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The impacts of the 2004 hurricanes on hydrology, water quality, and seagrass in the Central Indian River Lagoon, Florida


Between August 14 and September 26, 2004, four tropical weather systems (Charley, Frances, Ivan, and Jeanne) affected the central Indian River Lagoon (IRL). The central IRL received a prodigious amount of rainfall for the 2 mo, between 72 and 83 cm, which is a once-in-50-yr rainfall event. High stream discharges were generated that, combined with wind-suspended sediments, significantly reduced salinities and water transparency. In September, salinities among central IRL segments dropped from 30 psu or more to ≤15 psu, color increased from a low of 10 pcu to ≥100 pcu, and turbidity increased from ≤3 NTU up to 14 NTU. Evidence of the hurricanes' physical effects on seagrasses (burial, no scour) was limited to just one of the more than 25 sites inspected. Within 2 to 3 mo following the hurricane period, most parameters related to water transparency returned to or showed improvement over their prehurricane (February–July 2004) levels. Unseasonably low salinities (<20 psu) and moderately high color (>20 pcu) were observed through spring 2005, largely attributable to a relatively long residence time and a wetter-than-average spring season in 2005. By the end of the study period (July 2006), the central IRL generally showed a continuation of two opposite seagrass trends—an increase in depthlimit coverage but a decline in coverage density—that began before 2004. Also, within a limited reach of the central IRL, there was a temporary shift in species composition in summer 2005 (Ruppia maritima increased asHalodule wrightü decreased). It is likely that the persistently low salinities (not color) in 2004–2005 affected the species composition and coverage density. This study reveals that seagrasses are resilient to the acute effects of hurricanes and underscores the need to reduce chronic, an thropogenic effects on seagrasses.

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Literature Cited

  1. Christian, D. 2004. Indian River Lagoon Flushing. St. Johns River Water Management District Technical Memorandum. St. John River Water Management District, Palatka, Florida.

    Google Scholar 

  2. Coastal Planning and Engineering. 1997. Indian River Lagoon bathymetric survey. A final report to St. Johns River Water Management District, Contract #95W142, Palatka, Florida.

  3. Dobson, J. E., E. A. Bright, R. L. Ferguson, D. W. Field, L. L. Wood, K. D. Haddad, H. Iredale, III,R. R. Jensen, V. V. Klemas, R. J. Orth, andJ. P. Thomas. 1995. NOAA Coastal Change Analysis Program (C-CAP) for Regional Implementation. NOAA Technical Report NMFS 123. NOAA, Silver Spring, Maryland.

    Google Scholar 

  4. Gallegos, C. L. 1993. Determination of optical water quality requirements for growth of seagrasses in the Indian River near Ft. Pierce, FL, with emphasis on the impact of colored water discharges. Report to South Florida Water Management District, Contract # C-3311, West Plam Beach, Florida.

    Google Scholar 

  5. Gallegos, C. L. andW. J. Kenworthy. 1996. Seagrass depth limits in the Indian River Lagoon (Florida, U.S.A.): Application of an optical water quality model.Estuarine Coastal and Shelf Science 42: 267–288.

    Article  Google Scholar 

  6. Gilmore, R. G. 1995. Environmental and biogeographic factors influencing ichthyofaunal diversity: Indian River Lagoon.Bulletin of Marine Science 57:153–170.

    Google Scholar 

  7. Hanisak, M. D. 2001. Photosynthetically active radiation, water quality, and submerged aquatic vegetation in Indian River Lagoon. Final report to St. Johns River Water Management District, Contract #93W199, Palatka, Florida.

  8. Heck, Jr., K. L. and D. Byron. 2005. Post-Hurricane Ivan damage assessment of seagrass resources of coastal Alabama. Dauphin Island Sea Lab report, Dauphin Island, Alabama.

  9. Indian River Lagoon National Estuary Program. 1996. The Indian River Lagoon Comprehensive Conservation and Management Plan. St. Johns River Water Management District and South Florida Water Management District and U.S. Environmental Protection Agency. Palm Bay, Florida.

    Google Scholar 

  10. Kenworthy, W. J. and D. E. Haunert. 1991. The Light Requirements of Seagrasses: Proceedings of a Workshop to Examine the Capability of Water Quality Criteria. Standards, and Monitoring Programs to Protect Seagrasses. NOAA Technical memorandum, NMFS-SEFC-287. Washington, D.C.

  11. Knowles, Jr., L. 1995. Rainfall and freshwater discharge in the Indian River basin within the St. Johns River Water Management District, east-central Florida, 1989–91. U.S. Geological Survey Water-Resources Investigations Report 94-4193. Tallahassee, Florida.

  12. Michot, T. C., J. N. Burch, A. Arrivillaga, P. S. Rafferty, T. W. Doyle, andR. S. Kemmerer. 2002. Impacts of Hurricane Mitch on seagrass beds and associated shallow reef communities along the Caribbean coast of Honduras and Guatemala. U.S. Geological Survey Open File Report 03-181, National Wetlands Research Center, Lafayette, Louisiana.

    Google Scholar 

  13. Montague, C. L. andJ. A. Ley. 1993. A possible effect of salinity fluctuation on abundance of benthic vegetation and associated fauna in northeastern Florida Bay.Estuaries 16:703–717.

    Article  CAS  Google Scholar 

  14. Morris, L. J., L. M. Hall, andR. W. Virnstein. 2001. Field guide for fixed seagrass transect monitoring in the Indian River Lagoon. St. Johns River Water Management District, Palatka, Florida.

    Google Scholar 

  15. Morris, L. J. andD. A. Tomasko (eds.). 1993. Proceedings and conclusions of workshops on: Submerged aquatic vegetation and photosynthetically active radiation. St. Johns River Water Management District, Special Publication SJ93-SP13. Palatka, Florida.

  16. Morrison, D., J. Malsi, P. Renault, P. Light, and C. Marx. 1989. Impact of freshwater discharge from finger canals on estuarine seagrass and mangrove ecosystems in southwest Florida. Final Report, Florida Department of Environmental Regulation Contract CM-230. City of Cape Coral, Florida.

  17. Phillips, R. C. 1960. Observations on the ecology and distribution of the Florida seagrasses. Florida State Board of Convervation Marine Laboratory, Professional Paper Series #2. St. Petersburg, Florida.

  18. Provancha, J. A. and D. M. Scheidt. 2000. Long-term trends in seagrass beds in the Mosquito lagoon and northern Banana River, Florida, p. 211–218.In S. A. Bortone (ed.), Seagrasses: Monitoring, Ecology, Physiology, and Management. CRC Press Marine Science Series, Boca Raton, Florida.

  19. Saloman, C. H. andS. P. Naughton. 1977. Effect of Hurricane Eloise on the benthic fauna of Panama City beach, Florida, USA.Marine Biology 42:357–363.

    Article  Google Scholar 

  20. Sheng, Y. P. andJ. R. Davis. 2003. Indian River Lagoon Pollutant Load Reduction (IRLPLR) model development project, Volume 1, A 3-D IRL hydrodynamics/salinity model (UF-CH3D). University of Florida, Civil and Coastal Engineering Department, Gainesville, Florida.

    Google Scholar 

  21. Sigua, G., W. A. Tweedale, J. D. Miller, and J. S. Steward. 1996. Inter-agency implementation of a modified water quality monitoring program for the Indian River Lagoon: Methods and QA/QC Issues. St. Johns River Water Management District Technical Memorandum #19. Palatka, Florida.

  22. Smith, N. P. 1987. An introduction to the tides of Florida's Indian River Lagoon. I. Water levels.Florida Scientist 50:49–61.

    CAS  Google Scholar 

  23. Smith, N. P. 1993. Tidal and nontidal flushing of the Florida's Indian River Lagoon.Estuaries 16:739–746.

    Article  Google Scholar 

  24. Smith, N. P. 2001. Seasonal-scale transport patterns in a multiinlet coastal lagoon.Estuarine Coastal and Shelf Science 52:15–28.

    Article  Google Scholar 

  25. Steward, J. S., R. Brockmeyer, R. Virnstein, P. Gostel, P. Sime, andJ. VanArman. 2003. Indian River Lagoon Surface Water Improvement and Management (SWIM) Plan, 2002 Update. St. Johns River Water Management District, Palatka, Florida, and South Florida Water Management District, West Palm Beach, Florida.

    Google Scholar 

  26. Steward, J. S., D. Haunert, F. Lund, andR. Virnstein. 1994. IRL Surface Water Improvement and Management (SWIM) Plan (update). St. Johns River Water Management District, Palatka, Florida: and South Florida Water Management District, West Palm Beach, Florida.

    Google Scholar 

  27. Steward, J. S., andJ. Vanarman. 1987. The Indian River Lagoon Joint Reconnaissance Report. A report to Florida Office of Coastal Management of the Florida Department of Environmental Regulation, and NOAA Office of Coastal Resource Management. St. Johns River and South Florida Water Management Districts. Palatka and West Palm Beach, Florida.

    Google Scholar 

  28. Steward, J. S., R. W. Virnstein, L. J. Morris, andE. F. Lowe. 2005. Setting seagrass depth, coverage, and light targets for the Indian River Lagoon system, Florida.Estuaries 28:923–935.

    Article  Google Scholar 

  29. Thompson, M. J. 1976. Photomapping and species composition of the seagrass beds in Florida's Indian River estuary. Harbor Branch Foundation, Inc. Technical Report # 10. Ft. Pierce, Florida.

  30. Thompson, M. J. 1978. Species composition and distribution of seagrass beds in the Indian River Lagoon, Florida.Florida Scientist 41:90–96.

    Google Scholar 

  31. Virnstein, R. W. 1990. The large spatial and temporal biological variability of the Indian River Lagoon.Florida Scientist 53:249–256.

    Google Scholar 

  32. Virnstein, R. W. 2000. Seagrass management in Indian River Lagoon, Florida: Dealing with issues of scale.Pacific Conservation Biology 5:299–305.

    Google Scholar 

  33. Virnstein, R. W., E. W. Carter Iv, L. J. Morris, and J. D. Miller. 2000. Utility of seagrass restoration indices based on area, depth, and light, p. 69–80.In Proceedings of a Symposium: Seagrass Management: It's Not Just Nutrients! St. Petersburg, Florida.

  34. Virnstein, R. W. and L. J. Morris. 1996. Seagrass preservation and restoration: A diagnostic plan for the Indian River Lagoon. St. Johns River Water Management District, Technical Memorandum No. 14. Palatka, Florida.

  35. Woodward-Clyde Consultants, Marshall McCully and Associates, and Natural Systems Analysists. 1994. Physical features of the Indian River Lagoon. Final Technical Report to the Indian River lagoon National Estuary Program, Melbourne, Florida.

Sources of Unpublished Materials

  1. Doering, Peter, personal communication. South Florida Water Management District, 3301 Gun Club Road, West Palm Beach. Florida 33406.

  2. Sheikh, P. A. 2005. The impact of Hurricane Katrina on biological resources. Congressional Research Service Report for Congress. Order Code RL33117

  3. St. Johns River Water Management District (SJRWMD). unpublished data. Hydrologic results. 4049 Reid Street, Palatka, Florida 32177.

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Correspondence to Joel S. Steward.

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Steward, J.S., Virnstein, R.W., Lasi, M.A. et al. The impacts of the 2004 hurricanes on hydrology, water quality, and seagrass in the Central Indian River Lagoon, Florida. Estuaries and Coasts: J ERF 29, 954–965 (2006).

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  • Secchi Depth
  • Indian River Lagoon
  • South Florida Water Management District
  • Transect Length
  • Seagrass Coverage