Sengekontacket Pond was reopened to shellfishing on Monday morning, after water testing came back negative for significant levels of bacteria. David Grunden, Oak Bluffs shellfish constable, said shellfishermen were back in the pond in search of quahaugs and steamers not long after the reopening.

The 745-acre pond shared by the towns of Edgartown and Oak Bluffs is loaded with shellfish. Shellfishermen have had limited access to the pond for months.

Sengekontacket Pond was closed to shellfishing through the summer because of concerns about water quality. Though water testing results indicated improved water quality through the summer, Mr. Grunden said, the state Division of Marine Fisheries still maintained a mandatory closure based on the previous year’s testing.

The pond closure was scheduled to end on Sept. 30; bad weather followed. When the pond was reopened on Oct. 1, it was open only for a few hours. State water tests taken earlier in the week came up with higher levels of bacteria. The pond was closed later in the day.

Water quality has since improved and the pond is back open again.