Legal challenges being brought by environmentalists here against the Government over its inability to protect nature will be brought to an abrupt halt in the event of a no-deal Brexit, experts have warned.
Lawyers in Brussels are investigating Lough Neagh and Lough Beg, the largest wetlands in these islands and home to resting whooper swans.
Frustrated after failed attempts to block roads being built through swan nesting grounds or the burning of bogs to create shooting estates, local groups have turned to Europe for its help.
Campaigners have exhausted all other routes to oppose a planned road through Lough Beg's floodplain and controversial sand mining taking place on Lough Neagh.
Given its designation as a special protected area under EU law, they were able to take their case to the commission.
Now, with the case in the balance, they fear time has run out with Brexit due at the end of March.
"A no-deal means no access to a complaints procedure that could be all that stands between this area being the jewel of Northern Ireland's crown or a desecration of a unique landscape," said James Orr, director of Friends of the Earth Northern Ireland.
As part of its "green Brexit", the Government plans to create a new body to replace the commission and the European Court of Justice (ECJ).
If commission recommendations do not persuade a nation to make changes, the case will pass to the ECJ as the final arbiter, which does have the power.
But with exit day only two months away experts think there will be little political will from either European or British authorities to continue ongoing proceedings if there's a no-deal.
"I don't see why first the commission would keep on spending time and effort on these cases, and second why the UK Government would listen if anything came out of them," said Dr Viviane Gravey, an expert in EU environmental policy at Queen's University Belfast.
A European Commission spokesman confirmed that while legal proceedings would be brought to a conclusion under the withdrawal agreement, it could not speculate about a no-deal scenario.
Dr Gravey said owing to the bad Press the commission and the ECJ tend to get in the UK, there is unlikely to be any political fallout for the Government in ignoring their rulings.