Date of Award



© 2021 William L. Walter

Document Type


Degree Name

Professional Science Master's (PSM) In Ocean Food Systems


Marine Science

First Advisor

Zachary Miller-Hope

Second Advisor

Barry Costa-Pierce

Third Advisor

Marissa McMahan


The European green crab (Carcinus maenas) is a well-adapted invasive species that has flourished throughout coastal New England. Its arrival has caused numerous negative environmental and socioeconomic impacts, including the decline of the Maine soft shell clam (Mya arenaria) fishery. Increases in north Atlantic sea surface temperatures have simultaneously propelled the proliferation of C. maenas and caused northward shifts in the geographic ranges of commercially relevant species, including the American lobster (Homarus americanus). C. maenas represents an underutilized species that H. americanus and M. arenaria fishers can target to supplement any lost income if C. maenas markets are economically viable. The research explores the development of the C. maenas fishery, describes any barriers to the industry and dissects the economic feasibility of markets based on minimum price points and current landings data. Maine-based fishers were interviewed regarding their views on the current industry and the principle obstacles facing the industry. Past and current landings data was analyzed to determine trends in economic value. The biggest barrier to further industry development is the price per pound of hard-shell crabs. The market value of current landings is far below the threshold of what is considered acceptable to fishers, but the price point is rising. For the fishery to expand, consumer demand must be created. Stakeholders should target farmers markets and chain grocers to further market product. This study was conducted with a limited sample size and analyzed just the perspectives of one sector of the seafood supply chain. Future studies should operate on a larger scale and evaluate the viewpoints of wholesalers and consumers.


Professional Science Masters Thesis

Advisors Miller-Hope and Costa-Pierce are UNE faculty members; advisor McMahan is with Manomet.