WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2016 63 possible to place 5,178 t of limestone in rectangular ridges with triangular cross sections (1 m high with bases 2 m wide) in a culture area of 1.2 ha. Harvests could begin 3 to 5 years after substrate placement (Falls et al. 2003a). Assuming a 10 percent annual harvest of live rock from the 5,178 t of limestone riprap placed, 518 t of live rock could be harvested and sold each year. Harvested rock would be replaced annually. If native marine ornamental fish are stocked as an added species to create a more diverse reef community, a sustainable percentage of those fish could also be harvested for sales. A sufficiently large number/biomass of live rock organisms and fish must remain to reproduce and maintain a harvestable population. Biomass The objective is to create a large self-sustaining ecosystem to culture the desired native species. Water clarity and quality must be maintained as closely as possible to that found in the seawater of a healthy live reef environment. Limestone rocks of suitable size and shape for the aquarium trade are placed over the culture area. Natural benthic organisms and other marine life are allowed to colonize these rocks over a several year period. Some seeding of native Florida marine life from cultured and/or other legal sources may be needed to improve the variety of species found on the live rock. Marine ornamental fish and other valuable seawater animals/ plants could be stocked to enhance maintain a sustainable balance. The biomass of organisms encrusting the substrate might not be determined by available surface area. In addition to light, zooxanthellae and other reef algae need phosphorus, nitrogen and other nutrients. The total biomass of organisms found on live rock will depend on quarry productivity – the natural aquatic food supported by quarry water – determined by nutrient availability. It is not known how much live rock/coral the quarry can support without adding nutrients. The marine quarry has clear water, a good indicator that an aquatic environment has low nutrient concentration. Nutrient availability limits the amount of life the quarry can support. At low nutrient concentrations, biomass is determined by a self-sustaining (balanced) ecosystem. Carrying capacity will likely be controlled by nutrient availability and not oxygen demand. Too much nutrient input creates too much biomass. As the amount of available nutrient increases, the biomass increase is eventually limited by oxygen availability and respiration. To increase the biomass of live rock organisms and harvest yields beyond carrying capacity, nutrients would have to be added to the system. This could conceivably be done with some form of integrated multi-trophic aquaculture, but this could be a delicate and difficult balancing act. Quarry water nutrients should not exceed those found in a healthy reef environment. Nutrient levels above natural concentrations could be detrimental to live rock and coral production by decreasing water clarity. Opportunity The quarry represents an opportunity for commercial aquaculture. Compared to open coastal waters, the quarry may provide a relatively stable environment that is potentially more sheltered from the impacts of storms. Marine limestone quarries can be used to create live reef/coral preserves. Placed substrate would be used to create artificial reefs for corals and other reef organisms that are or may become threatened or endangered. With the global decline of living coral reefs, the value of live rock aquaculture in quarries for preservation may be greater than that for profit. Notes William A. Wurts, Aquaculture Specialist, 201 Apache Drive, Princeton, KY 42445-1165 wawurts@gmail.com Acknowledgments I gratefully acknowledge the University of Kentucky for providing post-retirement office space and resources as well as staff and technical support while developing this manuscript. In addition to the scientists cited for providing data, I gratefully acknowledge Dr. Jim Hendee with the National Oceanographic and Atmospheric Administration and Scott Donahue with the Florida Keys National Marine Sanctuary who guided me in my search for Looe Key Reef data. References Briceno, H.O. 2015. Looe Key attenuation coefficient data, 19952014, provided by the SERC-FIU Water Quality Monitoring Network which is supported by EPA Agreement #US EPA Agreement #X7 00D0241 Bold, H.C. and M.J. Wynne. 1978. Introduction to the Algae: Structure and Reproduction. Prentice Hall Prentice-Hall, Inc., Englewood Cliffs, NJ, 706 pp. Clark, G.L. and E.J. Denton. 1962. Light and animal life. Pages 456-468 In: M.N. Hill, editor. The Sea, Vol. 1. John Wiley and Sons, New York, NY. USA Falls, W.W., J.N. Ehringer, R. Herndon, T. Herndon, M.S. Nichols, S. Nettles, C. Armstrong and D. Haverkamp. 2003a. Aquaculture of live rock: and eco-friendly alternative. World Aquaculture 34(2):39-44. Falls, W.W., J.N. Ehringer and P. Stinnette. 2003b. Live rock aquaculture. Final report prepared for the National Science Foundation. Gramer, L.J. 2015. Moored current velocity and temperature data provided by NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL. Johns, E.M. 2015. Moored salinity data provided by NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL. Lidz, B. H., D. M . Robbin and E.A. Shinn. 1985. Holocene carbonate sedimentary petrology and facies accumulation, Looe Key National Marine Sanctuary, Florida. Bulletin of Marine Science 36(3):672-700. NCDC (National Climatic Data Center). 1998. Climatic wind data for the United States. National Climatic Data Center (NCDC)/ NOAA. Weber, J. E. 1983. Steady wind- and wave-induced currents in the open ocean. Journal of Physical Oceanography 13:524–530. Wheaton, J.L., W.C. Jaap, P. Dustan, J. Porter and O. Meier. 1996. Florida Keys National Marine Sanctuary water quality protection plan coral reef and hard bottom monitoring project annual report (10/1/95-9/30/96).
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