Social, Economic, and Spatial Perceptions of Gray Seal (Halichoerus grypus) Interactions with Commercial Fisheries in Cape Cod, MA

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Orbach, Michael K.

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After more than 40 years of protection via the Marine Mammal Protection Act, the gray seal (Halichoerus grypus) population of the northwest Atlantic has increased considerably. Over the same period, commercial fisheries have boomed, and recently busted, in productivity and profitability. Although commercial fishermen will admit to overfishing, many believe the current abundance of gray seals prevents exploited fish stocks from recovering. In this study, commercial fishermen in Cape Cod were surveyed to assess their perceptions of the local gray seal population and economic costs associated with gray seal interactions. Additionally, a quantitative overlap analysis was performed to examine the extent to which commercial fishing and gray seal behaviors overlap in space and time. Results from the survey showed that 1) commercial fishermen are most concerned with the impacts of gray seals on local marine ecology than impacts on individual fishing operations; 2) both perceptions and impacts of gray seals could fluctuate seasonally; 3) gray seals could pose serious financial threats to commercial fishermen; 4) commercial fishermen would be willing to assist in data collection on the gray seal population; and 5) commercial fishermen believe that gray seals should be managed in the best interest of fisheries and ecosystem health. Results from the spatial overlap analysis corroborate survey results, and indicate potential for overlap between gray seal and fisheries to be greater in summer months than winter months. Overall, this study provides insights for understanding the views held by commercial fishermen, a key stakeholder group involved in this issue, which should be considered when weighing options for mitigating interactions between gray seals and commercial fisheries in Cape Cod.





Gruber, Chase (2014). Social, Economic, and Spatial Perceptions of Gray Seal (Halichoerus grypus) Interactions with Commercial Fisheries in Cape Cod, MA. Master's project, Duke University. Retrieved from

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