How a Vine Wraps a Twig

Hops vine (photo from Wikimedia Commons)

24 May 2024

If you drink beer you’re familiar with the flavor of hops which is used as a bittering, flavoring, and stability agent in beer. Depending on the variety, hops can also add floral, fruity, or citrus flavors and aromas.

The hops plant itself, Humulus lupulus, is a perennial vine that vigorously twines itself around uprights and strings in the hopfield.

Hops vine climbing a twig (photo from Wikimedia Commons)

To do so it uses to a motion called Circumnutation.

Circumnutation refers to the circular movements often exhibited by the tips of growing plant stems, caused by repeating cycles of differences in growth around the sides of the elongating stem.

Wikipedia: Nutation (botany) account

The wrapping happens slowly, but if you speed it up here’s what it looks like.

video embedded from gohepcat on YouTube

Air Pollution Makes Pollen Allergies Worse

Kentucky bluegrass, Poa pratensis, a common lawn grass in PA (photo from Wikimedia Commons)

23 May 2024

Talk about allergies! Oak tree pollen is finally diminishing in Pittsburgh, but grass pollen allergies are ramping up. I’m allergic to lawn grass. I feel it already.

Red fescue, a common lawn grass in PA (photo from Wikimedia Commons)

A study last year explained why we suffer more in the 21st century. Pollen season is getting worse every year because climate change is lengthening the growing season and increasing pollen production.

Unfortunately, a recent study explains that air pollution makes allergies worse. Pittsburgh has some of the worst particulate air pollution in the U.S.

“Plants that are grown in pollution-stressed situations are known to release more allergens,” says Elaine Fuertes, a research fellow at the National Heart and Lung Institute, Imperial College London.

Depending on the plant species, air pollutants can change the chemical composition of pollen, increasing the potency of pollen allergens and triggering stronger allergic reactions in people. …

…Air pollutants like particulate matter and nitrogen oxides may also make the exine — the outer coating of pollen grains — from some plant species more fragile and, therefore, more likely to rupture into smaller fragments that can penetrate deeper into the lungs.

Yale Climate Connections: Allergy symptoms got you down? Blame pollen AND air pollution.

Learn more about the interplay between pollen, air pollution and our allergies at Yale Climate Connections article below.

BONUS FACTLET: While looking for lawn grass photos I learned that Pennsylvania’s most common lawn grass, Kentucky bluegrass (Poa pratensis), is not native to Kentucky nor to North America. Poa pratensis is from Europe, North Asia and the mountains of Algeria and Morocco.

Two Peregrine Chicks Banded at Pitt Today

PGC’s Patti Barber prepares to band one of the Pitt peregrine chicks, 21 May 2024 (photo by Mike Faix, National Aviary)

21 May 2024

This morning two peregrine chicks were banded at the University of Pittsburgh’s Cathedral of Learning by Patti Barber, Endangered Bird Biologist from the PA Game Commission (PGC).

As soon as Patti began collecting the chicks, the parents Carla and Ecco strafed the building to drive her away. Carla herself is banded but this was her first time experiencing it as a mother. She was fierce in protecting her chicks.

Adult peregrine reacts to PGC’s Patti Barber collecting chicks at the nest, 21 May 2024 (photo by Aimee Obidzinski, Univ of Pittsburgh)

Indoors, the chicks were given health checks (they are very healthy!), weighed to determine their sex, and given two leg bands: a black/green color band that can be read through binoculars and a silver USFW band.

Patti Barber displays the band to be used on the larger of the two chicks at the Cathedral of Learning, 21 May 2024 (photo by Aimee Obidzinski, Univ of Pittsburgh)

Patti put colored tape on the silver USFW bands so we can identify the birds by color on the falconcam. The smaller chick is yellow, the larger chick is blue.

Interestingly the larger of the two youngsters (blue) is clearly female, weighing in at over 1000g. The smaller bird (yellow) weighed 730g, just above the borderline that designates males as less than 700g and females as more.

Yellow was officially listed as “sex undetermined” but my guess is that he’s male. The Cathedral of Learning has seen a few male peregrine chicks weighing 710-720g. (Dorothy’s in 2009, 2010 and Morela’s in 2022). We humans won’t know for sure if this bird is male until we see him nest.

Smaller of the two chicks receives his color band (photo by Mike Faix, National Aviary)

“Blue” calmly waited while we all took photos.

Female peregrine chick (Blue) on Banding Day, 21 May 2024 (photo by Kate St. John)
Female peregrine chick banded at Cathedral of Learning (blue tape), 21 May 2024 (photo by Kate St. John)

In less than half an hour the chicks were back at the nest and their lives returned to normal.

Meanwhile we got a glimpse of the unhatched egg which Patti collected for testing.

Unhatched egg at peregrine nest collected for testing, 21 May 2024 (photo by Kate St. John)

The chicks will grow up rapidly in the next two weeks and leave the camera view by the end of the month.

Stay tuned for the Fledge Watch schedule at Schnenley Plaza at the end of this month and early June.

p.s. A Big Thank You goes out to everyone who made this day possible. (Apologies to anyone I’ve missed in this list.)

  • The University of Pittsburgh for being such a great peregrine landlord, for publicizing the peregrines, and for hosting the banding.
  • The PA Game Commission for their commitment to banding the peregrine chicks at the Cathedral of Learning. (Peregrine banding in PA is rare nowadays because the birds are no longer endangered / threatened.)
  • The National Aviary for broadcasting the Pitt peregrines’ nest from their falconcam and for organizing the banding.

(photo credits are in the captions)

Big Moves Yesterday, Banding Today

Peregrine chicks at Cathedral of Learning nest, 28 days old, 20 May 2024 (photo from the National Aviary falconcam at Univ of Pittsburgh)

21 May 2024

Yesterday was a big day for the Pitt peregrine chicks. The smaller chick made two new moves: He jumped up on the green perch and he snatched prey from his mother. Today will be even bigger. It’s Banding Day! The event is closed to the public (the room has a very strict occupancy limit!) but you’ll see the start and end on the falconcam.

Big Moves Yesterday: Green perch & Food snatch

Both big moves are shown in this video of snapshots.

video from the National Aviary snaphot camera at Univ of Pittsburgh

Here’s a closer look at the snatching episode as seen on the streaming cam: Carla was about to kill and pluck a chimney swift when the male chick snatched it. Chaos ensued! When Carla couldn’t retrieve it she shouted to Ecco while the other chick begged loudly.

Male peregrine steals incoming prey from Carla. Everyone shouts, 20 May 2024, 17:21 (video from the National Aviary falconcam at Univ of Pittsburgh)

Banding Day Today:

You’ll know when Lead Bander Patti Barber of the Pennsylvania Game Commission goes out on the ledge to retrieve the chicks because you’ll hear Carla and Ecco shouting and the youngsters will huddle at the back of the box.

When the chicks are brought indoors they will receive health checks and leg bands and be returned to the nest in less than half an hour.

Stay tuned later today for banding photos and an update on the event.

(photo from the National Aviary falconcam at Univ .of Pittsburgh)

City Tornado Visits the Zoo

screenshot from WTAE-TV Pittsburgh video embedded below

20 May 2024

Late Friday afternoon I saw a very dark cloud outside my window that looked almost flat like a wall. The horizon obscured the bottom edge as the cloud moved away toward Highland Park.

Shortly thereafter the cloud spawned a tornado that touched down at the Pittsburgh Zoo & Aquarium. The National Weather Service rated it EF1, the strongest of four tornadoes in the Pittsburgh metro area that afternoon.

Preliminary Damage Survey Results, Highland Park tornado, 17 May 2024 (report from NWS via
video embedded from WTAE-TV Pittsburgh

Fortunately no people or animals were injured and the most dramatic damage was a car flattened by a tree in the Zoo parking lot. The video below shows local reactions including people waiting in a car on the Highland Park Bridge for the tornado to pass. Glad I was not there!

video embedded from WTAE-TV Pittsburgh

Those of you who live in severe tornado regions probably think Pittsburghers are wimps to get excited about an EF1 tornado but in fact tornadoes are rare here.

video embedded from KDKA, CBS Pittsburgh

The last time one touched down in the City of Pittsburgh was in 1998. Read more about it here.

Yesterday at Schenley Park, 5/18

Female red-winged blackbird scans the sky while collecting nesting material, Schenley Park, 18 May 2024 (photo by Charity Kheshgi)

19 May 2024

The pouring rain ended yesterday morning just in time for our walk in Schenley Park.

Outing at Schenley Park, 18 May 2024 (photo by Kate St. John)

From midnight until 8am 1.16 inches of rain fell. All the streams were rushing and Panther Hollow Lake was muddy and full. It looked as if the lake had risen 8-12 inches since I saw it the day before.

Among the cattails we found busy red-winged blackbirds including a female gathering nesting material who scanned the sky for predators (at top). The last time I saw red-wings building nests was in mid April. Was this a second nesting? Or had high water flooded nests that now were being rebuilt?

Female red-winged blackbird collecting nesting material, Schenley Park, 18 May 2024 (photo by Charity Kheshgi)

Why was the female blackbird scanning the sky? She probably saw a red-tailed hawk shuttling food to three youngsters in their nest on the bridge.

3 youngsters in red-tailed hawk nest, Schenley Park, 18 May 2024 (photo by Charity Kheshgi)

All told we saw 27 species of birds plus one doe, five bucks and an active beehive.

I’m so glad it stopped raining!

Our checklist is here and listed below.

Schenley Park, Allegheny, Pennsylvania, US
May 18, 2024 8:30 AM – 10:45 AM, 27 species

Mourning Dove (Zenaida macroura) 5
Chimney Swift (Chaetura pelagica) 1
Ruby-throated Hummingbird (Archilochus colubris) 1 Perched on snag
Red-tailed Hawk (Buteo jamaicensis) 4 3 youngsters in nest
Red-bellied Woodpecker (Melanerpes carolinus) 2
Peregrine Falcon (Falco peregrinus) 3 Adult perched on nest rail, 2 young on falconcam
Eastern Wood-Pewee (Contopus virens) 2
Eastern Phoebe (Sayornis phoebe) 1
Red-eyed Vireo (Vireo olivaceus) 4
Blue Jay (Cyanocitta cristata) 8
Carolina Chickadee (Poecile carolinensis) 2
Northern Rough-winged Swallow (Stelgidopteryx serripennis) 3
House Wren (Troglodytes aedon) 4 House wrens usually nest at PH Lake in the streetlight hoods. Singing wren near the streetlight went into the hood.
Carolina Wren (Thryothorus ludovicianus) 2
European Starling (Sturnus vulgaris) 3
Gray Catbird (Dumetella carolinensis) 4
Wood Thrush (Hylocichla mustelina) 1 Heard
American Robin (Turdus migratorius) 30
House Finch (Haemorhous mexicanus) 6
American Goldfinch (Spinus tristis) 4
Song Sparrow (Melospiza melodia) 3
Baltimore Oriole (Icterus galbula) 4
Red-winged Blackbird (Agelaius phoeniceus) 8 (PHLake very high after lot of rain. Perhaps flooded RWBL nests)
Brown-headed Cowbird (Molothrus ater) 1
Common Grackle (Quiscalus quiscula) 2
Tennessee Warbler (Leiothlypis peregrina) 2
Bay-breasted Warbler (Setophaga castanea) 1 Heard

Seen This Week

Blackpoll warbler, Presque Isle, 12 May 2024 (photo by Charity Kheshgi)

18 May 2024

Best birds this week were seen at Presque Isle State Park on Sunday 12 May while birding with Charity and Kaleem Kheshgi. At Leo’s Landing many of the birds were at eye level including this blackpoll warbler and the barn and bank swallows.

Barn and bank swallows, Presque Isle, 12 May 2024 (photo by Charity Kheshgi)

Even the treetop birds, like this yellow-throated vireo, cooperated for photographs.

Yellow-throated vireo, Presque Isle, 12 May 2024 (photo by Charity Kheshgi)

Was this redstart was looking askance at us? Or eyeing a bug?

American redstart, Presque Isle, 12 May 2024 (photo by Charity Kheshgi)

I had high hopes for the Bird Banding at Hays Woods on Wednesday 15 May but we were in for a surprise. No birds to band! Bummer. 🙁 This restart, banded earlier in the week, shows what we could have seen.

American redstart at Bird Lab banding (photo by Kate St. John)

After we left the banding station we had good looks at a scarlet tanager and found this Kentucky flat millipede (Apheloria virginiensis). It’s colored black and orange because it’s toxic.

  • It secretes cyanide compounds as a defense. Don’t touch it!
  • You might find one perched and dying on top of a twig. That’s because it can host the parasitic fungus Arthrophaga myriapodina which causes infected individuals to climb to an elevated spot before death (per Wikipedia). Eeeew.
Centipede Aphelosia virginiensis, Hays Woods, 15 May 2024 (photo by Kate St. John)

This week there were flowers in the tulip trees (Liriodendron) obscured by thick leaves. This flower came into view when a squirrel bit off the twig and didn’t retrieve the branch.

Tulip tree flower and leaves, 16 May 2024 (photo by Kate St. John)

Instead of rain on Wednesday we had a beautiful sunrise.

Sunrise 14 May 2024 (photo by Kate St. John)

To make up for no rain on Wednesday it’s pouring right now on Saturday.

The Tenants Have a Family

banner from Gwyllt Hollow Sitting Room Nuthatches

17 May 2024

In early April WildlifeKate (@katemacrae) introduced us to a pair of Eurasian nuthatches (Sitta europaea) who were remodeling a nestbox she’d provided at Gwyllt Hollow in southern Wales.

The sitting room was beautiful before they yanked out the decorations, added mud to the walls, and filled the room with dried leaves up to the chair rail.

Before remodeling: screenshot from April 09 video from WildlifeKate at Gwyllt Hollow

Having built the nest to their liking the female laid eggs that hatched last Sunday 12 May. (yes there’s a rooster on the sound track.)

video embedded from WildlifeKate at Gwyllt Hollow

This pair now has a large and hungry family.

video embedded from WildlifeKate at Gwyllt Hollow

The chicks are growing fast. As of this morning their eyes are still closed.

Watch the live feed at Gwyllt Hollow – Sitting Room Nuthatches. See the adults hand off food to feed their growing the family.

NOTE: This live stream is 5 hours ahead of U.S. Eastern Time.

Have You Seen Any Nighthawks?

Common nighthawk, Tower Grove Park, Oct 2020 (photo from Wikimedia Commons)

16 May 2024

When I was a kid in the 1960s common nighthawks (Chordeiles minor) were so common that they attracted my notice and inspired my love for birds. In the late 1970s many flew above my neighborhood on summer nights, hawking moths over the Magee Field ballpark lights. In the 1990s their population began a steep decline and by the late 2000s I noticed it in my neighborhood. This year I haven’t seen a nighthawk yet. Their decline has gotten worse in the last 20 years.

Nighthawks are nightjars and they are all in trouble including whip-poor-wills and chuck-wills-widow.

How many nighthawks are left? Where are they now?

You can help answer these questions by participating in the 2024 Nightjar Survey conducted by the Center for Conservation Biology(*).

The survey window for the entire continental US opened yesterday, running from 15 May to 30 May.

Nightjar Survey Locations during 15 May — 30 May Window

Interestingly you only have to count nighthawks by the light of the moon because they call more often when the moon is shining. The next full moon is 23 May, right in the middle of the survey period.

Rainbow around the nearly full moon, North Park, Pittsburgh, 16 March 2022, 8:01pm

Check out the survey instructions PDF here or on their website at (*)Update on 18 May: The website is temporarily unreachable.

Read more about the decline of nighthawks in this vintage article from 2009.

p.s. I participated in the nightjar survey with Michelle Kienholz in 2018. The maximum number we counted at any one stop was only two.

See survey results from all years here.

Spectacular Skies Over Pittsburgh

Rainbow just before sunset in Pittsburgh, 11 May 2024, 7:30pm (photo by Kate St. John)

15 May 2024

Last week the sky above Pittsburgh was spectacular over and over again.

  • Stunning storms on May 8
  • Beautiful sunrise on the 9th
  • Northern lights on the 10th
  • Double rainbow on the 11th.

No storm photos from me (!incredibly close lightning) but I photographed sunrise on the 8th.

Sunrise on 9 May 2024 (photo by Kate St. John)

Alas I missed the northern lights on Friday.

But was treated to the double rainbow on Saturday (with raindrops on the window).

Rainbow just before sunset in Pittsburgh, 11 May 2024, 7:29pm (photo by Kate St. John)

Photographer Dave DiCello takes dramatic photos of Pittsburgh every day from the West End overlook and captured every one of these spectacular sky events.

For more sky photos see:

This week is sunny or cloudy but nothing remarkable.

The sky is taking a break after a busy week.

(credits are in the captions)