Here’s a scary thought. If you’re an enemy to crows, they remember your face and harass you.
John Marzluff from the University of Washington shows how they remember their enemies in this clip from A Murder of Crows.
He investigated the phenomenon because he, like other crow researchers, was routinely harassed by crows after he captured and banded their young. Were they remembering his clothing? No, they remembered his face.
Perhaps you or a friend have experienced this too. For instance…
Mike Olaugh of Minneapolis left a comment on my blog about blue jays and added this note about crows. “The Crows … are ubiquitous no matter the conditions. We are near a cemetery and they have lived there for a century. I learned when I first moved here 20 years ago to leave them alone. They ganged up on my car and dropped on it en masse for a whole season. (I was trying to get them to stop roosting across the alley.)”
The crows recognized Mike and did something to drive him nuts until he left them alone.
Moral of the story: If you harass crows, you may have to wear a mask.
Happy Halloween. 😉
(YouTube video excerpt from PBS NATURE posted by Simon and Schuster as a promo for Marzluff and Angell’s 2012 book Gifts of the Crow)
There’s a bumper crop of black walnuts in my neighborhood this month, so many that they’ve stained the sidewalk black. They’re good to eat but how do you open them?
If you’re a human, you put on rubber gloves and safety glasses and hit the nuts with a hammer. The first whack cracks the greenish-yellow husk that stains everything black, hence the gloves.
The husk is the easy part. The shells are very, very hard to crack. Some people suggest using a vise instead of a hammer to open the nuts but no matter what you do pieces of shell go flying, hence the safety glasses.
If you’re a squirrel you don’t have tools but you do have teeth.
Donna Foyle watched a fox squirrel open a black walnut outside her window. The squirrels open peanuts in a flash but this black walnut took a long time.
The squirrel began by gnawing a hole on the side of the nut.
“He quickly gnawed the shell, turning it, gnawing many times, turning it, gnawing almost in continuous quick motion, turning it again. He never deliberately stopped gnawing to spit out the shredded shell,” wrote Donna.
You can see he made the “sawdust” fly. No goggles for him!
After 40 minutes he’d made real headway. The hole was a bowl from which he ate the nutmeat.
Did he save the rest for later?
The squirrels in my neighborhood are eating fewer and saving more, burying them in everyone’s mulch.
These very different leaves came from the same tree.
Sassafras turns red and yellow in the fall showing off its unlobed leaves, two-lobed “mittens” and three-lobed “paws.” All three shapes grow on the same tree including both right and left-handed mittens (I checked).
Sassafras (Sassafras albidum) is a medium-sized tree native to eastern North America from southern Maine to Florida to eastern Texas. In Pennsylvania it grows everywhere except on the central high plateau of the Northern Tier.
The tree’s roots, bark, shoots and fruit were used directly in many foods, drinks, perfumes and medicines (think “root beer”) until the essential oil, safrole, was discovered to be carcinogenic and outlawed by the FDA in 1960. Sassafras by-products can still be used in food and cosmetics as long as they’re certified safrole-free. Safrole is used in pesticides.
In Europe people plant sassafras as an ornamental for its aromatic scent and unusual leaves.
In a report last month in Current Biology researchers at University of Edinburgh and Swarthmore College analyzed 850 body features of 150 dinosaurs, then used statistical analysis to assemble a detailed family tree from dinosaurs to birds.
Interestingly, they found that the evolution of bird characteristics in dinosaurs was very gradual and non-linear. Features like feathers, wings and wishbones appeared in many species over tens of millions of years so there is no “missing link” dinosaur line to the first bird.
“This process was so gradual that if you traveled back in time to the Jurassic, you’d find that the earliest birds looked indistinguishable from many other dinosaurs,” said Swarthmore statistician Stephen Wang.
And then, 150 million years ago the bird skeleton came together and bang! there was an explosion in species from the one-of-a-kind hoatzin to more than 350 species of hummingbirds. According to Science Daily, this explosion “supports a controversial theory proposed in the 1940s that the emergence of new body shapes in groups of species could result in a surge in their evolution.”
Yesterday I photographed this half-inch-long moth at Harrison Hills County Park near Natrona Heights.
This morning I tried to identify it at butterfliesandmoths.org using the online photos. I was able to narrow my list to 20 possibilities out of more than 3,000 moths but none of them were correct when I compared closely.
Changing tactics I used the regional perspective: Which of my 20 possibilities were on the Allegheny County moth checklist? The checklist subtracted 10 and added four. However, my faith in that checklist was shattered when I discovered it’s missing Malacosoma americanum, the eastern tentworm moth, that Tom Pawlesh photographed in Allegheny County and posted on the website.
Not everyone is as enthusiastic about winter crows as I am. If you walk or park your car beneath the roosts you’re surely disgusted by the mess they make. What to do? Move the crows.
Central New York state has lots of experience with crow wrangling. At times Auburn has had 70,000 winter crows, more than two and a half times their human population of 28,000. Years of trial and error have shown that killing crows doesn’t work but moving them does.
So now, Central New York gets ready every autumn to move the crows to locations that aren’t so bothersome. This August 2012 video shows a seminar in Baldwinsville, 20 miles northeast of Auburn … as the crow flies.
This may look like an aspen forest but it’s a single tree, 80,000 years old.
Last week at the Botanical Society of Western Pennsylvania we were wowed by the news that this stand of quaking aspen, covering 106 acres near Utah’s Fish Lake, is a single “tree.” All the trunks are shoots from a single clonal root.
We learned this during Wil Taylor’s lecture on Jennings Prairie when he explained that aspen is threatening to take over Jennings. DCNR burns or cuts the prairie to keep it open but aspen love that treatment. They come back even stronger the next year with more shoots from the same root. In fact, fire and low rainfall are probably the reason why this huge aspen is doing so well in Utah.
Discovered by Burton V. Barnes in 1968 and nicknamed The Trembling Giant, Barnes used morphological clues to determine this Populus tremuloides was from one clonal root. In the 1990s Michael Grant studied it further and named it Pando. DNA proves it to be one plant hosting 40,000 stems and weighing 13 million pounds.
Pando’s given age is 80,000 years but that’s the conservative estimate. It may be as much as 1 million years old. No one knows for sure.
(photo in the public domain via Wikimedia Commons. Click on the image to see the original)