AUGUSTA — Maine fishing regulators are shutting down more key scallop grounds as fishermen exceed targeted levels for the year.

The state Department of Marine Resources says it is closing Cobscook Bay, the most productive scallop fishing area in Maine. It is also shutting down the Owls Head area of Lower Penobscot Bay and limiting the St. Croix River to one day per week for draggers and one day per week for divers.

The closures go into effect on Saturday. The state uses the closures to protect the scallop population. The scallops were valued at $12.78 per pound at the dock in 2014, a record according to state data. Maine scallops were worth almost $7.5 million last year — the most since 1993.