The beautiful but elusive evening grosbeak

Evening grosbeaks (Coccothraustes vespertinus) are Western birds and were once rare east of the Rocky Mountains. But during the late 1800s, each successive winter found them a little farther east. By 1910 they had reached Rhode Island. For many years evening grosbeaks enjoyed prosperity in the East. However, over the past 50 years evening grosbeak numbers have declined. Scientists have documented a 97 percent decline in Eastern populations. They mostly forage at the tops of tall coniferous trees looking for insects. They are particularly fond of spruce budworm, and the presence of many evening grosbeaks is often a harbinger of a spruce budworm outbreak. Grosbeaks are members of the finch family but are far heavier-bodied than most finches. The male is the more colorful of the sexes, with a dark head, yellow eye stripe, yellow chest and white wing patches on black wings. Females and juveniles are mostly gray with black and white wings. They also have a greenish bill, while the male’s bill is lighter colored.
Source:TERRY THOMAS For the Post Register, July 23, 2016
http://magicvalley.com/lifestyles/recreation/thomas-the-beautiful-but-e…