Featured Photo: A female Rufous Hummingbird approaches sap wells created by a Red-breasted Sapsucker in a willow tree trunk near a high meadow in the Umpqua Basin Cascades, western Oregon, June 24, 2019.
In modern human society, we have breweries, bars, pubs, and restaurants that offer their nectar to those that are thirsty or need some energy and nutrition. But in the wild, a chisel-billed bird releases a flow of thick sugary liquid from the inner bark (phloem) of trees and all forms of life come to sip from the fount. The creator of this source of nutrition in western Oregon is the Red-breasted Sapsucker. Additional species of sapsucker are found farther east in Oregon and across the continent where they too drill sap wells.
In case you are not familiar with Red-breasted Sapsuckers, let me introduce you to some I have encountered in recent years. Look carefully at the variation in the amount of white on the face/head, yellow on breast, and the distribution of white on the wings and back.
Red-breasted Sapsuckers make sap wells in many different species of tree, of many different sizes, and many different positions on the tree, from quite near the ground to quite high in a tree, and even out on some limbs. It is generally thought that the horizontal rows (across the diameter of the bole or branch) are evidence of exploratory drilling, while the vertical columns (parallel with the bole or branch) represent an upward extension once sap flow is found. Following is a sample from a single White Alder bole at Stewart Park in Roseburg, Oregon, showing the diversity of size, spacing, and orientation of holes made by a sapsucker on this one tree.
If you have not personally watched a sapsucker excavating these small holes in the bark of a tree, here is a wonderful 5-minute video by Abraham Finlay of a Red-breasted Sapsucker making and feeding from its sap wells in a cultivated red plum tree in his front yard in Roseburg, Oregon, November 11, 2022. If you’ve never watched a sapsucker up close, this is a fun watch. It’s also kind of fun to click on the video settings (the little gear or cog symbol) and change the playback speed to 0.25 to watch it in slow motion.
Above video by Abraham Finlay
The remainder of this post presents four different sap-well trees and examples of birds, a mammal, and an insect utilizing these trees, all in western Oregon.
TREE#1: The first set involves a small willow tree at a high elevation meadow in the Umpqua Basin Cascades, June 24, 2019. The first photos show views of the tree itself, followed by a Douglas’ Squirrel and then a female Rufous Hummingbird using the sap wells in this small tree.
Here is a close-up of the sap wells in this small willow tree.
Here is the same tree with a Douglas’ Squirrel using its tongue to lick out substance from the sap wells. Enlarge the photo by clicking on it and look closely for the pink of the tongue.
The following set of 6 photos show a female Rufous Hummingbird investigating and foraging from sap wells on all sides of this small willow tree.
TREE#2: On October 7, 2022, Abraham Finlay and I were birding out toward the South Umpqua river from Troost Street when we spotted a Red-breasted Sapsucker, then two, in a birch tree in a friend’s yard. The tree was about 2 ft in diameter at the base, but the sapsucker holes were concentrated in an area where the 18″-diameter bole split into 3 or more branches. As we watched these sapsuckers chasing each other around, we noticed a couple other species making use of the sap wells. One was an Anna’s Hummingbird, seen below hovering nearby between sips of sap. The sapsucker seemed aware but unconcerned.
Also at this sap well was a young Yellow-rumped Warbler that knew exactly where to find the energetic substance. Again, the sapsucker seemed willing to share.
TREE#3: As I was talking to Abraham about writing this blog post, he mentioned that he had seen a Ruby-crowned Kinglet using the sap wells at a cultivated red plum tree in his front yard. He set up his camera and was able to get these photos on November 11, 2022, showing the sapsucker and the kinglet at different times at the same sap wells. Click on the photos for a larger view.
Below is a close-up photo of some different sap wells on the same tree. Note how the lower wells are more “dry” while the upper wells are full of sap!
TREE#4: This last tree was a small, 3-inch diameter tree in the Umpqua Basin Cascades, June 11, 2019. I don’t recall and cannot discern the species of tree; possibly a Prunus species (cherry or plum). I wasn’t attracted to the tree, but to the butterfly (a type of Comma, Polygonia species). But as I watched the butterfly, I could see it putting its proboscis into the holes in this tree (enlarge the photo and look closely). In the field I noticed sapsucker holes on the tree and assumed the butterfly was foraging in them. However, in this photo it appears there may be both sapsucker holes and insect holes (and frass, shavings), so I am uncertain if the butterfly is obtaining sap or other moisture or minerals from within the sapsucker holes, insect holes, or both. Nevertheless, the butterfly was probing these holes, and if you look carefully you can see some dark staining on the bark from previous weeping or leaking of cambium fluid.
These observations represent a very small sample of the species and sizes of trees used by Red-breasted Sapsuckers and a very small sample of the various forms of life that benefit from the work of the sapsucker. Perhaps you will find an active sapsucker tree sometime soon, and with some patience make some observations of your own.
Special thanks to Abraham Finlay for his permission to use a few of his photos and video for this post and for his review of an initial draft.
This Post Has 8 Comments
Nice composition! “Sappies” (as I nickname them) are one of my favorite birds which routinely work the sizable Asian Vine Maple outside my living room window. One of the things I like most is that they are surprisingly tame. I can walk under that tree and they will pause to look at me, then go right back to drilling. Quite the opposite of the very shy Pileated WP.
Unfortunately, I’ve noticed on my country road that they seem not have learned sufficient wariness of speeding automobiles like some species have.
Excellent. Thanks
Thanks so much for preparing and sharing. Nice companion piece to “The Hole Story” which aired on PBS recently.
Enjoyed and learned from it all.
Thanks
Thank you for sharing.
Thank you so much for the wonderful tutorial. Very entertaining also.
Thank you for posting this!
Fascinating benefits for so many varied species from the work of just one family of bird.
Thank you for sharing your wonderful observations!