The salt marsh harvest mouse (Reithrodontomys raviventris, SMHM) is an endangered species, endemic to the wetlands of the San Francisco Bay Area. Habitat loss and fragmentation are some of the largest threats to the species, and these threats can be exacerbated by other factors such as sea level rise. In smaller, fragmented habitats with little high tide escape cover SMHM are more vulnerable to climatic events such as winter flooding. After heavy rains during the winter of 2022-2023, we wanted to evaluate the effects on SMHM populations at sites throughout their range. To do this, we re-trapped a subset of sites that were part of the SMHM range wide survey in summer 2022 and sites in Suisun Marsh that are part of long-term monitoring efforts. At all sites but one SMHM captures were lower than the previous year, and we found a significant decrease in catch per unit effort. This study highlights the importance of long-term monitoring efforts and regular monitoring of SMHM populations especially as the frequency of stochastic events like seasonal flooding increases. Regular monitoring will help managers gain a more accurate understanding of the status of SMHM, guiding future conservation and management.