Biorock® oyster and saltmarsh restoration after oil spills: Fastest growth, highest survival

Thomas J. Goreau, PhD
President Global Coral Reef Alliance

Biorock® restoration is the only method known that 1) increases growth rates of oysters and saltmarsh grass (allowing accelerated restoration of damaged areas), 2) increases their resistance to environmental stress (often allowing them to be kept alive where they would die), 3) extends their growth beyond their normal environmental ranges, and 4) may also help speed breakdown of oil residues in the water and sediment.

North American oysters (Crassostrea virginica) grown on Biorock® grew about two times faster and had about half the mortality of controls (1). Biorock® saltmarsh grass (Spartina alterniflora) grew nearly two times faster in height, had about twice as many stalks, and grew under conditions too deeply submerged for this grass to normally survive, that is to say beyond its normal limit (2).

Saltmarshes and oyster reefs are the major ecosystems that will need to be restored in Louisiana and around the Gulf of Mexico after the oil spills have ended. Biorock is the only method that increases oyster and saltmarsh growth rates, so Biorock restoration projects will be the fastest way to restore oil damaged habitat.

The first Biorock projects by the late Professor Wolf Hilbertz, done in the mid 1970s in Grand Isle, the very area of the Mississippi delta in Louisiana now affected by oil spills, were completely covered by multiple layers of exceptionally rapidly-growing, spontaneously-settling, oysters within months. There is little doubt that Biorock will not only bring these critical ecosystems back faster if they are damaged, it might also allow saltmarsh and oyster reefs to be extended seaward of their normal limits, protecting the coast from further erosion.

Because Biorock confers much higher stress resistance, use of Biorock technology might allow existing oyster reefs and saltmarshes to be protected from severe mortality if put in place BEFORE the oil arrives.

Biorock is also the best solution for restoring coral reefs affected by oil. Biorock corals grow 2-6 times faster than controls and had 16 to 50 times higher survival following severe high temperature stress (3). Coral reefs of the Gulf of Mexico, Florida, the Bahamas, and Cuba could be impacted by oil in coming months.

Biorock reefs grow eroding beaches back quickly (4) and provide exceptional fisheries habitat (5). In addition there is an excellent chance that adaptation of Biorock methods could also accelerate microbial degradation of oil residues in sediments, although further work is needed to develop this application.

REFERENCES

1. N. Berger, J. T. Boehm, M. Haseltine, & T. Goreau, Oyster Growth study using Biorock Technology, to appear in T. Goreau (Ed.) Marine Habitat Restoration, special session of the 2011 World Restoration Conference.

2. J. Cervino, C. Zeckendorf, & T. Goreau, Electrical stimulation increases growth of saltmarsh grass Spartina alterniflora, to appear in T. Goreau (Ed.) Marine Habitat Restoration, special session of the 2011 World Restoration Conference.

3. T. Goreau & W. Hilbertz, 2009, Coral reef restoration for adaptation to global warming, 8 p., in T. J. Goreau & S. T. Nielsen (Eds.), The Green Disc: New Technologies for a New Future, Gibby Media Group, Spokane WA.

4. W. Hilbertz & T. Goreau, 2009, Shore protection from global sea level rise, 9p., in T. J. Goreau & S. T. Nielsen (Eds.), The Green Disc: New Technologies for a New Future, Gibby Media Group, Spokane WA.

5. T. Goreau & W. Hilbertz, 2009, Fisheries habitat restoration, 10p., in T. J. Goreau & S. T. Nielsen (Eds.), The Green Disc: New Technologies for a New Future, Gibby Media Group, Spokane WA.

For more information on all of these applications, please contact Dr. Thomas J. Goreau at goreau@bestweb.net