The Sunflower Hill Chronicles, Part 15: Fall 2022 Observations and Factoids
November 2, 2022
By Birgitta Jansen
The temperature is right around freezing. Since the early morning hours, barely visible dust-like snowflakes filled the air, obscuring mountains and continuing throughout the day. It was the first snow and early in the season. The lure of Sunflower Hill was irresistible.
The Hill was transformed. No wind. A substantial layer of snow absorbed all sound, creating a feeling of intimacy with place. The snow was heavy and wet as it amassed on every surface. Slender trunks of young trees were bending down, the weight too heavy to bear. Even the thinnest of grasses wore little white caps, bending their heads still crowded with seeds but offering no resistance to this greater power. The older Ponderosas and Doug Firs stood solid and undisturbed. During their lifetimes, so much longer than those of humans, they had learned about weather and seasons. They remembered and they knew how to survive until claimed by age or machine. The silence was absolute.
Letting the richness of this snow-soaked silence seep into my psyche, I wandered up Sunflower Hill Trail, where my gaze came to rest on the glistening white rugged slopes of the Rockies. But as soon as I came into the open space on The Hill, the sound of anonymous traffic on St Mary Lake Road carelessly intruded — this ceaseless language of the road, the friction of rubber on wet pavement, the deep rumble of large engines. We are such noisy creatures. Interesting how we seem to be quite unaware of how we dominate the world around us in so many ways, including making noise where ever we go.
The sun was struggling to make its presence known through the thick but ever-shifting layer of grey overcast, the continuous changes in light creating a kaleidoscope of moods when the sky darkened or shifted again to an opaque luminosity. I heard one raven call as I was leaving… but there was no response.
A few weeks later (November 13), I returned to The Hill. It was much colder now; there was just a hint of a breeze, and a light overcast allowed for a bit of sunshine to come peeking through. While ambling up on Duck Pond Trail I encountered a seriously motivated woodpecker beating an insistent rhythm. Bits of Ponderosa Pine bark flew in all directions. Moments later, the Ponderosa’s neighbor, a Doug Fir, was subjected to the same treatment.
I have often wondered how woodpeckers get by without weekly appointments with a chiropractor. So I decided it was time to check it out. Easy enough to do… but no, it was not. It got complicated.
Some scientists reported that woodpeckers have a special bone called the hyoid bone that wraps all the way around a woodpecker’s skull and acts as a sort of seatbelt for the bird’s skull and in this way protects the brain. The plate-like bones in the bird’s skull are also more flexible, which helps absorb or dissipate impacts. (1)
In another study (2) the adaptions such as specialized skull bones, neck muscles, beaks and tongue bones were seen as impact-absorbing in ways that are very different from those in other birds. The adaptations are viewed as essential for protecting the birds’ brains. These researchers also found that the skull bones have a different chemical composition and density. Okay, all of that seems to make sense.
However, a researcher at the University of Antwerp, Sam Van Wassenbergh, came to a different conclusion: woodpecker heads do not absorb shocks. They’re not built for that. (3) The explanation: When you use a hammer, you want to deliver a blow. Therefore, you do not use a hammer that has a built-in shock absorber because that would make your action quite ineffective. A woodpecker’s head is a rigid structure that has evolved to function like a hammer to maximize the kinetic energy delivered with each blow. According to Van Wassenbergh, woodpeckers also have smaller and lighter brains than humans, which greatly reduces the pressure they experience on impact. In fact, Van Wassenbergh pointed out to the article’s author that “this bird has gone through millions of years of trying to minimize shock absorption…” (3)
Regardless of the different findings, woodpeckers are remarkable birds. As they use their strong tail feathers and claws to keep their balance on trees, their heads move toward the bark at 23 feet (7 meters) per second. They can do this 20 times per second, seemingly with no ill effects. At the moment of impact, the head slows down at about 1,200 times the force of gravity. That’s astonishing. As you are sitting and reading this on your computer, you are experiencing around 1G (or one time the force of gravity). A ride in a rollercoaster would expose you to 3 to 4 Gs. A jet pilot (flying an F-16 or F-35) pulls 9 Gs — which is a punishing and barely tolerable force of over 2,000 pounds on the body. (4)
Meanwhile, the woodpecker that triggered this search for knowledge disregarded my patient presence, camera in hand, and simply flew off to vanish in distant foliage.
I carried on and spotted a few larches still aglow in their fall colors. Later I heard that Robyn Duncan, of Wildsight fame, had observed that, in all her years in Kimberley, she had never seen snow on larches that hadn’t yet dropped their needles. The branches of the cottonwoods and Douglas maples were barren, having dropped their leaves within the last few weeks.
Not long thereafter, I encountered a hiker who mentioned that he’d seen grizzly tracks on Powerline just west of Campground Trail. And thus it was that I made speedy tracks on Powerline to see if I could find them, and yes, there they were! I have heard that there is a large male that seems to reside further down St. Mary Lake Rd., so it could well be the same one. The prints were impressive. I’m glad I only encountered paw prints and not the critter himself.
All photos by Birgitta except where noted otherwise.
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