Green crabs

Researchers need the public's help in determining how many green crabs there are on the state's coastline.

RYE -- Citizen scientists are needed to help track invasive green crabs on the Seacoast.

Green crabs are a problem in New Hampshire because they disrupt ecosystems and reduce biodiversity. Each crab can eat up to 40 clams or oysters a day.

At the same time, they are considered delicacies in Italy, Spain, China and the Philippines. There is a local movement to use them in food products -- they are being made into appetizers, soups, stocks and chowders.

Fisheries Specialist Gabriela Bradt works for the UNH Cooperative Extension and New Hampshire Sea Grant. She is hoping people will turn out to help these groups find pre-molt or molting green crabs in Rye, Hampton, Portsmouth and Dover so the groups can determine the scope of the problem and the potential for selling larger crabs to restaurants and the public.

“I’d love it to be a blanket measurement but based on data from last year we picked the five sites we think would be potential hot spots,” Bradt said of the research.

The pre-selected locations are Rye Harbor, the drowned forest in Rye, Hampton Harbor, Peirce Island in Portsmouth and Hilton Park in Dover.

Bradt is asking people interested in participating in the "find the invaders" project to sign up using an app from Participants will be asked to document how many crabs they see during a one-hour time period, how big they are, if they have a hard or soft shell and whether the crabs are male or female.

“It’s good for kids. They’re super hunters,” Bradt said.

Bradt said people can adopt a spot in one of the five locations and visit it twice a month or go out on their own.

“I will take the data from wherever they are,” Bradt said.

The only rule is people cannot harvest the crabs if they are counting in a state park.

Bradt said male green crabs will be molting through mid-June and that the females will be molting from mid-August until mid-September.

There is a green-crab hunt scheduled for June 8 at the Seacoast Science Center in Rye for those who would like to participate in a group session. Additional hunts will be planned afterward, until October.

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