A wise man once said: “The nature of a winter finch irruption, however, could mean a sizable flock of pine siskins can show up and empty out my Nyjer seed feeder at any moment.”

Just kidding. That was me writing two weeks ago about the hot start to the winter finch season. The wise man part is up for debate.

At the time of that writing, a female purple finch had been my only out-of-the-ordinary sighting at my feeding station. A week later a few fox sparrows showed up. I know fox sparrows are not finches, but they can fit loosely into the category of winter finches because of their sporadic visits to New England backyards.

Then last week, true to the sentence at the top of this column, the pine siskins showed up. It started out with two siskins sharing the tube feeder with a group of goldfinches. The next day, I counted three siskins. The third day, about 20 siskins showed up and occupied every perch on the tube feeder and a nearby hopper feeder. The spillover siskins searched the ground under the feeders for fallen seeds.

They didn’t exactly empty the feeders, however. They ate about half of the Nyjer, or thistle, seed in the large tube feeder and that’s about it. I’ve heard stories of great numbers of siskins staying put in backyards for extended periods and thinning out the wallet of the homeowner. Nyjer seed, their preferred food, is expensive stuff.

The big rush of siskins at my place lasted two days. The feeders were then void of siskins for a few days before about eight more showed up. That’s where I stand now at the time of this writing.

Pine siskins are the most common of the winter finches that irrupt from the north into New England and points south. An irruption is when a species visits an area in large numbers in sporadic years.

Siskins nest in Canada but may be found as far south as Florida and Central America during their irruption years. The pine cone seed crop determines when they head to points south, but it is unpredictable when the irruptions occur. That’s where programs such as Project FeederWatch, Great Backyard Bird Count, Christmas Bird Count, and eBird provide valuable data as scientists try to get a grasp on these irruptions.

Pine siskins are small, brown, heavily streaked birds, with yellow edging on their wings and tail feathers. The yellow edging is more prominent on the males. They somewhat resemble goldfinches, but siskins have a much more streaked appearance. Goldfinches are smoother. To further complicate the ID, siskins and goldfinches favor the same types of food and are likely to visit the same feeders. That can also be an advantage for birdwatchers as the birds often share a tube feeder, offering a side-by-side comparison. When seen next to each other, the differences are obvious.

So, the siskins showed up, finally. Now where are those evening grosbeaks I’ve been hearing so much about?