Migratory birds use a variety of navigational cues for finding their way between their breeding and wintering sites. Birds that travel by day, including hawks and vultures, swallows, swifts and nighthawks use the angle of the setting sun (and the pattern of polarized light created), land features such as mountains and rivers, and wind direction. Birds that travel by night or over vast ocean distances, such as warblers, swallows and thrushes, use a combination of star patterns, the earth's magnetic field, and odors. At least some birds can detect ultraviolet radiation and very deep sound vibrations such as distant ocean waves. When one set of cues is obscured, as the sun and stars may be by cloud cover, more reliance is placed on alternate cues.
Many short-distance migrants and most waterfowl species learn migration routes as young birds from their more experienced family members. Long-distance migratory birds are genetically programmed to fly in a particular direction for particular time periods. As they become more experienced, they integrate information they have learned from earlier migrations, such as agreeable wintering or breeding locations.
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Mid-twentieth century planetarium experiments with indigo buntings demonstrated that birds oriented themselves by the pattern of stars around the North Star and that, when prevented from seeing the night sky during a critical stage of development, were unable to properly orient for migration. Related laboratory experiments revealed that European robins changed their orientation in response to shifts in an artificial magnetic field that mimicked the Earth's natural field, and European starlings altered their orientation when mirrors were used to shift the sun's image.
Encompassing artistic interpretation of historical scientific tools and models, MMoCA's exhibition Starry Transit: An Installation by Martha Glowacki, permits visitors to Washburn Observatory to simulate processes of research and discovery about bird migratory navigation by constellations.