Dorset’s habitats: the coast
The unique geology of the Dorset coastline is not only internationally famous but over its entire length it is also rich in wildlife, some of it unique to the county, reveals Colin Varndell
Published in February ’12
Starting at Lyme Regis a vast area of rock known as Broad Ledge is exposed at low tide. This is arguably one of Britain’s top rockpooling sites and is rich in seaweeds, crustaceans and other sealife. Between Broad Ledge and Charmouth, the stretch known as Black Ven and the Spittles is possibly the wildest, untamed place in Britain. This is due to the constant changing of the landscape as the ground shifts and great chunks of clay and rock spew down on the beach. Wild plants, which survive in this hostile wilderness, include scarlet pimpernel, common centaury, marjoram, selfheal, birdsfoot trefoil and marsh helleborine: a member of the orchid family. Teasels and Buddleia thrive here too, acting like a magnet to insects, especially butterflies like marbled white, green hairstreak, brimstone and various skippers.
To the east of here, the magnificent towering cliffs of West Bay and Burton Bradstock support a wide range of birdlife. The perpendicular sandstone escarpment of the east cliff gives the impression that the landscape has been sliced away. Within the face of the cliff, lateral seams of hard sandstone reveal how it remains so vertical in the face of extreme westerly fronts. In the summer months a wide variety of birds nest on these rock seams and in the crevices.
Ravens have nested on the east cliff for many years and are easily identified by their massive size (larger than a buzzard), wedge-shaped tail and their deep guttural calls. Herring gulls glide effortlessly along the cliff edge, riding the thermals on warm summer afternoons and great black-backed gulls and fulmar petrels may also be seen. The fulmar, which nests in hollows in the cliff face, is a fascinating bird to watch as it wheels and soars without ever seeming to move its stiffly held wings. To the east of Burton the cliffs give way to a more gentle landscape, which slopes down towards Cogden.
On a winter day the shingle beach at Cogden can seem bleak and lifeless, but come springtime this area erupts with a frenzy of life, as it becomes festooned with an array of wild flowers. Sweeping drifts of pink thrift and sea kale decorate the shingle, while patches of grass support ground-hugging plants like tormentil and spring cinquefoil. Closer to the shore succulent patches of sea sandwort sprawl across the pebbles.
The reedbeds of Cogden and Bexington literally heave with life in summer, and in winter up to 60,000 starlings congregate to roost in the reeds at dusk. Cogden is also an excellent place for observing reptiles in summer with four species being annually recorded here: adder, grass snake, common lizard and slow worm. The marsh frog also occurs here, and has been recorded in good numbers between Cogden and Bexington for the past few years.
At the Abbotsbury end of Chesil Beach there are some remarkable plants like biting stonecrop and sea pea, the latter is thought to be the most impressive example of the species in the country. As the beach curves towards Ferrybridge more unusual plants are found including the nationally rare purple broomrape. There is also a small breeding colony of little terns here. The unique limestone outcrop of Portland provides a landing stage for migrant birds in spring. The island supports a wealth of flora and fauna that flourish along the sea cliffs – and in the abandoned quarries – including unique races of rock sea-lavender, Portland Spurge and a sub-species of the silver-studded blue butterfly. The wall lizard has established strong colonies on the island and can be seen basking on stones in sheltered locations.
Kimmeridge is recognised mostly for its marine wildlife with its many ledges and rock pools. There is a wide variety of seaweeds, sea anemones and other invertebrates, along with the various fish and shellfish that inhabit the marine environment. In spring the cliffs around Kimmeridge are ablaze with colours of sea thrift, mingling with cushions of sea campion and sprays of the yellow umbellifer eastern rocket. On the rocks the primitive life-forms of barnacles and limpets are exposed at low tide, stuck fast to the limestone pavements. As the tide returns to submerge them, they once again become active and start to browse and move slowly over the rocks.
The early spider orchid is a national rarity, but here in Dorset it can be very common along the coast. Look for it in April between Langton Matravers and Dancing Ledge, where it can often be found by the thousand. The limestone cliffs from Durlston Head to St. Alban’s Head also support another national rarity with substantial numbers of early gentian in spring.
On the cliffs at Handfast Point there is an abundance of chalk-loving plants, such as crosswort, kidney vetch, pyramidal orchid, lady’s bedstraw, yellow-wort, marjoram, bladder campion, wild carrot and Nottingham catchfly. Greater knapweed is an irresistible magnet for many insects here, especially cardinal and longhorn beetles, as well as for a wide variety of butterflies. The Adonis blue, brown argus, Lulworth skipper and small blue all occur here in healthy populations. The Lulworth skipper is Dorset’s very own butterfly species and was first discovered at Durdle Door in 1832.
There is a cormorant colony on the near-vertical cliff face near to the two chalk stacks known as the Pinnacles. Peregrines often rest on these chalk stacks and in the past they nested on the triangular pinnacle.
On the dunes alongside Studland Beach all six native reptiles can be found including the internationally rare sand lizard. Poole Harbour is an internationally important place for migrant birds throughout the year. In winter the exposure of mudflats as the tide recedes supports a varied population of wading birds, as many species seek the relative warm climate of the south coast. Dunlin, oystercatcher, greenshank, curlew, redshank and black-tailed godwit are all present and the harbour now boasts one of the largest wintering colonies of avocets in Britain. Common and sandwich terns breed in Poole Harbour in summer and may be seen diving for sand eels near to the Studland ferry.
At the extreme eastern end of the Dorset coast, beneath Hengistbury Head, just beyond where the Stour and the Avon meet, lies Stanpit Marsh Nature Reserve. It is a low-lying area prone to flooding, so the wildlife here is mostly wading birds and wildfowl.
Living in Dorset, we are privileged to share a stretch of coastline with so many beautiful, sometimes rare, but always awe-inspiring creatures and plants. Long may our habitats continue to be so successful and sustainable.