Most song birds stay below 500 ft during their daily activities. Flying higher than this uses a lot of energy and exposes them to predators. Vultures may soar as high as 5,000 to 10,000 feet to scan large areas for food.

During migration many species fly from 5,000 to 10,000 feet and long distant migrants may go as high as 20,000 feet.

Turkey vultures soar on thermals to great heights when looking for food and during migration.

Perhaps the highest recorded sighting was a flock of whooper swans identified by an airline pilot over Ireland at an altitude of 29,000 feet!