Federal regulators say they have approved a change to fishing rules that will allow Maine and Massachusetts scallop fishermen opportunities to fish in state waters.

An arm of the National Oceanic and Atmospheric Administration says both states qualify for a program called the State Waters Scallop Exemption Program. The program allows some fishermen who are permitted to fish in federal waters to harvest scallops in state waters.

NOAA says allowing Maine and Massachusetts into the program would have “no adverse impact” on the effectiveness of federal scallop management.

Massachusetts is by far the most productive scallop producing state in the country, with harvesters bringing more than 21 million pounds of the shellfish to land in 2015. Maine’s fishery is much smaller but about as valuable on a per-pound basis.