Suet is the kidney fat from a cow. It is a staple for most bird feeder stations in the cooler months but can be fed year round. While many species of woodpeckers, chickadees, titmice and others love suet, it can be a challenge to feed due to other less desirable species that are attracted to it. Raccoons in particular can be quite frustrating to deal with while European Starlings are by far the worst feathered pest. Several designs are available in the suet feeder world and each has its advantages depending on your particular need.