information on the biology of species and the ecology of habitats found around the coasts and seas of the British Isles

Ephemeral green and red seaweeds on variable salinity and/or disturbed eulittoral mixed substrata



UK and Ireland classification

UK and Ireland classification


Eulittoral mixed substrata (pebbles and cobbles overlying sand or mud) that are subject to variations in salinity and/or siltation, characterized by dense blankets of ephemeral green and red seaweeds. The main species present are Ulva intestinalis, Ulva lactuca and Porphyra spp., along with colonial diatoms covering the surface of the substratum. Small numbers of other species such as barnacles Semibalanus balanoides and Elminius modestus are confined to any larger cobbles and pebbles or on the shells of larger individuals of the mussel Mytilus edulis. The crab Carcinus maenas and the winkle Littorina littorea can be present among the boulders, cobbles and seaweeds, while gammarids can be found in patches underneath the cobbles. In common with the other biotopes found on mixed substrata, patches of sediment are typically characterized by infaunal species including bivalves, for example, Cerastoderma edule and the polychaete Arenicola marina and the polychaete Lanice conchilega (JNCC, 2015).

Depth range

Mid shore

Additional information


Listed By

Further information sources

Search on:

Sensitivity reviewHow is sensitivity assessed?



Species indicative of sensitivity


Physical Pressures

No sensitivity data available

Chemical Pressures

No sensitivity data available

Biological Pressures

No sensitivity data available

Additional information



  1. Abou-Aisha, K.M., Kobbia, I., El Abyad, M., Shabana, E.F. & Schanz, F., 1995. Impact of phosphorus loadings on macro-algal communities in the Red Sea coast of Egypt. Water, Air, and Soil Pollution, 83 (3-4), 285-297.

  2. Airoldi, L., 2003. The effects of sedimentation on rocky coast assemblages. Oceanography and Marine Biology: An Annual Review, 41,161-236

  3. Airoldi, L. & Hawkins, S.J., 2007. Negative effects of sediment deposition on grazing activity and survival of the limpet Patella vulgataMarine Ecology Progress Series, 332, 235-240.

  4. Albrecht, A.S., 1998. Soft bottom versus hard rock: Community ecology of macroalgae on intertidal mussel beds in the Wadden Sea. Journal of Experimental Marine Biology and Ecology229 (1), 85-109.

  5. Alströem-Rapaport, C., Leskinen, E. & Pamilo, P., 2010. Seasonal variation in the mode of reproduction of Ulva intestinalis in a brackish water environment. Aquatic Botany, 93 (4), 244-249.

  6. Amsler, C.D. & Searles, R.B., 1980. Vertical distribution of seaweed spores in a water column off shore of North Carolina. Journal of Phycology, 16, 617-619.

  7. Arnold, D.C., 1957. The response of the limpet, Patella vulgata L., to waters of different salinities. Journal of the Marine Biological Association of the United Kingdom, 36, 121-128.

  8. Baeck, S., Lehvo, A. & Blomster, J., 2000. Mass occurrence of unattached Enteromorpha intestinalis on the Finnish Baltic Sea coast. Annales Botanici Fennici, 37, 155-161.

  9. Barnes, H. & Stone, R., 1972. Suppression of penis development in Balanus balanoides (L.). Journal of Experimental Marine Biology and Ecology, 9 (3), 303-309.

  10. Barnes, H., 1957. Processes of restoration and synchronization in marine ecology. The spring diatom increase and the 'spawning' of the common barnacle Balanus balanoides (L.). Année Biologique. Paris, 33, 68-85.

  11. Barnes, H., 1963. Light, temperature and the breeding of Balanus balanoides. Journal of the Marine Biological Association of the United Kingdom, 43 (03), 717-727.

  12. Barnes, H., Finlayson, D.M. & Piatigorsky, J., 1963. The effect of desiccation and anaerobic conditions on the behaviour, survival and general metabolism of three common cirripedes. Journal of Animal Ecology, 32, 233-252.

  13. Boney, A.D., 1969. A biology of marine algae. London: Hutchinson International.

  14. Bowman, R.S., 1985. The biology of the limpet Patella vulgata L. in the British Isles: spawning time as a factor determining recruitment sucess. In The Ecology of Rocky Coasts: essays presented to J.R. Lewis, D.Sc., (ed. P.G. Moore & R. Seed), Hodder and Stoughton, London, pages 178-193.

  15. Bowman, R.S. and Lewis, J.R., 1986. Geographical variation in the breeding cycles and recruitment of Patella spp. Hydrobiologia, 142, 41-56.

  16. Bowman, R.S. & Lewis, J.R., 1977. Annual fluctuations in the recruitment of Patella vulgata L. Journal of the Marine Biological Association of the United Kingdom, 57, 793-815.

  17. Brosnan, D.M. & Crumrine, L.L., 1994. Effects of human trampling on marine rocky shore communities. Journal of Experimental Marine Biology and Ecology, 177, 79-97.

  18. Cabral-Oliveira, J., Mendes, S., Maranhão, P. & Pardal, M., 2014. Effects of sewage pollution on the structure of rocky shore macroinvertebrate assemblages. Hydrobiologia, 726 (1), 271-283.

  19. Carlson, R.L., Shulman, M.J. & Ellis, J.C., 2006. Factors Contributing to Spatial Heterogeneity in the Abundance of the Common Periwinkle Littorina Littorea (L.). Journal of Molluscan Studies, 72 (2), 149-156.

  20. Clark, R.B., 1992. Marine pollution, 3rd edition. Oxford: Clarendon Press.

  21. Clark, R.B., 1997. Marine Pollution, 4th ed. Oxford: Carendon Press.

  22. Cole, K. & Conway, E., 1980. Studies in the Bangiaceae: reproductive modes. Botanica Marina, 23, 545-553.

  23. Connor, D.W., Allen, J.H., Golding, N., Howell, K.L., Lieberknecht, L.M., Northen, K.O. & Reker, J.B., 2004. The Marine Habitat Classification for Britain and Ireland. Version 04.05. Joint Nature Conservation Committee, Peterborough.

  24. Connor, D.W., Brazier, D.P., Hill, T.O., & Northen, K.O., 1997b. Marine biotope classification for Britain and Ireland. Vol. 1. Littoral biotopes. Joint Nature Conservation Committee, Peterborough, JNCC Report no. 229, Version 97.06., Joint Nature Conservation Committee, Peterborough, JNCC Report No. 230, Version 97.06.

  25. Corradi, M.G., Gorbi, G. & Zanni, C., 2006. Hypoxia and sulphide influence gamete production in Ulva sp. Aquatic Botany, 84 (2), 144-150.

  26. Crisp, D. & Patel, B., 1969. Environmental control of the breeding of three boreo-arctic cirripedes. Marine Biology, 2 (3), 283-295.

  27. Daly, M.A. & Mathieson, A.C., 1977. The effects of sand movement on intertidal seaweeds and selected invertebrates at Bound Rock, New Hampshire, USA. Marine Biology, 43, 45-55.

  28. Davenport, J. & Davenport, J.L., 2005. Effects of shore height, wave exposure and geographical distance on thermal niche width of intertidal fauna. Marine Ecology Progress Series, 292, 41-50.

  29. Davenport, J., Berggren, M.S., Brattegard, T., Brattenborg, N., Burrows, M., Jenkins, S., McGrath, D., MacNamara, R., Sneli, J.-A. & Walker, G., 2005. Doses of darkness control latitudinal differences in breeding date in the barnacle Semibalanus balanoides. Journal of the Marine Biological Association of the United Kingdom, 85 (01), 59-63.

  30. Davies, C.E. & Moss, D., 1998. European Union Nature Information System (EUNIS) Habitat Classification. Report to European Topic Centre on Nature Conservation from the Institute of Terrestrial Ecology, Monks Wood, Cambridgeshire. [Final draft with further revisions to marine habitats.], Brussels: European Environment Agency.

  31. Davies, S.P., 1970. Physiological ecology of Patella IV. Environmental and limpet body temperatures. Journal of the Marine Biological Association of the United Kingdom, 50 (04), 1069-1077.

  32. Ekaratne, S.U.K. & Crisp, D.J., 1984. Seasonal growth studies of intertidal gastropods from shell micro-growth band measurements, including a comparison with alternative methods. Journal of the Marine Biological Association of the United Kingdom, 64, 183-210.

  33. Evans, R.G., 1948. The lethal temperatures of some common British littoral molluscs. The Journal of Animal Ecology, 17, 165-173.

  34. Flindt, M.R., Pedersen, C.B., Amos, C.L., Levy, A., Bergamasco, A. & Friend, P., 2007. Transport, sloughing and settling rates of estuarine macrophytes: Mechanisms and ecological implications. Continental Shelf Research, 27 (8), 1096-1103.

  35. Foster, B.A., 1970. Responses and acclimation to salinity in the adults of some balanomorph barnacles. Philosophical Transactions of the Royal Society of London, Series B, 256, 377-400.

  36. Foster, B.A., 1971b. On the determinants of the upper limit of intertidal distribution of barnacles. Journal of Animal Ecology, 40, 33-48.

  37. Fretter, V. & Graham, A., 1994. British prosobranch molluscs: their functional anatomy and ecology, revised and updated edition. London: The Ray Society.

  38. Grenon, J.F. & Walker, G., 1981. The tenacity of the limpet, Patella vulgata L.: an experimental approach. Journal of Experimental Marine Biology and Ecology, 54, 277-308.

  39. Hawes, I. & Smith, R., 1995. Effect of current velocity on the detachment of thalli of Ulva lactuca (Chlorophyta) in a New Zealand estuary. Journal of Phycology, 31 (6), 875-880.

  40. Hawkins, S. J. & Jones, H. D., 1992. Rocky Shores. London: Immel.

  41. Hayden, H.S., Blomster, J., Maggs, C.A., Silva, P.C., Stanhope, M.J. & Waaland, J.R., 2003. Linnaeus was right all along: Ulva and Enteromorpha are not distinct genera. European Journal of Phycology, 38, 277-294.

  42. Hetherington, J.A., 1976. Radioactivity in surface and coastal waters of the British Isles. Fisheries Radiobiological Laboratory Technical Report, 11, 1-35.

  43. Hill, S., Burrows, S.J. & Hawkins, S.J., 1998. Intertidal Reef Biotopes (Volume VI). An overview of dynamics and sensitivity characteristics for conservation management of marine Special Areas of Conservation. Oban: Scottish Association for Marine Science (UK Marine SACs Project)., Scottish Association for Marine Science (UK Marine SACs Project).

  44. Houghton, D.R., Pearman, I. & Tierney, D., 1973. The effect of water velocity on the settlement of swarmers of the green alga Enteromorpha. In Proceedings of the third international congress on marine corrosion and fouling (ed. R.F. Acker, B. Floyd Brown, J.R. DePalma & W.P. Iverson), 682-690. Evanston, Northwestern University Press.

  45. Hruby, T. & Norton, T.A., 1979. Algal colonization on rocky shores in the Firth of Clyde. Journal of Ecology, 67, 65-77.

  46. Hyslop B.T. & Davies, M.S., 1998. Evidence for abrasion and enhanced growth of Ulva lactuca L. in the presence of colliery waste particles. Environmental Pollution, 101 (1), 117-121.

  47. Hyslop, B.T., Davies, M.S., Arthur, W., Gazey, N.J. & Holroyd, S., 1997. Effects of colliery waste on littoral communities in north-east England. Environmental Pollution, 96 (3), 383-400.

  48. Jenkins, S., Åberg, P., Cervin, G., Coleman, R., Delany, J., Della Santina, P., Hawkins, S., LaCroix, E., Myers, A. & Lindegarth, M., 2000. Spatial and temporal variation in settlement and recruitment of the intertidal barnacle Semibalanus balanoides (L.)(Crustacea: Cirripedia) over a European scale. Journal of Experimental Marine Biology and Ecology, 243 (2), 209-225.

  49. Jenkins, S., Coleman, R., Della Santina, P., Hawkins, S., Burrows, M. & Hartnoll, R., 2005. Regional scale differences in the determinism of grazing effects in the rocky intertidal. Marine Ecology Progress Series, 287, 77-86.

  50. Jenkins, S.R., Beukers-Stewart, B.D. & Brand, A.R., 2001. Impact of scallop dredging on benthic megafauna: a comparison of damage levels in captured and non-captured organisms. Marine Ecology Progress Series, 215, 297-301.

  51. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line]

  52. Kain, J.M., & Norton, T.A., 1990. Marine Ecology. In Biology of the Red Algae, (ed. K.M. Cole & Sheath, R.G.). Cambridge: Cambridge University Press.

  53. Kamer, K. & Fong, P., 2001. Nitrogen enrichment ameliorates the negative effects of reduced salinity on green macroalga Enteromorpha intestinalis. Marine Ecology Progress Series, 218, 87-93.

  54. Kamermans, P., Malta, E.-j., Verschuure, J.M., Lentz, L.F. & Schrijvers, L., 1998. Role of cold resistance and burial for winter survival and spring initiation of an Ulva spp.(Chlorophyta) bloom in a eutrophic lagoon (Veerse Meer lagoon, The Netherlands). Marine Biology, 131 (1), 45-51.

  55. Kennison, R.L. & Fong, P., 2013. High amplitude tides that result in floating mats decouple algal distribution from patterns of recruitment and nutrient sources. Marine Ecology Progress Series, 494, 73-86.

  56. Kinne, O. (ed.), 1972. Marine Ecology: A Comprehensive, Integrated Treatise on Life in Oceans and Coastal Waters,Vol.1, Environmental Factors, part 3. New York: John Wiley & Sons.

  57. Kitching, J.A. & Thain, V.M., 1983. The ecological impact of the sea urchin Paracentrotus lividus (Lamarck) in Lough Ine, Ireland. Philosophical Transactions of the Royal Society of London, Series B, 300, 513-552.

  58. Kraufvelin, P., 2007. Responses to nutrient enrichment, wave action and disturbance in rocky shore communities. Aquatic Botany, 87 (4), 262-274.

  59. Kylin, H., 1917. Kalteresistenze der Meerealen. Bericht der Deutschen Botanischen Gesellschafter, 35, 370-384.

  60. Leal, M.L.F., Vascencelos, M.T., Sousa-Pinto, I. & Cabral, J.P.S., 1997. Biomonitoring with benthic macroalgae and direct assay of heavy metals in seawater of the Oporto coast (northwest Portugal) Marine Pollution Bulletin, 34, 1006-1015.

  61. Lein, T.E., 1980. The effects of Littorina littorea L.(Gastropoda) grazing on littoral green algae in the inner Oslofjord, Norway. Sarsia, 65 (2), 87-92.

  62. Le Quesne W.J.F. 2005. The response of a protandrous species to exploitation, and the implications for management: a case study with patellid limpets. PhD thesis. University of Southampton, Southampton, United Kingdom.

  63. Lersten, N.R. & Voth, P.D., 1960. Experimental control of zoid discharge and rhizoid formation in the green alga Enteromorpha. Botanical Gazette, 122, 33-45.

  64. Lewis, S., May, S., Donkin, M.E. & Depledge, M.H., 1998. The influence of copper and heat shock on the physiology and cellular stress response of Enteromorpha intestinalis. Marine Environmental Research, 46, 421-424.

  65. Littler, M.M., Martz, D.R. & Littler, D.S., 1983. Effects of recurrent sand deposition on rocky intertidal organisms: importance of substrate heterogeneity in a fluctuating environment. Marine Ecology Progress Series. 11 (2), 129-139.

  66. Lobban, C.S. & Harrison, P.J., 1997. Seaweed ecology and physiology. Cambridge: Cambridge University Press.

  67. Long, J.D., Cochrane, E. & Dolecal, R., 2011. Previous disturbance enhances the negative effects of trampling on barnacles. Marine Ecology Progress Series, 437, 165-173.

  68. Luther, G., 1976. Bewuchsuntersuchungen auf Natursteinsubstraten im Gezeitenbereich des Nordsylter Wattenmeeres: Algen. Helgoländer Wissenschaftliche Meeresuntersuchungen, 28 (3-4), 318-351.

  69. Markager, S., 1993. Light absorption and quantum yield for growth in five species of marine macroalgae. Journal of Phycology, 29 (1), 54-63.

  70. Marshall, D.J. & McQuaid, C.D., 1989. The influence of respiratory responses on the tolerance to sand inundation of the limpets Patella granularis L.(Prosobranchia) and Siphonaria capensis Q. et G.(Pulmonata). Journal of Experimental Marine Biology and Ecology, 128 (3), 191-201.

  71. Martinez, B., Pato, L.S. & Rico, J.M., 2012. Nutrient uptake and growth responses of three intertidal macroalgae with perennial, opportunistic and summer-annual strategies. Aquatic Botany, 96 (1), 14-22.

  72. Martins, I., Oliveira, J.M., Flindt, M.R. & Marques, J.C., 1999. The effect of salinity on the growth rate of the macroalgae Enteromorpha intestinalis (Chlorophyta) in the Mondego estuary (west Portugal). Acta Oecologica, 20 (4), 259-265.

  73. McAllen, R., 1999. Enteromorpha intestinalis - a refuge for the supralittoral rockpool harpacticoid copepod Tigriopus brevicornis. Journal of the Marine Biological Association of the United Kingdom, 79, 1125-1126.

  74. Mieszkowska, N., Burrows, M.T., Pannacciulli, F.G. & Hawkins, S.J., 2014. Multidecadal signals within co-occurring intertidal barnacles Semibalanus balanoides and Chthamalus spp. linked to the Atlantic Multidecadal Oscillation. Journal of Marine Systems, 133, 70-76.

  75. Moss, B.L. & Woodhead, P., 1975. The effect of two commercial herbicides on the settlement, germination and growth of Enteromorpha. Marine Pollution Bulletin, 6, 189-192.

  76. Munda, I.M., 1984. Salinity dependent accumulation of Zn, Co and Mn in Scytosiphon lomentaria (Lyngb.) Link and Enteromorpha intestinalis (L.) from the Adriatic Sea. Botanica Marina, 27, 371-376.

  77. Newell, R.C., 1979. Biology of intertidal animals. Faversham: Marine Ecological Surveys Ltd.

  78. Niesenbaum R.A., 1988. The ecology of sporulation by the macroalga Ulva lactuca L. (chlorophyceae). Aquatic Botany, 32, 155-166.

  79. Pedersen, M.F., Borum, J. & Fotel, L. F., 2009. Phosphorus dynamics and limitation of fast and slow-growing temperate seaweeds in Oslofjord, Norway. Marine Ecology Progress Series, 399, 103-115

  80. Povey, A. & Keough, M.J., 1991. Effects of trampling on plant and animal populations on rocky shores. Oikos61: 355-368.

  81. Rai, L., Gaur, J.P. & Kumar, H.D., 1981. Phycology and heavy-metal pollution. Biological Reviews, 56, 99-151.

  82. Reed, R. H., Collins, J.C. & Russell, G., 1980. The influence of variations in salinity upon photosynthesis in the marine alga Porphyra purpurea (Roth) C. Ag. (Rhodophyta, Bangiales). Z. Pflanzenphysiology, 98, 183-187.

  83. Reed, R.H. & Russell, G., 1979. Adaptation to salinity stress in populations of Enteromorpha intestinalis (L.) Link. Estuarine and Coastal Marine Science, 8, 251-258.

  84. Ribeiro, P.A., Xavier, R., Santos, A.M. & Hawkins, S.J., 2009. Reproductive cycles of four species of Patella (Mollusca: Gastropoda) on the northern and central Portuguese coast. Journal of the Marine Biological Association of the United Kingdom, 89 (06), 1215-1221.

  85. Rice, H., Leighty, D.A. & McLeod, G.C., 1973. The effects of some trace metals on marine phytoplankton. CRC Critical Review in Microbiology, 3, 27-49.

  86. Robles, C., 1982. Disturbance and predation in an assemblage of herbivorous Diptera and algae on rocky shores. Oecologia, 54 (1), 23-31.

  87. Rognstad, R.L., Wethey, D.S. & Hilbish, T.J., 2014. Connectivity and population repatriation: limitations of climate and input into the larval pool. Marine Ecology Progress Series, 495, 175-183.

  88. Say, P.J., Burrows, I.G. & Whitton, B.A., 1990. Enteromorpha as a monitor of heavy metals in estuaries. Hydrobiologia, 195, 119-126.

  89. Scarlett, A., Donkin, M.E., Fileman, T.W. & Donkin, P., 1997. Occurrence of the marine antifouling agent Irgarol 1051 within the Plymouth Sound locality: implications for the green macroalga Enteromorpha intestinalis. Marine Pollution Bulletin, 38, 645-651.

  90. Shanks, A.L. & Wright, W.G., 1986. Adding teeth to wave action- the destructive effects of wave-bourne rocks on intertidal organisms. Oecologia, 69 (3), 420-428.

  91. Shepherd, S.A., Watson, J.E., Womersley, H.B.S. & Carey, J.M., 2009. Long-term changes in macroalgal assemblages after increased sedimentation and turbidity in Western Port, Victoria, Australia. Botanica Marina, 52 (3), 195-206.

  92. Smith, G.M., 1947. On the reproduction of some Pacific coast species of Ulva. American Journal of Botany, 34, 80-87.

  93. Smith, J.E. (ed.), 1968. 'Torrey Canyon'. Pollution and marine life. Cambridge: Cambridge University Press.

  94. Southward, A.J., Hawkins, S.J. & Burrows, M.T., 1995. Seventy years observations of changes in distribution and abundance of zooplankton and intertidal organisms in the western English Channel in relation to rising sea temperature. Journal of Thermal Biology, 20, 127-155.

  95. Sverdrup, H.U., Johnson, M.W. & Fleming, R.H., 1942. The Oceans. New York: Prentice Hall.

  96. Tighe-Ford, D., 1967. Possible mechanism for the endocrine control of breeding in a cirripede. Nature, 216, 920-921.

  97. Tolhurst, L.E., Barry, J., Dyer, R.A. & Thomas, K.V., 2007. The effect of resuspending sediment contaminated with antifouling paint particles containing Irgarol 1051 on the marine macrophyte Ulva intestinalis. Chemosphere, 68 (8), 1519-1524.

  98. Tyler-Walters, H. & Arnold, C., 2008. Sensitivity of Intertidal Benthic Habitats to Impacts Caused by Access to Fishing Grounds. Report to Cyngor Cefn Gwlad Cymru / Countryside Council for Wales from the Marine Life Information Network (MarLIN) [Contract no. FC 73-03-327], Marine Biological Association of the UK, Plymouth, pp.

  99. UKTAG, 2014. UK Technical Advisory Group on the Water Framework Directive [online]. Available from:

  100. Vadas, R.L., Johnson, S. & Norton, T.A., 1992. Recruitment and mortality of early post-settlement stages of benthic algae. British Phycological Journal, 27, 331-351.

  101. Vadas, R.L., Keser, M. & Rusanowski, P.C., 1976. Influence of thermal loading on the ecology of intertidal algae. In Thermal Ecology II, (eds. G.W. Esch & R.W. McFarlane), ERDA Symposium Series (Conf-750425, NTIS), Augusta, GA, pp. 202-212.

  102. Vaudrey, J.M.P., Kremer, J.N., Branco, B.F. & Short, F.T., 2010. Eelgrass recovery after nutrient enrichment reversal. Aquatic Botany, 93 (4), 237-243.

  103. Vermaat J.E. & Sand-Jensen, K., 1987. Survival, metabolism and growth of Ulva lactuca under winter conditions: a laboratory study of bottlenecks in the life cycle. Marine Biology, 95 (1), 55-61.

  104. Wells, E., Best, M., Scanlan, C. & Foden, J., 2014. Opportunistic Macroalgae Blooming. Water Framework Directive- development of classification tools for ecological assessment., Water Framework Directive-United Kingdom Technical Advisory Group (WFD-UKTAG),


This review can be cited as:

Tillin, H.M. & Budd, G., 2016. Ephemeral green and red seaweeds on variable salinity and/or disturbed eulittoral mixed substrata. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 19-06-2018]. Available from:

Last Updated: 30/03/2016