Anne McCaffrey

At a time when the number of Dragonriders has fallen too low for safety and only one Weyr trains the creatures and their riders, the Red Star approaches Pern, threatening the planet with disaster.

Since Lessa and Ramoth, her golden queen dragon, traveled into the past to bring forward a small army of dragons and riders to save their world from deadly alien spores, fear and desperation have spread across the land. But while the dragonriders struggle with threats both otherworldly and human, a young rider name F'nor and his brown dragon, Canth, hatch a bold plan to destroy the alien scourge at its source--the baleful Red Star that fills the heavens...

“[Anne] McCaffrey here adds yet another dimension to her colorful and vivid saga by focusing on the attractive dolphins and their highly believable society.”—Publishers Weekly
When the first humans came to settle the planet Pern, they did not come alone: intelligence-enhanced dolphins also crossed the stars to colonize Pern’s oceans while their human partners settled the vast continents. But then disaster

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NEW YORK TIMES BESTSELLER
 
Even though Lorana cured the plague that was killing the dragons of Pern, sacrificing her queen dragon in the process, the devastating disease has left too few dragons alive to fight the fall of deadly Thread. As morale at Telgar Weyr plunges in the wake of the widespread loss, and Weyrwoman Fiona and the harper Kindan struggle to keep hope from vanishing, a pregnant Lorana decides she must take...

Menolly flees her home, because she is not permitted to make music there, and is taken by the Masterharper himself to Harpershall, where she learns that only her own self-doubt stands in her way.

With the help of her "uncles" and the thousands of humans who love and admire her, Acorna has found her true people, the peaceful, telepathic Linyaari. But Acorna still has much to do before she can enjoy her new home. The legendary resting place of the lost Linyaari ancestors has yet to be found. And with the help of a rogue spacetrader and his feline sidekick, Acorna must strive to right an unspeakable wrong and defeat an enemy even crueler than...

Sean Shongili and his children, Ronan and Murel, must draw on their changeling ability to transform into seals when a mysterious race of aliens is discovered to be living in the depths of the ocean on the planet Petaybee.

As a deadly epidemic sweeps across Pern, only Kindan, a young apprentice to the guild of musicians and teachers known as the Harpers, recognizes the imminent peril and must come up with a way to stop the illness from spreading.