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.
His legend was created to fill a gap and now the legend is fading. What if Columbus never crossed the Atlantic? Here’s how things might have been different.
The coronavirus pandemic gives us an inkling of what it was like when Columbus and the Spanish explorers brought pandemic to this part of the world. It changed the western hemisphere.
Before Columbus, the human population in the Americas was larger than that of Europe. The landscape, animals and birds were balanced by the pressure of so many people living in North, Central and South America. When European explorers accidentally left behind pigs that carried human disease, native Americans encountered the free-range pigs, had no immunity and spread the plagues through human contact.
The Western Hemisphere suddenly lost 95% of its human population in only 150 years. Remove the keystone species and you get some pretty weird results. European settlers didn’t see the transformation so they thought what they found was normal including the endless forest, huge bison herds and billions of passenger pigeons.
Green sea turtles (Chelonia mydas, above) are endangered and olive ridley sea turtles (Lepidochelys olivacea, below) are vulnerable even though both have a wide distribution in the tropical oceans. The threats they face are caused by humans including boat strikes, nets, poaching of the adults and collecting their eggs.
Back in 2015 conservation scientist Kim Williams-Guillén came up with a way to protect turtle eggs by using GPS-equipped decoys. Her award-winning idea was tried recently in Costa Rica with the results published this month in Current Biology.
A team of scientists led by Helen Pheasey placed a decoy egg in each of 101 clutches of green sea and olive ridley turtles. 25 of the clutches were stolen by poachers. Five of the GPS eggs were taken for a ride. One traveled 85 miles. This diagram from Current Biology shows the decoys and the routes they traveled.
Revealing the trade routes is a step toward saving the turtles though not the silver bullet. Conservation laws and their enforcement can be ambiguous from country to country. As Science Magazine explains:
Ultimately, though, scientists and nonprofits are going to need to engage communities with local outreach and education programs to save sea turtles, Williams-Guillén says. “The real meat and potatoes of conservation isn’t going to come from deploying eggs.”
These arborvitae cones were on the ground at a pine siskin hotspot. Three stages are pictured: Top = Spent cones as much as one year old, Middle = Opened cones that were emptied by pine siskins, Bottom = a mix of closed, opened and spent cones.
The huge acorn crop in Schenley Park is attracting many blue jays, squirrels and chipmunks. Here’s what the ground looks like below the oaks at Bartlett Shelter.
In other delights October trees, sky and shadows are spectacular.
The most numerous wild bird on earth, estimated at 1.5 billion individuals, is the red-billed quelea (Quelea quelea) of sub-Saharan Africa. This very social weaver finch migrates and nests in flocks that number in millions.
When the flocks get going they resemble swarms of locusts.
Red-billed queleas eat mostly grain and seeds. As they feed on the ground the flock leapfrogs from back to front like a rolling cloud.
In Africa they are so well known as flocks that it’s hard to think of them as individuals. Two males are pictured above. Here’s a female.
This species is a major pest of cereal crops, and huge efforts have been expended by national and international agencies on lethal control and attempts to reduce population numbers by use of explosives, petrol bombs and aerial spraying of [organophosphate] avicides; in South Africa up to 21 million reported killed in a single month, with annual kill estimates of up to 180 million.
Control operations, however, probably do no more than replace naturally occurring mortality, and there is a significant adverse impact on other species, which are poisoned directly or die after eating dead queleas.
This year’s Winter Finch Forecast predicted that the pine siskins (Spinus pinus) of eastern Canada would move south this fall. Indeed they have. Friends started seeing them in backyards north of Pittsburgh in late September but I don’t have a backyard anymore. I live in a high-rise and thought I’d have to drive far away to see them. Not!
Yesterday afternoon Aidan Place shared a photo of a flock of 40 pine siskins bathing in the roof gutter outside his window in North Oakland. I rushed over to his street and there they were!
The flock had found a favorite food, the cones of northern white cedar (Thuja occidentalis) also called arborvitae, in front of Aidan’s apartment and in a long row near the parking lot across the street. Here are the cones they were eating.
The natural range of arborvitae (below) overlaps the breeding range of pine siskins so the birds probably felt like they’d found a taste of home.
The flock was easily startled by loud noises (cars, for instance) but tolerant if I stood quietly. I was able to take a very bad photo with my cellphone. The bird is the stripey thing in the middle of the picture with his head down. Yes, they are camouflaged.
If you have a backyard, put out nyjer seed to attract pine siskins and American goldfinches. Watch carefully. Siskins look a bit boring and are smaller than goldfinches as you can see in this 2018 photo by Lauri Shaffer.
If you don’t have a backyard, visit a cemetery and pause near the arborvitae trees. I bet you’ll find pine siskins.
The birds aren’t picky about being in the city as long as they find conifers — ornamental or otherwise.
(photos from Wikimedia Commons, Kate St. John and Lauri Shaffer)
Above and below, during their first visit on Monday 5 October at 4:53pm, Ecco scanned the sky to make sure Terzo wasn’t nearby. Then he and Morela locked gazes and nearly touched beaks. I can’t help but think Morela’s pair bond is stronger with Ecco.
On the second visit at 6:56pm Morela left before Ecco. He paused at the nest for a while.
Yesterday (Tuesday 6 October) Terzo visited for 6 minutes. He called to Morela but she did not appear on camera.
Ecco, Ecco, Terzo. I wonder when — or if — they’ll sort out which male owns the nest.
(snapshots from the National Aviary falconcam at Univ of Pittsburgh)