RECONSTRUCTING GEOSPATIAL DISTRIBUTION OF THE OLYMPIA OYSTER (OSTREA LURIDA)

Oysters are bedforming bivalves that provide ecosystem services including water filtration, habitat formation, and wave dampening. There are significant knowledge gaps about the Olympia oyster (Ostrea lurida), the only oyster native to the North American west coast, that hinder the restoration and conservation of this species. O. lurida (synonymized here with the southern variant O. conchaphila) became the dominant oyster of its range in the early Pleistocene (ca. 2 Ma) and was overharvested to the brink of extinction in the 1800s and 1900s. Many coastal community organizations, including family oyster farms and nature reserves, are interested in restoring native habitats by reintroducing O. lurida.

In this study, we collected and visualized over 1000 observations of O. lurida occurrence and distribution using sixteen digitized museum repositories and the Paleobiology Database. Many of these occurrences were digitized as part of the Eastern Pacific Invertebrate Communities of the Cenozoic (EPICC) project.

Here, we present a geospatial synthesis of historic O. lurida occurrence data across their native habitat of the North American west coast and evolutionary history, examined in the context of the paleoenvironmental history of this region. We find a high density of occurrences in protected bays, particularly the San Diego Bay, but a vast latitudinal range. By improving our understanding of the history of O. lurida, we contribute to a fundamental understanding of the organism’s biogeographic history and environmental constraints.