Ipswich program aims to cull out invasive crabs

Ipswich recently began a program to reduce the number of an invasive species of crab that is threatening the region’s native crab population, which is significant to the local economy.

A plan developed by Ipswich Shellfish Constable Scott LaPreste is designed to cull the numbers of green crabs, a species that is not native to New England. Local shellfish harvesters are being paid to remove the green crabs, which are too small to be commercially viable as seafood. The program is funded out of fees the town collects for commercial shellfishing licenses.

The green crabs eat shellfish seedlings as well as eelgrass, which provides habitat for oysters and other shellfish.

“We know that they eat juvenile shellfish, and that they burrow into the marsh, which kind of makes the marsh fall apart,” LaPreste said.

As of early September, fishermen had harvested 33,000 pounds of the green crabs, according to LaPreste. The crabs are either saved for bait or donated to an Ipswich farm run by the Trustees of Reservations, where they are used as fertilizer.

“What we’d like to see, little by little, is the loads of crabs not coming up so quickly, and then we’ll know that we’re really putting pressure on them,” LaPreste said. “We haven’t seen that yet.”

The green crabs are edible, he said, but there is no real market for them because it takes about nine of them to make a pound.

Four neighboring municipalities – Gloucester, Essex, Rowley and Newbury – are working with Ipswich to advocate for controlling the green-crab population. On Sept. 18, Sen. Bruce Tarr of Gloucester and Rep. Brad Hill of Ipswich filed a bill to provide $133,000 for the effort.Ipswich program aims to cull out invasive crabs