Pernese Dolphins are Mentasynth-enhanced bottlenose dolphins whose ancestors agreed to be brought to Pern by the original settlers. The 25 original dolphins were attracted to the prospect of being able to preserve their species in new, unpolluted seas. Their descendants grew and multiplied until they ranged across all of Pern's oceans. They can talk to humans and treat everything as a game.
All dolphins are named on a variation of the 25 ancestors' names from Earth.
Dolphineers were certain humans who dedicated their lives to helping dolphins and using their information to help other humans.
- Long-feet — Scuba flippers
- Sick ocean world — Earth
During the intervening Passes humans forgot about dolphins, but the dolphins, by use of revered oral tradition, did not forget about the how and why they existed on Pern in the first place. They continued to save shipwrecked sailors and tried to lead humans away from reefs and towards the fish shoals. Humans began to call them «shipfish» because they followed boats. The dolphins waited and passed down their oral history through female dolphins chosen to be the leader of their species, called 'The Tillek', in honor of Captain James Tillek, captain of the Bahrain and sea captain who worked extensively with dolphins. Dolphins waited for the dolphin bells to ring and for humans and dolphins to resume their ancestral partnership.
Whenever a rescued seaman related the tale that when they were rescued it sounded like the shipfish were talking, they were dismissed as crazy until Masterfisherman Alemi distinctly heard the dolphins speaking and carried on a short conversation. AIVAS said that group of Tursiops truncatus agreed to the treatment of Mentasynth, which is passed down via their genes; this proved that they were talking, and AIVAS recommended that contact be resumed. Alemi found the Monaco Bay "doll-fin bell, " recently retrieved from the bottom of the sea, and rang it. Dolphins came to answer the call and spoke to Alemi. Other contact was done by T'lion, rider of bronze Gadareth, and Readis, of Paradise River Hold. The dolphins led ships safely to the shoals of fish and away from reefs and warned of storms. One of the acts humans performed in return was scraping off parasitic bloodfish. Masterfisherman Idarolan and Weyr healer Persellan were skeptical at first, but later became confident in delphinic abilities. Persellan helped treat several wounded dolphins and used their sonar to diagnose human pregnancy and unnatural growths.
Readis never forgot being rescued by dolphins as a child and always tried to play with them whenever he got a chance. Once, the dolphins warned him that he had a bad sea thorn in his foot, and Readis, not finding anything, dismissed it. Several days later, it became severely infected and his leg was crippled for the rest of his life. His mother Aramina blamed it on the dolphins. After a huge storm, when Readis helped the wounded dolphins without checking on the rest of the Hold, his mother told him to promise to never do anything with the «shipfish» again. As Readis couldn't keep that promise, he didn't make it and instead rode away from the hold on his runnerbeast. He found a series of sea caves and started to work with dolphins. The nearby dolphins found a bell for him and were ecstatic to have a pod dolphineer. After Readis had worked for a while and was well-known among dolphins, the dolphin leader, known as the Tillek, came and collected him and brought him to his family, friends, and some important personae aboard the Fair Winds, where Readis was formally made head of a Dolphin Hall located at the sea caves, along the Rubicon River of the newly named Rubicon River Hold.