The Wisconsin birding list discussed this a few years ago. They documented similar behaviors with finches (esp. goldfinches) and thistle. They speculated that the seeds are being treated at such high temperatures (so they don't reseed) that they're drying out and/or that the long import time is drying the seeds out. Apparently, thistle seeds have a short shelf life.
I don't know if their explanation is right. But I'm adding this because birders in at least one other state are noticing the same patterns. There is a juniper at the edge of my yard. Below it are all sorts of introduced plants that, I suspect, robins (and perhaps waxwings) have spread while visiting the juniper to eat her cones: a young Russian Olive, Poison Hemlock, and thistle. It's neat, though frustrating, to see how these plants cluster around a favored spot of songbirds. Meanwhile, I have several baby junipers growing around my yard, thanks, surely, to those very same songbirds. - Jared Del Rosso Centennial, CO On Tuesday, May 30, 2023 at 3:40:06 PM UTC-6 John Malenich wrote: > I've noticed the same thing with them completely refusing thistle starting > at about the same time (3-4 years ago) after many years of devouring > thistle with the same feeder set up with sunflower seed nearby. Now they > are only eating sunflower no matter how many times I put out fresh > thistle....about to give up on it. > > John Malenich > Boulder, CO > > On Monday, May 29, 2023 at 6:48:50 PM UTC-6 Chip Clouse wrote: > >> Hulled sunflower gives higher caloric value for less work as it doesn't >> have to be cracked to be eaten. I think your birds have just gotten >> smarter, that's all. >> >> Cheers, >> Chip Clouse >> Lakewood >> >> On Mon, May 29, 2023, 2:13 PM Jim Tyler <[email protected]> wrote: >> >>> Birders - >>> >>> I’ve noticed a change in Goldfinch (both American and Lesser) behavior >>> over the past 6 years or so. >>> >>> I live in Roxborough Village, and going back 5-6 years, we had a >>> dramatic increase in the numbers of Goldfinches. Two foot-tall mesh thistle >>> feeders would be covered with a dozen Goldfinches each, with easily a dozen >>> or more waiting to feed. It was normal for them to consume 1/2 to 2/3 of >>> the seed from each feeder daily. >>> >>> Local populations crashed roughly 3-4 years ago, with almost no >>> Goldfinches showing up at my feeders. Oddly, at that time, I noticed that >>> the remaining Goldfinches had gravitated to my (shelled) sunflower seed >>> feeders. This continued for a roughly 3 years, with only one or two >>> Goldfinches showing up at a time. >>> >>> So far, this seemed normal as populations shift, and Goldfinches are >>> known to eat sunflowers, but they were completely ignoring my thistle >>> feeders. >>> >>> This year has brought more Goldfinches - as many as 10 at a time - but >>> the unusual thing is that they ALL are eating sunflower seeds and ALL >>> ignoring my thistle feeders. >>> >>> I dumped all my older seed and have completely refilled my thistle >>> feeders twice, and have moved one to the front yard, but the Goldfinches >>> continue to eschew my thistle feeders and in both front and back yards now >>> exclusively eat sunflower seeds. >>> >>> At the same time, House Finches are also ignoring my thistle feeders. >>> >>> While it’s possible I’ve purchased a bad or old batch of thistle, I’d >>> like to think that the bird supply retailer I use hasn’t received bad seed. >>> >>> So my question to the group is whether anyone else is seeing Goldfinches >>> at their feeders refusing to eat thistle? >>> >>> Thanks! >>> >>> Jim Tyler >>> >>> -- >>> >> -- >>> You received this message because you are subscribed to the Google >>> Groups "Colorado Birds" group. >>> To post to this group, send email to [email protected] >>> For more options, visit this group at >>> http://groups.google.com/group/cobirds?hl=en?hl=en >>> * All posts should be signed with the poster's full name and city. >>> Include bird species and location in the subject line when appropriate >>> * Join Colorado Field Ornithologists https://cobirds.org/CFO/Membership/ >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Colorado Birds" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/cobirds/e95e7795-c4f8-42d5-6a96-98eedc5be7bb%40comcast.net >>> >>> <https://groups.google.com/d/msgid/cobirds/e95e7795-c4f8-42d5-6a96-98eedc5be7bb%40comcast.net?utm_medium=email&utm_source=footer> >>> . >>> >> -- -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/cobirds?hl=en?hl=en * All posts should be signed with the poster's full name and city. Include bird species and location in the subject line when appropriate * Join Colorado Field Ornithologists https://cobirds.org/CFO/Membership/ --- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/dea5f54b-1421-4d8e-881b-7eca63bd56d3n%40googlegroups.com.
