Outside estuaries there are muddy sediments wherever there is sufficient shelter from wave action, such as behind islands or towards
the top of extensive intertidal flats. At first glance, sandy or muddy shores appear relatively devoid of marine life. However, beneath the
surface are animals adapted to life in the sediment. Mudflats support rich invertebrate communities, which provide an important food source
for wading birds and fish. Surface plants such as sea grass or seaweeds such as gutweed Enteromorpha spp, help to stabilise the sediment, reduce erosion, and provide food for large numbers of birds such as Brent geese. Sandy beaches are characteristic of much of the coast of England, either covering the whole beach, or as a limited area of the shore alongside other habitats such as shingle or rock. Sand, rather than mud, is deposited where there is greater wave exposure, or lack of fine sediment input, so that only the larger sediment grains are deposited on the shore. Many sandy beaches are highly mobile, with sand being removed by winter storms, and re-deposited in early summer. Some changes can take place over longer timescales: for example sand can appear one year, disappear for a while, then reappear some years later. Plants are unable to survive on highly mobile sandy beaches. However a specialised community of sand hoppers can survive on the upper shore, while surf clams, razor shells and heart urchins can thrive towards the bottom of the shore. Towards the top of the shore, the coarse grained sediment dries quickly as the tide goes out,  aking it a difficult place for marine animals to survive. However, the dry sand may be blown to develop sand dunes above the high tide mark. With increasing shelter, finer sediments are deposited, consisting of a mixture of sand and mud. These mixed muddy-sand sediments contain
probably the most varied marine sediment communities, with the most diverse being in muddy gravels, although the sheer number of individuals is higher on mudflats. Muddy sands are characterised by diverse communities of worms such as lugworm and ragworm, along with shells such as Baltic tellins.

Muddy and sandy beaches are subject to a range of threats and disturbances. On specific sites activities such as bait digging, if carried out at critical times, or to a great extent, can cause major disturbance and damage to wildlife. Similarly, disturbance by recreational walkers or
dogs at critical times can disturb bird populations, forcing them to feed in other locations or at other times of the day which are less favourable. Shifting patterns in recreational activity, such as an increase in kite flying or buggy riding, will increase this disturbance. Mobile coarse sand beaches are less prone to damage and disturbance as they are naturally disturbed by wave action. Large changes to beach
structure and sediment supply can result from coastal defence works, or
sediment extraction elsewhere. Solid coastal defence structures at the top of sandy beaches may cause wave energy to be reflected back onto the beach, eroding sediment and lowering beach levels. This leads to even more wave energy reaching the sea defences, more energy being reflected back, and further lowering of beach levels until in many cases the sea defences are undermined, or the sand disappears from the beach entirely. Sand extraction continues at a number of beaches, such as the Ribble Estuary in north-west England.

The nature of rocky shores depends greatly on their geology and wave exposure. Hard rocks such as granite erode slowly and have fewer crevices and pools than rocky shores of slate or shale. Chalk shores occur around Flamborough, Norfolk, Kent, Sussex, the Isle of Wight and Dorset, and are extremely rare
throughout Europe. England has around 57% of the European
coastal chalk11, and contains many of the best examples of chalk shore habitats. Because chalk is soft and erodes easily, it supports an unusual collection of plants and animals, including shells and sponges that bore into the rock, and green seaweeds that are found on no other rock types.

All rocky shores show a zonation of plant and animal communities. At the top of the shore, only plants and animals that can cope with drying for up to 10 hours survive. These include maritime lichens, seaweeds such as channelled wrack, and animals such as the small periwinkle, which can hide away in crevices. Lower on the shore, plants and animals are not uncovered for such a long time at low tide, so a wider range of species are present including bladder wrack, egg wrack, anemones, limpets and a range of periwinkles and topshells. Towards the bottom of the shore, which the tide only exposes for around two hours at a time, plants and animals more typical of the shallow underwater environment can gain a foothold. These include the kelps, a range of sponges and seasquirts, and often fish such as blennies and gobies under boulders or within crevices. The typical zonation pattern can be changed by a number of factors. Rockpools allow different plants and animals to colonise the shore, crevices and fissures provide damp hiding places, and the under surfaces of boulders can be colonised by a range of starfish, urchins, seasquirts and sponges.

Rocky shores are generally robust, and suffer little from human activities such as recreation or disturbance. Some heavily visited sites suffer disturbance from excessive rockpooling, or turning of boulders to search for marine life49. Such high levels of disturbance are a cause for concern at some locations. More concerning is the destruction of particular rocky shore communities by developments such as coastal defences, or intertidal structures such as slipways and jetties. Many of the specialised upper shore and splash zone seaweed communities on chalk shores have been covered by concrete sea defence structures. Elsewhere, a proliferation of small-scale developments are resulting in a continual loss of natural foreshore.

Rocky shores adjacent to ports, harbours and marinas are still impacted by tributyltin (TBT) antifouling paint, with dogwhelks being either completely absent, or reduced to extremely low numbers. Rocky shores have been shown to be very sensitive to climate change, with a balance between northern (cold water) or southern (warm water) species of barnacles, limpets and topshells. Monitoring of these changes, is being undertaken by MarClim, a four year consortium-funded project led by the Marine Biological Association of the UK, which will give a measure of the way climate change is affecting marine wildlife.