Factors Involved in Bird Food Selection
By Dave Hanks
Bird food selection is restricted by the type of beak each possesses. A strong flesh tearing bill allows a hawk to eat mammals, reptiles, or other birds. Thick, strong beaks facilitate the woodpeckers feeding habits. Scoop-like bills favor the consumption of aquatic plants. Seed eaters have shorter beaks that are thick at the base. Food is available on many levels: on or beneath water surfaces, ground surfaces, on bushes and in trees, and even in the air where bugs are consumed while the bird is in flight.
Seed eating species show a preference to select the largest seed that can be opened with minimum energy expenditure. Flight demands a high caloric intake, and this requires the obtaining of the most calories in the most economical way. Sunflower seeds are a big favorite of many seed eaters.Blue Jays can crack these seeds by holding each down with their foot. Cardinals, with heavier beaks can crack them with their bills, but birds with weaker bills, like chickadee and PINE SISKIN must work harder – hammering away until a crack is opened.
PINE SISKINS are a “winter finch” and may look quite plain until they display their yellow wing stripes and tails. The yellow can be highly variable from individual to individual. This is a species that selects small seeds, especial thistle, red alder, birch, and spruce seeds. They will also take insects.
Siskins breed in coniferous forests, but will form large flocks in winter, and can be common at bird feeders at this time. Nyger or thistle seed presented in a hanging sock is an attraction, as are sunflower seeds, suet, and a water source. Pine Siskins are a perky and sociable member of the finch family.
(Pine Siskin – Yellow wings distinctively apparent)
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