On the wild side—September, 2012
by Tina Mitchell
Your first impression—a bundle of frenetic energy wrapped in a tiny, streaky brown body. Look more closely and you might spot splashes of yellow on the wings and tail—a Pine Siskin! Acrobatic, and nimble, sometimes even dangling upside down when feeding, these siskins seem to make the spritely Lesser Goldfinch look sloth-like and the House Finch seem to be clad in lead boots. The Pine Siskin’s song is a rapid series of stuttery, wheezy, raspy, call notes. During breeding season, the male adds a distinctive buzzy and ascending “zzzzrrrrreee!, referred to by some birders as the “zipper” call.
A Pine Siskin’s diet consists of small seeds of various conifers and some deciduous trees such as alder as well as seeds from a variety of annual plants, with a special penchant for the vast family of composites—e.g., sunflowers, daisies, and thistle. Oh, thistle. Pine Siskins love, love, love thistle seeds. If you wonder whether or not you have Pine Siskins in your area, just put up a thistle (sometimes called “nyjer”) feeder and stand back. If they’re around, they’ll find it and set up camp. And they’ll bring in other species that they tend to flock with, such as Lesser and American Goldfinches, to join in the feasting. Pine Siskins tend to be an irruptive species, especially in the winter—meaning, they move around rather erratically and don’t appear to have any strong investment in any wintering area. Some winters, they’re everywhere around here and they’ll drive you to the poor house as you try to keep your thistle feeders filled. Other winters, nary a one.
In the U.S., Pine Siskins primarily breed in the west, although they can wander to any state during the winter. In fact, Colorado is tied with Montana for the 2nd largest population of breeding siskins in the U.S., just behind Alaska (although Canada has by far the largest population). Beginning in mid- to late April, Pine Siskins typically nest in loose groups in our area, most commonly in our area in the pinyon/juniper habitat. The female builds a shallow, saucer-like nest well hidden in the needles and foliage; she usually lays 3 or 4 eggs, which hatch in about 13 days. Both parents feed nestlings by regurgitating a thick greenish paste into the nestling’s esophagus. (Yum.) The young leave the nest about 14-15 days after hatching, depending on their parents for another 3 weeks as they figure out how to live independently.
Recently moved to a new genus, the Pine Siskin is now named Spinus pinus. As noted in last month’s write-up about the siskin’s congener the Lesser Goldfinch, Spinus derives from the Greek word for a linnet (a small European finch that depends on flax seed, from which linen is made). The common name “siskin” has unclear origins, but some believe it’s an onomatopoeic representation of the siskin’s call. (Seems like a bit of a stretch to me…) Since other species of siskin are common in Europe, another possibility arises from words in Dutch (sidsken or sisgen) or Swedish (siska) for “chirper.” (Or you can just make up your own story. It’s just as likely to be true.) Both the species name (pinus) and the first part of its common name refer to the Pine Siskin’s alleged preference for breeding in pines. In Colorado, though, Pine Siskins have more generalized habitat preferences than their name suggests. Pine habitats make up only about 20% of the siskins’ habitats in our state. Siskins actually use spruce and fir forests much more frequently than they do pines. But taken together, all conifers composed 70% of all of the Pine Siskin’s Colorado breeding habitats. So perhaps the moniker Conifer Siskin would be more accurate.
Or maybe even the Thistle Siskin. Try saying THAT 5 times quickly!
You can read a bit more about this species and hear a clip of the “zipper” call here: http://wp.me/P16Ptu-bP.