November is courtship time for one of the rarest seabirds on earth.
The Bermuda petrel (Pterodroma cahow) or cahow (pronounced ka-HOW) ranges across the Atlantic Ocean, returning to land only once a year to court and breed at Bermuda.
Cahows nest in dark burrows which they access only at night, so secretive that they were presumed extinct until 1951 when the last 17-18 pairs were discovered on an isolated Bermuda island.
Every year the odds are against an egg becoming an adult. However the birds’ long breeding lives, 30-40 years, ensure the species will survive as long as there are safe places to nest — and that’s the rub. Rats were eradicated from their breeding colonies but many of the burrows are on islands threatened by hurricanes and sea level rise.
Since 2001 the Cahow Recovery Program has been setting up safe breeding burrows on Nonsuch Island and translocating a few pre-fledgled birds to the burrows in hopes they will return there to breed when they reach maturity at 3-6 years of age. So far so good. There are now 15 pairs on Nonsuch, two of which use burrows equipped with live streaming Cahow cams under infrared light.
November is the time to watch the cameras at Cornell Lab’s Bermuda Petrel Cams. The pairs return to their burrows, prepare the nest, court and copulate. In the video below a pair touches beaks and preens in the courtship behavior called allopreening.
Watch the Cahow cams this month, especially at night. The birds are most active on the darkest nights of the New Moon.
Cahows leave their burrows in December, then the female returns in January to lay her single egg. If all goes well a chick will fledge in July.
The long process of creating and raising a single cahow chick has just begun.
p.s. Here’s an amazing fact about cahows: Notice that the birds have tube-like noses. These structures take the salt out of saltwater so they can drink it. They sneeze the salt out of their noses. There are more amazing cahow facts here.
Here’s an amazing bird unlike any other. Found in the Amazon and Orinoco Basins of South America, the pheasant-like hoatzin (pronounced Watson, Opisthocomus hoazin) eats leaves as 82% of its diet.
Leaves are really hard to digest so the bird has a huge crop that ferments the leaves and makes adult hoatzins smell like manure. The breath of mammal ruminants — cattle, sheep, goats, deer — may smell sweet. Not so with the hoatzin!
The hoatzin’s huge crop allows little room for flight muscles, so the bird is barely able to fly but that doesn’t matter. No one eats a bird that smells this bad.
Hoatzin nestlings don’t smell bad yet so they have to escape predators. During development in the egg, the young birds retain vestigial wing claws that all other birds lose during gestation. Before they can fly, hoatzin nestlings can climb back into their nests!
Read more about hoatzins and see video of a nestling crawling back into the nest at this vintage blog post: Watson, I Presume.
(photos from Wikimedia Commons; click on the captions to see the originals)
Now that the female peregrine, Morela, visits the Cathedral of Learning nest nearly every day you may be wondering how to identify her.
Here are her unique traits that you’ll see on camera, listed from easiest to hardest.
1. Morela has no bands on her legs. She often stands with her bare ankles showing.
2. All the normally white places on a peregrine — chest, face and cheeks — are peach-apricot on Morela. Even her belly beneath the stripes is peach-apricot, not white. This is noticeable in all photos.
3. Morela’s breast is clear with no spots or flecks of gray except at the edges (tiny flecks highlighted in photo below).
4. Peregrines have a broken necklace of charcoal gray that forms a frame on their cheeks below the malar stripe. Morela’s necklace is very wide when she turns her head, especially the necklace on her left side (necklace highlighted in photo below).
Morela shares some traits with other peregrines:
Morela is much larger than Terzo. This is a female trait in peregrines.
Morela’s forehead is pale where it meets her beak. Terzo has this trait, too, but Hope did not.
Morela’s head and nape are quite dark. So are Terzo’s.
There is very little color contrast between Morela’s head and back. This is typically a female trait in peregrines. Terzo has much more contrast — dark head, light gray back.
For comparison on camera here are two photos of Terzo in 2016 and 2017. Notice how white he is!
Lichens are two organisms that operate as one, a symbiotic partnership of a fungus with a green or blue-green algae (sometimes all three). The algae’s photosynthesis feeds the fungus. The fungus gathers and retains water and nutrients and protects the algae.
Those that grow on trees are epiphytes, totally dependent on the surrounding air and precipitation for their nutrition. As they take in air, their tissues absorb suspended elements in concentrations that mimic the air quality.
Lichens can thrive in some of the harshest habitats on earth but epiphytes can’t live in the presence of air pollution, so we were really surprised to find them on our Duck Hollow walk on 29 October 2019 when the air smelled of rotten eggs.
The smell is hydrogen sulfide from US Steel’s Clairton Coke Works, 8 miles away. On cold calm days the pollution creeps up the Mon Valley and blankets Pittsburgh’s East End, a reminder of Pittsburgh’s Smoky City days.
The pollution happens all too frequently, as shown in these screenshots from SmellPGH.org on 28 and 29 Oct 2019. (SmellPGH is a crowd-sourced app for reporting air pollution smells. Many dark red triangles mean the air smelled really bad that day. Click here for more info.)
We can smell hydrogen sulfide but not two dangerous air pollutants that travel with it: sulfur dioxide and particulate. Fructose lichens — the kind that stand out from the branch like those shown above — cannot survive in the presence of sulfur dioxide.
We were amazed. What have we here?
(photos by John Bauman, screenshots from SmellPGH.org; click on the captions to see the SmellPGH website)
Insects that disappeared in the cold came out again during last week’s warm weather. On Wednesday I found a western conifer-seed bug on my front porch.
Formerly restricted to the western U.S., the western conifer-seed bug (Leptoglossus occidentalis, WCSB) has spread across North America, to Europe and South America. At 1/2 to 3/4 inches this “true bug” sucks the sap of developing pine cones and the pulp of pine seeds.
On Friday afternoon, 1 November 2019, Terzo called to his new mate Morela to court with him at the Cathedral of Learning peregrine nest, “Come bow with me!”
Morela arrived immediately and became so wrapped up in courtship that she didn’t realize she was crowding Terzo into the back of the box. When he had no room to bow, Terzo stopped courting and left the nest.
Morela turned and called, “Come back!”
This was a brief courtship display even though it may look as if Terzo was running away. How do we know it wasn’t aggression? Here’s the difference between courtship and a fight.
In courtship you will see two birds, one much larger than the other, bowing and “ee-chupping” in squeaky voices. This is a very ritualized Ledge Display with a pattern of who-does-what: the male arrives and leaves first; they bow and ee-chupp; the female stays after he leaves. The ritual steps of the Ledge Display are described at:Familiarities On The Cliff.
I wish we’d stop turning the clocks back and forth. The sign in the photo above, behind the Kaufmann’s Clock in Downtown Pittsburgh, seems to agree.
p.s. The Kaufmann’s Clock at Fifth & Smithfield is a well known meeting place with a long history. My favorite story is the time in 1983 when Pittsburgh City Councilwoman Michelle Madoff challenged Council President Eugene “Jeep” DePasquale to meet her under the clock and make good on his promise to kiss her “you-know-what” after a tax she proposed raised more than the $20 he believed possible. Michelle waited under the clock with a stuffed donkey (a.k.a. ass) for him to kiss. Jeep never showed up.
(photo from Wikimedia Commons; click on the caption to see the original)
Just before 4pm Morela jumped into the nest and called to another peregrine. The male stayed off-screen for a minute, then jumped down to bow with her.
The male she’s been courting is Terzo!
Terzo has been the resident male peregrine at Pitt since his arrival in March 2016. I recognized him on camera by the unique heart-shaped white patch on the left side of his face and his black/red color band. No, I couldn’t read his band numbers in the video (Terzo is Black/Red N/29) but I believe he’s the only male peregrine in the world with that face pattern + Black/Red bands.
So now we know that the peregrine couple at the Cathedral of Learning is Morela & Terzo. For the first time in years I’m excited about the upcoming nesting season. Courtship will intensify in January. Egg laying is due in mid to late March.
If you’re wondering whether the crows would return to the University of Pittsburgh campus this winter, I have news. The murder is back, but only after dark. (*)
Late Monday afternoon, 28 October, I waited until sunset near the Cathedral of Learning for the peregrines to return for the night. The falcons slipped by unnoticed but as I walked to my car a huge flock of crows arrived. They were shouting!
The vanguard aimed for the trees on Forbes Avenue …
… then burst into the sky, wheeled around, and flew to Fifth Avenue.
By the time I drove past Heinz Chapel hundreds of crows were crossing the dark sky above Fifth Avenue near Clapp Hall. My windshield acquired “spots” as I passed beneath them.
This week most people won’t notice the crows because they arrive after everyone’s left Oakland for home.
Not so next Monday. After we turn the clocks back, sunset will be at 5:13pm and the crows will arrive during rush hour.