The Black Shore (Star Trek: Voyager)

The Black Shore is the tenth book in the main Star Trek Voyager series.
==Book Description==
After weeks of lonely journeys through a desolate region fo the Delta Quadrant, the crew of "Voyager" is badly in need of shore leave, so the planet Ryolanov seems just what the doctor ordered. Full of warm sunlight and gracious, hospitable people, Ryolanov is a veritable oasis amidst the endless reaches of uncharted space.
Alerted by his spirit guide, Chakotay is the first to suspect that there may be a serpent lurking in this paradise, but he is not alone. Driven by a psychic call she cannot ignore, Kes must conquer her own fears to discover the terrifying secret lurking 
beyond the black shore.
(Description from Amazon.com)