The cardinal's beak tells the story

Beak of male cardinal

Have you ever tried to crack open a nut by chomping on it between your teeth? Northern Cardinals do this all the time with their cone-shaped beaks, as do sparrows, grosbeaks and finches.

These beaks have special features to make it easier: the edges of the lower beak fit into special groves in the upper beak. The bird uses its tongue to maneuver the seed into the groove to be crushed so the bird can eat the seed within.

Beaks meant for cracking seed usually are thicker and stronger than other beaks. The size is an indicator of what seed the bird eats. The goldfinch, with its smaller beak, prefers Nyjer seed while birds with larger beaks such as cardinals eat sunflower seeds. Look at the beaks of birds at the feeder and also look at what they are eating. While not all birds can crack sunflower shells, many more will eat sunflower chips (without shells).

About 90 percent of a cardinal's diet consists of seeds, as well as grains and fruits. It supplements these with insects, such as beetles, cicadas, grasshoppers and snails. During the summer, cardinals seem to prefer seeds that need husking, although they're less picky during the winter, when seed is scarce. At the feeder, you'll see cardinals eating mostly sunflower seeds (both black and striped sunflower seeds) and safflower seed. We've watched many cardinals on the patio break up peanuts and mash raisins to eat.