A £1m study on protecting Strangford Lough's rich marine life could spark new safeguards around fishing, boating and diving in the waterway.
The research by Queen's University revealed the extent of the damage to horse mussel reefs.
Strangford Lough is designated as a Special Area of Conservation, and is one of only two marine nature reserves in Ireland, thanks in part to the abundance of reefs with horse mussels.
Surveys in 2003 showed the reefs had deteriorated and a ban on mobile fishing gear, involving trawling and dredging, was introduced by the Department of Agriculture (DARD).
A restoration plan was subsequently produced, committing DARD and the Department of Environment (DoE) to introduce protective measures.
Environment Minister Alex Attwood said: "For my part, I will introduce regulations to restrict anchoring of boats and diving in affected areas as soon as possible.
"I look forward to working with DARD in this regard."