Monday, January 24, dawned clear and cold, very cold. The thermometer on our Oak Bluffs porch, a sober and responsible thermometer not at all given to hyperbole, read six degrees below zero at sunrise. I believe the official Vineyard temperature, taken at the airport, missed dipping below zero by a couple of degrees. But even so, the morning will probably prove in retrospect to have been the coldest day of the winter, indeed the coldest one in several years.
I approached the day with a vague sense of awe, feeling like the rare visit to negative numbers would surely produce some epochal response in the natural world. My mind and senses were set to “observe” as I fired up the reluctant car and headed to work. And at first, the world did seem different. Backwaters, like the small salt pond on the Oak Bluffs side of the drawbridge, froze over solidly. More open bodies of water, like the outer harbor at Vineyard Haven, held enough heat so this brief flirtation with negative numbers couldn’t ice them over. But seawater sorbet splashed against the harbor’s lee shoreline, as light northwest wind imported a sample of the arctic from Canada.
Outside my office window, off of Lambert’s Cove Road, the world was quiet, with little wind and not a hint of birdsong. Binoculars in hand, I poked around the grounds. Rays from the rising sun hit the bark of a large oak tree outside my office window. A surprising knot of birds had gathered to glean what heat they could. In a large crotch about 30 feet off the ground, a group of bluebirds huddled, as many as 13 at one point, visible only as a jumble of eyes, beaks, and feathers of various shades of blue. The aggregation looked cozy but was far from amicable: the birds contended for the warmest position at the core of the group, and constant pecking and posturing resulted in a steady percolation of bird bodies through the heap.
Below the bluebirds, stuck to the branch, a group of woodpeckers likewise took advantage of the early morning sun. Well equipped to cling to vertical surfaces, woodpeckers have the knack of hooking their front toes into a tree trunk, settling the pointed tips of their stiff tail feathers onto the bark, and hanging from the resulting tripod to carry out whatever hunting or hammering is the order of the day. This time, the goal was energy efficiency: Once firmly mounted on the trunk, a yellow-bellied sapsucker and three northern flickers fluffed out their feathers and pulled their heads down between their shoulders. It looked like someone had nailed four disheveled, headless woodpeckers to the tree, to dry in the sun.
But as the sun strengthened, the day’s oddness faded. The bluebirds began sallying out from their jumble, dropping to the ground, finding bits of something to eat among the leaf litter, then flying back to the communal roost. But the sallies grew longer, more frequent, and the group gradually dispersed. The flickers, too, dropped to the ground, pecking the frozen surface and evidently finding something edible in the process. The sapsucker gradually roused itself, flew to another tree, and began poking its beak behind flakes of bark, no doubt fueling up on cocoons or dormant insects. Mid-morning, our usual mixed flock of chickadees, juncos, and tufted titmice passed through, feeding actively and chatting casually among themselves. All seemed normal and the sun was strong enough to melt the edges of ice patches.
A deep chill like that of the night of January 23 probably does kill some birds, and spring may reveal that some plants in my garden were not amused by the sudden transport of Zone 6 winter into Zone 7. (A sub-zero cold snap six years ago killed four of my five highly valued butterfly-bushes.) But virtually all of our native species, and most of the perennial species we’ve taken into cultivation on the Vineyard, are hardy enough to withstand brief periods below zero.
Most cold-blooded creatures, already dormant, don’t even notice the cold. Birds and mammals, while they may not like the chill, invoke a resourceful repertoire of behavior — basking, eating more, moving to a new location, or simply riding out the cold in a sheltered spot. But temperatures eventually rise, and normal life resumes.
Zero degrees on the Fahrenheit scale is one of those psychological barriers, like a Dow Jones average of 10,000, that seems to mean a lot more than it actually does. To be sure, wildlife responded to the extreme cold. But the impacts of this brief blast of cold, in the end, faded away before I could even fairly assess them. A notable event to a human Islander, a dip below zero barely tests the resilience of nature.