When you see a bird eating white berries from a hairy vine you might not realize it’s eating poison ivy. Birds are blissfully immune to the urushiol in poison ivy sap that gives us humans a nasty rash.
By late October poison ivy (Toxicodendron radicans) doesn’t look like the plant we’ve been avoiding all summer. The leaves are red or missing, the vine is exposed, and bunches of white berries hang from the branches. It’s easy for migrating yellow-rumped warblers (Setophaga coronata) to find the food they’re so fond of.
Back in March I canceled all my 2020 outings because of COVID-19. The disease has not disappeared — in fact it’s resurging now in the U.S. and Allegheny County — but we’ve learned more about how it spreads and the relative safety of being outdoors. Today I’m announcing my first and probably last outing of 2020 (winter is coming).
Next Sunday morning, 25 October 2020, I will hold an outing in Schenley Park with restrictions to keep us safe.
Participation will be limited. To join you must “register” by leaving a comment on this blog post (not in Facebook). I will respond via email & tell you where and when to meet.
Everyone must wear a mask that covers their nose and mouth.
We’ll social distance as we walk.
We’re sure to see fruits, seeds and fallen leaves. Birds may be few but there will certainly be acorns, chipmunks and blue jays. Will we find a white-throated sparrow? I hope so.
To prepare: WEAR A MASK. Dress for the weather and wear comfortable walking shoes. Bring binoculars and field guides if you have them.
Visit my Events page before you come in case of changes or cancellations.
What amazed me most about that discovery is that each dolphin waited for the other one to complete its speech before responding. I’m impressed that dolphins are polite in conversation.
In my family we all talk at the same time. Though we don’t always hear what the other person is saying, we don’t get offended if someone speaks while we speak. It was many years before I realized the behavior is impolite and I still struggle to wait and listen.
I should take a lesson from dolphins.
(photos from Wikimedia Commons; click on the captions to see the originals)
In eastern North America our chimney swifts (Chaetura pelagica) land every evening to roost in chimneys. In Eurasia and Africa the common swift (Apus apus) stays airborne for 10 months of the year!
No one knew this until Lund University in Sweden attached geolocator tracking devices to common swifts in 2015. When the swifts returned from their winter range in Africa the Swedes recaptured the tagged birds and found that most had not landed since they left!
Since common swifts spend so much time in the air and can live for 20 years an individual swift may fly 3 million miles in his lifetime. Wow.
(image from Wikimedia Commons; click on the caption to see the original)
In a normal year there’s practically no activity at the Cathedral of Learning peregrine nest from July until the next January so it’s safe for me to ignore the nestcam snapshots while the streaming falconcam is off. But not this year.
How do paleontologists find fossils? Better yet, how do they find small bits such as tiny dinosaur teeth?
In Wyoming they get help from ants.
In the video below Australian paleontologist Mikael Siversson (“Birds are dinosaurs”) describes a trip he and a colleague made to Wyoming dinosaur country in the late 1990s. The video starts with a picture of the Badlands as he begins to tell the story. Watch for four minutes — or longer if you want to learn about dinosaur teeth. It involves bathtubs.
(photo from Wikimedia Commons, screenshot from video; click on the captions to see the originals)
p.s. The toothy mouth pictured at top is the reconstructed skull of a Tyrannosaurus rex, a theropod ancestor of birds. Did birds have teeth? You bet!
Now that the breeding season is over birds have gathered for migration and the winter.
Early this week 50 common grackles leapfrogged over the trees and forest floor as they searched for food and bathed in Panther Hollow Run. (This photo gives you an idea of their abundance.)
Cedar waxwing numbers peaked in Schenley Park in early October when they devoured most of the porcelain berries. They’ll spend the winter further south, for instance in Memphis, Tennessee where this photo was taken.
Pine siskins were everywhere a couple of days ago. Are they still visiting your feeders? Where will they head next?
Starlings numbers are building in Pittsburgh as northern visitors arrive. Soon there will be thousands.
Crow numbers are building too. Last weekend I counted 2,400 but more arrived last night. Eventually the flock will look like this video from 2011. Where will they roost? Stay tuned.
Watch for spectacular flocks this fall. Let me know what you see.
(photos from Wikimedia Commons and Mr. T in DC, video by Sharon Leadbitter. Click the captions to see the originals)
Yesterday the news broke that a bar-tailed godwit fitted with a satellite tracking tag had flown non-stop over the Pacific Ocean from Alaska to New Zealand in 11 days. During his 7,500 mile trip he reached speeds of up to 55 miles an hour. He’s an amazing bird from an amazing subspecies.
Bar-tailed godwits (Limosa lapponica) breed in Scandinavia, Siberia and Alaska and spend the winter at shores from Europe to Africa, from southern Asia to New Zealand. Most travel over or near land (see map) but the Alaskan subspecies, Limosa lapponica baueri, flies down the center of the Pacific Ocean to New Zealand. According to Wikipedia, this subspecies makes “the longest known non-stop flight of any bird and the longest journey of any animal without feeding.”
Song sparrow with ancestor (photo by Frank Izaguirre)
Mourning dove with ancestors (photo by Frank Izaguirre)
Female northern cardinal with ancestor (photo by Frank Izaguirre)
Male northern cardinal with ancestors (photo by Frank Izaguirre)
We’ve known for a while that birds are descended from dinosaurs. In fact, paleontologist Mikael Siversson says, “Not only are birds descended from dinosaurs, but in fact birds are dinosaurs. They are highly specialized surviving dinosaurs.”
Of course modern birds have never met their long lost relatives so last Sunday Frank Izaguirre tweeted “A gift I recently gave myself was to put some dinos in the yard to facilitate this meeting of the ancestors.” They met below the bird feeder (photos above).
Bird-dinosaurs were lucky to survive the K-T extinction event that ended the Age of the Dinosaurs. Mammals survived, too, and in the absence of large dinosaur predators they took over.