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Coastal

The dynamic scenery of the British coastline comprises spectacular cliffs, beautiful sandy beaches and dunes, and dramatic rocky shores which provide a variety of habitats to some of our most unusual plants.

Golden seaweeds highlight the shoreline, brightly coloured lichens add splashes of colour to rocks and cliffs and the salt marshes are brought to life by the bright pink and purple of thrift and sea aster.

At over 11,000km in length, the coastline of our mainland alone is ten times longer than its apparent length due to the intricate pattern of inlets, estuaries and rock outcrops. This is in addition to the multitude of offshore islands, including 790 in Shetland, Orkney, Inner Hebrides and Outer Hebrides.

Our native coastal flora is directly exposed to the harsh salt-laden winds that blow in from the sea. It is in fact the severity of the environment that unifies the species found across these wide ranging habitats - a tolerance of sea salt, an ability to hold fast in the face of strong winds and crashing waves, and the capacity to withstand a constantly changing environment, have all shaped the resilient plants that grow here.

Habitat features

Cliff faces

Plants survive in the most unlikely places, clinging to crevices and ledges in one of the harshest environments along the coast. Rock samphire and golden samphire are two plants characteristic of cliffs, where their long tap-roots find a foothold in cracks and crevices in the rock.

Cliff top heaths

These harbour a number of species confined to the coast. The Scottish primrose is found at the very north-eastern tip of Scotland and nowhere else in the world. As well as the harsh weather conditions this plant faces, it is also threatened by climate change - inhabiting the most northern part of our Island means that it cannot migrate northwards in search of cooler pastures should temperatures rise. The ciliate strap lichen, is a bizarre looking lichen easily identified by its black hairs, and which grows in a handful of sites in western England and Wales. This species reaches the northern-limit of its distribution on Anglesey and is also found southwards to Cornwall and the Isles of Scilly. It was more widespread in the past, including lowland inland sites, but has been lost from many sites in southern England.. For this species, the effects of climate change may mean that the British populations become more important as distribution within Europe shift northwards, making it even more important to ensure a future for our populations.

Sand dunes

Within the rolling dunes, marram grass stabilises shifting sands and produces a habitat for sea-holly, centaury, pyramidal orchid and vipers bugloss whereas newly formed dunes and blow outs provide a habitat for ephemeral species such as the beautiful petalwort, one of our most delicate looking plants as well as the fen orchid.

Machair

A very special coastal habitat and one of the rarest in Europe, found only in the north and west of Scotland and Ireland. Almost 50% of Scottish machair occurs on the Outer Hebrides, where the best examples are on the Uists and Barra. The machair is surprisingly rich in flowers: up to 45 species can be found in any 1 square metre. It is this diversity of flowers that gives the machair its spring and summer colour. Key threats to the machair include climate change and dune erosion.

Shoreline

Along the craggy shoreline seaweeds flourish. Attaching themselves to the seabed they are at the mercy of the tides with many species becoming fully exposed at low tide, revealing their reds, greens and golds to us in all their glory. Off shore kelp beds, for example, are vital defences against storms, dissipating wave energy before it hits our shores. The length and diversity of habitats along our coast mean that the British Isles have an amazing variety of seaweeds. One of our rarest is sealoch egg wrack, or wigwrack, which is an unusual form of the more common eggwrack and which grows only in extremely sheltered sea lochs in North-west Scotland and Ireland. It is under threat from habitat loss and climate change.

Shingle beaches

Plants live a precarious existence amid shifting ridges of pebbles. Plants surviving here tend to be hardy perennials that are well adapted to the unstable substratum such as the waxy leaved sea kale, sea campion and the much rarer sea pea and oysterplant.

Salt marsh

Perhaps one of the most difficult of all coastal environments, being exposed to silt laden salty water twice a day. Well adapted species such as small cord-grass however form large mats which perform an important role in shore stabilization and sedimentation, trapping silty deposits that would otherwise be washed out to sea. The long-stalked glasswort, is useful for a different reason, once commonly collected and eaten as “samphire”. This tradition has seen a recent resurgence with samphire now being served in restaurants, often with spring lamb and fish.

Key issues

Coastal plants are threatened by a loss of habitat due to:

• Tourism.
• Sea defences.
• Climate change causing increased temperatures, increased storm damage and sea-level rise.
• Being smothered by invasive plants.
• Lack of correct management.

What we are doing

Our Important Plant Area (IPA) network includes a number of coastal sites that have been identified due to the rare plants and plant assemblages that inhabit them. These sites are in need of survey, research, expansion and management to ensure that they continue to support the plants for which they have been identified. For example:

• At Sefton Coast in Merseyside, Plantlife has been working on the dune systems to monitor the fate and understand the ecology of the rare bryophytes and liverworts that occur there (including Bryum sp. and Petalophyllum ralfsii).
• On the Lizard peninsular in Cornwall, Plantlife has implemented an extensive scheme to manage the expanding carpet of Hottentot fig on the coastal cliffs. Hottentot fig is an invasive species from South Africa.
• There are 5 IPAs identified for their machair communities in Scotland. On Colonsay, Plantlife is working with local volunteers and land owners to monitor the machair flowers, including orchids, and to improve management for them.
• Our Important Plant Areas for Algae project (undertaken in association with the Natural History Museum and the British Phycological Society) has identified our most important areas for both freshwater and marine algae (including the seaweeds) in the UK. Top sites include Skomer Island, Lundy Island, Falmouth and Helford in Cornwall and the Isle of Cumbrae.