Soft-shell clams

Project overview

This project explores the Maine soft-shell clam (Mya arenaria) fishery. This low-cost intertidal fishery provides an important source of income for more than 1,500 state-licensed shellfish harvesters. The soft-shell clam fishery is an excellent setting to study co-management and how resource management decisions impact resource users. Coastal municipalities can apply to co-manage their clam flats with the state. These Municipal Shellfish Ordinances provide municipalities with the power to require additional licensing (in addition to the state shellfish license) as well as perform clam flat enhancement projects, including conservation closures, reseeding flats, etc. Further, the state can issue temporary clam flat closures due to bacterial pathogens and biotoxins to protect the health of shellfish consumers and the industry. My research on this project focuses on: (1) the impact of harvest and access restrictions (e.g., temporary clam flat closures), and (2) connections between fishery outcomes and the seafood supply chain.

This research is supported by the National Science Foundation under EPSCoR award #IIA-1330691 and the USDA National Institute of Food and Agriculture under Hatch project #ME021704.

Impact of harvest and access restrictions

Published work:

  1. Evans, K.S., K. Athearn, X. Chen, K.P. Bell, and T. Johnson. (2016) "Measuring the impact of pollution closures on commercial shellfish harvest: the case of soft-shell clams in Machias Bay, Maine." Ocean & Coastal Management. 130: 196-204.
    • This work has been used by the Maine DMR to discuss the importance of improving water quality conditions and reducing the frequency of these closures.

Ongoing research:

  • Statistical analysis measuring the impact of temporary environmental closures - which reduce accessible acres of clam flats to harvesters - on landings and revenue along Maine's coastline. (with Hannah Merriam)
  • Dynamic analysis investigating averting behavior by clammers to reduce the personal impacts of temporary clam flat closures. Special attention is given to the various causes for these environmental closures (e.g., coastal flooding and harmful algal blooms), some of which may be consistently anticipated by clam harvesters.
  • Investigate the effectiveness of Municipal Shellfish Ordinances - which allow participating municipalities to enhance clam flats (e.g., conservation closures and reseeding projects) and limit entry - as a rent-generating co-management tool.

Connections with the seafood supply chain

Ongoing research:

  • Exploration of the relative impact of regional and local factors on the ex-vessel price of soft-shell clams in Maine. (with Hannah Merriam)

Graduate student miscellany

Shuling Chen, MS Marine Policy (2018)

Hannah Merriam, MS REP (1st-year)