Salt marshes will vanish in less than a century if seas keep rising and California keeps building, study finds

On one side, there’s the rising ocean. On the other, rising buildings.

Squeezed between the two are California’s salt marshes — a unique ecosystem filled with pickleweed and cordgrass, shorebirds and many endangered species.

Coastal wetlands such as Bolinas Lagoon in Marin County, the marshes along...