Sargassum and Beach Erosion: Potential Costs and Benefits for Coastal Managers: final report.

Abstract

Sargassum fluitans and natans, types of brown algae wash up on Galveston Island, Texas each year from May to August. Sargassum smells bad, hurts tourism and impairs sea turtle hatchings. Coastal managers are confronted with the difficult choice of cleaning Sargassum off the beach front or leaving it alone. The current beach management practice is to rake the algae with mechanical tractors and deposit it at the base of the dunes. The environmental impacts of raking and ecological benefits of Sargassum are unknown. The Galveston Island Park Board of Trustees (GIPBT) used to rake all beaches under their management before Hurricane Alicia in 1983. Then, citizens started to complain that raking was causing erosion. Now, there are people who argue for raking and leaving the beach alone. Environmental policies require complex decisions that take into consideration social, economical, ecological, and cultural values. The GIPBT initiated the Sargassum Policy Committee to gain knowledge of different stakeholder values to develop beach cleaning policies. Scientific research will also be used to make decisions. The first study analyzed elevation changes over a year period on raked and unraked beaches on Galveston Island on both the West and the East end of the island. The Analysis of Variance results indicated that there is not a difference in elevation changes between the raked and unraked beaches over a year