The Swarm's ships, oddly, arent all classed as living. The Crab, the factions cruiser, and its Capital Ship, the Wormship are living ships. Its Frigate, The Bug and its Battleship, also called the Wormship, are not living ships.
All living ships possess a small amount of passive regeneration, exactly 1% per second. This makes attrition warfare against these ships ill-advised.