Skip to main content Accessibility help
  • Print publication year: 2012
  • Online publication date: December 2012

Chapter Twelve - Processes influencing bird use of estuarine mudflats and saltmarshes in western Europe


The intertidal zone between land and sea provides some of the most productive and complex of habitats, supporting vast numbers of birds of many species. This chapter explores patterns of use of estuarine mudflats and saltmarshes by birds, drivers of within- and between-estuary variation in use of estuarine resources by these species, and consequences of recent environmental changes on estuaries. A series of case studies of anthropogenic impacts on estuarine habitats and their implications for bird populations is described. Although the primary geographic focus of these examples is western Europe, and particularly Britain, estuaries across the globe are experiencing similar threats and impacts. There are also large intertidal areas outside estuaries that provide rather different environments for birds; these are discussed in Chapter 13.

The estuarine environment and its bird assemblages

Estuarine mudflats and sandflats typically occur in areas of shallow, sheltered tidal water, where currents from rivers and tidal movements slow sufficiently to allow settlement of particles of sediment. Sand and gravel particles are typically large enough to settle out of the water column directly, but the settlement of finer particles of silt and clay is aided by the surface attraction displayed by these fine sediments when in salt water, in a process known as flocculation. The resulting formation of extensive areas of mud and sandflat creates a habitat of extreme importance for many intertidal species and communities (Fig. 12.1).

Allen, J. R. L. 2000 Morphodynamics of Holocene saltmarshes: A review sketch from the Atlantic and Southern North Sea coasts of EuropeQuaternary Sci. Rev. 19 1155
Alves, J. A.Sutherland, W. J.Gill, J. A. 2012 Will improving wastewater treatment impact shorebirds? Effects of sewage discharges on estuarine invertebrates and birdsAnim. Conserv. 15 44
Atkinson, P. W.Clark, N. A.Bell, M. C. 2003 Changes in commercially fished shellfish stocks and shorebird populations in the Wash, EnglandBiol. Conserv. 114 127
Atkinson, P. W.Crooks, S.Drewitt, A. 2004 Managed realignment in the UK – the first 5 years of colonization by birdsIbis 146 101
Atkinson, P. W.Crooks, S.Grant, A.Rehfisch, M. M. 2001 The Success of Creation and Restoration Schemes in Producing Intertidal Habitat Suitable for WaterbirdsEnglish Nature Research Reports. PeterboroughEnglish Nature
Atkinson, P. W.Maclean, I. M. D.Clark, N. A. 2010 Impacts of shellfisheries on waterbird community composition in the Wash, EnglandJ. Appl. Ecol. 47 191
Badley, J.Allcorn, R. I. 2006 The creation of a new saline lagoon as part of a flood defence scheme at Freiston Shore RSPB Reserve, Lincolnshire, EnglandConserv. Evidence 3 99
Bathe, G. 2007 Political and social drivers for access to the countryside: the need for research on birds and recreational disturbanceIbis 149 3
Beukema, J. J. 1991 Changes in composition of bottom fauna of a tidal-flat area during a period of eutrophicationMar. Biol. 111 293
Beukema, J. J. 1992 Expected changes in the Wadden Sea benthos in a warmer world: lessons from periods with mild wintersNeth. J. Sea Res. 30 73
Bregnballe, T.Madsen, J.Rasmussen, P. 2004 Effects of temporal and spatial hunting control in waterbird reservesBiol. Conserv. 119 93
Brindley, E.Norris, K.Cook, T. 1998 The abundance and conservation status of redshank nesting on saltmarshes in Great BritainBiol. Conserv. 86 289
Brown, A. F.Atkinson, P. W. 1996 Habitat associations of coastal wintering passerinesBird Study 43 188
Burd, F. 1989 The Saltmarsh Survey of Great BritainPeterboroughNature Conservancy Council
Burton, P. J. K. 1974 Feeding and the Feeding Apparatus in WadersLondonBritish Museum (Natural History
Burton, N. H. KArmitage, M. J. S. 2005 Differences in the diurnal and nocturnal use of intertidal feeding grounds by Redshank Bird Study 52 120
Burton, N. H. K.Armitage, M. J. S. 2008 Settlement of Redshank following winter habitat loss: effects of prior knowledge and ageArdea 96 191
Burton, N. H. K.Dodd, S. G.Clark, N. A.Ferns, P. N. 2002 Breeding origins of Redshank wintering at two neighbouring sites on the Severn Estuary: evidence for partial racial segregationRing. Migr. 21 19
Burton, N. H. KFuller, R. A.Eaton, M. A. 2005 Between-year changes in the wintering sites of Ruddy Turnstones : a response to diminished food resources?Wader Study Group Bull. 107 36
Burton, N. H. K.Musgrove, A. J.Rehfisch, M. M.Sutcliffe, A.Waters, R. 2003 Numbers of wintering gulls in the United Kingdom, Channel Islands and Isle of Man: a review of the 1993 and previous Winter Gull Roost SurveysBrit. Birds 96 376
Burton, N. H. KRehfisch, M. M.Clark, N. A.Dodd, S. G. 2006 Impacts of sudden winter habitat loss on the body condition and survival of redshank J. Appl. Ecol. 43 464
Campbell, L. H. 1984 The impact of changes in sewage treatment on seaducks wintering in the Firth of Forth, ScotlandBiol. Conserv. 28 173
Cardell, M. J.Sardà, R.Romero, J. 1999 Spatial changes in sublittoral soft-bottom polychaete assemblages due to river inputs and sewage dischargesActa Oecol. 20 343
Clark, J. A. 2009 Selective mortality of waders during severe weatherBird Study 56 96
Cramp, S.Simmons, K. E. L. 1977 The Birds of the Western Palearctic Volume IOxfordOxford University Press
Davidson, N. C. D.d’A Laffoley, D.Doody, J. P. 1991 Nature Conservation and Estuaries in Great BritainPeterboroughNature Conservancy Council
Davy, A. J.Bakker, J. P.Figueroa, M. E. 2009 Human Modification of European SaltmarshesHuman Impacts on Salt Marshes: A Global PerspectiveSilliman, B. R.Grosholz, E. D.Bertness, M. D.311Berkeley, CaliforniaUniversity of California Press
Delany, S.Scott, D.Dodman, T.Stroud, D. 2009 An Atlas of Wader Populations in Africa and Western EurasiaWageningenWetlands International
Derrett, K.Smith, R. 2001 The status of Icelandic Redshank in north Kent during autumnRing. Migr. 20 338
Dias, M. P.Granadeiro, J. P.Lecoq, M.Santos, C. D.Palmeirim, J. M. 2006 Distance to high-tide roosts constrains the use of foraging areas by dunlins: implications for the management of estuarine wetlandsBiol. Conserv. 131 446
Dierschke, J.Barlein, F. 2004 Habitat selection of wintering passerines in saltmarshes of the German Wadden SeaJ. Ornithol. 145 48
Doody, J. P. 1992 The conservation of British saltmarshesSaltmarshes: Morphodynamics, Conservation and Engineering SignificanceAllen, J. R. L.Pye, K.80CambridgeCambridge University Press
Ebbinge, B. S.Spaans, B. 1995 The importance of body reserves accumulated in spring staging areas in the temperate zone for breeding in dark-bellied brent geese in the high ArcticJ. Avian Biol. 26 105
Esselink, P.Zwarts, L. 1989 Seasonal trend in burrow depth and tidal variation in feeding activity of Mar. Ecol. Prog. Ser. 56 243
Ferns, P. N.Rostron, D. M.Siman, H. Y. 2000 Effects of mechanical cockle harvesting on intertidal communitiesJ. Appl. Ecol. 37 464
Fuller, R. J. 1982 Bird Habitats in BritainCaltonPoyser
Gill, J. A. 2007 Approaches to measuring the effects of human disturbance on birdsIbis 149 9
Gill, J. A.Langston, R. H. W.Alves, J. A. 2008 Contrasting trends in two Black-tailed Godwit populations: a review of causes and recommendationsWader Study Group Bull. 114 43
Gill, J. A.Norris, K.Potts, P. M. 2001 The buffer effect and large-scale population regulation in migratory birdsNature 412 436
Gill, J. A.Norris, K.Sutherland, W. J. 2001 The effects of disturbance on habitat use by black-tailed godwits, J. Appl. Ecol. 38 846
Gill, J. A.Sutherland, W. J.Norris, K. 2001 Depletion models can predict shorebird distribution at different spatial scalesProc. R. Soc. B 268 369
Gillings, S.Fuller, R. J. 2001 Habitat selection by skylarks wintering in Britain in 1997/98Bird Study 28 293
Goss-Custard, J. D. 1996 The Oystercatcher: From Individuals to PopulationsOxfordOxford University Press
Goss-Custard, J. D.Burton, N. H. K.Clark, N. A. 2006 Test of a behavior-based individual-based model: response of shorebird mortality to habitat lossEcol. Appl. 16 2215
Goss-Custard, J. D.Stillman, R. A.West, A. D. 2003 When enough is not enough: shorebirds and shellfishingProc. R. Soc. B 271 233
Gunnarsson, T. G.Gill, J. ANewton, J.Potts, P. M.Sutherland, W. J. 2005 Seasonal matching of habitat quality and fitness in migratory birdsProc. R. Soc. B 272 2319
Hill, D.Rushton, S. P.Clark, N. A.Green, P.Prys-Jones, R. 1993 Shorebird communities on British estuaries: factors affecting community compositionJ. Appl. Ecol. 30 220
IPCC 2007 Climate change 2007: Synthesis ReportGenevaIPCC
Johnston, S. A. 1981 Estuarine dredge and fill activities: a review of impactsEnviron. Manage. 5 427
Kalejta-Summers, B. 1997 Diet and habitat preferences of wintering passerines on the Taff/Ely saltmarshesBird Study 44 367
Knott, N. A.Aulbury, J. P.Brown, T. H.Johnston, E. L. 2009 Contemporary ecological threats from historical pollution sources: impacts of large-scale resuspension of contaminated sediments on sessile invertebrate recruitmentJ. Appl. Ecol. 46 770
Kraan, C.Piersma, T.Dekinga, A.Koolhas, A.van der Meer, J. 2007 Dredging for edible cockles () on intertidal flats: short-term consequences of fisher patch-choice decisions for target and non-target benthic faunaICES J. Mar. Sci. 64 1735
Kraan, C.van Gils, J. A.Spaans, B. 2009 Landscape-scale experiment demonstrates that Wadden Sea intertidal flats are used to capacity by molluscivore migrant shorebirdsJ. Anim. Ecol. 78 1259
Lie, H. J.Cho, C. H.Lee, S. 2008 Changes in marine environment by a large coastal development of the Saemangeum Reclamation Project in KoreaOcean Polar Res. 30 373
Liley, D.Sutherland, W. J. 2007 Predicting the population consequences of human disturbance for Ringed Plovers : a game theory approachIbis 149 82
Lotze, H. K.Lenihan, H. S.Bourque, B. J. 2006 Depletion, degradation, and recovery potential of estuaries and coastal seasScience 213 1806
Madsen, J. 1995 Impacts of disturbance on migratory waterfowlIbis 137 67
Madsen, J. 1998 Experimental refuges for migratory waterfowl in Danish wetlands. II. Tests of hunting disturbance effectsJ. Appl. Ecol. 35 398
Madsen, J.Cracknell, G.Fox, A. D. 1999 Goose Populations of the Western Palearctic: A Review of Status and DistributionWageningenWetlands International
Martin, G. R.Piersma, T. 2009 Vision and touch in relation to foraging and predator detection: insightful contrasts between a plover and a sandpiperProc. R. Soc. B 276 437
McLusky, D. S.Elliott, M. 2004 The Estuarine Ecosystem: Ecology, Threats and ManagementOxfordOxford University Press
Mendonca, V. M.Raffaelli, D. G.Boyle, P. R. 2007 Interactions between shorebirds and benthic invertebrates at Culbin Sands lagoon, NE Scotland: effects of avian predation on their prey community density and structureSci. Mar. 71 579
Möller, I.Spencer, T.French, J. R.Leggett, D. J.Dixon, M. 1999 Wave transformation over salt marshes: a field and numerical modelling study from North Norfolk, EnglandEstuar. Coast. Shelf Sci. 49 411
Musgrove, A. J.Langston, R. H. W.Baker, H.Ward, R. M. 2003 Estuarine Waterbirds at Low Tide: the WeBS Low Tide Counts 1992/93 to 1998/99ThetfordWSG/BTO/WWT/RSPB/JNCC
Newton, I. 2008 The Migration Ecology of BirdsLondonAcademic Press
Norris, K. 2004 Managing threatened species: the ecological toolbox, evolutionary theory and declining-population paradigmJ. Appl. Ecol. 41 413
Norris, K.Atkinson, P. W. 2000 Declining populations of coastal birds in Great Britain: victims of sea-level rise and climate change?Environ. Res. 8 303
Norris, K.Atkinson, P. W.Gill, J. A. 2004 Climate change and coastal waterbird populations – past declines and future impactsIbis 146 83
Norris, K.Brindley, E.Cook, T. 1998 Is the density of redshank nesting on saltmarshes in Great Britain declining due to changes in grazing managementJ. Appl. Ecol. 35 621
Norris, K.Buisson, R. 1994 Sea-level rise and its impact upon coastal birds in the UKRSPB Conserv. Rev. 8 63
Norris, K.Cook, T.O’Dowd, B.Durdin, C. 1997 The density of redshank breeding on the salt- marshes of the Wash in relation to habitat and its grazing managementJ. Appl. Ecol. 34 999
Percival, S. M.Sutherland, W. J.Evans, P. R. 1998 Intertidal habitat loss and wildfowl numbers: applications of a spatial depletion modelJ. Appl. Ecol. 35 57
Peters, K. A.Otis, D. L. 2007 Shorebird roost-site selection at two temporal scales: is human disturbance a factor?J. Appl. Ecol. 44 196
Philippart, C. J.van Akken, H. M.Beukema, J. J. 2003 Climate-related changes in recruitment of the bivalve Limnol.Oceanogr. 48 2171
Piersma, T.Koolhaas, A.Dekinga, A. 2001 Long-term indirect effects of mechanical cockle-dredging on intertidal bivalve stocks in the Wadden SeaJ. Appl. Ecol. 38 976
Piersma, T.van Aelst, R.Kurk, K.Berkhoudt, K.Maas, L. R. M. 1998 A new pressure sensory mechanism for prey detection in birds: the use of principles of seabed dynamics?Proc. R. Soc. B 265 1377
Pounder, B. 1976 Wintering flocks of Goldeneyes at sewage outfalls in the Tay estuaryBird Study 23 121
Prater, A. J. 1981 Estuary Birds of Britain and IrelandCaltonPoyser
Quinn, J. L.Cresswell, W. 2004 Predator hunting behaviour and prey vulnerabilityJ. Anim. Ecol. 73 143
Ratikainen, I. I.Gill, J. A.Gunnarsson, T. G.Sutherland, W. J.Kokko, H. 2008 When density-dependence is not instantaneous: theoretical developments and management implicationsEcol. Lett. 11 184
Raven, S. J.Coulson, J. C. 2001 Effects of cleaning a tidal river of sewage on gull numbers: a before-and-after study of the River Tyne, northeast EnglandBird Study 48 48
Ravenscroft, N. O. M.Beardall, C. H. 2003 The importance of freshwater flows over estuarine mudflats for wintering waders and wildfowlBiol. Conserv. 113 89
Rehfisch, M. M.Clark, N. A.Langston, R. H. W.Greenwood, J. J. D. G. 1996 A guide to the provision of refuges for waders: an analysis of 30 years of ringing data from the Wash, EnglandJ. Appl. Ecol. 33 673
Rehfisch, M. M.Insley, H.Swann, B. 2003 Fidelity of overwintering shorebirds to roosts on the Moray Basin, Scotland: implications for predicting impacts of habitat lossArdea 91 53
Reynolds, J. D.Székely, T. 1997 The evolution of parental care in shorebirds: life histories, ecology, and sexual selectionBehav. Ecol. 8 126
Rogers, D. I.Battley, P. F.Piersma, T.van Gils, J. A.Rogers, K. G. 2006 High-tide habitat choice: insights from modeling roost selection by shorebirds around a tropical bayAnim. Behav. 72 563
Rogers, D. I.Piersma, T.Hassell, C. J. 2006 Roost availability may constrain shorebird distribution: exploring the energetic costs of roosting and disturbance around a tropical bayBiol. Conserv. 133 225
Rosa, S.Encarnação, A. L.Granadeiro, J. P.Palmeirim, J. M. 2006 High-tide roost selection by waders: maximizing feeding opportunities or avoiding predation?Ibis 148 88
Savage, C.Elmgren, R.Larsson, U. 2002 Effect of sewage-derived nutrients on an estuarine macrobenthic communityMar. Ecol. Prog. Ser. 243 67
Sitters, H.González, P.Piersma, T.Baker, A. J.Price, D. J. 2001 Day and night feeding habitat of red knots in Patagonia: profitability versus safety?J. Field Ornithol. 72 86
Smart, J. 2005
Smart, J.Gill, J. A. 2003 Climate change and the potential impact on breeding waders in the UKWader Study Group Bull. 100 80
Smart, J.Gill, J. A. 2003 Non-intertidal habitat use by shorebirds: a reflection of inadequate intertidal resources?Biol. Conserv. 111 359
Smart, J.Gill, J. A.Sutherland, W. J.Watkinson, A. R. 2006 Predicting the habitat requirements of waders breeding on grasslandJ. Appl. Ecol. 43 454
Stillman, R. A.Goss-Custard, J. D.West, A. D. 2000 Predicting mortality in novel environments: tests and sensitivity of a behaviour-based modelJ. Appl. Ecol. 37 564
Stillman, R. A.Goss-Custard, J. D.West, A. D. 2001 Predicting shorebird mortality and population size under different regimes of shellfishery managementJ. Appl. Ecol. 38 857
Summers, R. W.Nicoll, M.Underhill, L. G.Petersen, A. 1988 Methods for estimating the proportions of Icelandic and British redshanks in mixed populations wintering on British coastsBird Study 35 169
Sutherland, W. J.Norris, K. 2002 Behavioural models of population growth rates: implications for conservation and predictionPhil. Trans. R. Soc. B 357 1273
Turner, R. K.Burgess, D.Hadley, D.Coombes, E.Jackson, N. 2007 A cost–benefit appraisal of coastal managed realignment policyGlobal Environ. Change 17 397
UKCIP 2005 Updates to Regional Net Sea-Level Change Estimates for Great BritainOxfordUKCIP
van de Kam, J.Ens, B. J.Piersma, T.Zwarts, L. 2004 Shorebirds: An illustrated Behavioural EcologyUtrechtKNNV Publishers
van Gils, J. A.Dekinga, A.Spaans, B.Vahl, W. TPiersma, T. 2005 Digestive bottleneck affects foraging decisions in red knots . II. Patch choice and length of working dayJ. Anim. Ecol. 74 120
van Gils, J. A.Spaans, B.Dekinga, A.Piersma, T. 2006 Foraging and a tidally structured environment by red knots (): ideal, but not freeEcology 87 1189
van Gils, J. A.Piersma, T.Dekinga, A.Spaans, B.Kraan, C. 2006 Shellfish dredging pushes a flexible avian top predator out of a Marine Protected AreaPLOS Biol. 4 2399
van Roomen, M.van Turnhout, C.van Winden, 2005 Trends in benthivorous waterbirds in the Dutch Wadden Sea 1975–2002: large differences between shellfisheaters and worm-eatersLimosa 78 21
Verhulst, S.Oosterbeek, K.Rutten, A. L.Ens, B. J. 2004 Shellfish fishery severely reduces condition and survival of oystercatchers despite creation of large marine protected areasEcol. Society 9 17
Vickery, J. A.Sutherland, W. J.Watkinson, A. R.Rowcliffe, J. M.Lane, S. J. 1995 Habitat switching by dark-bellied brent geese (L.) in relation to food depletionOecologia 103 499
Watkinson, A. R.Gill, J. A.Hulme, M. 2004 Flying in the face of climate change: a review of climate change, past, present and futureIbis 146 4
Webster, M. S.Marra, P. P.Haig, S. M.Bensch, S.Holmes, R. T. 2002 Links between worlds: unraveling migratory connectivityTrends Ecol. Evol. 17 76
Wernham, C. V.Toms, M. P.Marchant, J. H. 2002 The Migration Atlas: Movements of the Birds of Britain and IrelandLondonPoyser
Whitfield, D. P. 2003 Predation by Eurasian sparrowhawks produces density-dependent mortality of wintering redshanksJ. Anim. Ecol. 72 27
Wolters, M.Bakker, J. P.Bertness, M. D.Jefferies, R. L.Möller, I. 2005 Saltmarsh erosion and restoration in south-east England: squeezing the evidence requires realignmentJ. Appl. Ecol. 42 844
Yates, M. G.Goss-Custard, J. D.McGrorty, S. 1993 Sediment characteristics, invertebrate densities and shorebird densities on the inner banks of the WashJ. Appl. Ecol. 30 599
Ydenberg, R. C.Butler, R. W.Lank, D. B.Smith, B. D.Ireland, J. 2004 Western sandpipers have altered migration tactics as peregrine falcon populations have recoveredProc. R. Soc. B 271 1263