Poria is the leader of the Coastal Sea People and leaves in a Coralhouse in the depths of the Great Ocean of the Ringworld. Louis Wu had given his people a device to communicate with Dolphins which was stolen by the Explorer from his "sky house" 6000 feet above.
The gatherer Skeenar brought him Quinn who was after a stasis box. Poria needed the translator device to ask help from the Dolphins.