Concerns have been raised over the impact of the Ramsey Marina scheme on sea birds and other wildlife.
The Manx Wildlife Trust says the loss of habitats in the lower Sulby river area could reduce bird populations - and the variety of species nesting there.
The Harbours Division at the Department of Transport is considering a transformation of Ramsey Harbour - with a new tidal barrier and pontoons.
But the Trust's Director Duncan Bridges says a third of the Island's entire stock of certain habitats could be lost:
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