Resource managers attempting to rehabilitate degraded desert riverine ecosystems must understand the effects of vegetation management on riparian wildlife. I used capture-recapture methods in February, june, and September 1992, and February 1993 to investigate demography of small mammals at a 4-ha site on the xerified lower Colorado River floodplain, 5 years after treatment to replace saltcedar (Tamarix ramosissima) with native woody plants. The site had become a mosaic of various vegetation types, including closed-canopy cottonwood/willow (Populus fremontii/Salix nigra), with no natural counterpart. I captured 9 of 15 native small mammal species potentially resident in local riparian habitats