Magnetic Compass: Birds have an internal compass that allows them to sense the Earth's magnetic field. They use this magnetic sense to determine their direction of travel and stay on track during their long flights.
Sun and Star Navigation: Birds also use celestial cues, such as the position of the sun and stars, to navigate. They can compensate for the rotation of the Earth and adjust their course accordingly.
Landmarks and Visual Cues: Birds also rely on visual landmarks, such as coastlines, mountains, and rivers, to guide their migration. They have excellent vision and can spot these landmarks from great distances.
Sense of Smell: Some bird species may also use their sense of smell to navigate. They can detect certain odors associated with their migratory routes and use these cues to help them stay on track.
Inherited Routes: Migratory routes are often passed down from generation to generation through genetic inheritance. Young birds learn the migratory routes by following older, more experienced birds.
It's important to note that bird migration is a complex behavior that involves multiple factors and adaptations, and scientists are still actively researching and studying the various mechanisms that birds use during their long-distance flights.