The Eel River, located in north central Indiana, has been the subject of numerous fish surveys since a dramatic absence of smallmouth bass was documented in the early 1980's. While these surveys have provided important data, none have focused on a particular stream reach over multiple field seasons. Through the months of May and June 2006 and 2007, chemical, physical, and biological data were collected regarding the population, habitat, spawning, prey selectivity and year class strength of smallmouth bass (Micropterus dolomieui) in the Eel River near North Manchester, Indiana. Nest surveys were conducted weekly by snorkeling and/or by wading over a 2.5 km stream reach. Fish clearly preferred nest sites in back eddies where water velocities were less than 0.1 m/sec and water depths were between 30 and 40 cm. In 2006 seven nests were located and five different spawning attempts were documented. The mean stream discharge for this time period was 31m³/sec SE 0.3. In 2007 twenty nests were located and the mean stream discharge was 6.6 m³/sec SE 0.5. Only 25% of the nests observed in 2006 were successful while 100% of the 2007 nests produced offspring. The largest number of black fry produced in 2006 from any nest was 39 and the largest number of sac fry counted was only 139. In 2007 over 500 black fry were observed and over 1,500 sac fry were counted in at least one nest. The population M. dolomieui was estimated to be 58 in a 500m reach using the Zippin depletion method in 2006 and only 16 in 2007. Chemical and physical parameters were also measured during low flow and rain events over the spawning periods of 22 May -30 June 2006 and from 1 May- 30 June 2007. Of these data, the most striking were elevated levels of total phosphorus exceeding 1 mg/L and total suspended solids (TSS) greater than 30 mg/L.