Migration

Definition

In animal behavior and ecology, the seasonal or periodic movement of individuals or populations between distinct habitats or geographic regions, typically involving outbound and return journeys linked to resource availability, breeding, or climate cycles. Distinguished from dispersal (permanent relocation) and ranging (routine foraging movements) by its predictability, repeatability, and often genetically programmed nature across generations.

Etymology

Latin migrare, to move from one place to another

Example

Monarch butterflies (Danaus plexippus) undertake multigenerational migration, with successive generations traveling northward in spring and a single generation completing the southward return to overwintering sites in Mexico.

Synonyms

• seasonal movement
• periodic movement

Related Terms

• Dispersal
• nomadism
• irruption
• range expansion
• philopatry
• homing
• orientation
• navigational behavior
• stopover ecology
• partial migration
• altitudinal migration

Usage Notes

Specialists distinguish true migration (innate, population-level, bidirectional) from facultative movements triggered by immediate conditions. In insects, migration often involves distinct morphs (migratory vs. sedentary phases, as in locusts). The term is sometimes applied loosely to unidirectional irruptions or range shifts; precise usage reserves 'migration' for cyclic, large-scale displacements with return tendency. Arthropod examples include dragonfly pond-to-pond movements, spider ballooning dispersal (when seasonal and directional), and armyworm moth nocturnal windborne migrations.