Brackish Lagoons

Orford Ness contains one of the largest areas of unimproved brackish marsh in Suffolk within which coastal brackish lagoons are listed as a priority habitat on Annex 1 of the EC Habitats Directive (92/43/EEC) and are a key habitat within the UK and Suffolk Biodiversity Action Plans (BAPs).

In a national context the Alde-Ore complex, of which Orford Ness is part, is one of the richest sites for brackish lagoons. These brackish lagoons (pools with a mix of fresh and salt water) in Kings Marsh are mostly man-made structures. They were originally 'borrow pits' from where clay was 'borrowed' for use in the construction and repair of the river walls.

They are important because they support a small but significant group of unusual plants and animals, due to the fluctuations in the salt content of the water. Only very few species can tolerate these changing conditions and some of those present in these lagoons are nationally very rare. The presence of the Starlet Sea anemone (Nematostella vectensis), a species within the UK BAP, is noteworthy. The importance of this habitat is one reason why Orford Ness is a proposed Special Area for Conservation under European Directives.