A biting onshore wind brought tears to my eyes as I ran into it, and I upped my pace in an effort to keep the cold at tolerable levels. I had wanted to take advantage of the late-day light and go for a short run, as I had been indoors all afternoon.
I had also wanted to do a bit of bird-watching, so I’d brought my binoculars along. I could feel them gently thumping against my back as I loped down the beach.
I figured I’d be the only one crazy enough to be out there, as that day marked the beginning of the severe cold snap we had been experiencing. While the daytime temperature wasn’t yet as bad as it would become, the approaching dusk was causing it to fall like a stone.
As it was, I had plenty of company. Several people were out with their dogs, that seemed ecstatic and oblivious to the cold as they chased sticks, balls and each other. Their owners, meanwhile, snuggled deep beneath heavy coats, hats, hoods and scarves. I’m sure they thought I was crazy to be out there if I didn’t have a dog to exercise.
I had myself to exercise, though, and birds to see. It wasn’t long before I was stopping to look, sliding the binoculars from behind my back and focusing out into the cove. The first thing to come into focus — slowly, as the focus wheel of the glasses was sluggish because of the cold — was a pair of white-winged scoters.
While one of the scoters was busy diving for food — most likely blue mussels — the other carefully preened its feathers while floating passively on the surface. In the distance, I could see a female red-breasted merganser, also busy foraging. In the shallows near the beach, American black ducks foraged, upending in their comical fashion as they dabbled for food, possibly snails, amphipods and clam worms.
The ducks were so close I had excellent views as I watched them, marveling at the way they seemed so inured to their frigid element. Their feet paddled rapidly as they dabbled, and I could see the water beading up and rolling off their feathers when they surfaced.
With the approach of dusk, only the islands at the mouth of the bay remained bathed in light, their mantles of snow turning orange, then pink, with the setting of the sun. Closer to shore, in the shadow of the mainland, the ocean reflected the changing light with water the color of deep green anthracite. In the east, puffs of cumulous clouds flushed a light salmon and began fading to deep purple. With that, I realized it was time to head indoors. It was just too cold for comfort.
Thinking about the birds, I was humbled at the physiological adaptations that allowed them to survive in such severe conditions.
For starters, there is the amazing structure of their feathers. Made of keratin, strong yet flexible, they consist of tiny, innumerable projections that allow them to interlock tightly together. Small differences in these structures among birds, as well as how the feathers themselves are arranged, can provide waterproofing and buoyancy. There is also a substance secreted from a gland at the base of their tails that is used to maintain the integrity and health of the feathers — a rich oil of waxes, fatty acids, fat and water that basically cleans and conditions the feathers. Additionally, there are feathers called powderdowns, which continuously slough a powder of waterproofing keratin particles throughout the bird’s plumage.
Last but not least is the amazing system of thermal regulation in a bird’s legs, especially those of water birds. Very simply put, it consists of a network of intertwining arteries and veins (which facilitate a countercurrent heat exchange), as well as circulatory shunts, which can decrease the amount of heat loss through the feet by as much as 90 percent.
Pretty amazing what you’ll start pondering after a cold run on the beach.
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