Marine and coastal policy

EU Life-Nature Saline Lagoons Project

Lymington - Keyhaven Nature Reserve

The 18 hectares of lagoons at Lymington-Keyhaven Nature Reserve support a diverse and highly specialised fauna and flora, including rare species and are, thus, nationally important.

The lagoons also support nationally important breeding populations of little terns, Sterna albifrons (1.2% of UK total).

These lagoons are at risk from changes to their hydrology and salinity levels. Because flows of fresh water have increased, caused by nearby gravel extraction, salinity levels have fallen and some key species have declined. Predation threatens productivity of ground nesting birds (including little terns). Vegetation growth is a problem on tern nesting islands.

The ecology and hydrology of the site needs to be more fully understood to allow development of long-term solutions to the hydrological and water exchange problems within the site.

Actions to address threats

A full assessment of the hydrology and ecology of the lagoons, scientific assessment of the general condition of each lagoon, the salinity levels and the populations or conservation status of target species has been undertaken. The specialist consultants made recommendations on the measures required to secure the future condition of the lagoons.

These lagoons are at risk from changes to their hydrology and salinity levels

As a result, watercourses have been re-profiled so that water flow around the lagoon system is improved, helping salinity management. New sluices are being installed to balance water levels and salinity levels within the lagoons, and new watercourses dug to take surplus freshwater away from the lagoons.

An anti-predator fence has been installed around the lagoon to help ground-nesting birds.

Vegetation is regularly removed from the islands to maintain bare shingle, suitable for nesting terns, waders and wildfowl.

Invasive scrub that impedes access for visitors has been controlled.
A consultation process with the local community, user groups and other parties has been employed.