Peanuts are like a secret weapon for people who love feeding birds. Your feathered friends will go nuts for the fat- and protein-packed treat that is super easy for backyard bird-watchers to serve.

When Tom Norton of Halls puts out unshelled peanuts, 10 to 12 blue jays often fly in. The peanuts, about three handfuls, or 30 to 35 peanuts, are gone in about two minutes. In winter, blue jays ...