, Volume 693, Issue 1, pp 1–11 | Cite as

Ferry wakes increase seaweed richness and abundance in a sheltered rocky intertidal habitat

  • Kyle W. DemesEmail author
  • Rebecca L. Kordas
  • Jennifer P. Jorve
Primary Research Paper


Because hydrodynamic regimes influence community assemblages, commercial ferry traffic can directly affect neighboring marine ecosystems by altering water movement. One of the largest ferry fleets in the world traverses the calm, protected waters of the Canadian Gulf Islands (British Columbia). To address the effects of ferry wakes on rocky marine intertidal communities, we examined community assemblages in sites impacted by ferry wakes (N = 5) relative to geographically similar control sites not directly exposed to ferry wakes (N = 6). Intertidal communities were significantly different between wake-influenced and control sites. Further analyses revealed that community level differences resulted from differences in seaweed assemblages, while invertebrate assemblages were similar. Sites exposed to ferry traffic displayed significantly greater overall seaweed abundance and seaweed species richness. Nitrate and nitrite concentrations, salinity, fetch, and tidal zonation were not significantly different between wake-impacted and control sites. However, dissolution blocks revealed that wake-impacted sites experienced increased overall water movement. Furthermore, block dissolution was negatively associated with distance from nearest ferry route and not fetch. Although dissolution block cannot disentangle effects of increased flow versus waves resulting from ferry wakes, we conclude that increased overall water movement from frequent and proximate ferry traffic stimulates primary production in rocky intertidal marine seaweeds by ameliorating mass transfer limitation.


British Columbia Diversity Ferry wakes Flow Marine Mass transfer 



The authors would like to thank Chris Harley, Kerry Nickols, Stefan Storey, and Emily Carrington for their helpful comments throughout the course of this project; Mike Burrows, Ally Thompson, and Chris Lee for their help with the map creation and fetch analyses; and Mary O’Connor, Rebecca Martone, Jonathan Pruitt, and Helen Demes for their constructive criticism on earlier versions of this manuscript. Funding was provided by the National Science and Engineering Research Council grant to Christopher Harley.


  1. Biber, P. D. & E. A. Irlandi, 2006. Temporal and spatial dynamics of macroalgal communities along an anthropogenic salinity gradient in Biscayne Bay (Florida, USA). Aquatic Botany 85: 65–77.CrossRefGoogle Scholar
  2. Bishop, M. J., 2005. Compensatory effects of boat wake and dredge spoil disposal on assemblages of macroinvertebrates. Estuaries 28(4): 510–518.CrossRefGoogle Scholar
  3. Bishop, M., 2007. Impacts of boat-generated waves on macroinfauna: Towards a mechanistic understanding. Journal of Experimental Marine Biology and Ecology 343: 187–196.CrossRefGoogle Scholar
  4. Bishop, M. & M. Chapman, 2004. Managerial decisions as experiments: an opportunity to determine the ecological impact of boat-generated waves on macrobenthic infauna. Estuarine, Coastal and Shelf Science 61: 613–622.CrossRefGoogle Scholar
  5. Boizard, S. D. & R. E. DeWreede, 2006. Inexpensive water motion measurement devices and techniques and their utility in macroalgal ecology: a review. Science Asia 32: 43–49.CrossRefGoogle Scholar
  6. Blamey, L. K. & G. M. Brance, 2009. Habitat diversity relative to wave action on rocky shores: implications for the selectin of marine protected area. Aquatic Conservation: Marine and Freshwater Ecosystems 19: 645–657.CrossRefGoogle Scholar
  7. Burrows, M. T., R. Harvey & L. Robb, 2008. Wave exposure indices from digital coastlines and the prediction of rocky shore community structure. Marine Ecology Progress Series 353: 1–12.CrossRefGoogle Scholar
  8. Burkepile, D. E. & M. E. Hay, 2006. Herbivore vs. nutrient control of marine primary producers: context-dependent effects. Ecology 87(12): 3128–3139.PubMedCrossRefGoogle Scholar
  9. Bustamante, R. & G. Branch, 1996. Large scale patterns and trophic structure of southern African rocky shores: the roles of geographic variation and wave exposure. Journal of Biogeography 23: 339–351.CrossRefGoogle Scholar
  10. Carpenter, R. C. & S. L. Williams, 2007. Mass transfer limitation of photosynthesis of coral reef algal turfs. Marine Biology 151: 435–450.CrossRefGoogle Scholar
  11. Carrington, E., 1990. Drag and dislodgement of an intertidal macroalga: consequences of morphological variation in Mastocarpus papillatus Kützing. Journal of Experimental Marine Biology and Ecology 139: 185–200.CrossRefGoogle Scholar
  12. Connell, J. H., 1978. Diversity in Tropical Rain Forests and Coral Reefs High diversity of trees and corals is maintained. Science 199(4335): 1302–1310.PubMedCrossRefGoogle Scholar
  13. Denny, M. W., 1988. Biology and the Mechanics of the Wave-Swept Environment. Cambridge University Press, Cambridge, UK.Google Scholar
  14. Denny, M. W., 1993. Air and Water: The Biology and Physics of Life’s Media. Princeton University Press, Princeton, USA.Google Scholar
  15. Denny, M. W., L. P. Miller, M. D. Stokes, L. J. H. Hunt & B. S. T. Helmuth, 2003. Extreme water velocities: topographical amplification of wave-induced flow in the surf zone of rocky shores. Limnology and Oceanography 48: 1–8.CrossRefGoogle Scholar
  16. Eriksson, B. K., A. Sandström, M. Isæus, H. Schreiber & P. Karås, 2004. Effects of boating activities on aquatic vegetation in the Stockholm archipelago, Baltic Sea. Estuarine Coastal and Shelf Science 61: 339–349.CrossRefGoogle Scholar
  17. Foster, M. S., 1975. Algal succession in a Macrocystis pyrifera forest. Marine Biology 32: 313–329.CrossRefGoogle Scholar
  18. Gabel, F., X.-F. Garcia, M. Brauns, A. Sukhodolov, M. Leszinski & M. T. Pusch, 2008. Resistance to ship-induced waves of benthic invertebrates in various littoral habitats. Freshwater Biology 53: 1567–1578.CrossRefGoogle Scholar
  19. Gabel, F., S. Stoll, P. Fischer, M. T. Pusch & X.-F. Garcia, 2011. Waves affect predator–prey interactions between fish and benthic invertebrates. Oecologia 165: 101–109.PubMedCrossRefGoogle Scholar
  20. Gabrielson, P. W., T. B. Widdowson, S. C. Lindstrom, 2006. Keys to the Seaweeds and Seagrasses of Southeast Alaska, British Columbia, Washington, and Oregon. University of British Columbia Dept. of Botany (Phycological contributions), Vancouver, Canada.Google Scholar
  21. Gerard, V. A., 1984. The light environment in a giant kelp forest: influence of Macrocystis pyrifera on spatial and temporal variability. Marine Biology 84: 189–195.CrossRefGoogle Scholar
  22. Harley, C. D. G. & B. S. T. Helmuth, 2003. Local- and regional-scale effects of wave exposure, thermal stress, and absolute versus effective shore level on patterns of intertidal zonation. Limnology and Oceanography 48: 1498–1508.CrossRefGoogle Scholar
  23. Hay, M. E., 1986. Functional geometry of seaweeds: ecological consequences of thallus laying and shape in contrasting light environments. In Givnish, T. J. (ed.), On the Economy of Plant Form and Function. Cambridge University Press, Cambridge: 635–666.Google Scholar
  24. Hay, M. E. & W. Fenical, 1988. Marine plant-herbivore interactions: the ecology of chemical defense. Annual Review Ecology and Systematics 19: 111–145.CrossRefGoogle Scholar
  25. Hurd, C. L., P. J. Harrison & L. D. Druehl, 1996. Effect of seawater velocity on inorganic nitrogen uptake by morphologically distinct forms of Macrocystis integrifolia from wave-sheltered and exposed sites. Marine Biology 126: 205–214.CrossRefGoogle Scholar
  26. Hurd, C. L. & C. I. Stevens, 1997. Flow visualization around single- and multiple-bladed seaweeds with various morphologies. Journal of Phycology 33: 360–367.CrossRefGoogle Scholar
  27. Kautsky, L. & H. Kautsky, 1989. Algal species diversity and dominance along gradients of stress and disturbance in marine environments. Vegetatio 83: 259–267.CrossRefGoogle Scholar
  28. Koehl, M. A. R., W. K. Silk, H. Lian & L. Mahadevan, 2008. How kelps produce blade shapes suited to different flow regimes: a new wrinkle. Integrative and Comparative Biology 48: 834–851.PubMedCrossRefGoogle Scholar
  29. Lapointe, B. E., 1997. Nutrient thresholds for bottom-up control of macroalgal Jamaica and southeast Florida. Limnology and Oceaongraphy 42: 1119–1131.CrossRefGoogle Scholar
  30. Lapointe, B. E., 1999. Simultaneous top-down and bottom-up forces control macroalgal blooms on coral reefs (Reply to the comment by Hughes et al.). Limnology and Oceanography 44(6): 1586–1592.Google Scholar
  31. Lenihan, H. S., C. H. Peterson & J. M. Allen, 1996. Does flow speed also have a direct effect on growth of active suspension-feeders: an experimental test on oysters. Limnology and Oceanography 41: 1359–1366.CrossRefGoogle Scholar
  32. Leonard, G. H., J. M. Levine, P. R. Schmidt & M. D. Bertness, 1998. Flow-driven variation in intertidal community structure in a Maine estuary. Ecology 79: 1395–1411.CrossRefGoogle Scholar
  33. Lubchenco, J., 1978. Plant species diversity in a marine intertidal community: Importance of herbivore food preference and algal competitive abilities. American Naturalist 112: 23–39.CrossRefGoogle Scholar
  34. Lubchenco, J., 1980. Algal zonation in the New England rocky intertidal community: an experimental analysis. Ecology 61: 333–344.CrossRefGoogle Scholar
  35. Mass, T., A. Genin, U. Shavit, M. Grinstein & D. Tchernov, 2010. Flow enhances photosynthesis in marine benthic autotrophs by increasing the efflux of oxygen from the organism to the water. Proceedings of the National Academy of Sciences 107(6): 2527–2531.CrossRefGoogle Scholar
  36. McQuaid, C. D. & G. M. Branch, 1984. Influence of sea temperature, substratum, and wave exposure on rocky intertidal communities: an analysis of faunal and floral biomass. Marine Ecology Progress Series 19: 145–151.CrossRefGoogle Scholar
  37. Menge, B., 2000. Top-down and bottom-up community regulation in marine rocky intertidal habitats. Journal of Experimental Marine Biology and Ecology 250: 257–289.PubMedCrossRefGoogle Scholar
  38. Nishihara, G. N. & R. Terada, 2010. Species richness of marine macrophytes is correlated to a wave exposure gradient. Phycological Research 58: 280–292.CrossRefGoogle Scholar
  39. Parnell, K. & H. Kofoed-Hansen, 2001. Wakes from large high-speed ferries in confined coastal waters: management approaches with examples from New Zealand and Denmark. Coastal Management 29: 217–237.CrossRefGoogle Scholar
  40. Patterson, M. R., 1992. A mass transfer explanation of metabolic scaling relations in some aquatic invertebrates and algae. Science 255(5050): 1421.PubMedCrossRefGoogle Scholar
  41. Rönnberg, O., 1975. The effects of ferry traffic on rocky shore vegetation in the southern Åland Archipelgao. Merentutkimuslait Julk Havsforskningsinst Skr 239: 325–330.Google Scholar
  42. Soomere, T., 2005. Fast ferry traffic as a qualitatively new forcing factor of environmental processes in non-tidal sea areas: a case study in Tallinn Bay, Baltic Sea. Environmental Fluid Mechanics 5: 293–323.CrossRefGoogle Scholar
  43. Soomere, T., 2009. Long ship waves in shallow water bodies. In Quak, E. & T. Soomere (eds), Applied Wave Mathematics. Springer, Berlin: 193–227.CrossRefGoogle Scholar
  44. Soomere, T., K. E. Parnell & I. Didenkulova, 2009. Implications of fast-ferry wakes for semi-sheltered beaches: a case study at Aegna Island, Baltic Sea. Journal of Coastal Research 56: 128–132.Google Scholar
  45. Steneck, S. & M. N. Dethier, 1994. A functional group approach to the structure of algal-dominated communities. Oikos 69(3): 476–498.CrossRefGoogle Scholar
  46. Steneck, R. S. & L. Watling, 1982. Feeding capabilities and limitation of herbivorous mollusks: a functional group approach. Marine Biology 68: 299–319.CrossRefGoogle Scholar
  47. Stephenson, T. A. & A. Stephenson, 1949. The universal features of zonation between tide-marks on rocky coasts. Journal of Ecology 37(2): 289–305.CrossRefGoogle Scholar
  48. Stevens, C. L. & C. L. Hurd, 1997. Boundary-layers around bladed aquatic macrophytes. Hydrobiologia 346: 119–128.CrossRefGoogle Scholar
  49. Stewart, H. L. & R. C. Carpenter, 2003. The effects of morphology and water flow on photosynthesis of marine macroalgae. Ecology 84(11): 2999–3012.CrossRefGoogle Scholar
  50. Thomas, F. I. M., C. D. Cornelisen & J. M. Zande, 2000. Effects of water velocity and canopy morphology on ammonium uptake by seagrass communities. Ecology 81(10): 2704–2713.CrossRefGoogle Scholar
  51. Thompson, T. L. & E. P. Glenn, 1994. Plaster standards to measure water motion. Limnology and Oceaongraphy 39: 1768–1779.CrossRefGoogle Scholar
  52. Thomsen, M. S., T. Wernberg & G. A. Kendrick, 2004. The effect of thallus size, life stage, aggregation, wave exposure and substratum conditions on the forces required to break or dislodge the small kelp Ecklonia radiata. Botanica Marina 47: 454–460.CrossRefGoogle Scholar
  53. Trager, G., Y. Achituv & A. Genin, 1994. Effects of prey escape ability, flow speed, and predator feeding mode on zooplankton capture by barnacles. Marine Biology 120: 251–259.CrossRefGoogle Scholar
  54. Wall, L. M., L. J. Walters, R. E. Grizzle & P. E. Sacks, 2005. Recreational boating activity and its impact on the recruitment and survival of the oyster Crassostra virginica on intertidal reefs in Mosquito Lagoon, Florida. Journal of Shellfish Research 24(4): 965–973.Google Scholar
  55. Willby, N. J., J. R. Pygott & J. W. Eaton, 2001. Inter-relationships between standing crop, biodiversity and trait attributes of hydrophytic vegetation in artificial waterways. Freshwater Biology 46: 883–902.CrossRefGoogle Scholar
  56. Wing, S. R. & M. R. Patterson, 1993. Effects of wave-induced lightflecks in the intertidal zone on photosynthesis in the macroalgae Postelsia palmaeformis and Hedophyllum sessile (Phaeophyceae). Marine Biology 116: 519–525.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Kyle W. Demes
    • 1
    Email author
  • Rebecca L. Kordas
    • 1
  • Jennifer P. Jorve
    • 1
  1. 1.Department of ZoologyUniversity of British ColumbiaVancouverCanada

Personalised recommendations