Rocky shore

A rocky shore is an intertidal area of seacoasts where solid rock predominates. Rocky shores are biologically rich environments, and are a useful "natural laboratory" for studying intertidal ecology and other biological processes. Due to their high accessibility, they have been well studied for a long time and their species are well known.[1][2]

Friendly Beaches 1
The rise and fall of tides on a rocky shore can define a volatile habitat for marine life
Lanzarote 4 Luc Viatour
Rocky shore in Lanzarote, Spain
Lanzarote 3 Luc Viatour
Rocky beach in Canary Islands
Valuga Beach
Rocky shore in Batanes, Philippines
Ocean from Leblon
Rocky shore in Leblon, Brazil

Marine life

There are a large number of factors that favour the survival of life on rocky shores. Temperate coastal waters are mixed by waves and convection, maintaining adequate availability of nutrients. Also, the sea brings plankton and broken organic matter in with each tide. The high availability of light (due to low depths) and nutrient levels means that primary productivity of seaweeds and algae can be very high. Human actions can also benefit rocky shores due to nutrient runoff.

Despite these favourable factors, there are also a number of challenges to marine organisms associated with the rocky shore ecosystem. Generally, the distribution of benthic species is limited by salinity, wave exposure, temperature, desiccation and general stress. The constant threat of desiccation during exposure at low tide can result in dehydration. Hence, many species have developed adaptations to prevent this drying out, such as the production of mucous layers and shells. Many species use shells and holdfasts to provide stability against strong wave actions. There are also a variety of other challenges such as temperature fluctuations due to tidal flow (resulting in exposure), changes in salinity and various ranges of illumination. Other threats include predation from birds and other marine organisms, as well as the effects of pollution.

Ballantine Scale

The Ballantine Scale is a biologically defined scale for measuring the degree of exposure level of wave action on a rocky shore. Devised in 1961 by W. J. Ballantine, then at the zoology department of Queen Mary College, London, U.K., the scale is based on the observation that where shoreline species are concerned "Different species growing on rocky shores require different degrees of protection from certain aspects of the physical environment, of which wave action is often the most important." The species present in the littoral zone therefore indicate the degree of the shore's exposure.[3] The scale runs from (1) an "extremely exposed" shore, to (8) an "extremely sheltered" shore.


Tidal movements of water creates zonation patterns along rocky shores from high to low-tide.[4] The area above the high-tide mark is the supralittoral zone which is virtually a terrestrial environment. The area around the high-tide mark is known as the intertidal fringe. Between the high and low-tide marks is the intertidal or littoral zone. Below the low-tide mark is the sublittoral or subtidal zone. The presence and abundance of different animals and algae vary in different zones along the rocky shore due to differing adaptations to the varying levels of exposure to sun and desiccation along the rocky shore.


Rocky shores are exposed to many forms of pollution, in particular pollution related to oil spills. Prominent spills are the Torrey Canyon spill,[5] The Amoco Cadiz spill outside the Brittany coast in France[6] and the Exxon Valdez spill in Prince William Sound, Alaska, USA. Garbage such as plastics and metals being left behind by people is also a problem among many rocky coastlines that attract tourists.

See also


  1. ^ J H Connell, Community Interactions on Marine Rocky Intertidal Shores. 1972. Annual Review of Ecology and Systematic Vol. 3: 169-192
  2. ^ J. Harrison Stark (1964). The Ecology of Rocky Shores. English Universities Press, London.
  3. ^ Ballantine (1961) page 1.
  4. ^ Adam, Purcell. "Rocky Shore". Basic Biology.
  5. ^ Southward, AJ and Southward, EC. 1978. Recolonization of Rocky shores after the use of toxic dispersants to clean up the Torrey Canyon spill. J. Fish. Res. Board. Can 35:682-706.
  6. ^ Seip,KL. 1984. The Amoco Cadiz Oil spill- at a glance. Mar. Poll. Bull. 15 (6) 218-220

Further reading

  • Cruz-Motta J. J., Miloslavich P., Palomo G., Iken K., Konar B., et al. (2010). "Patterns of Spatial Variation of Assemblages Associated with Intertidal Rocky Shores: A Global Perspective". PLoS ONE 5(12): e14354. doi:10.1371/journal.pone.0014354.
Ballantine scale

The Ballantine scale is a biologically defined scale for measuring the degree of exposure level of wave action on a rocky shore. Devised in 1961 by W. J. Ballantine, then at the zoology department of Queen Mary College, London, the scale is based on the observation that where shoreline species are concerned "Different species growing on rocky shores require different degrees of protection from certain aspects of the physical environment, of which wave action is often the most important." The species present in the littoral zone therefore indicate the degree of the shore's exposure.

Bongoyo Island

Bongoyo Island (or simply Bongoyo) is an uninhabited island in Tanzania, situated 2.5km north of the country's largest city, Dar es Salaam. It is the most frequently visited of the four islands of the Dar es Salaam Marine Reserve (DMRS) and a popular daytrip for both tourists and Tanzanian residents alike for snorkelling and sunbathing.

The island lies close to the Msasani Peninsula (in the Kinondoni district of the city) and is reachable by means of a 30-minute boat ride from the mainland. The point of departure for most visitors to the island is 'The Slipways' hotel complex on the western side of the Msasani Peninsula.

The island has a very rocky shore and only two beaches. All visitors visit the beach at the northwestern tip of the island, where the boats moor and where there are some huts, drinks and food. The much longer but narrower beach along the northeastern side has no facilities and is mostly deserted. The entire island (apart from the beaches) is covered in dense forest and has a few walking trails, so only a few people venture there. The terrain is somewhat treacherous with sharp rocks. In the middle of the island one finds the remains of a German colonial building at 6°42′8.48″S 39°16′11.49″E, clearly visible on Google Maps. The Indian Ocean has penetrated the northern shore of the island, creating a tidal lagoon along whose shores there are some mangroves.

Chek Jawa

Tanjong Chek Jawa (or Tanjung Chek Jawa or simply Chek Jawa) is a cape and the name of its 100-hectare wetlands located on the south-eastern tip of Pulau Ubin, an island off the north-eastern coast of the main island of Singapore. Chek Jawa is among the last few places left in Singapore with a natural rocky shore.

The wetlands are unique as several ecosystems can be observed in one area – sandy beach, rocky beach, seagrass lagoon, coral rubble, mangroves and coastal forest. The site forms part of the Ubin–Khatib Important Bird Area (IBA), identified as such by BirdLife International because it supports significant numbers of visiting and resident birds, some of which are threatened.In December 2001, the government called off reclamation plans of the Chek Jawa area after a biodiversity survey conducted by conservationist volunteers. State use of the land will be deferred for the next 10 years. However, Chek Jawa may still be re-used by the government in and after 2012.

Corallina officinalis

Corallina officinalis is a calcareous red seaweed which grows in the lower and mid-littoral zones on rocky shores.

It is primarily found growing around the rims of tide pools, but can be found in shallow crevices anywhere on the rocky shore that are regularly refreshed with sea water. It predominantly grows on the lower shore, especially where fucoid algae are absent, but is also found further up shore on exposed coasts.

It forms calcium carbonate deposits within its cells which serve to strengthen the thallus. These white deposits cause the seaweed to appear pink in colour, with white patches where the calcium carbonate is particularly concentrated, such as at the growing tips. The calcium carbonate makes it unpalatable to most rocky shore grazers.

Costa da Morte

Costa da Morte (Galician pronunciation: [ˈkɔstɐ ðɐ ˈmɔɾtɪ]; Spanish: Costa de la Muerte; "Death Coast") is part of the Galician coast. The Costa da Morte extends from the villages of Muros and Malpica.

The Costa da Morte received its name because there have been so many shipwrecks along its treacherous rocky shore. The shore of the Costa da Morte is exposed directly to the Atlantic Ocean. It is an area that has suffered a number of oil spills, including the spill from the Prestige in 2002.

The exterior cape region is known for anthropological, historical and geographical reasons. Its name in the Galician language is Fisterra, which descends from the Roman legend which held that this area was the end of the world (Finis-terrae). The area was largely Christianized by the Catholic Church with the aid of a large flux of Christian pilgrims arriving on the Way of St. James.

The people of the area still preserve pre-Christian ritual places and pass on some of the traditional beliefs. For example, there are giant pedras de abalar (i.e. "oscillating stones", the common term in English is rocking stone) throughout the region. These pedras de abalar were sacred locations and used in various rituals that are remembered in local culture. There is also a local legend that the wind creates wild nightmares.

Curries Woods

Curries Woods is a neighborhood in the southern part of Greenville in Jersey City, New Jersey bordering Bayonne. It was named after James Curie, who was on the town Committee for Greenville when it was its own Township in the 19th century. The area remained rural until the later part of the century when the Central Railroad of New Jersey built a line connecting ferries to Elizabeth, New Jersey and New York City. Currie's Woods still remained untouched through the late part of the century and it was valued for its woods, rocky shore and dunes on Newark Bay. A lot of the land was eventually lost, but a tract was set aside in the early part of the 20th century. A small cemetery, the Old Greenville Cemetery, was nearby. This park lost much of its land to the city's largest Housing Authority project in 1959, except a small tract in Bayonne, Mercer Park.

Intertidal ecology

Intertidal ecology is the study of intertidal ecosystems, where organisms live between the low and high tide lines. At low tide, the intertidal is exposed whereas at high tide, the intertidal is underwater. Intertidal ecologists therefore study the interactions between intertidal organisms and their environment, as well as between different species of intertidal organisms within a particular intertidal community. The most important environmental and species interactions may vary based on the type of intertidal community being studied, the broadest of classifications being based on substrates—rocky shore and soft bottom communities.Organisms living in this zone have a highly variable and often hostile environment, and have evolved various adaptations to cope with and even exploit these conditions. One easily visible feature of intertidal communities is vertical zonation, where the community is divided into distinct vertical bands of specific species going up the shore. Species ability to cope with abiotic factors associated with emersion stress, such as desiccation determines their upper limits, while biotic interactions e.g.competition with other species sets their lower limits.Intertidal regions are utilized by humans for food and recreation, but anthropogenic actions also have major impacts, with overexploitation, invasive species and climate change being among the problems faced by intertidal communities. In some places Marine Protected Areas have been established to protect these areas and aid in scientific research.

Intertidal zone

The intertidal zone, also known as the foreshore or seashore, is the area that is above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species of life, such as starfish, sea urchins, and many species of coral. Sometimes it is referred to as the littoral zone, although that can be defined as a wider region.

The well-known area also includes steep rocky cliffs, sandy beaches, or wetlands (e.g., vast mudflats). The area can be a narrow strip, as in Pacific islands that have only a narrow tidal range, or can include many meters of shoreline where shallow beach slopes interact with high tidal excursion. The peritidal zone is similar but somewhat wider, extending from above the highest tide level to below the lowest.

Organisms in the intertidal zone are adapted to an environment of harsh extremes. The intertidal zone is also home to several species from different phyla (Porifera, Annelida, Coelenterata, Mollusca, Arthropoda, etc.). Water is available regularly with the tides, but varies from fresh with rain to highly saline and dry salt, with drying between tidal inundations. Wave splash can dislodge residents from the littoral zone. With the intertidal zone's high exposure to sunlight, the temperature can range from very hot with full sunshine to near freezing in colder climates. Some microclimates in the littoral zone are ameliorated by local features and larger plants such as mangroves. Adaptation in the littoral zone allows the use of nutrients supplied in high volume on a regular basis from the sea, which is actively moved to the zone by tides. Edges of habitats, in this case land and sea, are themselves often significant ecologies, and the littoral zone is a prime example.

A typical rocky shore can be divided into a spray zone or splash zone (also known as the supratidal zone), which is above the spring high-tide line and is covered by water only during storms, and an intertidal zone, which lies between the high and low tidal extremes. Along most shores, the intertidal zone can be clearly separated into the following subzones: high tide zone, middle tide zone, and low tide zone. The intertidal zone is one of a number of marine biomes or habitats, including estuary, neritic, surface, and deep zones.

Labrador Nature Reserve

Labrador Nature Reserve (Chinese: 拉柏多自然保护区, Malay: Kawasan Simpanan Alam Semulajadi Labrador), also known locally as Labrador Park (拉柏多公园, Taman Labrador), is located in the southern part of mainland Singapore. It is home to the only rocky sea-cliff on the mainland that is accessible to the public. Since 2002, 10 hectares of coastal secondary-type vegetation and its rocky shore have been gazetted as a nature reserve and its flora and fauna preserved by NParks.

Mackworth Island

Mackworth Island is an approximately 100-acre (40 ha) island in Falmouth, Maine, USA, adjacent to its border with Portland, Maine. In 1631, Sir Ferdinando Gorges gave the island to Arthur Mackworth, his deputy in Casco Bay, and the island has retained his name. There is a causeway connecting the island to the mainland in Falmouth. Visitors to the island must pass by a tollhouse; cars can enter the island but parking is limited. There is a footpath around the perimeter of the island with views of Falmouth, Portland, and other islands surrounding the bay. The island is heavily wooded. One portion of the woods is dedicated to “Fairy Houses” which are constructed by visitors using natural materials found on the island. Mackworth Island has a beautiful rocky shore and offers ample opportunities for surf fisherman of Bluefish and Stripers.


Mirca (population 321) is a town on the north side of the island of Brač in Croatia. Administratively it is part of the city of Supetar.

People on Brač, and in Mirca, used to be into commercial fishing and typical Mediterranean agriculture (vineyards and wine; almonds; olive oil and such). In the last few decades the tourism industry took over, and a lot of people built houses with apartments and rooms to rent to the summer tourists. Many “outside” people built vacation and summer houses along the shores. In general, Mirca is rather a quiet place.

Mirca was originally positioned around half a mile inland and now spreads to the sea; thus, there is an “upper” Mirca and a “lower” Mirca. There is a small harbor and a crescent shaped pebble beach. On the eastern side of the beach, there was formerly the restaurant, “Gumonca”, and the western side ends in a flat rocky shore with the pine woods reaching the sea.


Muxía (Galician pronunciation: [muˈʃi.ɐ]) is a coastal town and municipality in the province of A Coruña in the autonomous community of Galicia in northwestern Spain. It belongs to the comarca of Fisterra. It is one of the final destinations for pilgrims on the Way of St. James after visiting the shrine of the apostle Saint James the Great in Santiago de Compostela.

Muxía is known for its beaches. It has an active fishing industry.

Muxía is part of the 'Costa da Morte' or 'Costa de la Muerte' (i.e., the "Coast of Death"). The Costa Da Morte was given this name because of the large number of shipwrecks along its rocky shore. The Costa Da Morte is one of the three regions of the Costa del Marisco, or "The Seafood Coast."

Muxía is 3 kilometers from a famous Benedictine monastery that is now used as a church, the Church of San Xulián de Moraime. The name of the town, "Muxía", refers to the monks who established this monastery. Another famous church in the area is the Santuario da Virxe da Barca which stands on a rocky ridge above the surf.

There are several locations along the Costa da Morte that have a "pedra de abalar", (i.e., an "oscillating stone"), or rocking stone. One of these is in Muxía, the "Pedra da Barca". These are large stones that are balanced on a point, so that they can be moved back and forth easily, or even wiggle in response to the wind. These were used at one time to determine the guilt or innocence of those accused of serious crimes.

There was a serious oil spill involving the oil tanker "Prestige" along the Muxía part of the coast in November, 2002, leaking about 70,000 gallons of oil into the Atlantic.

Northeaster (painting)

Northeaster is one of several paintings on marine subjects by the late-19th-century American painter Winslow Homer. Like The Fog Warning and Breezing Up, he created it during his time in Maine. It is on display in the Metropolitan Museum of Art in New York. Viewers are presented a struggle of elements between the sea and the rocky shore. Winslow Homer excelled in painting landscape paintings that depicted seascapes and mountain scenery.

Outer Brewster Island

Outer Brewster Island, also known as Outward Island, is one of the outer islands in the Boston Harbor Islands National Recreation Area and is situated some 10 miles offshore of downtown Boston. The island has a permanent size of 20 acres, and consists of exposed bedrock covered by fertile soil bounded by a rocky shore with steep cliffs. It provides a nesting habitat for coastal water birds, including cormorants, gulls, common eider ducks, glossy ibis and American oystercatchers. The birds are aggressive during their nesting season and access by humans, which is by private boat only, is discouraged during this period.

Like the neighboring islands of Great Brewster, Little Brewster and Middle Brewster, Outer Brewster Island is named after William Brewster, the first preacher and teacher for the Plymouth Colony. The relative barrenness and rocky shoreline of Outer Brewster has resulted in limited human usage. A granite quarry was operated on the island in the 19th century, and a coastal defense battery, known as Battery Jewell, was built on the island during World War II. Both are now disused and abandoned.In 1798 Nathaniel Austin bought Outer Brewster Island from David Wood for $400. Austin built an artificial harbor on the island and hoped to establish a profitable quarry. He built the house at 27 Harvard Square and 92 Main Street in Charlestown from stone mined on Outer Brewster.The island was acquired by the US government from a private owner in 1913. Its primary use was in World War II as part of the Brewster Islands Military Reservation for a long-range 6-inch gun battery, named Battery Jewell and completed in 1943 along with a radar station. The island was abandoned by the Army in 1947 and subsequently sold to a private owner, becoming a state park in 1973.In 2005, Virginia energy company AES Energy proposed placing a liquified natural gas terminal on the island. Political opposition from environmental, recreational and boating interests succeeded in preventing the proposal from moving forward.

St James, Cape Town

St James is a suburb of Cape Town, South Africa, situated on the False Bay coast between Muizenberg and Kalk Bay. The suburb is situated between the rocky shore and a steep mountain, and measures about 200m by 2 km. Its name derives from the early St James Catholic Church, built circa 1880. Most of the suburb was built between 1910 and 1950, after the railway line was built connecting Cape Town to False Bay.

St James beach is well known for its colourful Victorian-style bathing boxes, tidal pool and rock pools, which are popular with children.Most of the homes in the area date back to the days when the Cape was still a colony of the British Empire. The houses were built from limestone, plaster and stone, with traditional thatched roofs. St James Cottage was built in 1853 and during the Anglo-Boer War, the owner Abraham Auret helped to hide prisoners of war in the loft of his barn after which they attempted to escape across the bay.Boyes Drive runs above St James and provides scenic views of the False Bay coastline. St James is located on the Simon's Town train line and the Main Road that runs down the False Bay coast of the Cape Peninsula. There are walks and hikes on the mountains above the town, and whale watching opportunities during whale season.


Staffin (Scottish Gaelic: Stafain) is a district with the Gaelic name An Taobh Sear, which translates as 'the East Side', on the northeast coast of the Trotternish peninsula of the island of Skye. It is located on the A855 road about 17 miles (27 km) north of Portree and is overlooked by the Trotternish Ridge with the famous rock formations of The Storr and the Quiraing. The district comprises 23 townships made up of, from south to north, Rigg, Tote, Lealt, Lonfearn, Grealin, Breackry, Cul-nan-cnoc, Bhaltos, Raiseburgh, Ellishadder, Garafad, Clachan, Garros, Marrishader, Maligar, Stenscholl, Brogaig, Sartle, Glasphein, Digg, Dunan, Flodigarry and Greap.

The Kilmartin River runs northwards through the village. From where it reaches the sea a rocky shore leads east to a slipway at An Corran. Here a local resident found a slab bearing a dinosaur track, probably made by a small ornithopod. Experts subsequently found more dinosaur prints of up to 50 cm, the largest found in Scotland, made by a creature similar to Megalosaurus. At about 160 million years old they are the youngest dinosaur remains to be found in Scotland.A Mesolithic hunter-gatherer site dating to the 7th millennium BC at An Corran is one of the oldest archaeological sites in Scotland. Its occupation is probably linked to that of the rock shelter at Sand, Applecross on the coast of Wester Ross.In the modern era this part of Skye retains a strong Gaelic identity with 61 per cent of the local population recorded as speaking the language in 2001. In September 2010, Comunn na Gàidhlig named Staffin as their "Gaelic Community of the Year", in the first year this competition has run. Also in September 2010, Highland Council announced the launch of a consultation into a plan to convert the local primary into a Gaelic medium school. This would be the second such conversion in Scotland, after Bun-sgoil Shlèite. Only 5 out of the school's thirty pupils have English as their only language, with the remainder being bilingual English and Gaelic speakers.In 2011 it was reported that Staffin Island may be the last in Scotland where the old tradition of having cattle swim between grazings is still carried out. Crofter Iain MacDonald, who used to swim with the animals, now uses a boat to encourage them to swim from Staffin Island to Skye in early spring and back again in October.

Target Rock National Wildlife Refuge

The Target Rock National Wildlife Refuge is located just east of the village of Lloyd Harbor, New York, on the north shore of Long Island, 25 miles (40 km) east of New York City. It is managed by the U.S. Fish and Wildlife Service as part of the Long Island National Wildlife Refuge Complex.

The 80-acre (32 ha) refuge is composed of mature oak-hickory forest, a one-half-mile (0.80 km) rocky beach, a brackish pond, and several vernal ponds. The land and waters support a variety of songbirds (particularly warblers during spring migration), mammals, shorebirds, fish, reptiles and amphibians. During the colder months, diving ducks are common offshore, while harbor seals occasionally use the beach and nearby rocks as resting sites. New York State and federally protected piping plover, least tern, and common tern depend on the refuge's rocky shore for foraging and rearing young.

The spring bloom at Target Rock is a reminder of its days as a garden estate, with flowering rhododendrons and mountain laurel.

West Cape

West Cape is the westernmost point in the main chain of islands of New Zealand. It is located in the far southwest of the South Island, within Fiordland National Park, between Dusky Sound and Chalky Inlet.

West Cape is one of the 4 New Zealand Cardinal Capes named by James Cook, Commander of the Endeavour in the 1769-70 voyage. The other Cardinal Capes being named at the time North Cape, Cape East & Cape South .

West Cape is on a rocky shore and low forest-covered sloping land, just North of the Newton River Mouth.

Wolfe's Neck Woods State Park

Wolfe's Neck Woods State Park is a public recreation area located on Casco Bay on the southeastern side of Freeport, Maine. The state park occupies 244 acres (99 ha) on a narrow peninsula, Wolfe's Neck, that runs between Casco Bay and the Harraseeket River. It includes white pine and hemlock forests, salt marsh estuary, and rocky shore. The park is managed by the Maine Department of Agriculture, Conservation and Forestry.


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