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Yellow-bellied Sapsuckers Drilling Wells & Lapping Sap

4-26-16 yellow-bellied sapsucker 191

Yellow-bellied Sapsuckers have returned and in between sending their Morse code messages, are drilling into over 1,000 species of woody plants to obtain sap.  At this time of year, sap wells are drilled into xylem tissues (transport water and nutrients from roots to branches) to feed on sap that is moving upward; after deciduous species leaf out, sap wells tap phloem tissues (transport sugars and other nutrients made in the leaves to other parts of the tree).  Unlike sap drawn from the xylem which contains from 2-3% sugar, phloem sap may contain 20-30% sugar.

Sapsucker tongues have a fringe of hair-like projections along the edges which enable the sapsucker to lap up the sap that accumulates in a well (“saplapper” would be a more accurate name for these woodpeckers).  Recently a female sapsucker landed on the trunk of a nearby Sugar Maple and tapped eight wells.  She then spent the better part of the afternoon inserting her brush-like tongue into the wells and drinking the sap that collected.  The entire time she was drinking sap, she was constantly (8 times per hour) evacuating a stream of clear liquid (as opposed to the typical uric acid excreted by birds).  Apparently much of what goes in must come out.

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10 responses

  1. Cordelia Merritt

    Oh Mary, This priceless.! How in the world do you have the patience to time the excretions. This is why I just hate the idea of deleting any of your posts. Hence my thousands in the inbox. Cordie

    April 25, 2016 at 9:35 am

    • Cordie, if all goes well, you may be able to throw all but the last few months out when Naturally Curious Day by Day is published in the fall 🙂

      April 25, 2016 at 10:39 am

  2. Elizabeth

    Ay-yup, any sugarer can tell you that an awful lot of liquid has to be removed to get the value out of maple sap. I’m glad we humans to use evaporators for the task.

    April 25, 2016 at 9:49 am

  3. mariagianferrari

    What a great photo!!

    April 25, 2016 at 10:23 am

  4. Jean Harrison

    What a shot. I didn’t know birds can excrete liquid urine. But it makes sense. Do hummingbirds do this also?
    I’m forwarding this to my brother and my son-out-law (they’re not married), both expert bird photographers.

    April 25, 2016 at 5:51 pm

  5. I have read that hummingbirds follow the sapsuckers to feed on the sap remains before there are many flowers to feed from.

    April 26, 2016 at 9:36 am

  6. While I was sitting next to our waterfall a couple days ago, a handsome male sapsucker flew to a tree quite close to me and slowly edged his way down to the rocks and took a bath. It’s moments like that that make life special.

    April 26, 2016 at 7:59 pm

  7. Sandy DeRosa

    Fascinating explanation. Thanks!

    May 17, 2016 at 2:36 pm

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