The Solent and Southampton Water is located in one of the only major sheltered channels in Europe, lying between a substantial island (the Isle of Wight) and the mainland, on the south coast of England. It stretches from Hurst Spit to Hill Head across Hampshire, and on the north coast of the Isle of Wight from Yarmouth to Whitecliff Bay (Joint Nature Conservation Committee (JNCC), 2017).
This area is a complex major estuarine system consisting of coastal plain estuaries including the Yar, Medina, King’s Quay Shore, and the Hamble. Bar-built estuaries including Newtown Harbour and Beaulieu also occupy the Special Protection Area (SPA). The Solent and its inlets are unique in Britain and Europe for their unusual tidal regime, including double tides and long periods of tidal stand at high and low tide (English Nature (EN), 2005).
The Solent and Southampton Water is composed of extensive intertidal mudflats and sandbanks, inter- and subtidal rock, areas of saltmarsh, coastal lagoons, coastal reed beds, shingle banks, and grazing marsh.
Estuarine sediments within the site support rich populations of invertebrates that provide an important food source for wintering birds. The Solent as a whole exceeds 90,000 waders annually and the mudflats, coastal lagoons, shingle and saltmarsh provide vital feeding and roosting grounds for these. The shingle banks also provide important breeding grounds for terns. The Solent also supports 10-13% of world’s population of dark-bellied Brent geese, and 30% of the UK population (Stillman et al., 2009). Besides using the mudflats and grazing marshes to feed, they also rely on farmland with cereals and pasture, and amenity grasslands outside the SPA boundary (King, 2010).