Estuaries and Coasts

, Volume 38, Issue 4, pp 1251–1261 | Cite as

Rethinking the Freshwater Eel: Salt Marsh Trophic Support of the American Eel, Anguilla rostrata

  • Alyson L. EberhardtEmail author
  • David M. Burdick
  • Michele Dionne
  • Robert E. Vincent


Despite the fact that Anguilla rostrata (American eel) are frequently captured in salt marshes, their role in salt marsh food webs and the influence of human impacts, such as tidal restrictions, on this role remains unclear. To better understand salt marsh trophic support of A. rostrata, eels were collected from tidally restricted and unrestricted salt marsh creeks within three New England estuaries. Gut contents were examined, and eel muscle tissue was analyzed for carbon and nitrogen stable isotope values and entered into MixSir mixing models to understand if salt marsh food sources are important contributors to eel diet. Data suggest that eel prey rely heavily on salt marsh organic matter and eels utilize salt marsh secondary production as an energetic resource over time, and thus can be considered salt marsh residents. Gut contents indicate that A. rostrata function as top predators, feeding primarily on secondary consumers including other fish species, crustaceans, and polychaetes. Higher A. rostrata trophic position measured upstream of reference creeks suggests that severe tidal restrictions may result in altered food webs, but it is not clear how this impacts the overall fitness of A. rostrata populations in New England salt marshes.


Yellow eel Tidal marsh Tidal restriction Stable isotope Gut contents Mixing model 



The authors are grateful to Chris Peter, Chris Cavalieri, Carol Eberhardt, and Sandra Pimentel for field assistance, stable isotope sample preparation, and gut content analysis, and to Raymond Grizzle for assistance in identifying invertebrates in gut content samples. The authors also extend thanks to Andy Ouimette at the University of New Hampshire (UNH) Stable Isotope Laboratory for assistance in stable isotope sample analysis as well as Linda Deegan, Charles Hopkinson, and Hap Garritt for permission to use Quercus rubra and marine particulate organic matter stable isotope values. New Hampshire Sea Grant Development Funds, the UNH Marine Program William R. Spaulding Endowment, and the Natural Resources and Earth Systems Science doctoral program at UNH provided funding for this research. The Rachel Carson National Wildlife Refuge granted permission to sample in Wells, Maine.


  1. Adamowicz, S. and K. O’Brien. (2012). Drakes Island Tidal Restoration. In Tidal Marsh Restoration: A Synthesis of Science and Management, ed. C. Roman and D. Burdick, 315-332: Island Press/Center for Resource Economics.Google Scholar
  2. Aoyama, J., and M.J. Miller. 2003. The silver eel. In Eel Biology, ed. K. Aida, K. Tsukamoto, and K. Yamauchi, 107–117. Tokyo: Springer-Verlag.CrossRefGoogle Scholar
  3. Atlantic States Marine Fisheries Commission. (2000). Interstate fishery management plan for American eel (Anguilla rostrata). Atlantic States Marine Fisheries Commission, Washington, D.C. Fishery Management Report No. 36. 79 pp.Google Scholar
  4. Ayvazian, S.G., L.A. Deegan, and J.T. Finn. 1992. Comparison of habitat use by estuarine fish assemblages in the Acadian and Virginian zoogeographic provinces. Estuaries 15: 368–383.CrossRefGoogle Scholar
  5. Barse, A. M., and D. H. Secor. 1999. An exotic nematode parasite of the American eel. Fisheries 24:6–10.Google Scholar
  6. Béguer-Pon, M., J. Benchetrit, M. Castonguay, K. Aarestrup, and S.E. Campana. 2012. Shark Predation on Migrating Adult American Eels (Anguilla rostrata) in the Gulf of St. Lawrence. PLoS ONE 7(10): e46830.CrossRefGoogle Scholar
  7. Bolster, W.J. 2002. Cross-grained and wily waters. A guide to the Piscataqua maritime region. Portsmouth, N.H.: Peter E. RandallGoogle Scholar
  8. Bozeman, E.L., G.S. Helfman, and T. Richardson. 1985. Population size and home range of American eels in a Georgia tidal creek. Transactions of the American Fisheries Society 114: 821–825.CrossRefGoogle Scholar
  9. Bromberg, K., and M. Bertness. 2005. Reconstructing New England salt marsh losses using historical maps. Estuaries 28: 823–832.CrossRefGoogle Scholar
  10. Burdick, D.M., M. Dionne, R.M. Boumans, and F.T. Short. 1997. Ecological responses to tidal restorations of two northern New England salt marshes. Wetlands Ecology and Management 4: 129–144.CrossRefGoogle Scholar
  11. Burdick, D.M., R.M. Boumans, M. Dionne, and F.T. Short. 1999. Impacts to salt marshes from tidal restrictions and ecological responses to Tidal Restoration. Silver Spring: Final Report. NOAA Reserves and Sanctuaries Division.Google Scholar
  12. Burdick, D.B., C.R. Peter, G.E. Moore, and G. Wilson. 2010. Comparison of restoration techniques to reduce dominance of Phragmites australis at Meadow Pond, Hampton. Portsmouth: New Hampshire. Report to the New Hampshire Coastal Program.Google Scholar
  13. Chambers, R., L. Meyerson, and K. Dibble. (2012). Ecology of Phragmites australis and responses to tidal restoration. In Tidal marsh restoration: A synthesis of science and management, ed. C. Roman and D. Burdick, 81-96: Island Press/Center for Resource Economics.Google Scholar
  14. Clarke, K.R., and R.H. Green. (1988). Statistical design and analysis for a “biological effects” study.Google Scholar
  15. Deegan, L. 2004. Stable isotope (carbon and nitrogen) data for functional groups in the Plum Island Sound Estuary. Long Term Ecological Research Network. doi: 10.6073/pasta/d2af1a946689c48ece10b072b6ef1172.Google Scholar
  16. Deegan, L.A., and R.H. Garritt. 1997. Evidence for spatial variability in estuarine food webs. Marine Ecology Progress Series 147: 31–47.CrossRefGoogle Scholar
  17. Dibble, K., and L. Meyerson. 2013. The effects of plant invasion and ecosystem restoration on energy flow through salt marsh food webs. Estuaries and Coasts 1–15.Google Scholar
  18. Dionne, M., F. Short, and D. Burdick. 1999. Fish utilization of restored, created and reference salt-marsh habitat in the Gulf of Maine. American Fisheries Society Symposium 22: 384–404.Google Scholar
  19. Douglass, J.G., J.E. Duffy, and E.A. Canuel. 2011. Food web structure in a Chesapeake Bay eelgrass bed as determined through gut contents and 13C and 15N isotope analysis. Estuaries and Coasts 34: 701–711.CrossRefGoogle Scholar
  20. Eberhardt, A.L., D.M. Burdick, and M. Dionne. 2011. The Effects of Road Culverts on Nekton in New England Salt Marshes: Implications for Tidal Restoration. Restoration Ecology 19: 776–785.CrossRefGoogle Scholar
  21. Facey, D.E., and G.W. LaBar. 1981. Biology of American eels in Lake Champlain, Vermont. Transactions of the American Fisheries Society 110: 396–402.CrossRefGoogle Scholar
  22. Fell, P.E., K.A. Murphy, M.A. Peck, and M.L. Recchia. 1991. Re-establishment of Mylampus bidentatus (Say) and other macroinvertebrates on a restored impounded salt marsh: comparison of populations above and below the impoundment dyke. Journal of Experimental Marine Biology and Ecology 152: 33–48.CrossRefGoogle Scholar
  23. Ford, T.E., and E. Mercer. 1986. Density, size distribution, and home range of American eels, Anguilla rostrata, in a Massachusetts salt marsh. Environmental Biology of Fishes 17: 309–314.CrossRefGoogle Scholar
  24. Fry, B. 2006. Stable isotope ecology. New York: Springer.CrossRefGoogle Scholar
  25. Gillanders, B.M. 2005. Using elemental chemistry of fish otoliths to determine connectivity between estuarine and coastal habitats. Estuarine, Coastal and Shelf Science 64: 47–57.CrossRefGoogle Scholar
  26. Goode, A. 2006. The plight and outlook for migratory fish in the Gulf of Maine. Journal of Contemporary Water Research and Education 134: 23–28.Google Scholar
  27. Haro, A., W. Richkus, K. Whalen, A. Hoar, W.D. Busch, S. Lary, T. Brush, and D. Dixon. 2000. Population decline of the American eel: Implications for research and management. Fisheries 25: 7–16.CrossRefGoogle Scholar
  28. Helfman, G.S., D.L. Stoneburner, E.L. Bozeman, P.A. Christian, and R. Whalen. 1983. Ultrasonic telemetry of American eel movements in a tidal creek. Transactions of the American Fisheries Society 112: 105–110.CrossRefGoogle Scholar
  29. Hobson, K.A., and R.G. Clark. 1992. Assessing avian diets using stable isotopes 2. Factors influencing diet-tissue fractionation. Condor 94: 189–197.CrossRefGoogle Scholar
  30. Hyslop, E.J. 1980. Stomach contents analysis - A review of methods and their application. Journal of Fish Biology 17: 411–429.CrossRefGoogle Scholar
  31. Jessop, B.M. 1987. Migrating American eels in Nova Scotia. Transactions of the American Fisheries Society 116: 161–170.CrossRefGoogle Scholar
  32. Jessop, B.M. (1997). An overview of European and American eel stocks, fisheries and management issues. pp. 6-20. In R. H. Peterson (ed.). The American eel in eastern Canada: stock status and management strategies. Proceedings of Eel Workshop, January 13-14, 1997, Quebec City, Quebec. Biological Station. St. Andrews, NB. Canadian Technical Report of Fisheries and Aquatic Sciences. No. 2196. 174 pp.Google Scholar
  33. Jessop, B.M., J.C. Shiao, Y. Iizuka, and W.N. Tzeng. 2002. Migratory behavior and habitat use by American eels Anguilla rostrata as revealed by otolith microchemistry. Marine Ecology-Progress Series 233: 217–229.CrossRefGoogle Scholar
  34. Jessop, B.M., J.C. Shiao, Y. Iizuka, and W.N. Tzeng. 2004. Variation in the annual growth, by sex and migration history, of silver American eels Anguilla rostrata. Marine Ecology-Progress Series 272: 231–244.CrossRefGoogle Scholar
  35. Kneib, R.T. 1997. The role of tidal marshes in the ecology of estuarine nekton. Oceanography and Marine Biology: An Annual Review 35: 163–220.Google Scholar
  36. Layman, C.A., J.P. Quattrochi, C.M. Peyer, and J.E. Allgeier. 2007. Niche width collapse in a resilient top predator following ecosystem fragmentation. Ecology Letters 10: 937–944.CrossRefGoogle Scholar
  37. Levin, L.A., and C. Currin. (2012). Stable Isotope Protocols: Sampling and Sample Processing.Google Scholar
  38. Logan, J., H. Haas, L. Deegan, and E. Gaines. 2006. Turnover rates of nitrogen stable isotopes in the salt marsh mummichog, Fundulus heteroclitus, following a laboratory diet switch. Oecologia 147: 391–395.CrossRefGoogle Scholar
  39. McClelland, J.W., and I. Valiela. 1998. Changes in food web structure under the influence of increased anthropogenic nitrogen inputs to estuaries. Marine Ecology Progress Series 168: 259-271.Google Scholar
  40. Moore, J.W., and B.X. Semmens. 2008. Incorporating uncertainty and prior information into stable isotope mixing models. Ecology Letters 11: 470–480.CrossRefGoogle Scholar
  41. Morrison, W.E., D.H. Secor, and P.M. Piccoli. 2003. Estuarine habitat use by Hudson River American eels. American Fisheries Society Symposium 33: 87–99.Google Scholar
  42. Nelson, J.A., C.D. Stalling, W.M. Landing, and J. Chanton. 2013. Biomass transfer subsidizes nitrogen to offshore food webs. Ecosystems 16(6): 1130–1138.CrossRefGoogle Scholar
  43. Nixon, S.W., and C.A. Oviatt. 1973. Ecology of a New England salt marsh. Ecological Monographs 43: 463–498.CrossRefGoogle Scholar
  44. Odum, E.P. and A.A. de la Cruz. 1967. Particulate detritus in a Georgia salt marsh estuarine ecosystem. In Estuaries, ed. G.H. Lauff, 381-388. American Association for the Advancement of  Science Publication 83. Washington, D.C.Google Scholar
  45. Odum, W.E., J.S. Fisher, and J. Pickral. 1979. Factors controlling the flux of particulate organic carbon from estuarine wetlands. In Ecological processes in coastal and marine systems. Ecological Study Series, No. 10, ed. R.J. Livingston, 69–80. New York: Plenum.Google Scholar
  46. Ogden, J.C. 1970. Relative abundance, food habits, and age of the American eel, Anguilla rostrata (LeSueur), in certain New Jersey streams. Transactions of the American Fisheries Society 99: 54–59.CrossRefGoogle Scholar
  47. Oliveira, K. 1999. Life history characteristic and strategies of the American eel, Anguilla rostrata. Canadian Journal of Fisheries and Aquatic Sciences 56: 795–802.CrossRefGoogle Scholar
  48. Palstra, A. P., V. J. T. van Ginneken, A. J. Murk, and G. van den Thillart. 2006. Are dioxin-like contaminants responsible for the eel (Anguilla anguilla) drama? Naturwissenschaften 93:145–148.Google Scholar
  49. Persic, A., H.Roche, and F. Ramade. 2004. Stable carbon and nitrogen isotope quantitative structural assessment of dominant species from the Vaccarès Lagoon trophic web (Camargue Biosphere Reserve, France). Estuarine, Coastal and Shelf Science 60(2): 261–272.Google Scholar
  50. Pinnegar, J.K., and N.V.C. Polunin. 1999. Differential fractionation of delta C-13 and delta N-15 among fish tissues: implications for the study of trophic interactions. Functional Ecology 13: 225–231.CrossRefGoogle Scholar
  51. Roman, C., and D. Burdick. (2012). A Synthesis of Research and Practice on Restoring Tides to Salt Marshes. In Tidal Marsh Restoration: A Synthesis of Science and Management, ed. C. Roman and D. Burdick, 3-10: Island Press/Center for Resource Economics.Google Scholar
  52. Roman, C.T. and F.C. Daiber. 1989. Organic carbon flux through a Delaware Bay salt marsh: tidal exchange, particle size distribution, and storms. Marine Ecology Progress Series 54: 149–156.Google Scholar
  53. Roman, C. T., W. A. Niering, and R. S. Warren. 1984. Salt marsh vegetation change in response to tidal restriction. Environmental Management 8:141-150.Google Scholar
  54. Social Research for Sustainable Fisheries (SRSF). 2002. The Paq’tnkek Mi’kmaq and Kat American Eel - Anguilla rostrata) - A Preliminary Report of Research Results, Phase 1Google Scholar
  55. Sullivan, M.J., and C.A. Moncreiff. 1990. Edaphic algae are animportant component of salt marsh food webs: evidencefrom multiple stable isotope analyses. Marine Ecology Progress Series 62:149–159.Google Scholar
  56. Teal, J.M. 1962. Energy flow in the salt marsh ecosystem of Georgia. Ecology 43(4): 614–624.Google Scholar
  57. Tesch, F.W. 2003. The Eel. Oxford: Blackwell Science.CrossRefGoogle Scholar
  58. Tieszen, L.L., T.W. Boutton, K.G. Tesdahl, and N.A. Slade. 1983. Fractionation and turnover of stable carbon isotopes in animal tissues - implications for delta C13 analysis of diet. Oecologia 57: 32–37.CrossRefGoogle Scholar
  59. Tsukamoto, K., and T. Arai. 2001. Facultative catadromy of the eel Anguilla japonica between freshwater and seawater habitats. Marine Ecology-Progress Series 220: 265–276.CrossRefGoogle Scholar
  60. Tsukamoto, K., I. Nakai, and W.V. Tesch. 1998. Do all freshwater eels migrate? Nature 396: 635–636.CrossRefGoogle Scholar
  61. Tsukamoto, K., J. Aoyama, and M.J. Miller. 2002. Migration, speciation, and the evolution of diadromy in anguillid eels. Canadian Journal of Fisheries and Aquatic Sciences 59: 1989–1998.CrossRefGoogle Scholar
  62. Vander Zanden, M.J., and J.B. Rasmussen. 1999. Primary consumer d13C and d15N and the trophic position of aquatic consumers. Ecology 80: 1395–1404.CrossRefGoogle Scholar
  63. Vander Zanden, M.J., and J.B. Rasmussen. 2001. Variation in delta N-15 and delta C-13 trophic fractionation: Implications for aquatic food web studies. Limnology and Oceanography 46: 2061–2066.CrossRefGoogle Scholar
  64. Weisberg, S.B., and V.A. Lotrich. 1982. The importance of an infrequently flooded intertidal salt marsh surface as an energy source for the mummichog, Fundulus heteroclitus - an experimental approach. Marine Biology 66: 307–310.CrossRefGoogle Scholar
  65. Wenner, C., and J. Musick. 1975. Food habits and seasonal abundance of the American eel, Anguilla rostrata, from the lower Chesapeake Bay. Chesapeake Science 16: 62–66.CrossRefGoogle Scholar

Copyright information

© Coastal and Estuarine Research Federation 2015

Authors and Affiliations

  • Alyson L. Eberhardt
    • 1
    • 2
    Email author
  • David M. Burdick
    • 1
  • Michele Dionne
    • 3
  • Robert E. Vincent
    • 1
    • 4
  1. 1.Jackson Estuarine LaboratoryUniversity of New HampshireDurhamUSA
  2. 2.New Hampshire Sea Grant/UNH Cooperative ExtensionLeeUSA
  3. 3.Wells National Estuarine Research ReserveWellsUSA
  4. 4.MIT Sea Grant College ProgramCambridgeUSA

Personalised recommendations