Siskins – plus one goldfinch –
December Bird of the Month:
When it rains siskins, it pours.
– David Fix and Andy Bezener,
Birds of Northern California
Most of the time, pine siskins are relatively uncommon at Bay Area bird feeders. But right now, they are being reported from what seems to be a majority of backyards. What's going on? Siskins periodically undertake what are known as irruptive migrations, during which they leave their primary range in Canada and the northern states and head south in huge numbers. The exact timing of these irruptions is not fully understood (they don't happen every year), but they are generally presumed to have some correlation with the abundance of their main food sources in the north, notably conifer seeds: in years of low seed production, therefore, the siskins head south until they find food. Which, in this case, may include your seed feeders.
Siskins on a hulled sunflower feeder. Note yellow in wings and tail, and typical belligerence. Photo by Putneypics.
- Pine siskins are streaky brown finches with yellow highlights in their wings and tail. As with our other finch species like house finches and goldfinches, siskins are small, flocking birds that eat mainly seeds and commonly visit feeders for sunflower or Nyjer seed.
- Siskins are most alike in plumage to female house finches, which are similarly brown and streaky. In addition to the yellow highlights in their wings and tails (which are rather subtle when birds are perched), notice their smaller overall size and thin pointy beak. Siskins are actually more closely related to goldfinches, whom they resemble more closely in shape and size—but goldfinches are not streaky!
- Siskins also have a distinctive call, a long upward-slurring zreeee that has a harsh buzzing quality that has been likened to watch-winding or tearing a piece of paper. They have other calls that are similar to other finches, but listen to this recording to practice picking out these zreeees from the background chatter (the first zreeee erupts after 10 seconds or so).
Siskins at your feeders
- Siskins mainly visit finch feeders filled with the tiny black seed called Nyjer or general purpose feeders offering sunflower. They particularly like hulled sunflower chips as found in our No-Mess Blend.
- As described above, most Bay Area residents are much more likely to see siskins in winter—and only some winters at that. But we do also have some siskins that stay here all year round and nest in the spring. In Marin, these resident siskins nest mainly in Douglas-Fir and other conifer forests, and so are concentrated in wooded areas such as around Inverness Ridge in Point Reyes.
- What people often note about siskins is their lively and rather combative demeanor. Big-time birder Pete Dunne described them as "a bird that makes up in sass and belligerence what it lacks in size. . . siskins seem to do everything just a little bit quicker than other species and make goldfinches seem sluggish and House Finch seem tethered."
- Unfortunately, pine siskins are the bird species most vulnerable to infection by salmonella bacteria. Although most birds currently being seen appear to be healthy, some sightings of sick birds are typical in these irruption years – these are highly social birds in a weakened, undernourished state freshly arrived from a thousand-mile, hunger-enforced exodus from their normal territory. The unfortunate reality of such migration events is that many birds will not survive the winter.
- As far as disease in your yard goes, what you should know is this: siskins with salmonella will typically appear puffed up, lethargic, and unusually tolerant of approach. If a bird just sits there, seemingly sleeping, while all others flee, salmonella is the likely cause. The bacteria is spread through bird droppings, so remember to keep your feeders clean, particularly if using tray feeders where droppings could contaminate the feeding area. The disease is also communicable to people and pets, so wash your hands carefully after handling feeders. If you see multiple sick siskins, take your seed feeders down for 1–2 weeks to reduce crowding while the infection moves through the flock. Then clean your feeders thoroughly and watch to see if sick birds reappear. (Note that hummingbird, suet, and peanut feeders are typically not used by siskins and can still be used even if you have to temporarily take down your seed feeders.) See our Backyard Bird Disease article for more.
Want to read more pages like this? See our Past Birds of the Month.