Photo: Pine Siskins, Judith Roan/Audubon Photography Awards
Pine Siskins Irruption in Northern Virginia
Jessica Bigger
A huge swath of Pine Siskins (Spinus pinus) has overtaken states across the U.S. this past fall through winter in search of food. This is by far the biggest irruption year ever recorded. Pine Siskins are abundant in Canada, less so in the U.S. Yet, sometimes a large population will move farther south in search of food when there are food shortages. This year, there have been fewer conifer seeds available in the boreal forest forcing Pine Siskins to fly south for food. Due to this irruption year, birders in Maryland and DC have enjoyed seeing huge flocks of Pine Siskins fluttering and chattering about.
Pine Siskins are small birds, similar in size to goldfinches, but have brown streaks with a dab of yellow on their wings. They also have a raspier song and call. They do tend to hang out in flocks while foraging for seeds. You will likely hear a flock before seeing them as they are constantly chatting, while foraging.
They prefer open conifer forests searching for pine cone seeds, but you will also find them fluttering about in deciduous forests, thickets and meadows. You’ll usually see them on the tips of conifer branches, occasionally hanging upside-down like chickadees rather than foraging on the ground. They are also big feeder birds in the winter preferring smaller seeds, like thistle and oil sunflower seeds. There has been a recent breakout of Salmonellosis in the local area, likely caused by contaminated bird feeders. So, local experts have advised people to pull down their feeders and disinfect them before rehanging them.
In the winter, flocks of Pine Siskins tend to be aggressive when competing for food. Some fearless ones will even hang out closer to larger birds at feeders eating the remaining seeds left behind.
These little guys are also more tolerant of extreme cold weather than other birds. They can survive in temperatures as low as minus 70 degrees Celsius. How do they do this? By increasing their metabolism to stay warm.
At this time the population is quite stable, but like most birds, Pine Siskin populations are still at risk due to habitat loss and salmonellosis outbreaks from contaminated feeders. Since they are attracted to minerals and salt, often found on roads, they are more likely to be hit by a car than other passerine species. Some experts have hypothesized that replanting conifer forests would make up for lost habitat. Climate change is also a concern. Like most birds, scientists predict as the Earth’s temperature increases, the population will shift farther north in Canada.
Sources:
https://www.allaboutbirds.org/guide/Pine_Siskin/overview
https://www.audubon.org/field-guide/bird/pine-siskin
https://www.audubon.org/news/-pine-siskin-finch-irruption-fall-2020
https://ebird.org/atlasmddc/news/november-2020-bird-of-the-month-pine-siskin