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

Queen Mary, University of London

Queen Mary, University of London is a public research university located in London, United Kingdom and a constituent college of the federal University of London...

, London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

, 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.

Abbreviated summary

An abbreviated summary of the scale is given below. The scale runs from 1) an "extremely exposed" shore, to 8) an "extremely sheltered" shore. The littoral zone generally is the zone between low and high tides. The supra-littoral is above the barnacle

Barnacle

A barnacle is a type of arthropod belonging to infraclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile suspension feeders, and have...

 line.

Scale unit	Name	Environment	Species
1	Extremely exposed	Continuous heavy surf	Infra-littoral: Alaria Alaria Alaria is a genus of brown alga comprising approximately 17 species. Members of the genus are dried and eaten as a food in Western Europe, China, Korea, Japan , and South America 17:56, 1 August 2010...  dominant; Mid-littoral:Himanthalia Algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many... , Gigurtina, Chthalamus dominant Supra-littoral: dense Porphyra Porphyra Porphyra is a foliose red algal genus of laver, comprising approximately 70 species. It grows in the intertidal zone, typically between the upper intertidal zone and the splash zone in cold waters of temperate oceans. In East Asia, it is used to produce the sea vegetable products nori and gim ,... , lichens abundant
2	Very exposed	"Workable only on calm days"	Infra-littoral: Alaria Alaria Alaria is a genus of brown alga comprising approximately 17 species. Members of the genus are dried and eaten as a food in Western Europe, China, Korea, Japan , and South America 17:56, 1 August 2010...  less frequent to common, Laminaria digitata Laminaria digitata Laminaria digitata is a large brown alga in the family Laminariaceae, also known by the common name Oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean.-Description:...  dominant Mid-littoral: scattered Himanthalia Algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many... , Gigurtina; Chthalamus abundant and dominant; Balanus balanoides frequent to common Supra-littoral: scattered Porphyra Porphyra Porphyra is a foliose red algal genus of laver, comprising approximately 70 species. It grows in the intertidal zone, typically between the upper intertidal zone and the splash zone in cold waters of temperate oceans. In East Asia, it is used to produce the sea vegetable products nori and gim ,...
3	Exposed	Occasional full Atlantic storm-waves	Infra-littoral: Laminaria dominant Mid-littoral: Balanus balanoides dominant on lower half; Chthalamus on upper with Patella aspera Patella aspera Patella aspera is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Patellidae, one of the families of true limpets.... ; Patella vulgata Patella vulgata Patella vulgata, colloquially known as the common limpet or Common European Limpet is an edible species of sea snail with gills, a typical true limpet, a marine gastropod mollusc in the family Patellidae. It is endemic to the waters off western Europe.-References:* Lespinet, Nederbragt, Cassan,...  abundant over whole Supra-littoral: top shells absent. Nucella Nucella Nucella, common name dog whelks or dog winkles, is a genus of small to medium-sized predatory sea snails, marine gastropod mollusks in the subfamily Ocenebrinae which is part of the large family Muricidae, the murex snails or rock snails....  on upper rock, Mytilus Mytilus Mytilus was an Illyrian king of the Dardanian Kingdom. Mytilus is probably the son of Monunius.Mytilus is the second Illyrian monarch to have struck in 270 BC coins bearing his name after Monunius...  in crevices
4	Semi-exposed	Obvious "reduction in wave action"	Infra-littoral: Laminaria abundant Mid-littoral: Chthalamus, Balanus Fucus serratus, Patella vulgata Patella vulgata Patella vulgata, colloquially known as the common limpet or Common European Limpet is an edible species of sea snail with gills, a typical true limpet, a marine gastropod mollusc in the family Patellidae. It is endemic to the waters off western Europe.-References:* Lespinet, Nederbragt, Cassan,...  common Supra-littoral: occasional Gibbula umbiliacus, Nucella Nucella Nucella, common name dog whelks or dog winkles, is a genus of small to medium-sized predatory sea snails, marine gastropod mollusks in the subfamily Ocenebrinae which is part of the large family Muricidae, the murex snails or rock snails....  on open rock

Modifications to the scale

A modified exposure scale of five stages applying to the shores of the British Isles is given by Lewis (1964):

1. Very Exposed Shores have a wide Verrucaria zone entirely above the upper tide level, a Porphyra
   Porphyra
   Porphyra is a foliose red algal genus of laver, comprising approximately 70 species. It grows in the intertidal zone, typically between the upper intertidal zone and the splash zone in cold waters of temperate oceans. In East Asia, it is used to produce the sea vegetable products nori and gim ,...
   
    zone above the barnacle level and Lichina pygmaea is locally abundant. The eulittoral zone is dominated by barnacles and limpets with a coralline belt in the very low littoral along with other Rhodophyta and Alaria
   Alaria
   Alaria is a genus of brown alga comprising approximately 17 species. Members of the genus are dried and eaten as a food in Western Europe, China, Korea, Japan , and South America 17:56, 1 August 2010...
   
    in the upper sublittoral.
2. Exposed Shores show a Verrucaria belt mainly above the high tide, with Porphyra
   Porphyra
   Porphyra is a foliose red algal genus of laver, comprising approximately 70 species. It grows in the intertidal zone, typically between the upper intertidal zone and the splash zone in cold waters of temperate oceans. In East Asia, it is used to produce the sea vegetable products nori and gim ,...
   
    and Lichina pygmaea. The mid shore is dominated by barnacles, limpets and some Fucus
   Fucus
   Fucus is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world.-Description and life cycle:...
   
   . Some Rhodophyta. Himanthalia and some Rhodophyta such as Mastocarpus and Corallina
   Corallina
   Corallina is a genus of red seaweeds with hard, abrasive calcareous skeletons in the family Corallinaceae. They are stiff, branched plants with articulations.-Species:*Corallina armata J.D.Hooker & Harvey, 1847...
   
    are found in the low littorral with Himanthalia, Alaria
   Alaria
   Alaria is a genus of brown alga comprising approximately 17 species. Members of the genus are dried and eaten as a food in Western Europe, China, Korea, Japan , and South America 17:56, 1 August 2010...
   
    and Laminaria
   Laminaria
   Laminaria is a genus of 31 species of brown algae , all sharing the common name "kelp". This economically important genus is characterized by long, leathery laminae and relatively large size. Some species are referred to by the common name Devil's apron, due to their shape, or sea colander, due to...
   
    digitata dominant in the upper sublittoral.
3. Semi-exposed Shores show a Verrucaria belt just above high tide with clear Pelvetia in the upper-littoral and Fucus serratus in the lower-littoral. Limpet
   Limpet
   Limpet is a common name for a number of different kinds of saltwater and freshwater snails ; it is applied to those snails that have a simple shell which is more or less conical in shape, and either is not spirally coiled, or appears not to be coiled in the adult snails.The name limpet is most...
   
   s, barnacles and short Fucus vesiculosus midshore. Fucus serratus with Rhodophyta, (Laurencia, Mastocarpus stellatus
   Mastocarpus stellatus
   Mastocarpus stellatus, also called Clúimhín Cait , carragheen, or false Irish moss, is a species of red algae closely related to Irish Moss, or Chondrus crispus. It is collected in Ireland and Scotland, together with Chondrus crispus as Irish Moss, dried, and sold for cooking and as the basis for a...
   
   , Rhodymenia
   Rhodymenia
   Rhodymenia is a genus of red algae, containing the following species:*Rhodymenia acanthophora Greville*Rhodymenia adnata Okamura*Rhodymenia arborescens E. Y. Dawson*Rhodymenia ardissonei Feldmann...
   
    and Lomentaria). Laminaria
   Laminaria
   Laminaria is a genus of 31 species of brown algae , all sharing the common name "kelp". This economically important genus is characterized by long, leathery laminae and relatively large size. Some species are referred to by the common name Devil's apron, due to their shape, or sea colander, due to...
   
     and Saccorhiza polyschides
   Saccorhiza polyschides
   Saccorhiza polyschides, common name Furbellow, is a large brown algae of the lower shore and is the largest seaweed found in Europe.-Description:...
   
    and small algae common in the sublittoral.
4. Sheltered Shores show a narrow Verrucaria zone at high water and a full sequence of fucoids: Pelvetia, Fucus spiralis
   Fucus spiralis
   Fucus spiralis is a species of seaweed, a brown alga , living on the littoral shore of the Atlantic coasts of Europe and North America. It has the common names of spiral wrack and flat wrack.-Description:...
   
   , Fucus vesiculosus, Fucus serratus, Ascophyllum nodosum
   Ascophyllum nodosum
   Ascophyllum nodosum is a large, common brown alga in the family Fucaceae, being the only species in the genus Ascophyllum. It is seaweed of the northern Atlantic Ocean, also known as rockweed, Norwegian kelp, knotted kelp, knotted wrack or egg wrack...
   
   . Laminaria digitata
   Laminaria digitata
   Laminaria digitata is a large brown alga in the family Laminariaceae, also known by the common name Oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean.-Description:...
   
    is dominant the upper sublittoral.
5. Very Sheltered Shores show a very narrow zone of Verrucaria, the dominance of the littoral by a full sequence of the fucoids and Ascophyllum covering the rocks. Laminaria saccharina
   Laminaria saccharina
   Saccharina latissima is a brown algae , of the family Laminariaceae. It is also known by the common name sea belt. It is found in the north east Atlantic Ocean and the Barents Sea south to Galicia in Spain. It is not found in the Bay of Biscay but is common round the coasts of the British...
   
   , Halidrys, Chondrus
   Chondrus
   Chondrus is a genus of red alga whose most famous species is C. crispus....
   
    and or Furcellaria.