Who is that? If you are lucky, you may have seen an irregular visitor this winter. In several locations in our area, flocks of these yellow and black beauties have appeared. Evening Grosbeaks are a large, stocky finch with a thick, strong and pale bill, and a short notched tail. Our more common grosbeaks are summer visitors:  the Black-headed Grosbeak and in higher elevations, the Pine Grosbeak…cousins to the Evening Grosbeak, Evening Grosbeaks love seeds, berries and sapling buds. Sunflower seeds and platform feeders are their favorite, so keep your eyes peeled and maybe you’ll be lucky to catch one, or several!

What is an Irruption?

An irruption is the sudden change in the population density of an organism. When speaking of birds, irruptions refer to the movement of northern-wintering species to the south in years of low food availability. Irruptive species include redpolls, Evening Grosbeaks, and Red-breasted Nuthatches, among others. For Evening Grosbeaks, winter irruptions occur when pine cone crops in coniferous forests are poor and they move south to winter outside of their normal range. Theses irruptions usually occur every 2-3 years.

Fun Facts

Evening Grosbeaks like to eat wild cherries, but unlike other birds, they only eat the pits. After removing the fleshy fruit, they crush the slippery seeds with special pads in their “gross beak.” So favored are cherry pits that Evening Grosbeaks sometimes seek out the pits voided by American Robins. Evening Grosbeaks can break open seeds that require up to 125 pounds of pressure to crush. Evening Grosbeaks manipulate cherries in their beak to remove the outer skin and flesh, the remaining seed is then swallowed after it is cracked open with their beak. As with many finches, Evening Grosbeaks are attracted to natural salt and mineral sources.

The Evening Grosbeak is an irruptive migrant that makes irregular appearances at winter feeding stations throughout much of United States. The Evening Grosbeak was not commonly found east of the Rocky Mountains before the 1850’s. Winter irruptions now occur in all of the 48 contiguous states. The Evening Grosbeak was named in 1825 based on erroneous accounts that they became vocal and active only “at the approach of night.” This erroneous belief persisted for years, and the name is still a misnomer. Evening Grosbeaks seem to delight in snipping off the twigs of Sugar Maple trees and sipping the sweet sap.