House Finches are small, common birds often seen on bird feeders and woodland edges throughout the U.S. I've seen 4 to 6 of them together at our front yard feeders. They are slowly becoming accustomed to my presence on the front porch and I've managed to capture a few good shots of them.
Adult male House Finches are rosy red around the face and upper breast, with streaky brown back, belly and tail. In flight, the red rump is conspicuous. Adult females are plain grayish-brown with thick, blurry streaks and an indistinctly marked face. The red of a male House Finch comes from pigments contained in its food during molt (birds can’t make bright red or yellow colors directly). So the more pigment in the food, the redder the male. This is why people sometimes see orange or yellowish male House Finches. Females prefer to mate with the reddest male they can find, perhaps raising the chances they get a capable mate who can do his part in feeding the nestlings.
House Finches eat almost exclusively plant materials, including seeds, buds and fruits. Wild foods include wild mustard seeds, knotweed, thistle, mulberry, poison oak, cactus, and many other species. In orchards, House Finches eat cherries, apricots, peaches, pears, plums, strawberries, blackberries, and figs. At feeders they eat black oil sunflower over the larger, striped sunflower seeds, millet, and milo.
A highly social bird, the House Finch is rarely seen alone outside of the breeding season, and may form flocks as large as several hundred birds. House Finches feed mainly on the ground or at feeders or fruiting trees. At rest, they commonly perch on the highest point available in a tree, and flocks often perch on power lines. During courtship, males sometimes feed females in a display that begins with the female gently pecking at his bill and fluttering her wings. The male simulates regurgitating food to the female several times before actually feeding her.
Information obtained from the Cornell Lab of Ornithology.