Sunday, January 24, 2016

The Specialized Sapsuckers

Alliteration, anyone?

Woodpeckers that comprise the genus Sphyrapicus are commonly known as "sapsuckers."  These four specialized species drill "sap wells," evenly spaced holes in trees; the sap of which attracts insects they forage upon.

There is an uncommon sapsucker, uncommon to our region, that is spending a third winter with us.


Red-naped Sapsucker (Sphyrapicus nuchalis)

On a stand of sizable sycamores, this Red-naped Sapsucker is spending a third winter (presumably the same individual).

Red-naped?  The nape is the back of the head and/or neck.

This photo shows the red patch of feathers on the back of this bird's head

That red-patch isn't always that conspicuous.  It can be smaller, far fainter, or through your binoculars all the bird is affording you to see is the following:



Sweet! Great looks! But..,
Where's the nape? I can't see the nape? What nape?
In our region, the de facto sapsucker is (S. ruber) "Red-breasted Sap-sucker." The red-breasted, for starters, has an almost entire red-head; which is helpful.

Sweet! Great looks! But..,
It isn't the neighborhood Red-breasted sapsucker.  The Williamson's (S. thyroideus) sapsucker has a nearly solid black head.

It leaves us with the question, "Is it a Yellow-bellied Sapsucker (S. varius) or red-naped?"  Both of which are rare birds for our area.  However, in some parts of the continent the two species' ranges overlap.
I happened to live for several years in such a place.

So back again, the hypothetical is: this all we are seeing..


We cannot see the back of its head.  We cannot see its nape.  However, you are rocking with views like this... if the bird stops drilling holes for a moment.

The above Red-naped Sapsucker (RNSA) image shows a helpful bit of diagnostic topography.  The red throat on an RNSA extends pretty much all the way to the white stripe that broadly crosses the side of the face.  The Yellow-bellied Sapsucker (YBSA) has a black border between the red and the white.

Another helpful tip, if you aren't seeing a red-enough nape, or seeing the nape at all on your bird; the back, the mantle.


Still, our bird, which has a nice conspicuous red-nape.  Let's pretend it does not.

The RNSA's back/mantle has far more black than the YBSA.  The RNSA has black down the center of its back, splitting two white lateral rows or columns.  The YBSA has a single broad whitish back, lending to less black on the "shoulders," the scapulars.

Yellow-bellied sapsuckers do wander in from time to time.  In our region, there was one in Aptos last year at a private residence.  Currently, one is being reported in Santa Clara County.

Years ago our red-breasted, the red-naped, and the yellow-bellied sapsucker used to be lumped into one species: Yellow-bellied.
These three are super-close cousins.  Hybridization occurs frequently. And in certain dark alleyways, there remains grumblings on DNA, and the splitting species from the one, etc.

The bird that's returned for another winter at Henry Cowell Redwoods State Park in Felton presents all the diagnostic marks to determine it as Red-naped Sapsucker.



Thank goodness.



No comments:

Post a Comment