The Great Green Crab Hunt… and hunt for a new fishery

Dr. Gabriela Bradt (PI)

NH Sea Grant Fisheries Extension Specialist

Seacoast Science Center began working with Dr. Gabriela Bradt, NH Sea Grant Fisheries Extension Specialist, in 2018 to collect intertidal data on the nefarious invasive Carcinus maenus. The NH Green Crab Project began as a pilot project in 2015 to determine whether soft-shell green crabs could be a viable seafood product in the state. The European green crab (Carcinas maenas) is a non-native crustacean that invaded the US Northeast region from Europe in the early 1800’s. Since then, these invasive crabs have firmly established themselves and have spread from Cape Cod to Prince Edward Island, Canada, destroying economically important wild harvest fisheries (soft-shell clams) and vitally important coastal and estuarine ecosystems. The initial goals of the NH Green Crab Project was to detect a visible morphological molting sign that would help fishers identify crabs that were about to ‘bust’ out of their old shell and become temporarily soft -which was the desired edible product- similar to the popular and  lucrative soft-shell blue crab industry in the southern United States. While researching molting cues, it became clear that in order to develop a market, there also needed to be a potential fishery for these crabs and the idea for finding large aggregations of pre-molt crabs spatially and temporally in New Hampshire gave rise to the citizen science monitoring component of this endeavor. The Great Green Crab Hunt is a multi-faceted approach to engage citizens through interactive field data collection to better understand when and where these crabs begin the molting season and in large numbers. The data collected by participating citizens then gets uploaded to an online map that updates in real time and shows where potential green crab ‘hotspots’ are located. Other data collected such as sex, shell hardness, color and size also contribute to a better understanding of the seasonal molting patterns and overall green crab population ecology. The NH Green Crab Project has successfully molted and produced soft-shell crabs and provided them to local restaurants to begin market development, and the Great Green Crab Hunts, which began in 2018, have already engaged 150 citizens (all ages) and several  ‘hotspots’ are beginning to emerge- Peirce Island (Portsmouth), Goat Island (New Castle), Drowned Forest Beach (Odiorne) and Cedar Point (Dover).

For more information please visit the project website or Online Map

Leave a Reply

Your email address will not be published. Required fields are marked *

%d bloggers like this: