PACKING SHED MARSH
Formerly a centre for grading and packing oysters for export to London and Europe in the 19th century, the island is essentially a series of oyster pits running perpendicular to the shoreline.
It underwent a 35% loss of marsh from its margins between 1888 and 1997. The shells of tons of slipper limpets cleared from the adjacent oyster beds in the 1930s and 1940s have helped to sustain the island, along with sand outwash forming a protective beach around the southernmost fringes.
A further 13% decrease around the marsh perimeter occurred between 1997 and 2014. This is in part due to the shells and recharge overwashing the oyster pits in response to storm events. A combination of a south wind and the flood tide moving into the fleets either side of the island has pushed the recharge shoreward over its centre and around the eastern and western margins, where the 1888 shoreline has been redefined.
Brushwood fences failed to check the movement of the recharge, due to lack of maintenance. The shells and gravels have formed a defensive ridge around the interior and have been stabilised by shrubby sea-blite, perennial glasswort and maritime grasses on the crest and slopes. The saltmarsh is otherwise mostly confined to the banks of the oyster pits which support both pioneer and perennial species, the latter including golden samphire.
The yellow area on the picture shows the proposed recharged site.