WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2016 61 and creatures has become its own specialized tropical marine aquarium industry. Growing live rock and coral for retail and wholesale markets represents a good low-management, low-technology aquaculture business option for a marine quarry. Small-scale ornamental marine fish production could integrate well with live-rock aquaculture. The potential impact of live rock culture on the preexisting quarry environment and ecosystem could be minimal to non-existent. Live Reef Requirements Publicly available information about commercial production of live rock, especially environmental requirements, is sparse. Many if not most of the organisms that colonize live rock inhabit coral reefs. Wheaton et al. (1996) listed 22 animal phyla can be found on coral reefs. It is likely that the physical requirements (Table 1) of living coral reefs would be suitable and desirable for live rock culture. Looe Key Reef data provided by Johns (2015) and Gramer (2015) for salinity and temperature are consistent with the requirements listed in Table 1. Anemones and a broad variety of marine invertebrates host symbiotic algae (Bold and Wynne 1978). Corals contain symbiotic algae called zooxanthellae within their living tissue. The zooxanthellae help provide food and the calcium carbonate needed for the coral polyps to build exoskeletons and grow. The algae also The Quarry Resource Native marine life is already present in the quarry. Live whelks and limpets were attached to the quarry wall. Other native marine species are present in the quarry including coral, trumpet fish and small grouper. This suggests the quarry has or had a direct connection with the Gulf of Mexico or Atlantic Ocean. Larval marine organisms may have been swept into the quarry with seawater entering and exiting through channels or fissures in the limestone. Alternatively the quarry was inundated by ocean water during hurricanes, leaving marine life impounded when storm surges receded. This healthy community of marine organisms suggests that water quality is good for aquaculture. The quarry’s limestone walls and bottom should provide an ample supply of calcium and carbonate to maintain suitable hardness, alkalinity and pH. Salinity was about 37 ppt. Quarry water was clear. Local SCUBA divers reported good visibility to an estimated depth of 10 to 12 m. Rationale for Live Rock/Artificial Reef Culture An article on live rock aquaculture was published in World Aquaculture in 2003 (Falls et al. 2003a). Pieces of limestone or artificial substrate were placed on the ocean floor in Florida coastal waters and native marine organisms colonized the substrate. Many species can be found on live rock including corals, coralline (calcareous) algae, anemones, octocorals, brittle stars, sea urchins and mollusks (Falls et al. 2003b). Cultivation of these rocks (CONTINUED ON PAGE 62) TABLE 1. Physical requirements of coral reefs (adapted from Wheaton et al. 1996). FACTOR REQUIREMENT High light Surface irradiance of 2,000 µE/m2 sec High oxygen concentration 5-7 mg/L Low turbidity 0.01-0.10 mg/L Low nutrient concentration 0.10-1.0 µM (N or P) Stable temperature 23-30 C Stable salinity 33-36 ppt
RkJQdWJsaXNoZXIy MjExNDY=