Outrigger trawlers Outrigger trawlers use outriggers, or booms, to tow the trawl. Otter trawlers Otter trawlers deploy one or more parallel trawls kept apart horizontally using otter boards Stern trawlers Stern trawlers have trawls which are deployed and retrieved from the stern. Freezer trawlers The majority of trawlers operating on the high seas are freezer trawlers