The Appalachian Mountains: A Free Lift for Monarchs
When the wind is right, the Appalachians provide "ridge lift" for migrating monarch butterflies, as well as hawks, dragonflies and other birds and insects. Monarchs can use ridge lift to gain altitude, and then soar effortlessly along the mountain ridges.
 
Ridges of the Appalachian Mountains

Ridge Lift: The Appalachian Mountains provide 'ridge lift' for migrating monarch butterflies.

Ridge Lift
When the wind hits the ridge, the air rises. This rising air provides lift all along the ridge.

Glider pilots can use ridge lift to stay aloft for hours.

A Free Lift
Glider pilots can use ridge lift to stay aloft for hours, without an engine or fuel!