SCOTT SHALAWAY Eureka! Juncos discover nyjer

While collecting data for last month's Great Backyard Bird Count, one of the citizen science projects sponsored by Cornell's Lab of Ornithology, I observed juncos perched on a tube feeder eating nyjer (also called thistle). Having never seen that before, I mentioned the observation in last week's column and asked if readers had ever seen juncos eating nyjer.
What a response! In just four days I received more than 50 e-mails, letters and phone calls from readers who've noticed the same thing. Some said their juncos were cleaning up the nyjer that fell to the ground beneath elevated feeders. That didn't surprise me because juncos are normally ground feeders and most reference books include spilled nyjer as a possible junco food.
What did surprise me was that more than 75 percent of the respondents reported they had seen juncos using hanging tube feeders filled with nyjer.
Reader response
Here's a sample of the comments I received:
"I have a junco that has recently begun using my nyjer feeder. I've been feeding birds for years, and I've never seen this before." -- Ron Varner, Clearfield, Pa.
"My husband and I regularly see juncos at our raised finch feeder." -- Diane Price, Ellsworth, Ohio
"This is the first winter that we have seen juncos using our finch feeder. My husband and I thought this was very unusual." -- Annie Davis, Gap Mills, W.Va.
"I often see junco activity at my thistle feeder, not only this year, but in years past as well." -- Paul Brown, western Pa.
"I see them perched on my tube feeders all winter long." -- Bev Hobart, Poland, Ohio
"I regularly see juncos using a finch feeder filled with nyjer seeds. I didn't think this was unusual until I read your column." -- Linda Vance, Weston, W.Va.
"The juncos that visit my property regularly dine on nyjer seed at a tube feeder. I have observed this for the past two or three winters." -- Phyllis Martinek, Robinson Township, Pa.
"I have two finch feeders filled with nyjer seed, and juncos eat from them daily." -- J.R. Carnahan, eastern Ohio
Research
This news sent me to my library where I searched my backyard birding books, including one I've written, for information on juncos using finch feeders. I found none. So I called Dr. David Bonter, Leader of Project FeederWatch at the Lab of Ornithology. If anyone had heard of juncos using tube feeders, it would be him. He hadn't.
"Although we don't ask for the type of feeders birds use when our volunteers report their results," he explained, "I don't recall ever hearing of juncos on tube feeders. They typically use platform feeders or feed on the ground."
Clearly, juncos are considered ground feeders that occasionally take nyjer seeds that have fallen to the ground. But just as clearly, at least some juncos have modified their feeding habits. This observation prompted two western Pennsylvania birders to ask some interesting questions.
Pat Lynch of Wexford wonders, "Could their eating from tube feeders be an example of an evolving feeding practice?" And Bob Shoemaker of Murraysville asks, "Could we be seeing a behavior modification?"
Shoemaker answered his own question when he added, "Perhaps some juncos are adapting their diet to accommodate a new and easy food source."
Perhaps Shoemaker got it right. Ground feeders face a foraging challenge whenever it snows. Digging through an inch or two of snow may be manageable, but when heavier snow or ice covers the ground, adaptable individuals that can take advantage of foods that are easier to find may fare better than those searching for food in deep snow. It's really not that big a leap -- juncos perch readily on small twigs and branches, so discovering how to use a small perch on a finch tube may be a natural example of "Eureka!" learning.
This is what citizen science is all about -- observe, think and question. Then graduate students, guided by more experienced scientists, focus on the most interesting questions and test the possibilities.
sshalaway@aol.com