Rancho del Oso is home to the Theodore J. Hoover Natural Preserve, a coastal freshwater marsh that is one of the rarest habitats on the Central Coast. This habitat shelters many rare and endangered species such as the California red-legged frog, Western pond turtle, tidewater goby, black rail, San Francisco garter snake, coho and steelhead salmon. Working with experts from other areas, the Waddell Creek Association hopes to educate the public about wetlands, their value and necessity.