Salt marsh harvest mice (Reithrodontomys raviventris; SMHM) are marsh specialists, endemic to the San Francisco Estuary. Over the years, studies have revealed that the SMHM diet is dominated mostly by Salicornia. Salicornia pacifica, a shrub native to salt marshes in the San Francisco Estuary, provides food, shelter and safety from rising tides for SMHM. Salsola soda, a non-native shrub that colonizes salt marshes, is a concern as an invasive species, but its value to native wildlife is not understood. Distinct areas dominated by Salicornia and Salsola at McInnis Marsh in San Pablo Bay provided an opportunity to investigate the use of both vegetation types by SMHM. Live-trapping surveys revealed SMHM consistently utilizing areas dominated by both plant types. While populations in a Salsola dominated managed marsh could reach much higher densities, densities in adjacent tidal marshes tended to be lower, but more stable. Similar results were observed at Hill Slough in Suisun Marsh. A dietary study utilizing fecal metabarcoding revealed further details about foraging behavior and habitat use. More studies focused on the ecological value of Salsola soda in the Estuary are likely warranted to better inform the conservation of protected species and habitats in this highly invaded estuary.

Christian Valdes is a recent graduate from The University of California, Berkeley with a degree in Molecular Environmental Biology and an emphasis on Animal Behavior and Health. He has spent his last two years as the Wildlife Assistant and Technician for Marin County Parks where he has worked on nesting bird surveys and special status species monitoring. Christian’s main passion is conservation and rodents, specifically the Salt Marsh Harvest Mouse. As an Oakland native, Christian hopes to do more work in conserving endemic species all around the Bay Area.