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Show Migrating Birds According to the bureau of biological bio-logical survey, few migrating birds fly higher than 3,000 feet and only occasionally do they reach 5,000 feet. Most birds like to fly beneath the clouds, and the majority ma-jority of the species migrate at a height below 1,000 feet. In bad weather they may fly much lower, as evidenced by the number that strike against lighthouses and high buildings. Birds have, of course, been seen at much higher altitudes, alti-tudes, but these records were established es-tablished in mountainous countries where the birds fly a comparatively comparative-ly short distance above the land. The bureau explains that migrating migrat-ing birds fly at low rather than high altitudes by the fact that the lessened buoyancy of air at great heights makes flying difficult. |