Bird Migration and Navigation

These flashcards cover key concepts and terminology related to bird migration and navigation, exploring various mechanisms and sensory cues.

Geomagnetic declination

The deviation between true north and magnetic north.

Map sense

The knowledge of where an individual is, geographically.

True navigation

The ability to locate a given destination and correct for displacement en route.

Olfaction

The sense of smell, suggested to help birds navigate by detecting airborne odours.

Orthodrome

The shortest route between two points on a sphere; a great circle route.

Loxodrome

A path on the surface of a sphere that crosses all meridians at the same angle.

Pinpointing-the-goal phase

A navigation stage mostly based on remembering very specific visual landmarks and/or odours.

Sun compass

A method of navigation that uses the position of the sun to determine direction.

Magnetic compass

A device that uses Earth's magnetism to indicate direction.

Celestial cues

Stellar or solar navigation cues used for orientation during migration.

Landmarks

Visual markers in the environment used by birds for navigation.

Migratory cues

Various sensory information used by birds during migration to navigate their route.

Trigeminal nerve

A cranial nerve that may play a role in the navigation of birds.

Polarised light

Light that oscillates in a particular direction, detected by birds to determine the sun's position even when obscured, aiding in orientation.

Naïve migrants

Young birds without prior map knowledge, typically during first migrations.

Long-distance phase

The navigation stage where birds use global or regionally stable cues to find their way.

Local gradient maps

Maps that rely on learned experiences of local gradients and cues, generated by associating sensory inputs (e.g., magnetic intensity, odor landscapes) with geographic location.

Experiments showing navigation mechanisms

Studies that demonstrate how birds use various cues and compasses to navigate.

Multi-compass integration in bird migration

The use of redundant and complementary compass systems (e.g., sun, magnetic, stellar, polarized light) by birds, allowing for orientation even if one cue is unavailable or unreliable, and potentially cross-calibrating between them.

Navigational benefits of migrating at dusk/night

Reduced predation risk, cooler temperatures (conserving energy and preventing overheating), more stable atmospheric conditions (less turbulence), and the availability of stellar cues for navigation.