A total of 710,450 observations were made. The study found that black oil sunflower is the most popular seed with most seed-eating birds. White proso millet is the most popular with sparrows and doves. Common cereal grains milo, wheat, cracked corn, and oats as well as flax, canary, and rape seeds rate significantly lower than sunflower and millet. Since bird populations differ from place to place and change from time to time, it is almost impossible to formulate an entirely satisfactory seed mixture.
Birds differ in how they feed.
Some feed almost exclusively 4 ft. or more above ground level on elevated feeders. Others feed on the ground or on a slightly elevated platform. Still others will feed wherever they can find food. In general, birds attracted to elevated feeders prefer sunflower seed while ground feeders prefer millet. Tube feeders with small perches should be filled with some type of sunflower seed black oil, striped, or hulled.