The White Bluffs bladderpod (Physaria douglasii subsp tuplashensis) is restricted to caliche soils above the Colombia River in Franklin County, Washington and is currently known from a single population. White Bluffs bladderpod population size has been trending downward since monitoring began in the 1990s presumably due to increased human activity and climate change. Due to the restricted range and small population size White Bluffs bladderpod is at risk of having low genetic diversity and high levels of inbreeding. We are proposing to assess the extinction risk for Physaria douglasii subsp tuplashensis by 1) evaluating genetic diversity, 2) effective population size and 3) determining the extent of pollen movement. Results found will help to inform conservation management of the White Bluffs bladderpod.