There are 2 wetland sites on St Mary’s; both are SSSI’s and are very important not only for biodiversity but also to the very fabric of island life. They provide the majority of the drinking water supplies for St Mary’s as well as a flood defence to some key areas of habitation, economy and critical infrastructure. Through lack of management, increased growth of willow, bramble and bracken meant that by 2015 the wetlands were drying out and as a consequence were less effective as functioning wetland ecosystems.
The AONB partnership has helped to facilitate hydrological monitoring to take place within the wetlands to help us understand how they function and to enable a water level management plan to be drawn up. Ongoing dipwell and ecological monitoring now takes place alongside and a programme of rotational reed cutting and willow removal as part of the site management plan.
Since the onset of management ecological monitoring has revealed significant increases in nationally rare plants such as Tubular water-dropwort and the return of Marsh thistle and Lesser marshwort, both rare in Scilly-terms.