An animal migration is simply the movement of large groups of members of a single species from one place to another; not necessarily during a certain season. Many kinds of animals migrate; birds, insects, ocean dwellers, amphibians, mammals, etc. In her article "Animal Migration", Silke Nebel mentions that animals migrate because of instinct evolved from changes in resource availability due to the current season and/or location over many years. When animals prepare for migration, they either eat a lot beforehand or eat and forage during the journey. The animals’ body weight and organ size may also differ before and after the migration. During the migration itself, animals may use landmarks, the sky, or even magnetic cues to navigate. Migration is triggered most commonly by the length of days (how many hours the sun lights the sky) and the reproductive cycle. Animal migrations are commonly studied using banding, radar, and tracking devices. Bird banding involves placing aluminum bands on the legs of migratory birds and having people who encounter the birds on their way and at their destination send back data. Today’s radars are powerful and advanced enough to plot the location, speed, and wing beat rate of birds and bats. Sonar radars can detect groups of fish migrating as well. Tracking devices work the same way as banding, except they are more technology based and send migratory data back automatically.
The article "Animal Migration" showed a relationship between evolutionary animal behavior and the timing of migrations. The article also displayed a connection between an animal's behavior and whether it eats before a migration or not, which is important because it affects the health of the animal overall; if it does eat before it will store a lot of fat, if it doesn't its organs will change accordingly.
I wonder how global warming has effected or if it has effected migration.
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