Nevertheless, all behavior shows some refinement with age or experience. For example, gull chicks become more accurate with pecking as coordination improves with practice. This indicates that even innate behaviors are modified by experience. Consequently, it becomes difficult to determine just how much of a behavior is genetic and how much is a product of the environment in which the bird lives. This difficulty is commonly known as the Nature vs. Nurture Controversy.
Birds also use experience to recognize predators by observing mobbing behavior in other birds.
Eurasian Blackbirds will mob a Chlorox bottle if they've seen other birds mob the bottle. Examples include parent birds feeding open mouths, fear response to predators, and brooding behavior. Imprinting also is involved in such things as adult habitat preferences, selection of nest sites and materials, etc. Important in modifying Fixed Action Patterns to fit environmental circumstances more precisely. A good example is tool using in birds.