Visitors 117
Modified 23-Oct-21
Created 19-Oct-21
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Crossing the Lauriston driveway, on the way to Eagle Trail, we hear a loud drilling noise. Who is working so early on a Sunday morning? Don't folks know the rules for contractors in Portola Valley?? After a couple of seconds, the raucous noise stops. Starts again. Stops. Oh, this is not an electric jackhammer -- it is natural. A woodpecker! A huge woodpecker, and what's more, he has found a resonant log to amplify the sound.
I walk out to Alpine Road and look around. (Since I have only one working ear, I can't tell the direction sound is coming from.) As I am scanning the trees again and again, the intermittent sound pattern continuing, Helen finally comes out and points out the large woodpecker right there, on an electrical pole.
I stand there on upper Alpine Road for almost 20 minutes, trying different ways to photograph the rapid drumming of the backlit bird. When a passing driver asks me for my email (to share a photo, if I got one), the bird finishes drumming and flies off. I do hope I have some good photos. You can judge.
The next morning, returning from a walk up Windy Hill: woodpecking sounds again. This time, not so loud and resonant. More measured pecking, perhaps probing for insects and not signalling. After another search, we finally see the bird high in a California Bay, close to the bridge over Corte Madera Creek. I take a few more photos, this time obscured by foliage. I am not sure this was the same bird. On the one hand, Pileated Woodpeckers are rare hereabouts. On the other hand, yesterday's woodpecker might have been signaling -- perhaps hoping to form a breeding pair?
Challenge: can you tell the gender of either of these birds? Looking closely after searching the web, it appears to me as if the second one is a female. The first may be a male. From what I know of breeding pairs, they are probably of different genders. Leave a comment if you have an idea about this!
Here is a selection of my photos. Let me know if you want to see more, including a whole cycle of drumming. And read on to learn more about the Pileated Woodpecker, the “Good Lord Bird”, and the speed of woodpecker pecking.
The Pileated Woodpecker is the largest surviving woodpecker in the USA. Its larger cousin, the Ivory-billed Woodpecker or "Good Lord Bird" of the South, last reliably seen in 1944, was just declared extinct. Pileated Woodpeckers range across much of Canada, and east of the Mississippi in the US, with a few in a narrow band along our coast south from Canada, ending about here. (Also in the Sierras and near northern Idaho.) So while not endangered globally, they are pretty rare hereabouts.
Nerd alert: what follows is a calculation of the speed of the drumming, based on the fastest my camera can take a sequence of photos, and what I see in the photos. Read on only if you really care how fast the woodpecker pecks, and how I know.
How much wood would a woodpecker peck, when a woodpecker pecks on wood? A related question: How many pecks can a woodpecker peck, when a woodpecker pecks for a mate? How fast?
My camera was taking bursts of 15 photos/sec. In one sequence, on subsequent photos, I saw the bird extended with its beak near the hole, then retracted back, then extended again. If this was one pecking motion, I have seen 1/2 cycle per photo -- or 7 1/2 pecks per second. But if I have missed a whole peck, the bird could have pecked 1 1/2 times between two of my photos: 22 1/2 pecks per second. From watching, I suspect the former, 7 or 8 pecks per second. How fast can you tap a finger? The woodpecker has the advantage of evolution and practice, with possibly some springs to reuse the recoil energy.