Plymouth Sound and Estuaries Special Area of Conservation (SAC) is located on the south coast of England and straddles the border between Devon and Cornwall. The SAC is a ria system with several marine inlets, including Plymouth Sound and its associated tributaries. The site is home to several nationally rare or scarce species, including red seaweed and stackhouse batters. It is also the only known spawning site for the allis shad.

Plymouth is a busy naval and commercial port, and management is needed to maintain the integrity of the site for nature. Like other estuaries, the pressures impacting upon it include commercial and naval shipping, commercial and recreational fishing and boating, as well as other water sports.

Plymouth. Photo credit Ocean Conservation Trust
Plymouth. Photo credit Ocean Conservation Trust

Plymouth Sound and Estuaries has been designated as a SAC for the estuarine and coastal features, including the wide-ranging mudflats and saltmarsh. These designated habitats are highly productive systems, forming a critical part of the food chain. They contain widespread and diverse infaunal communities rich in bivalves and other invertebrates and provide important feeding grounds for internationally important wildfowl. Notably, the only known natural population of the triangular club-rush in England is found on the Tamar.

Saltmarsh is an uncommon habitat in the south west of England and provides important roosting areas for birds. The site is home to communities of slender sea pens, fan mussels, and the nationally scarce tentacled lagoon worm. The saltmarsh fringes and seagrass act as nursery areas for commercially important juvenile bass.

The latest from this SAC


Seagrass, Isles of Scilly. Credit Michiel Vos/Ocean Image Bank

New boat mooring system paves way for significant seagrass rewilding

A pioneering project by the Marine Conservation Society and the Ocean Conservation Trust has recorded significant seagrass regrowth in Plymouth Sound, whilst continuing to allow safe boat mooring. Four years following the installation of a new ‘Advanced Mooring System’, the Marine Conservation Society and partners at the Ocean Conservation Trust report a 212% increase in…


Seagrass Superheroes Series 2022

What a Spring we have seen here on the ReMEDIES Project Education program!  As we head inexorably towards June and the start of Summer and a busy diving season, we can look back at the great successes of the Seagrass Superheroes program and our intensive educational outreach season delivering the series four times over thanks…

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