Secretive marsh birds are a guild of species for which baseline and overall population trends are lacking. Avian surveys were conducted in Florida to estimate abundance for eleven species of marsh birds, using the Standardized North American Marsh Bird Monitoring Protocol. Multiple scales ranging from 0.785-7,850 ha were used in conjunction with single-season N-mixture models to estimate abundance. There were discrepancies between years in top models, but results in general were consistent with other studies and top models included variables from multiple scales. Clapper rail blood and invertebrate samples were tested for heavy metal contaminants, and several birds exhibited levels above known toxic thresholds. Invertebrate levels were within the range of other reference levels. Complete blood counts and biochemistry panels were measured to assess clapper rail health, and findings were mostly within normal ranges for species within the same order.