It was a treat to find two birds we never see in the Twin Cities at the feeders in Sax-Zim bog last weekend. Evening Grosbeaks and Pine Grosbeaks are the largest members of the finch family, and like other finches, the male is brightly colored and the female is somewhat drab in comparison.
Male (left) and female Evening Grosbeak
Male (top) and female Pine Grosbeak
Both species use their large, crushing bills to harvest seeds out of reach of the smaller finches in the winter, but the summer diets of both are quite varied.
Now that’s a big beak!
Evening Grosbeaks consume a lot of seeds in the winter, but they are largely insectivorous in the summer, especially when feeding chicks. They are a major predator of the spruce budworm pest. They are usually found in spruce-pine forests in southern Canada and the mountains of the western U.S. year-round.
Pine Grosbeaks prefer a diet of fruit with their seeds and might feast on crabapples in a residential yard, as well as the sunflower seeds at the feeder. They breed in the northern-most coniferous forests of Canada, feeding their chicks a mash of insect and vegetation.
The two species are not closely related, and the Pine Grosbeak is actually a circumpolar species, found in pine forests from Scandinavia to Eastern Asia, with its closest relatives being the European Bullfinches. In North America, both species respond to winter food shortages with irruptive behavior that might involve flying miles south of their breeding territories. Northern Minnesota is on the southern border of their winter range, so we felt lucky to see them.
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