Copyright, Marlin E. Rice
When larvae are full grown, they will crawl from the water and burrow into mud or soil. Terrestrial species are already there.
Next, they will become pupae (resting stage) where they will slowly change into adult Crane Flies. Usually, they will spend the winter in the mud before they hatch the following Spring.
Large amounts of Crane Flies hatch at the same time, and swarms of males "dance" above treetops looking for females.