One of the many pleasures of beachcombing along the shores of Puget Sound is the immense variation in the colors of the stones—deep purple, jade green, burgundy, caramel, speckled or striped black and white. To wanderers, it looks like a beautiful carpet but to marine scientists the diversity tells an exciting story about the geological evolution of our region.

The new book The Salish Sea: Jewel of the Pacific Northwest (Sasquatch Books, $24.95) looks at these local waters through a scientific lens, illustrating the region’s unique geology (thanks to glaciers, plate tectonics and volcanoes) and vibrant marine ecology. Written by biologist Audrey DeLella Benedict with Joseph K. Gaydos, chief scientist for the SeaDoc Society (an Orcas Island–based conservation group focused on the Salish Sea), the book pairs bright, bold, photographs with fascinating facts about local sea creatures. (Did you know that the Salish Sea is home to the world’s largest species of barnacle, octopus and burrowing clam?)

A substantial celebration of orca whales, sea lions, otters, salmon, sea anemones, eagles, eels and others, the book is moreover a compelling reminder that the humans who live near this body of water must work to ensure the survival of its residents.