Definitions of terms ornithologists use to describe bird migration
Altitudinal migration: Movement from high-elevation mountain habitats to lower elevations and back.|
Band recovery: Any encounter with a banded, dead bird.
Biogeochemistry: The study of earth chemicals that are incorporated into and interact with living entities.
Birds of the year: Individuals that hatched in the current year.
Broad front: Migration in which birds are spread uniformly or randomly over a wide geographic area and do not deviate from their course based on changes in topography.
Complete migrant: A species in which all or virtually all individuals migrate out of the nesting range.
Differential migration: Movements in which one sex or age class migrates before the other.
Diurnal migrant: a species that migrates after sunrise and before sunset. Birds may begin to migrate slightly before sunrise and can continue slightly after sunset.
Echelon: A flock organized in a diagonal line, like half of a V formation.
Elliptical migration: Migration along a non-linear path that generally is farther east in fall and farther west in spring.
Hyperphagy/hyperphagic: Elevated feeding rates of migrants, allowing them to accumulate and store fat for fuel on long flights.
Irruption: A large, often unpredictable movement of birds into an area where they are generally uncommon.
Kleptoparasite: A bird that habitually steals food from birds of other species.
Latitudinal migration: Seasonal movement along a north-south axis with some east-west component.
Migration route: Path followed by a species, not a single bird's exact course. Can be hundreds or even more than 1,000 miles wide.
Migratory strategy: A set of behavioral decisions and other adaptations (geographic, seasonal, and physiological) shaped by natural selection that allow a bird to complete its migratory journey safely and swiftly.
Mist net: A fine, almost invisible net that field ornithologists suspend between poles to capture flying birds for banding.
Molt migration: Migration to an area with the specific purpose of molting.
Morphology: the structure and function of wings, body, and feathers.
Navigation: A bird's use of orientation cues and an internal map to tell it where it is and where it is going.
Nocturnal migrant: a species that migrates after sunset. Birds usually land prior to sunrise, although shorter flights can occur after sunrise.
Orientation: A bird's use of the sun, stars, the magnetic field, or other cues to fly in a given direction and steer a course. Simple orientation is not sufficient for successful migration.
Palearctic: The biogeographic region that includes Eurasia, northern Arabia, and Africa north of the Sahara.
Partial migrant: A species in which a portion of individuals migrates out of the nesting range.
Partners in Flight: an association of non-governmental avian-conservation organizations and governmental wildlife agencies formed to help species at risk, keep common birds common, and foster partnerships for birds, habitats, and people.
Pelagic: Refers to offshore waters as opposed to waters within about a mile of shore.
Phenology: the study of seasonal and cyclic natural phenomena, including climate and plant and animal life.
Resident: A bird that does not migrate, remaining year-round at or near its nesting location.
Satellite telemetry: Use of radio transmitters attached to birds to trace their movements over vast geographic areas via satellites.
Site fidelity: The tendancy of a bird to return to the exact location where it nested, foraged, or wintered in previous years. Also called site tenacity or philopatry.
Skein: A flock in which birds are aligned one in front of the other.
Small front: Migration in which birds from a large breeding range follow a narrow route.
Stable isotopes: Atoms of an element with equal numbers of protons and neutrons. They are not radioactive and do not decay.
Stage, staging: Synonymous with stopover. Used most often when large numbers of waterbirds remain in one place during migration.
Stopover: The time between migratory flights during which birds rest and forage, putting on fat in some cases. May last from several hours to more than a month.
Transequatorial migrant: A migratory bird that crosses the equator.
Vagrant: An individual found outside the normal winter, migration, or breeding range for its species.