You can cut, copy, and paste a single swimlane at a time.
Cutting a swimlane:
Select the swimlane. Right click and select Cut from the pop-up menu.
Copying a swimlane:
Select the swimlane. Right click and select Copy from the pop-up menu.
Pasting a swimlane:
Select Edit >> Paste.
The swimlane is inserted near the original swimlane.