on the leg of a prey item the chicks ate earlier this week. It may have been on a northern flicker.

Band reports: Will we hear where these banded chicks go later in life?

The USGS Bird Banding Lab (BBL) is the repository for all bird band data. When birds are banded the bander sends the numbers to BBL. When a band sighting is reported to BBL, they report the sighting to the bander, in this case the PA Game Commission. Eventually I hear about it and report it on the blog. BUT

The banding system is about to collapse. The “Big Beautiful Bill,” which passed the House on 22 May, will eliminate BBL and its home, the Eastern Ecological Science Center in Laurel Maryland.

“The U.S. Geological Survey’s Patuxent Wildlife Research Center in Laurel, now called the Eastern Ecological Science Center, will be closed if the Congressional budget passes in its current form [NOTE: it passed on 22 May],” said Gregg Petersen, president of the Howard County Bird Club. “The center was started in 1923 and became the gold standard for wildlife research for the world.” It is home to the USGS Bird Banding Lab, which supplies bands and manages banding data on a national level.

Business Monthly: federal cuts could end wildlife research labs in Laurel, across U.S.

If the bill passes the Senate in its present form, the BBL will close and there will be no national coordination, collection and reporting of banding data. So we will not hear about our banded birds in the future.

Perhaps your Senators don’t know about the importance of BBL. They are probably busy, though. The BBL is small potatoes compared to the bigger issues in the Big Beautiful Bill.