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Spring chinook salmon spawning occurs in late summer when it is common for cattle to be present in pastures that have streams where fish spawning occurs. This two-year study addressed three main objectives relative to behavioral interactions between cattle and spring chinook salmon during the spawning life history stage. These objectives were 1) to determine cattle distribution and behavior within the riparian pasture, 2) to determine ifcattle disrupt the spawning behavior ofsalmon by their presence near the redd and 3) to determine the likelihood ofa cow coming into direct contact with a redd. This study did not measure the changes in redd structure or egg survival ifcontacted by the cattle. The study area was a 41 hectare riparian pasture along an Eastern Oregon stream with cattle stocked at a rate of0.82 ha/aum and spring chinook salmon spawning at densities of4.6 redds per kilometer in 1996 and 6.1 redds per kilometer in 1997 in areas accessible to cattle. The pasture contained 2.6 kilometers ofstream with approximately 50 % ofthe 2.6 kilometers ofstream excluded from cattle since 1978. From mid-August through early-September in each ofthe two years, cattle and salmon distribution and behavior were recorded every minute for two out ofthree four-hou