Date of Award

Summer 2019

Project Type


Program or Major

Natural Resources

Degree Name

Master of Science

First Advisor

Robert Robertson

Second Advisor

Stephen Jones

Third Advisor

John Halstead


Oyster aquaculture in New Hampshire is a relatively new industry that has emerged in the last decade. Management of food safety is an integral part of the oyster growing process in this small community. In particular, Vibrio parahaemolyticus is a bacterium that can cause gastrointestinal illness in people who eat raw or undercooked seafood. Recently, New Hampshire created a policy to manage importation of oyster seed for V. parahaemolyticus-related human health concerns. This highlighted a need for data on V. parahaemolyticus in oyster seed. Therefore, the objectives of this research are to examine both social and microbiological aspects of food safety management in the New Hampshire oyster aquaculture community. From a social science perspective, interview and survey data document the experience of industry participants and describe their perspectives on the efficacy and process of food safety management. From a biology perspective, data on V. parahaemolyticus concentrations in juvenile oysters and 16S sequencing data on the microbial community expand our understanding of the microbial implications of oyster importation. A most probable number pipeline (Kaysner and DePaola, 2004) in combination with polymerase chain reaction was used on oyster samples collected over 3 months to compare V. parahaemolyticus concentration in adult vs. juvenile oysters. Samples from the same collection were then used for 16S rRNA sequencing to assess differences in associated microbial communities between age groups and across sample dates. In combination, these multidisciplinary facets are intended to provide managers and industry participants with an analysis of concerns related to water quality and food safety management, a record of interaction experiences between growers and managers, and new microbial data that may inform the management of oyster seed. The results from growers indicate they are mostly satisfied with the effectiveness of food safety management, mostly support a new oyster importation policy, and have positive interactions with state regulators. Microbial results support the scientific underpinnings of the importation policy as a precautionary measure as V. parahaemolyticus was present in juvenile oysters and juvenile microbiomes remained distinct from adult microbiomes for months. Together, these results describe an industry that is operating a management model that minimizes food safety risks, utilizes scientific data, and satisfies the needs of industry members. Elements of this model may be useful to aquaculture industries in other areas looking to develop or improve management strategies.