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Survival and growth of the Pacific oyster Crassostrea gigas along the Pacific coast of the United States are adversely affected by burrowing shrimp Neotrypaea californiensis and Upogebia pugettensis.In Washington State (USA), the insecticide carbaryl has been applied to oyster beds to control populations of shrimp for more than 30 years.While carbaryl removes adults from oyster grounds, it does not discourage reinvasion by young-of-the-year (YOY) shrimp.We initiated a study to examine how the harvest and culture of oysters affects recruitment success of burrowing shrimp.Young-of-the-year abundance was quantified prior to and 2 wks after dredging a mature oyster bed to assess whether active methods of disturbance, such as harvest operations, might kill YOY shrimp residing in shallow burrows.We found no conclusive evidence, however, that dredging had a significant impact on shrimp density distinct from natural mortality.Young-of-the-year shrimp were also quantified in areas of oyster culture and dense epibenthic shell cover to determine if shell configuration (i.e., structure and percent cover of shell) affects recruitment success.Mean densities of N.californiensis were significantly lower in a mature oyster bed and an area of dense epibenthic shell than in a seed bed and an open mudflat.Results of field and laboratory experiments indicate that epibenthic shell hinders recruitment of N.californiensis by acting as a physical barrier to settlement and harboring high densities of YOY Dungeness crab, Cancer magister, which prey on newly settled shrimp.In contrast to N.californiensis, however, mean densities of YOY U.pugettensis were significantly higher in epibenthic shell habitats than open mudflat; mechanisms underlying their patterns of distribution currently are being investigated.It is hoped that information on shrimp recruitment will aid in developing an integrated pest management plan to achieve more effective long-term management of shrimp populations in areas of bivalve culture.