Monday, April 19, 2010

Yellow-Bellied Sapsuckers

After we checked the bluebird boxes in Maxville (9 eggs so far), we took the "scenic" route through the coulees along Kings Highway heading towards Durand.   At the little creek - about a mile from Stai Coulee Road - I spotted a woodpecker flying across the road.  I stopped, pulled out my binoculars and scanned the trees.  There it was - a Yellow-bellied Sapsucker.

I pulled out my iPod and thumbed my way through the playlists and clicked.  In seconds, I had the drum and call of this bird playing though the speakers of my Prius.  I watched as the bird alerted to the sounds coming from my car.  The bird looked, flew right at us and landed in a cedar to the right of us, then he flew over to the traffic sign by the creek.  He landed on the signpost, looked around and drummed on the metal sign.

He was joined almost immediately by a female.  We sat quietly and watched the two of them interact.

We first spotted Yellow-bellied Sapsuckers two weeks ago, over by the rifle range near Silver Birch County Park.  The only woodpecker in eastern North America that's completely migratory (some travel as far south as Panama), they have been spotted wintering in the Lower Chippewa River valley.  They're migrating through Wisconsin now - and we've been seeing them virtually everywhere.
According to scientists at the Boreal Songbird Initiative, more than 50% of the total population of Yellow-bellied Sapsuckers breed in the Boreal Ecoregion of Canada and Alaska.   Throughout their breeding range, they choose early successional trees  - the aspens, birch and maples - for nesting.

                                                          Yellow-bellied Sapsucker breeding range

Studies indicate a positive population trend for this species in Wisconsin - primarily in the north woods and along river valleys.   

How can they survive on a diet of watery sap?
The sap these birds are after is different from the sap "from the tree's "xylem") we tap and boil to make maple syrup.  These avian sap-tappers go after the difficult-to-access and more nutritious sugar-laden sap in the thin wall of the tree's "phloem." 

Which trees are favored? 
Not just sugar maples and birches.  I was surprised to find a study that reported the familiar rows of sap wells in nearly a 1,000 woody plant species.  (I always wondered why I keep seeing the distinctive rows of sapsucker holes on trees other than maples).

These birds defend their sap wells from other sapsuckers - and the other animals attracted to them, including other woodpeckers, warblers, hummingbirds, bats, squirrels and porcupines!

Sapsucker's diet however, is not comprised solely of sap.  They also eat arthropods - ants, caterpillars and bees.

You can attract Yellow-bellied Sapsuckers to your yard by putting out grape jelly and suet feeders.

No comments:

Post a Comment