Saturday, March 14, 2015

Among the leaves and flowers


I had fun learning about Nuttall's Woodpeckers (Picoides nuttallii) today, 14 March 2015.  

I know some of you are familiar with this species, and some of you aren't.  If you have spent time with the similar Downy Woodpecker, some notable differences in Nuttall's include:

- black-and-white barring extending across the back (Downy's have a vertical white stripe)
- an extensive red patch on the back of the male's head (a male Downy's patch is smaller)
- some black spotting on the underparts (Downy's have none)


I watched this male Nuttall's Woodpecker foraging in an oak in Santa Rosa.  It spent most of its time among the new leaves and flowers.  I hadn't really watched a woodpecker do that before, so when I returned home, I read more about Nuttall's Woodpeckers and their feeding behavior.

It's true that Nuttall's Woodpeckers like oaks especially Live Oaks, Valley Oaks, and Blue Oaks.

But it turns out that they're known for being different — i.e., they don't often peck wood vigorously and forage deep below the bark like many other woodpeckers.  Instead they tap gently from the side, probe near the surface, and glean from the surface itself.  Miller and Bock (1972) also observed that they spend a lot of time scanning foliage and twigs.



Nuttall's Woodpeckers eat insects (e.g., beetles, ants, bugs, caterpillars, etc.), and they also eat "vegetable matter" (e.g., seeds, berries, and flower buds).

Now this gets tricky.  Was this woodpecker eating oak flowers, or insects attracted to the oak flowers and leaves...or both?

Only the woodpecker knows...



P.S.  I'm not sure how to identify all of the local oaks yet.  My guess is that this is a Valley Oak (Quercus lobata), but please let me know if that's wrong.

P.P.S.  Facts above from the Birds of North America account by Lowther (2000), and Miller, A.H. and C.E. Bock.  1972.  Natural history of the Nuttall Woodpecker at the Hastings Reservation.  Condor 74: 284-294. 
 

1 comment:

  1. It's pretty hard to identify oaks without a good look at the mature leaf and acorn. That one's either Q. lobata or Q. kelloggi, I think.

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