Weeping willows (Salix babylonica) are popular landscape trees that were brought here from Asia. They’re easy to notice at this time of year because their drooping stems turn yellow in very early spring. From a distance you see a splash of yellow.
Imported species, especially those from Europe, grew up in a steady climate with few spring surprises so they’re quick to bloom in the spring and late to drop their leaves in autumn.
Meanwhile our native trees are still brown, conservative about producing tender shoots because they know that volatile spring weather can bring a killing frost in April.
Are you tired of winter? Watch for the weeping willow’s hint of spring.
February is a great month for watching raptors in Pittsburgh. Peregrine falcons are courting and bald eagles are already nesting. This week was especially full of raptor news. Here are just four of our many pairs.
First things first: Peregrine falcons!
Peregrines love good weather — don’t we all — so they were particularly active on Tuesday February 20, a single sunny day in the midst of snow, sleet, rain and fog.
Tarentum Bridge Peregrines:
At Tarentum, Steve Gosser found the resident female peregrine perched on a lamppost. Though she isn’t banded she’s easy to recognize because her breast is very dotted. This is quite different from her mate who has an almost clear white breast and is banded Black/Green 48/BR (Westinghouse Bridge, 2014).
Above, she looks regal on the lamppost. Below, Steve whistled to attract her attention and she gave him the “Who’s whistling at me!?” look. Many of you saw this photo when I shared Steve’s post on Facebook. It’s the perfect Peregrine Attitude shot.
Neville Island Bridge Peregrines:
There was a lot of Peregrine Attitude at the Neville Island I-79 Bridge when Karen Lang and I stopped by on Tuesday.
We found the female in a tree, preening in the sun but it wasn’t long before the male flew in and mated with her. (Yes, my digiscoped photo is awful. )
Afterward it looked like the peregrines weren’t paying attention but the female was alert for trouble. She flew over our heads in pursuit of a raven, then perched on the topmost arch and the pair mated again. This is serious Peregrine Attitude, as in: “We own the place! There are two of us here!”
Minutes later the female pumped upriver to chase away an immature female peregrine. After the ladies flew out of sight, the male circled up and away as well.
I was able to see through my scope that the male is banded Black/Green, possibly the same male as in prior years: “Beau” Black/Green 05/S (Pitt, 2010). However I couldn’t see any bands on the female, no dark spot like the Black/Red bands on Magnum, the resident female of prior years. This female deserves another look. I wonder if Magnum is gone.
Cathedral of Learning Peregrines:
Courtship is underway for Hope and Terzo at the Cathedral of Learning. Yesterday, February 21, she called for him to bow with her at the nest. We can’t hear her but people inside the Cathedral of Learning probably did. She is one loud bird.
The pair bowed for less than half a minute and then they were gone.
Keep up with the Hays bald eagles at the Audubon Society of Western Pennsylvania’s Hays Bald Eaglecam.
(credits: Tarentum peregrine photos by Steve Gosser. Neville Island peregrine by Kate St. John. Cathedral of Learning peregrines from the National Aviary snapshot camera at Univ of Pittsburgh. Bald eagle photos from ASWP’s Hays bald eagle camera.)
The Shapes of Trees continues today with an Asian import.
Some Pittsburghers call this tree a sumac but it’s a case of mistaken identity. Sumacs are in the genus Rhus. This tree is an Ailanthus, specifically Ailanthus altissima. Its common names include Tree-of-Heaven as it is called in China, and “Tree From Hell” because it’s so invasive in North America.
Ailanthus has a unique shape in winter with sparse, thick, crooked branches in an open crown. They’re always reaching up.
The branches look crooked from a distance because the twigs are stout and blunt and the buds are large and alternate. Each bud changes the angle of the twig. A twig can be as fat as your finger.
Ailanthus grows easily in waste places. David Sibley writes in his Guide to Trees,
Trees have been known to sprout from roots 150 feet away from the original trunk and grow over 12 feet in a year.
You would not think that something this cute could be a problem but European rabbits (Oryctolagus cuniculus) have plagued Australia for 160 years. After a century of recurring population explosions (think “plagues of locusts”!) scientists found a virus that kills only European rabbits. They introduced it in 1950 and it worked amazingly well for a while but the rabbit and the virus both evolved. Here’s their story.
Introduced for hunting in Geelong, Australia in 1859, the European rabbit immediately went feral and the population went out of control. Without any predators they covered most of the continent by 1910.
Periodic population explosions, called rabbit plagues, became the norm. The rabbits eat everything. They devastate native plants, push out native animals, denude the countryside and cause dust bowls. In the photo below, at dusk, they are everywhere but probably not a plague yet since there’s still some grass.
Hunting and poisoning were ineffective.
Then in 1950 scientists found a virus in South America, called myxoma, that killed European rabbits. They released it in Australia (and in France) and it cut the rabbit population by 99%. Wow!
But a few rabbits lived and so did the virus. Science Magazine reports that “within a decade, rabbit numbers were on the rise again as some evolved resistance to this deadly infection and the virus itself became less deadly.”
This month, a new DNA study of both the rabbit and the virus shows that:
Rabbits on two continents evolved the same genetic changes to beat back the virus—before the virus itself changed and regained the upper hand. […and…] In the 1970s the virus developed a greater ability to suppress the rabbit’s immune responses. That change, as well as the natural emergence of another rabbit-killing virus, has caused populations to decline again.
When severe drought, high temperatures and failing infrastructure hit Kamfers Dam in Kimberley, South Africa, the lesser flamingo colony that nests there was forced to make a dreadful choice. The lake usually provides food and their island provides shelter but the water was gone. Incubating adults were dying of dehydration. If the colony stayed, all would die so they abandoned this year’s breeding attempt — eggs and chicks — to live and breed again.
Kamfers Dam is a privately owned dam just north of Kimberley, about halfway between Johannesburg and Cape Town, South Africa. The site was originally an ephemeral wetland but became a permanent lake thanks to runoff and treated wastewater from the town of Kimberley.
In 2006 people noticed that the lake attracted a Near Threatened species, lesser flamingos (Phoeniconaias minor), so they built an S-shaped breeding island for them (pin on map above). At the height of the breeding season it’s covered in tens of thousands of flamingos.
Kamfers Dam is one of only six lesser flamingo breeding sites in the world and an international birding hotspot … until this year.
In January, because of severe drought and high evaporation, a large part of the lake went dry. The lake level could not be restored by the water treatment plant because of their own failing infrastructure.
The National Aviary stepped up to help. Terry Grendzinski, Supervisor of Animal Collections and avian specialist, knows all about raising baby flamingos so she flew to the SANCCOB rescue center in Cape Town. In the photo below she feeds one of the rescued chicks while wearing pink sleeves and back gloves to mimic the appearance of the chick’s parents. Click here to watch a video of the feeding.
So far, so good. The chicks are growing, preening and sunning in their enclosure (video below). Some are already standing on one leg!
Thanks to this massive rescue effort, this year’s lesser flamingo breeding season at Kamfers Dam will have a silver lining. You can donate here at the National Aviary to help these baby flamingos.
(credits: rescued chick at top, Terry G feeding a chick, and video of chicks in blue enclosure courtesy of National Aviary. Map of Kamfers Dam embedded from Google Maps. Video and screenshot of rescue at the dam from Saam Staan Kimberley on Facebook. Click on the captions to see the originals)
The brahminy starling (Sturnia pagodarum) from the Indian subcontinent was named for his black crest because it resembles the sikha hairstyle worn by Brahmins. He looks like a Brahmin when his feathers are at rest (above).
However, he raises his head feathers frequently.
Watch his crest as he sings in this video.
He’s a pushy bird whose shape, behavior and song remind me of our European starlings (Sturnus vulgaris). He’s not in the same genus … but close.
Among the heroes of the peregrine falcon’s restoration in North America, Tom Cade was legendary. During his lifetime peregrines went from plentiful to nearly extinct. Today their population is healthy and growing, thanks in great part to Tom Cade’s efforts and dedication. He died this month at age 91.
Tom Cade was a falconer nearly all his life. He became hooked on peregrines at age 15 when one flew close overhead on its way to capturing prey. That was in the early 1940s when the peregrine population was still healthy in North America.
By the mid 1960s Dr. Cade was the head of Cornell Lab of Ornithology, the peregrine population was in free fall, and he could see it happening. The situation so alarming that he and other raptor experts were desperately trying to find out why before it was too late.
In 1965 they convened a conference about the peregrine’s decline at the University of Wisconsin, Madison that became the catalyst for peregrine recovery. At that point they knew the decline was due to DDT and dieldrin but they had no proof. (Proof came later from Derek Ratcliffe.) Meanwhile, agricultural experts argued it couldn’t be caused by pesticides; the pesticides were so useful.
In a 2015 video on the 50th anniversary of the Madison Conference, Tom Cade told how the conference changed the peregrines’ future. The transformational moment came when Jim Rice, a renowned falconer and naturalist from Pennsylvania, spoke nine words. It changed Tom Cade’s life. See him tell the story here.
After the conference Tom Cade was key in all that happened next, especially in shaping the captive breeding program and peregrine reintroduction. DDT and dieldrin were outlawed in the early 1970s. By 1999 peregrine falcons were plentiful enough in the western United States that they were removed from the Endangered Species List.
The weather this month has been up and down like a yo-yo: A low of 6oF on February 2, highs in the 50s and 60s for six days, then a low of 14oF on February 9. During those warm days the sap started running in the trees. I wouldn’t have noticed except …
On February 10 during a walk in Schenley Park I found flash-frozen sap on the damaged trees. At top, a fallen red oak made a red-orange waterfall. Below, a small amount of sap in a fungi-encrusted tree dripped like orange ribbons.
Sap runs and freezes inside healthy trees, too. We just can’t see it.
Many animals give gifts to members of their own species but crows and other corvids are the only ones known to give gifts to humans. As John Marzluff explains in the video, crows will do this for people who feed them a lot and pay attention to them, or even rescue them.
When I read about this several years ago in Marzluff’s book Gifts of the Crow, I briefly thought about trying to make friends with crows but decided it would be a difficult relationship. If your friendship with crows is based on food they remember your generosity and bring their friends. Lots of friends. They can be quite demanding and don’t understand if you stop. Not everyone appreciates this.
Gabi’s story made international news in February 2015 but we don’t hear about it anymore. Six months after this video was filmed two of Gabi’s neighbors sued, demanding $200,000 and a court order prohibiting the Mann family from putting out more than a 1/4 pound of bird food. It took a year to settle the lawsuit; the details were not made public.
Crows remember the faces of those who are mean to them and those who are especially kind. I’m sure that a few special crows remember Gabi.
Love is in the air at the Harmar bald eagle nest. Gina Gilmore saw lots of activity last weekend.
Sometimes the female calls for her mate (above). He flies in to see her and they mate (on 8 Feb).
… and mate again (on 10 Feb).
They’re getting ready to nest, though their first egg is at least a week away, maybe more.
The Harmar pair historically lays 10-18 days later than the Hays bald eagles whose first egg arrived this week on 12 Feb 2019 at 6:45pm. In 2015-2018, Harmar’s first egg was between February 20 and March 9.
This year there’s no camera on the new Harmar nest so we’ll have to watch the female’s behavior to know when her first egg arrives.
In the meantime love is in the air. Happy Valentine’s Day!