Scilly's Nature Designations SSSI's Big Pool & Browarth, St Agnes Size: 9.33 hectares % of total area of SSSI's: 2.3% Designated features: Flowering plants General Description Big Pool and Little Pool are the only areas of open water on St Agnes. Both are freshwater pools, with abundant Fennel Pondweed oxygenating them. However, the frequent winter storms that breach the sea defences increase the salt water content of the pools, which is reflected by the presence of species such as Saltmarsh Rush and Sea Club-rush around the pool margins. The adjacent wet grassland is species rich with several species of clover including Western, Red and Subterranean Clover. The grassland also supports a population of Small Adder’s-tongue, Autumn Lady’s-tresses and the nationally rare Early Meadow-grass. Further afield the strandline beyond the sea defences support species such as Sea Radish, Sea Kale and both Frosted and Babington’s Orache. Here you will find the occasional breeding Ringed Plover along the beach, whilst during the winter you may find ducks such as Wigeon feeding within the grassland and Pochard on the pools. Practical Management Control of encroaching Bracken and Bramble, along with late summer grazing is the emphasis of management to maintain the diverse flora of the site. Management will also include the removal of Pittosporum trees that have established themselves on the carns to the north-east to prevent the spread of these invasive non-native shrubs into the grassland.