How are airliners secured on the ground during hurricanes?
Looking at the hurricane manuals for a few airports, evacuating flyable aircraft to a safer location tends to be the most common choice.
From the Boca Raton Airport: 

Effective with the issuance of a Storm WARNING and/or Hurricane WARNING:
Relocate flyable aircraft to other geographical areas, place under suitable shelter, or secure as appropriate.

Also, from the Miami International Airport:

Upon receipt of a Hurricane Warning, Airside Operations will:

Initiate evacuation of all flyable aircraft and post Airfield Operations Senior Agents and Agents in detail to insure compliance and report results.