Plankton harvester

A plankton harvester was a type of submarine, an aquatic vessel used for harvesting undersea plankton on the planet Nordstral.

History and specifics
They were aquatic craft used under the ice sheets of Nordstral. Each was capable of harvesting millions of tons of a type of plankton called magnetic biota. A fleet of them was owned by Nordstral Pharmaceuticals and employed both Humans and native Kitka. Shore-based docks were used to supply and fuel the vessels, as well as to receive the harvested plankton. Quarters were cramped to maximize cargo space. Outings were long and monotonous for the crew.

James T. Kirk and Leonard McCoy traveled aboard one of them in 2274 to investigate magnetic disturbances and outbreaks of insanity among the employees and staff. 

Named vessels

 * Cousteau
 * Soroya