Sea Ballasts

Sea Ballasts, while relatively harmless, can cause havoc for ships trying to navigate the turbulent waters of the Primus Territory. These golem-like creatures can be found anywhere, but primarily reside just outside the Bay of Telluride. Researchers believe they a more mobile form of coral reef, feeding on clouds of plankton where it can find them. While relatively slow, Sea Ballasts can move up to a mile a day, if motivated. They have an innate sense of local plankton density, and will move to richer areas if required. 
The danger of these creatures occurs when they wander into high-traffic areas in search of food. Vessels not paying attention to updated nautical charts or their navigation equipment are in danger of gashing their hull on the crags of a wayward Sea Ballast. One may think that these slow-moving hulks could be moved, but such an option would be a far cry as the average-sized sea ballast weighs close to 200 tons.