Last week’s Vermilion Flycatcher, the briefly famous female photographed at South Cape Beach in Mashpee, turned out to be a one-day wonder, as we birders say – she hasn’t been seen since. Beyond a wayward Western Kingbird that’s still hanging around Peterson Farm in Falmouth, it was a quiet week on the Cape for fall rarities. The Vineyard, on the other hand, sported out-of-range, birder-pleasing niceties like a Brown Pelican, maybe the same young bird that bopped around the region last month, a Western Tanager, and a Prothonotary Warbler.
But one need not fret over rare birds, or the lack thereof, in October, as plenty of exciting new arrivals are likely to be flitting about just about anywhere you go, especially on the tails of these first real cold fronts. For example, we should all take a moment to appreciate the thermoregulatory wonder that is a Golden-crowned Kinglet – these tiny, attractive songbirds of northern forests have flooded into the region in the last week. At just 3” to 4” they are smaller than some North American hummingbirds and weigh as much as two or three pennies but, improbably, can survive frigid northern winters with nights colder than 40 below.
This is incredible for several reasons. First, tiny things have a high surface-area to volume ratio, meaning they lose a lot of body heat when compare with larger things. But somehow these mighty mites keep the furnace stoked enough to maintain a 110-degree body temperature, even in cold northern winters. They do this without going into a torpor at night like hummingbirds do in cold weather or by supplementing their diet with fatty, high-calorie seeds like chickadees do – kinglets only eat insects, even in the dead of winter as far north as coastal Alaska.
Author and biologist Bernd Heinrich became obsessed with how Golden-crowned Kinglets survive the cold and so followed them around in the Maine woods, eventually discovering that several will huddle together on frigid nights, they puff up their feathers into an inch-thick down blanket, and they mostly eat caterpillars of a widespread moth called the one-spotted variant – these naked little caterpillars are somehow tough enough to overwinter on exposed tree bark, making them a critical food source for kinglets and other winter songbirds in the north, and making them an even more impressive survivor than the kinglets.
Golden-crowned Kinglets really are everywhere with trees right now and are worth a look with their greenish back and wings, bold facial markings, and that flashy namesake crown, bright yellow, overlain with red in the males. The problem is these hyper kinetic creatures don’t often stop long enough to grant a good look. And though they call almost constantly as they move through the trees, Golden-crowned Kinglets are basically a feathered hearing test – many can’t hear them at all. But if you can still hear in the 8 or 9 kilohertz range, listen for their endlessly repeated triplets of fast little notes. They won’t visit feeders, except a rare visit to a suet feeder, so you mostly have to look for them out in the real world.
I didn’t intend for the entire piece to be about Golden-crowned Kinglets when I started writing, but as you can see, these birds pack about ten pounds of interesting into that little 5-gram package. So your assignment this week is to somehow notice these frenetic little birds. They’re at their peak abundance right now, having just arrived in numbers from northern forests over the last week. You can find them in any kind of woods, even in dune thickets, but they especially like conifers, particularly planted spruces. One last tip for finding these guys: make sure to to swing by your audiologist and have him tune those hearing aids to that 8 kHz range, you’ll be hearing more kinglets and less people, which seems like a win-win to me.
