 When feeding wild birds the Royal Society for the Protection of Birds (RSPB) suggests that it be done year round, with different mixes of nutrients being offered each season.Selections should have additional fat content in the winter months, and additional proteins in the form of nuts, seeds and dried worms in summer when birds are changing their plumage and may be molting.Farmed birds fed commercial bird food typically are given very specific scientifically designed pre-blended feed.