I had to look them up to be sure, but yes, these smallish, streaky-brown birds with flashes of bright yellow on tail and wing feathers that were flocking into my garden were Pine Siskins. I had not had them at my feeder for quite a while. They are lively! While confirming their identity, I learned that they are a type of finch, albeit smaller with a finer pointed beak. They adore thistle seed or small seeds like millet and acrobatically hung off my clumps of untrimmed flower stalks gleaning seeds, saved for just such a purpose. They appeared voracious.
Siskins are noted for their flocking behavior and for mobbing feeders. Some writers called them gregarious, while others shaded more to “aggressive” or “domineering.” Other feeder birds might agree. When Siskins move in, your chickadees and nuthatches are sidelined. But it seemed only momentary at my house. Siskins breezed in, partied, and left for new places; maybe I didn’t have their preferred foods. They can’t handle sunflower seeds still in the shell and are peckish about suet, my main offerings. I tried to capture them in photos but they swished around too rapidly to have more than blurry images.
They began, though, to show up on neighborhood postings and in anxious emails and message boards. All that close flocking and eating and general congregating—just like we humans used to do in pre-Covid times and now should not—can lead to tragedy. First there was excitement and wonder at the arrival of this northern bird from the conifer forests and mixed boreal woodlands of Canada, identified as an irruption from their normal migration pattern due to food shortages in their winter range. But it soon turned to dismay when more and more sick and dying birds were discovered at feeders and in gardens. The close flocking and feeding behavior that draws our attention facilitates the spread of salmonella bacteria that can contaminate feeders, birdbaths, and water dishes and be passed bird to bird. (Humans and pets can be impacted too. Wear gloves, wash your hands thoroughly and clean areas frequented by birds.)
Sick birds are said to be lethargic and appear tame—or at least indifferent to human approach. They have fluffed up feathers, perhaps swollen eyes and an unnatural stillness. Besides being careful about your own exposure, seeing birds in this condition signals that you need to take down your own feeders and dishes and clean everything with a mix of hot soapy water rinsed with bleach water. See here for exact instructions: https://wdfw.wa.gov/news/help-protect-wild-birds-deadly-salmonellosis And then retire your feeders for a week or more. Some advice recommends not putting out feeders again until sometime next month to be sure the Siskins have moved on and the danger has abated.
It was a melancholy sight to see a line of Bushtits clinging to the dangling empty string from my feeder. Where were the goods? It’s been very quiet for days now. I rejoiced to see a few juncos scrambling around under the ferns and in drifts of old leaves the other day. And the hummingbirds are as territorial as ever; their feeder is entirely their own and not endangered. How I miss “my” birds! But I have to remember it’s not about me, but their health and lives. And take the long view.
To learn more about Pine Siskins in general and about the meaning of irruptions, see here: https://www.audubon.org/news/-pine-siskin-finch-irruption-fall-2020
And here, at the Cornell Lab of Ornithology for more species information and a great map showing Siskin territory and what is impacting their normal range of habitation: https://www.allaboutbirds.org/guide/Pine_Siskin/media-browser-overview/67276581