Developed with the help of Duck Unlimited, water control structures and dykes were constructed to stabilize and control water levels. The Missaguash Marsh was the first wetland developed, followed by the Tintamarre Complex in New Brunswick and the Amherst Point Sanctuary and East Amherst Marshes in Nova Scotia. Underlaid with marine silt, these marshes are extremely productive. Developed initially for waterfowl, many unusual and migratory non-game marsh birds live on these marshes. Other tern species seen in Nova Scotia are white in colour and are seen along the coastline.
Black terns are smaller than common and Arctic terns.
When breeding, their plumage, bill, head, and back are black. The wings and tail are various shades of grey. They seldom dive, preferring to pluck their food from the surface. Black terns build their nests upon floating piles of dead vegetation, such as cattails or bur-reeds, floating mats of muck, or similar materials. The nest consists of a small gathering of aquatic vegetation in a cup-like bowl.