Talk about allergies! Oak tree pollen is finally diminishing in Pittsburgh, but grass pollen allergies are ramping up. I’m allergic to lawn grass. I feel it already.
A study last year explained why we suffer more in the 21st century. Pollen season is getting worse every year because climate change is lengthening the growing season and increasing pollen production.
“Plants that are grown in pollution-stressed situations are known to release more allergens,” says Elaine Fuertes, a research fellow at the National Heart and Lung Institute, Imperial College London.
Depending on the plant species, air pollutants can change the chemical composition of pollen, increasing the potency of pollen allergens and triggering stronger allergic reactions in people. …
…Air pollutants like particulate matter and nitrogen oxides may also make the exine — the outer coating of pollen grains — from some plant species more fragile and, therefore, more likely to rupture into smaller fragments that can penetrate deeper into the lungs.
BONUS FACTLET: While looking for lawn grass photos I learned that Pennsylvania’s most common lawn grass, Kentucky bluegrass (Poa pratensis), is not native to Kentucky nor to North America. Poa pratensis is from Europe, North Asia and the mountains of Algeria and Morocco.
Leaf-out reveals the browseline, Schenley Park, 5 May 2024 (photo by Kate St. John)
11 May 2024
This week I photographed a few puzzling objects for the record.
When I took a photo of Full Leaf trees in Schenley Park on 5 May I noticed something newly visible in the presence of leaves. Can you see it?
Look at the center of the photo where the path disappears in the distance. Above the path is a gap that allows you to see further under the trees. The gap flows to the right and follows the contour of the hillside. That’s the browseline, the cumulative effect of too many deer eating at the same location over and over.
I saw a native(!) honeysuckle this week. Pink with fused leaves, it’s called limber or glaucous honeysuckle (Lonicera dioica).
Limber or glaucous honeysuckle, Moraine State Park, 7 May 2024 (photo by Kate St. John)
Was this a cattle egret at Moraine State Park? If so it was a rare bird! Nope. It’s a white bag.
Cattle Egret at Moraine State Park? (photo by Kate St. John, 7 May 2024)
On 3 May a leaf-footed bug appeared to walk across the sky.
Leaf-footed bug walks across the sky, 3 May 2024 (photo by Kate St. John)
During the Pittsburgh Marathon Dippy the dinosaur watched near the halfway mark.
Dippy wears black and gold for the Pittsburgh Marathon, 5 May 2024 (photo by Kate St. John)
If you live in close contact with animals you get to know them well. Shepherds of small flocks develop an especially close relationship with their sheep because they tend them every day — and for 24 hours a day during lambing in early spring.
Paula Aarons, originally from Valencia PA, runs a small sheep farm in New Hampshire called the Dancing Pony Sheep Farm. Last month she appeared on Junction Fiber Mill‘s Millcast program to tell the story of her flock supporting each other and supporting her, their shepherd.
Our mutual friend Jeff Cieslak introduced her 15-minute video.
People: My friend Paula told this wonderful story about her sheep for a podcast. I watched it, and I wept a little, and now you, too, must weep.
Have you seen coils or fluttering tags on power lines? Not related to power transmission, these accessories are visual cues that alert birds to the presence of wires.
Bird diverters come in many shapes and have changed over the years as new products come to market and are approved by government agencies. California commissioned a 2008 study to evaluate the orange and fluorescent swinging tag below for use in the Sacramento Valley where hundreds of thousands of waterfowl spend the winter.
Red ball markers make power lines visible to airplane and helicopter pilots and are usually installed near airports and on long lines over rivers and canyons.
I know from personal experience (my career in Information Technology) that there is really no good time to do a server migration and it always takes longer than users want it to. Cornell Lab says they’re migrating 1.6 billion bird observations and that if it goes really well some services may be up late on 20 March.
During the outage eBird will still work on your mobile phone in offline mode. This feature was built into the app long ago because the best birds are far away from cell towers.
The eBird app works in offline mode
So hang tight while Cornell Lab data goes into hiding for two days.
While visiting southern Africa in January I was impressed at how large the continent is. Africa is huge – so big that the contiguous U.S. can fit inside it three times, as shown above.
For instance, the air distance from top to bottom of Africa – Tunis, Tunisia to Cape Town, South Africa – is farther than Seattle to Toyko.
During the Ice Age, the Pleistocene 2.58 million to 11,700 years ago, there was a lake 600 feet deep in Death Valley where Badwater Basin stands today. Named Lake Manly(*) by geologists, it disappeared 10,000 years ago.
Badwater Basin is 282 feet below sea level so any water that reaches it can only evaporate yet the evaporation rate is so high that the basin is a salt pan. Occasionally — decades apart — there’s enough rain to make a shallow lake.
In the past six months California has had two unusual rain events. On 20 August 2023 Hurricane Hilary dumped 2.2 inches and caused Lake Manly to re-form in place. (The deluge also closed the Death Valley National Park for two months.) Amazingly the lake persisted through the winter.
And then the Atmospheric River event of 4-7 February dumped 1.5 more inches of rain. Lake Manly grew to a depth of 1 to 2 feet so in mid-February the National Park Service opened it to kayaking.
The last time the lake formed, in 2005, it lasted only about a week. This time NPS estimates it’ll be gone — or at least too shallow for kayaks — by April.
So if you want to kayak in Death Valley, get out there now before Badwater Basin returns to normal.
This statue of Scottish explorer Dr. David Livingstone stands in Zimbabwe at the western end of Victoria Falls. After African independence, European monuments were removed and European towns renamed but Livingstone’s statue still stands, the falls still bear the name he gave them(2), and the nearest town across the river is Livingstone, Zambia.
Twenty years ago, two attempts were made to remove Livingstone’s statue but “resistance to the removals from the local community has ensured that Livingstone’s statue remains where it was first erected, gazing sternly out towards Devil’s Cataract.(1)”
Our Zimbabwean guide pointed to a word carved on the monument that is key to Livingstone’s legacy in Africa.
In America we think of Livingstone as a great explorer but in Africa it is his never-ending fight to end the slave trade that holds him in African hearts. Livingstone went to Africa as a Christian missionary doctor and fell in love with exploring, ultimately mapping three long journeys in southern and eastern Africa covering 40,000 miles(2).
During his second expedition to the Zambezi River (1858-1864) he witnessed the horrors of the East African Arab-Swahili slave trade and vowed to end it. Men, women and children were captured in the interior and marched to trading posts on the Indian Ocean coast, one of which was Zanzibar a British colony ruled by Arabs.
Livingstone reasoned that if he became famous for finding the source of the Nile he could influence the British government to end the slave trade so he returned to Africa in 1866 to accomplish both goals.
Five years later, in the absence of news, Livingstone was presumed dead or lost. Instead he was still exploring, very weak and sick with malaria and without quinine to treat it because someone stole his medical kit. Meanwhile he wrote letters to Britain describing the slave trade but the slavers were the only ones available to carry his letters to the coast. Knowing that Livingstone was against slavery, they delivered only one of his 44 letters.
Livingstone’s disappearance was such a great mystery that the New York Herald sent journalist Henry Morton Stanley to Africa where he caught up with Livingstone at Ujiji in October 1871 and said, “Dr. Livingstone, I presume.”
British reaction was swift but Livingstone did not live to see it. “One month after his death, Great Britain signed a treaty with Sultan Barghash of Zanzibar, halting the slave trade in that realm. The infamous slave market of Zanzibar was closed forever.(2)“
More than any of his contemporaries, Livingstone succeeded in seeing Africa through African eyes.
p.s. In the U.S. most of us don’t realize that the West African slave trade that our country participated in was not the only source of slaves. Britain outlawed the trans-Atlantic slave trade in 1807 but it continued elsewhere. For instance, Mauritania in West Africa did not impose penalties on its local slave trade until 2007. Today slavery persists in some parts of Africa. Read about Slavery in Contemporary Africa here.
(credits are in the captions) Footnotes on sources.
The weather is going to turn nasty tomorrow and very cold next week so it’s time to stay indoors and watch birds where it’s warm.
Tropical birds and feeder-hungry mammals visit the Panama Fruit Feeder Cam at Canopy Lodge. The black-crested jay, above, takes a look at a potential meal while a mother agouti, below, brings her cubs to the banquet. Agoutis show up in dark too.
Today I found an illustration that’s full of surprises showing six animals in the rearing up position. With two humans for scale the animals are: an African elephant, a gerenuk, and four Sauropoda dinosaurs: Diplodocus, Giraffatitan, Barosaurus, and Opisthocoelicaudia. The black and white dot on the elephant and dinosaurs indicates the center of mass (COM) for balance; the tiny black square is the location of the hip socket.
The elephant and gerenuk (giraffe gazelle) both rear up to reach food but for many decades the idea that Sauropods lifted themselves from the ground was considered scientifically inaccurate.
This 1907 illustration of Diplodocus by Charles Robert Knight is so noted on Wikimedia Commons.
The note says the picture is not factual because “Sauropods were terrestrial.”
Did Sauropods always keep all four feet on the ground? They ate tall plants, two examples of which still live today in California: coastal redwoods and giant sequoias. It makes sense they would have to rear up to reach them.
Sauropod necks and torsos are lightened because of an extensive air sac system which, combined with long, muscular, and dense tails, helps shift the centre of mass (COM) backwards, closer to the hip socket in some sauropod species.
Some sauropods have retroverted pelves which might have allowed the legs to maintain greater functionality when rearing.
[Bones in] the anterior part of the tail suggest flexibility, the tail being able to serve as a prop when in a tripodal posture.
The hip socket allowed for a large range of motion, more than needed for normal quadrupedal walking.
The wide strongly flared pelvis was thought to further aid stability in a tripodal posture.
Specifically for Dippy, “The Center of Mass (COM) of Diplodocus is estimated to be very close to the hip socket. This makes prolonged rearing possible and does not require much effort to do it. Combined with its long, massive tail acting as a prop, it was also very stable. Mallison found Diplodocus to be better adapted for rearing then an elephant.”
The description also points out that Giraffatitan, the second dino from the left, would have a hard time rearing. His COM was too far from his hip socket and his tail was short.
So it’s likely that Dippy reared up on his hind legs and could do so for hours while he browsed the trees like a deer.
