Irruptive meets invasive

The Common Redpoll is an irruptive species: an arctic species that may or may not turn up locally in search of food in any particular year. This winter, they are here. They travel in flocks which descend on seeds. Locally, they seem to be partial to the common tansy, an invasive species.

The name, redpoll, refers to the red cap they sport — poll being an old word for head, as in “take a poll” (count heads), or a “poll tax” (a tax on each head). 

Flocks of the Common Redpoll are visiting the Lake this year. They fly frenetically between feeding on one bush of the (gone to seed) Common Tansy to the next.

While they are named for the red cap on their crowns, they also have distinctive black patterns on their faces that look like the ionizing radiation hazard trefoil with the bird’s bill poking through the centre. Here a redpoll is feasting on tansy seeds.

“I’m off to check out the seeds I see over there.”