BIRD PESTS Several species of birds cause problems in Utah. The problems include roosting and defecation, consumption of grain, contamination of feed, and transfer of diseases. Problem species include feral pigeons, starlings, house sparrows, woodpeckers, and magpies. In addition to birds covered in this guide other birds such as ducks, geese, seagulls, cormorants, mergansers, herons, cranes, crows, ravens, blackbirds, eagles, owls, vultures, and swallows occasionally cause problems in Utah.