Monthly Archives: March 2022

The Clean Up Crew Is Back

Turkey vulture in flight (photo from Wikimedia Commons)

31 March 2022

Have you noticed them lately?

Turkey vultures (Cathartes aura) are migrating over Pittsburgh during the warmest parts of the day. They returned to Hinckley, Ohio on 15 March. Now they’re here.

Since my first sighting of a lone turkey vulture on 10 March I now see groups of at least four every day, especially near their roosts.

Turkey vultures at the roost (photo from Wikimedia Commons)

Very soon we are going to appreciate that the Clean Up Crew has returned to eat the dead things that rot in warm weather.

Unlike us, vultures can always eat what they want. Find out why in this vintage article.

(photos from Wikimedia Commons; click on the captions to see the originals)

Cute and Confrontational

Red squirrel with peanut (photo from Wikimedia Commons)

30 March 2022

It’s hard to take a bad picture of an American red squirrel (Tamiasciurus hudsonicus). When they pose they look so cute that it’s hard to believe they are asocial, combative and confrontational.

Photogenic red squirrel (photo from Wikimedia Commons)

This sleeping squirrel seems to be saying, “I love you, tree.”

Sleeping red squirrel: “I love you, tree” (photo from Wikimedia Commons)

Ready to fight? Still cute.

Red squirrel looking pugnacious (photo from Wikimedia Commons)

Though they rarely encounter each other — perhaps for their own safety — red squirrels fight when there’s more than one. Most of their battles are a lot of shouting and chasing while the resident squirrel defends his territory.

Defending the midden (food store) is a matter of survival that’s learned in the first year of life. Juvenile red squirrels must find a territory and midden before their first winter or they won’t make it to next spring. Only 22% survive to one year old.

For a few, just 15%, their mothers bequeath them a territory but it still has to be defended. The red squirrels who survive are the most confrontational.

(photos from Wikimedia Commons; click on the captions to see the originals)

The Chase!

Bald eagle in pursuit (photo from Wikimedia Commons)

29 March 2022

Les Leighton had his camera set up at Canada’s Vancouver harbor when a drama played out in front of him. A gull zipped by with both a bald eagle and peregrine falcon pursuing it in flight. What was it about that gull that attracted two predators at the same time?

Watch the chase and notice the difference between the eagle’s and peregrine’s hunting techniques. Why did both of them give up?

The gull had a good day after all.

(video by Les Leighton “wetvideocamera” in Vancouver, BC, Canada)

Peregrine News Around Town, 28 March

Peregrine at the California Avenue Bridge (vicinity of McKees Rocks Bridge), 23 March 2022 (photo by Jeff Cieslak)

28 March 2022

Since my last update on 14 March a Big Thank You goes out to everyone who went looking for peregrines in Southwestern PA, especially to Jeff Cieslak, Dave Brooke and Dana Nesiti. Jeff’s photo, above, has a second message. If you ever doubted the sorry condition of Pittsburgh’s bridges take a look at the underside of the California Avenue Bridge. Yikes!

At every site except Speers/Belle Vernon at least one peregrine has been seen this month. At sites with eggs it’s common to see only one bird. (Click here for a regional map of these sites.)

Cathedral of Learning, Univ of Pittsburgh:

Morela and Ecco with first view of 4 eggs, 26 March 2022 (photo from the National Aviary falconcam at Univ of Pittsburgh)

From March 18 to 30 Morela laid 5 eggs (24-hour clock matches the falconcam).

  • 3/18/2022, 08:31
  • 3/20/2022, 20:09 (approx guess)
  • 3/23/2022, 04:40 (approx)
  • 3/26/2022, 06:32
  • 3/30/2022, 19:08

The overnight egg-times were hard to determine but her 4th egg was easy to see just before dawn. After the 4th she resumed incubation immediately.

I believe that incubation began on 23 March so we can expect Hatch Day on or about 26 April 2022. Watch the nest “live” on the National Aviary falconcam.

Downtown Pittsburgh:

Downtown peregrine at nest on Third Avenue, 23 March 2022 (photo by Jeff Cieslak)

From the top of Mt Washington on 23 March 2022 Jeff Cieslak photographed a peregrine on the nest ledge at Third Avenue Downtown. The pair has not been seen simultaneously since 17 March.

Note on the Gulf Tower: The nestbox was removed in 2019 during masonry repairs and reinstalled in Feb 2021. No peregrines. Not since 2017. The camera is not streaming. Observers in the building will let us know if the peregrines show up.

Monaca RR Bridge, Ohio River:

Railroad bridge over the Ohio River from Monaca to Beaver (photo by Kate St.John)
Railroad bridge over the Ohio River from Monaca to Beaver (photo by Kate St.John)

Dante Zuccaro now reports a single peregrine almost every day, seen from the mouth of the Beaver River, most recently on 27 March.

Ambridge-Aliquippa Bridge, Ohio River:

Ambridge Bridge with a peregrine on top, 20 Feb 2020 (photo by Kate St. John)

No news since 8 March. If you’re in the vicinity, please take a look.

Sewickley Bridge, Ohio River:

Peregrine on the Sewickley Bridge, 27 March 2022 (photo by Jeff Cieslak)

After frequently seeing both peregrines at the Sewickley Bridge Jeff Cieslak found only one on 27 March. I’m encouraged that this bird is perched on the pier rather than the superstructure since the underside of the bridge is a much safer place for youngsters. Perhaps they have eggs in a nest under the bridge.

McKees Rocks Bridge / Ohio River Blvd, Ohio River:

Peregrine on the smokestack near McKees Rocks Bridge, 22 March 2022 (photo by Jeff Cieslak)

On 22 March Jeff Cieslak saw a peregrine perched near Alcosan (which is near the McKees Rocks Bridge) but could not figure out where it came from. When it flew he followed it as best he could and returned the next day to investigate.

On 23 March he found a peregrine at the Ohio River Blvd bridge (below) which flew to the California Avenue bridge (shown at top). Perhaps this pair is nesting in the area of the McKees Rocks Bridge but not on it. Meanwhile, did you know that the decrepit California Ave bridge (at top) is rated in “fair” condition? Hmmm!

Peregrine at Ohio River Blvd Bridge, 23 March 2022 (photo by Jeff Cieslak)

Westinghouse Bridge, Turtle Creek:

Male peregrine comes in for a landing at Westinghouse Bridge, 26 March 2022 (photo by Dana Nesiti)

At the Westinghouse Bridge on 26 March Dana Nesiti watched the male bring in food and stash it near the nest area. He may have heard the female call from the nest but can’t be sure because a noisy train went by right then.

Male peregrine at Westinghouse Bridge, 26 March 2022 (photo by Dana Nesiti)

62nd Street Bridge / Aspinwall Riverfront Park, Allegheny River:

Aspinwall RR Bridge, 12 Feb 2022 (photo by Kate St. John)

On 15 March Andrew Mumma saw gulls harass a peregrine falcon perched on the Aspinwall Railroad Bridge, shown above. Where did the peregrine come from? We don’t know but the 62nd Street Bridge is not far away.

62nd Street and Highland Park bridges as seen from underneath Aspinwall RR bridge (photo by Kate St. John)

Look for peregrines at the 62nd Street Bridge from either side of the river — on the Pittsburgh side or Etna Riverfront Trail. Tell me what you see. (Click the links to see maps.)

Tarentum Bridge, Allegheny River:

Female peregrine at Tarentum Bridge, 22 March 2022 (photo by Dave Brooke)

When Dave Brooke visits the Tarentum Bridge now he sees only one bird at a time, as on 22 March above. On 19 March his distant observation of the nestbox indicated that the female may have laid her first egg. The male was perched alone that day.

Male peregrine at the Tarentum Bridge, 19 March 2022 (photo by Dave Brooke)

Graff Bridge, Rt 422, Kittanning, Allegheny River:

Graff Bridge, Kittanning as seen from Armstrong Trail, 2022 (photo by Kate St. John)

Dave Brooke found a peregrine at the Rt 422 Graff Bridge on 14 March (see this link). No news since then.

The best place to watch this bridge is from the Armstrong Trail near or under the Graff Bridge. Park here on Water Street in Manordale (click link) and walk north (upstream) on the Armstrong Trail. Tell me what you see.

Speers Railroad Bridge, Washington County, Monongahela River: No news since February. Any news at all — seen or “didn’t see” — would be welcome! Click here for a map of the best vantage point.

(photos by Kate St. John, National Aviary falconcam at Univ of Pittsburgh, Jeff Cieslak, Dana Nesiti, Dave Brooke and Wikimedia Commons)

Denuded Pine Cones

Central stem of a white pine cone missing all its seed scales, bracts & seeds, Moraine State Park, 24 March 2022 (photo by Kate St. John)

27 March 2022

On a walk last week in Moraine State Park we found a pile of pine cones in various stages of undress. Some were uneaten, some were half eaten and many were stripped bare like the stem above.

White pine cones at the red squirrel’s midden: uneaten to completely gone

The large debris pile called a midden included woody seed scales, pine straw, bract scales, and central stems but few seeds.

Close up of the midden shows many discarded seed scales, Moraine State24 March 2022

It was created while eating the seeds inside the cones.

Anatomy of a woody pine cone (image from Wikimedia Commons)

The midden was made by an individual red squirrel (Tamiasciurus hudsonicus), working alone.

We can know this because of the focus on pine cones, how the cones were denuded, and the sizeable midden. Conifer seeds make up the majority of the red squirrel’s diet and he defends his midden territory year-round against every other red squirrel.

Red squirrels are highly territorial and asocial with very few non-reproductive physical interactions. The majority of physical interactions are in male-female matings and between females and their offspring before the offspring disperse to their own territories. The non-reproductive physical interactions recorded (0.6% of all recorded behaviors in one 19-year study) were all instances of chasing an intruder from a territory.

Wikipedia Account: American Red Squirrel

The red squirrel is small and cute, but always eats alone.

Red squirrel on a tree branch (photo from Wikimedia Commons)

(photos by Kate St. John and from Wikimedia Commons; click on the captions to see the originals)

Here Today, Gone Tomorrow

Flowering cherry in Pittsburgh, 24 March 2022 (photo by Kate St. John)

26 March 2022

This week the elms, maples, ornamental cherries and northern magnolias began to bloom in Pittsburgh. Their flowers have not yet reached their peak and that’s a good thing. Tomorrow night the low will be 19 degrees F and will devastate the tender petals.

Above, an ornamental cherry shows off its delicate pink-white blossoms in the sun on Thursday 24 March. Below, a northern magnolia flower peeks out of its winter coat in Schenley Park on Tuesday 22 March.

Northern magnolia flower bud, 22 March 2022 (photo by Kate St. John)

Red maple flowers are either male or female. These female pistils are waiting for pollen from the male flowers. Pollen season is coming soon!

Red maple flowers, 22 March 2022 (photo by Kate St. John)

Cornelian cherry (Cornus mas), one of the earliest shrubs to bloom in western Pennsylvania, is a Eurasian member of the dogwood family. It can also look like an understory tree.

Cornelian cherry (Cornus mas) at Moraine State Park, 24 March 2022 (photo by Kate St. John)

Also blooming in yellow this week, forsythia is putting out tentative flowers.

Forsythia blooming (photo by Kate St. John)

And at Frick Park the hellebore planted near the Environmental Education Center is in full bloom (probably Hellebore odorus). I wonder if these nodding flowers will survive the cold.

Hellebore in bloom in Frick Park, 25 March 2022 (photo by Kate St. John)

Meanwhile I’m not worried about the new leaves on these hardy invasive plants. I doubt they’ll be damaged by the cold.

Bush honeysuckle leaf out in Frick Park, 21 March 2022 (photo by Kate St. John)
Privet leaf out in Oakland, 23 March 2022 (photo by Kate St. John)
Garlic mustard leaf out in Frick Park, 21 March 2022 (photo by Kate St. John)

Take a look at flowers today. They’ll be gone tomorrow night.

(photos by Kate St. John)

Not What It Appears To Be

Volcano? (photo from Wikimedia Commons)

25 March 2022

Some things are not what they appear to be.

The photo at top is a rocky peak on the Swiss-Italian border at Splügen Pass but the streaming cloud makes it look like a volcano. Click here to see that it’s simply a mountain (on the horizon at top right) in Google Street View.

Can water tilt sideways? It appears so at this pond in Scotland.

Optical illusion, tilted pond at Drummond Castle Gardens, Perth and Kinross, Scotland (photo from Wikimedia Commons)

How about this herd of horses in the National Geographic Picture of the Year? Click on the image to zoom in. Look closely and you will see zebras.

And finally there is the experiential illusion of a “gravity hill.”

A gravity hill, often referred to as a mystery hill, is a spot in the road where the layout of surrounding land and landmarks creates an optical illusion, making a slight downhill slope appear to be an uphill slope.

Skeptics have put the hills to the test, using magnetic detectors and levels. All indications suggest the hills are just illusions.

WGNTV gravity hills

There are three gravity hills in Pennsylvania. The most famous is in Bedford County.

There is also one in Pittsburgh … but do not visit when there is any traffic! Go on a quiet weekday. Stop. Look. Listen. Be careful.

(photos from Wikimedia Commons; click on the captions to see the originals)

Rocks That Glow in the Dark

Willemite-Calcite fluorescing, specimen from Franklin Mining District, Sussex County, NJ (photo from Wikimedia Commons)

24 March 2022

Because we humans can’t see ultraviolet light we miss the fact that some rocks glow in the dark after exposure to sunlight.

The glowing orange and green rock at top is a composite of willemite (normally brown glowing green) and calcite (normally white glowing orange). On display under normal light it is boring by comparison.

Willemite-Calcite in normal light, specimen from Franklin Mining District, Sussex County, NJ (photo from Wikimedia Commons)

Other rocks can glow, too. Did you know that about 30% of diamonds glow under ultraviolet light? 99% of them glow blue but a few glow white, yellow, green, or red as shown below. See the explanation at Diamond Pro.

Fluorescing diamonds from Russia (photo from Wikimedia Commons)
Fluorescing diamonds from Zaire (photo from Wikimedia Commons)

And here’s a rock called blueschist (benitoite-neptunite-joaquinite-natrolite) that is housed at the Carnegie Museum of Natural History. In black light it would stop me in my tracks.

Blueschist with fluorescing benitoite-neptunite-joaquinite-natrolite vein, Carnegie Museum of Natural History (photo from Wikimedia Commons)

Under normal display it is merely interesting.

Blueschist with benitoite-neptunite-joaquinite-natrolite under normal light, Carnegie Museum of Natural History (photo from Wikimedia Commons)

Birds can see ultraviolet light so they see these rocks in all their beauty. Alas we cannot without black light.

On Throw Back Thursday learn more about glowing rocks at:

(photos from Wikimedia Commons; click on the captions to see the originals)

Domesticated Before Chickens?

Domestic geese and goslings with caretaker (photo from Wikimedia Commons)

23 March 2022

Goose bones uncovered from a Stone Age village in eastern China indicate that geese may have been domesticated before chickens.

Researchers analyzed the size and chemical makeup of 232 goose bones and used carbon dating to determine they’re 7000 years old. A chemical analysis showed the birds drank nearby water, indicating they were all raised in the same location, and some bones came from baby geese that were too young to fly and must have hatched locally.

Science Magazine: Geese may have been the first domesticated birds

Chickens were domesticated 5,000 years ago so this finding upends the notion that they came first.

Who was domesticated before chickens?

Before agriculture began 10,000 years ago, humans were nomadic in their search for food. The first two animals to be domesticated — dogs and sheep — were easily nomadic as well.

Agriculture prompted humans to form permanent settlements, which led to a spurt of animal domestication to keep the meat supply nearby. Here’s the list from dogs to chickens.

Who was domesticated first?  

Dog15,000+ years ago

Sheep10,000 years ago
Pigeon10,000 years ago to 5,000 years ago
Cat9,500 years ago
Pig8,000 years ago

Cattle8,000 years ago
Goose7,000 years ago
Horse6,000 years ago
Chicken5,000 years ago

Quite a lot happened before chickens.

(photos from Wikimedia Commons; click on the images to see the originals)

Female Mallard Becoming Male

Intersex hen mallard, Duck Hollow, 20 March 2022 (photo by Michelle Kienholz)

22 March 2022

On Sunday at Duck Hollow we saw a female mallard with odd plumage. She was paired with a male mallard but she resembled a male in eclipse plumage. Was this duck a hybrid? Or was it something else?

Intersex hen mallard with her mate, Duck Hollow, 20 March 2022 (photo by Michelle Kienholz)

Michelle Kienholz was so intrigued that she took photos and sent them to the Duck ID group where she learned an amazing thing about female ducks. This odd mallard at Duck Hollow is an “intersex hen.” She is becoming male in a process called spontaneous sex reversal (SSR).

Unlike mammals whose sex chromosomes are XX in females and XY in males, female birds have WZ sex chromosomes and males have ZZ. This means that female birds have all the equipment they need to be female but if something suppresses the “W,” they are left with only “Z” and express as male. (Males cannot become female because they have no “W” at all.)

Female ducks are born with two ovaries but only one develops. The left ovary actively pumps out hormones to stifle the male genes, making the bird truly female. If a disease damages the only ovary and it stops producing hormones the female duck spontaneously turns into a male. Experiments have shown that the now-male duck is able to breed and fertilize eggs.

Because most ducks are sexually dimorphic a female with a dead ovary eventually looks male as well. The intersex hen at Duck Hollow is partway through her/his outward transformation, which is why she/he is in eclipse-like plumage.

Notice the clues in her/his feathers that indicate the transition:

  • tail feathers are black and curly white,
  • green feathers interspersed on head
  • breast is darkening (top photo)
  • color line between neck and breast is becoming white
Intersex hen: tail end is black with white feathers, green feathers on head (photo by Michelle Kienholz)
Intersex hen, color line between neck and breast is becoming white (photo by Michele Kienholz)

Read more about Spontaneous Sex Reversal in ducks and see a video in this BBC article: How Does a Duck Change Its Sex?

For more information on bird sex chromosomes see Anatomy: W and Z. For photos of eclipse plumage see Mallards in Eclipse. And here is an article about spontaneous sex reversal in chickens, a problem for chicken farmers.

(photos by Michelle Kienholz)