Today the sun will pause at 11:19pm Eastern Time and begin to move north again — or so it will seem to us earthbound humans.
The far north will be dark but not inky black everywhere. At Kotzebue, Alaska, 26 miles north of the Arctic Circle, the sun will rise at 12:56pm and set 1 hour and 43 minutes later, similar to the solstice photo above, taken at Bering Land Bridge NP. Kotzebue is the furthest north I’ve ever been though I didn’t get off the plane..
Scene from the plane at Kotzebue, Alaska on the day before the summer solstice, 2019 (photo by Kate St. John)
Here in the Lower 48 we’ll have lingering sunsets …
Duck Hollow, where Nine Mile Run meets the Monongahela River, is a good place to find unusual birds in Pittsburgh. Just after Thanksgiving Robert Warnock saw a young peregrine falcon harassing the gulls and posted these photos in the Duck Hollow Facebook group.
When I saw the photos a few weeks later I was so excited. This peregrine is banded Black/Green with blue tape on the USFW band. Can we find out who it is? Unfortunately, additional zooming couldn’t make the bands readable.
In the next photo I briefly hoped the mark above the bird’s back was a MOTUS harness but Not! It’s a ripple on the water. Oh well.
As expected, the peregrine didn’t stick around but you never know when we might see it again. Watch for those distinctive white stripes on the head and the dark belly. By the time we see this bird again it may have grown back the missing tail feather(s).
p.s. Here’s the back story: When I first saw Warnock’s photos all the clues pointed to the 2019 MOTUS peregrine from Downtown Pittsburgh. I checked with Art McMorris, Patti Barber, and Dan Brauning at the PA Game Commission, but without band numbers none of us could be certain of the bird’s identity. To tantalize you, here’s a photo of Pittsburgh’s MOTUS peregrine in June 2019. What do you think?
MOTUS nanotagged juvenile peregrine, Downtown Pittsburgh at USX Tower, 19 June 2019 (photo by Jason Walkowski)
Crows on their way to roosting on Pitt’s campus, Nov 2016 (photo by Kate St. John)
If you live in Pittsburgh I need your help. Where are the crows sleeping?
On 28 December 2019, Claire Staples and I plan to count crows for the Pittsburgh Christmas Bird Count. In the past it’s been easy to find the winter flock. Our only challenge has been counting 10,000 to 20,000 crows.
This year I’m worried. Last evening I drove around Oakland at 8pm and couldn’t find a single crow. They aren’t in the trees near the Cathedral of Learning (Pitt is grateful!). They aren’t in lower Schenley Farms. They’re not at Flagstaff Hill or Schenley Drive or at CMU.
I know they’re in Pittsburgh. I’ve seen them streaming overhead at 4pm and counted 2,000 staging at Schenley Park. But they leave after dark. Where is the roost?
If you know where the crows are sleeping, please leave a comment and tell me where. (Here’s what a roost looks like, pictured in 2017.)
Crows roosting near Heinz Chapel in 2017 (photo by Kate St. John)
Even if you don’t know where they sleep, it helps to know where thousands of crows are flying at dusk and dawn. What direction are they going? Please leave a comment to let me know.
It would be a real shame if Claire and I can’t count the crows!
Photos are what you really need anyway. Include an object near the feather to give it a sense of scale (size). Remember the location and habitat where you found it so you know what species are possible. Now you’re ready to figure out whose feather it is.
First determine the feather type so you know where it came from on the bird’s body. At this point you don’t care about color.
In the wild you’re most likely to find tail, wing or contour feathers, the same ones you see on the bird. The descriptions below include parts of a feather vocabulary defined here.
Rectrix (tail): Tail feathers (plural:rectrices) have barbs of equal length on both sides of the vane. (red arrows)
Remige (wing): Wing feathers have short barbs on one side, long ones on the other. (yellow arrows short and long)
Contour feather: covers the body
Semiplume: insulation under the contour feathers
Down: the warmest insulation near the skin
Bristle: sensory vane near beak and eyes (unlikely to find)
Fitoplume: sensory vane on wings (unlikely to find)
Next, think of birds with colors and patterns at that location on the body.
For additional help use the U.S. Fish and Wildlife Feather Atlas ID Tool for North American birds. At the Feather Atlas you’ll need to know the feather’s size in centimeters before you begin.
Ready for a quiz?
A. The feathers shown above are from a great spotted woodpecker eaten by a predator in Germany. What body part did they come from?
B. Here are two feathers of North American backyard birds. It’s a little harder to tell what body part they came from. (Length: red=9-10cm, blue=12-14cm) What do you think? Can you identify the species?
Long-tailed ducks, common eiders and surf scoters eat crustaceans and mollusks that they pull from the ocean floor. Their populations are in steep decline, in part because hundreds of thousands of them die as bycatch in gillnets.
The diagram below shows a gillnet used for cod fishing in Newfoundland. Though no one fishes for cod anymore, gillnets are still used for other fish where ducks are diving.
Federal fishing laws solved the bycatch problem for dolphins and whales by requiring pingers to warn the mammals away. Fish can’t hear the pingers but dolphins can. Is there a sound that will work for ducks?
University of Delaware grad student Kate McGrew tested long-tailed ducks, common eiders and surf scoters and found out they can hear 1-3 kHz underwater.
Most robins move south in the fall but some remain north in large flocks that wander in search of abundant fruit. They choose Pittsburgh in December because we have lots of fruit on our native trees, ornamentals, invasive vines, and shrubs.
Oriental bittersweet, Pittsburgh (photo by Kate St. John)Bradford or Callery pear fruit, Pittsburgh, Nov 2012 (photo by Kate St. John)Ornamental fruit tree, Dec 2019 (photo by John English)
Hackberries, a native tree (photo by Kate St. John)
When the fruit is gone and the ground is frozen, the robins will leave. I expect that to happen in early January.
Though this arctic seabird doesn’t eat algae it will starve if marine algae is not abundant. On Throw Back Thursday we’ll learn more with the help of two vintage articles.
Dovekies eat small invertebrates and fish but the majority of their diet is made up of copepods. A single dovekie eats 60,000 of them per day. Quadrillions(*) fall prey to dovekies during the breeding season. So … What the heck is a copepod?
Copepods eat microscopic marine algae called phytoplankton that contain chlorophyll and need sunlight to live and grow. In the high arctic, the summer sun makes phytoplankton bloom, as seen below in the Barents Sea. It takes quadrillions phytoplankton to feed billions of copepods to feed the dovekies.
Phytoplankton is really tiny, so small that you need an electron microscope to see it. The Barents Sea bloom above is thought to be Emiliana huxleyi, shown below. The disks are made of calcium carbonate which is also the primary component of seashells. The calcium in phytoplankton makes its way up the food chain.
Thus if phytoplankton is scarce, copepods are scarce and the dovekies starve. That’s how a seabird relies on algae.
(photos from Wikimedia Commons; click on the captions to see the originals)
(*) How many copepods? Here’s a back of the napkin calculation: Suppose there are 50 million dovekies, each one eating 60,000 copepods/day. Dovekies live in their breeding range for four to six months, so there have to be quadrillions of copepods available during that period. Dovekies aren’t the only animal that eats copepods. The numbers are staggering! (My original calculation had a power-of-10 problem. See Tom Brown’s correction.)
