Development of Goggle Eye (Selar crumenophthalmus) Aquaculture to Service the Florida Sportfishing Industry

Transcription

1 Development of Goggle Eye (Selar crumenophthalmus) Aquaculture to Service the Florida Sportfishing Industry Stieglitz, J., Hoenig, R., and Benetti, D.D Goggle eye (Selar crumenophthalmus), also known as bigeye scad, are a high value marine baitfish used by recreational and commercial fishermen throughout the tropical and subtropical waters of the world. A member of the Carangidae family of fishes, goggle eye are frequently found in large schools, making them vulnerable to predation by apex predators and exploitation by fishermen. In the past, goggle eye were harvested in Florida as a food fish, largely for sale into foreign markets, yet by the mid-1990s stocks had collapsed over large portions of the goggle eye s range, especially in southeast Florida. After the collapse, goggle eye became increasingly valuable to recreational fishermen as one of the most popular and expensive marine baitfish species. While there was some initial aquaculture work done on this species at the University of Hawaii in the 1990 s (Iwai et al., 1996), recent efforts to culture this species in captivity have been centered at the University of Miami Experimental Hatchery (UMEH) on Virginia Key, Florida (Figure 1). Goggle eye research at UMEH has been focused on development of hatchery and grow-out technology for this species. The recreational fishing industry in Florida generates tens of thousands of jobs and an overall annual economic impact of more than $7 billion dollars (Ohs et al., 2013). As part of this industry, the marine baitfish market in Florida, U.S.A. offers an opportunity for the development of commercial aquaculture projects. Given positive aquaculture attributes such as rapid growth, high market price, and demonstrated technical feasibility, goggle eye has been identified as a marine baitfish species potentially suitable for commercial culture. Figure 1. Goggle eye broodstock at UMEH. Broodstock Capture, Handling, and Acclimation The establishment of reliably spawning broodstock is the first step in developing any goggle eye farming operation, since there is currently no commercial entity selling eggs or fingerlings of this species. Adult goggle eye can be obtained off the coast of south Florida using hook and line capture techniques, or purchased from local live bait sellers. Because the goggle eye is a relatively short lived species, one year in the wild and up to three years in captivity (Kawamoto, 1973; Roos et al., 2007), they do not appear to have a robust secondary immune system and are susceptible to secondary infections caused by common commensal bacteria such as Aeromonas hydrophila, Pseudomonas alcaligenes, and 1

2 Plesiomonas shigelloides. These organisms can invade the goggle eye s body at the site of some trauma, even a microscopic one, eventually resulting in septicemia and death (Dan Rothen, D.V.M., University of Miami, Division of Veterinarian Services, personal communication) (Figure 2). Because of this vulnerability to infection, it is extremely important to minimize handling. The standard procedure at UMEH is to administer a light anesthetic and collect broodstock fish individually in plastic bags with water. During collection from the wild it may be necessary to use a soft mesh net. Figure 2. Goggle eye mortality following secondary infection. Upon arriving at the facility, the newly caught wild fish are transferred to a quarantine tank where they are be acclimated to captivity. UMEH protocol is to administer a prophylactic Formalin bath at a dose of 100 ppm for one hour in the quarantine tank. Beginning on the following day after capture, a series of antibiotic baths (Oxytetracycline HCl) are administered over the course of 5 to 10 days at a dose of 50 ppm to mitigate any injuries sustained in collection and transport. Using these methods, it has been possible to regularly catch and acclimate wild goggle eye broodstock to captivity. Due to the sensitive nature of this species, excellent water quality is paramount to holding them for any length of time in captivity. Google eye are a pelagic species that are accustomed to full strength seawater (32 35 ppt) and temperatures ranging from 20 C- 28 C. Temperatures above 30 C can induce stress and prolonged exposure to high temperature typically results in increased mortality. For biosecurity and full control over the culture environment, goggle eye broodstock should be maintained in independent recirculating aquaculture systems (RAS). At UMEH, goggle eye broodstock have been maintained in tanks ranging in volume from 2.5 m 3 up to 80 m 3 using both flow-through and RAS systems to maintain water quality in the tanks (Figure 3). Goggle eye feed well in captivity, eating both inert (pelletized) diets, as well as natural forage items (squid, shrimp, and sardines). Commercially available vitamin supplements may be used to enhance inert and natural diets, but inclusion of such supplements is not imperative for successful broodstock maintenance and spawning. Figure 3. Goggle eye in broodstock tank. 2

3 Spawning Goggle eye broodstock at UMEH spawn volitionally at water temperatures 25 C. Spawning events from healthy broodstock occur regularly in captivity, though hormone induction techniques may also be used to trigger spawning activity. Injections of luteinizing hormone-releasing hormone analogue (LHRHa) at dosages of µg kg -1 or human chorionic gonadotropin (hcg) at a dose of 1000 IU kg -1 have both resulted in successful captive spawning events allowing for collection of viable goggle eye embryos (Figure 4). Goggle eye are gonochoristic serial batch spawners, releasing from 5,000 to over 100,000 eggs per female fish during each spawning event. Year-round spawning of this species in captivity has been achieved at UMEH through water temperature manipulation and consistent maintenance of broodstock nutrition, allowing for year-round fingerling production. by the use of a Formalin or hydrogen peroxide (35% Perox-Aid) bath at a dose of 100 ppm for 1 hour. Goggle eye eggs hatch approximately hours post fertilization depending on water temperature. Following hatching, yolk sac larvae are stocked in larval rearing tanks at a density of larvae per liter where they remain over the course of the entire larval rearing process (Figure 5). Figure 5. Goggle eye yolk sac larvae (12 hrs. post hatch) Figure 4. Goggle eye embryos (18 hrs. post fertilization). Larval rearing Goggle eye fingerlings are produced using modified greenwater culture techniques, whereby live and/or inert algae (Nannochloropsis oculata and Isochrysis galbana) is maintained in the larval rearing tank at densities of 200,000 1,000,000 cells ml -1 during the first days of culture (Figure 6). During this time, water exchange within the culture is kept to a minimum (50 200%) and supplemental aeration and pure oxygen are used to maintain oxygen at or above saturation in the larval rearing tank. Following captive spawning events, UMEH protocol is to sterilize the eggs 3

4 Once mouth gape size allows for ingestion of newly hatched Artemia nauplii (approximately dph), enriched Artemia nauplii are co-fed with the enriched rotifers for 3 5 days. During this time, water exchange rates are increased progressively on each day by approximately 100%, until total exchange rates reach 1000% per day. Figure 6. Larval rearing of goggle eye (greenwater stage). Water temperatures should be maintained between 25 C - 29 C throughout the larval rearing period for proper larval development and survival. Beginning at 2 3 days post hatch (dph), enriched rotifers (Brachionus plicatilis) are introduced into the culture tank at a density of rotifers per ml of culture water. Over the course of the initial days of culture, rotifer concentrations in the tank are maintained at this level. Once rotifers are no longer present in the culture tank and fish are weaned onto Artemia nauplii, a modified clear water pulse feeding larviculture technique is used, as described by Benetti et al. (2008). Figure 8. Goggle eye larvae at 18 dph. Beginning around dph, larvae are weaned onto inert starter diets using similar co-feeding techniques employed in the transition from rotifers to Artemia. By dph the goggle eye are fully weaned onto inert pelletized diets (Figure 9). By 40 dph, the fish are ready to be graded and transferred to larger grow-out tanks. During grow-out, the fish are fed pelletized diets and/or natural forage items. Figure 7. Goggle eye larvae at 10 dph 4

5 rotundiformis, are also advantageous for use in goggle eye larviculture. They are relatively small, measuring as little as 100 µm in width (Hagiwara et al., 2001), they can be enriched to provide critically important HUFA/PUFAs such as DHA, ARA, and EPA (Mourente et al., 1993; Koven et al., 2001), and they have a slow swimming motion that encourages feeding behavior (Dhert, 1996). Because fish larvae must learn to eat new types of live feeds, their initial success in consuming prey is usually relatively low (Houde and Schekter, 1980). Failure to transition from one type of live feed to another is difficult and requires extended periods of co-feeding in order to allow the larvae to adjust. Using these methods, researchers at UMEH have successfully produced numerous batches of goggle eye (Figure 10), including full closure of the goggle eye life cycle whereby first generation (F1) individuals spawned in captivity. Figure 9. Typical goggle eye larval rearing feeding regime (0 35 dph). As with other marine fish, a number of different factors must be considered in order to develop and implement an effective larviculture protocol for goggle eye, including stocking density, live feeds, and microbial control. Goggle eye larvae are relatively small, measuring approximately 2.5 mm with a mouth gape of approximately 180 µm at approximately 3 days post hatch (dph), when their mouth and digestive tract first open (Johnson, 1978). Additionally, all marine fish larvae have relatively short and inefficient digestive tracts with little enzymatic activity and are largely incapable of digesting artificial feeds (Kolkovski, 2001). Given these limitations, calanoid copepods such as Acartia hold great promise as a potential first feed for goggle eye larvae. They are less than 100 µm in diameter during early developmental stages (Schipp, 2006), are highly nutritious relative to other types of live prey items (Evjemo et al., 2003; McKinnon et al., 2003), and their characteristic swimming patterns are highly effective at eliciting strikes from larvae (Schipp, 2006). Preliminary trials looking into the utilization of copepods as a first feed item are being conducted in collaboration with University of Florida s Indian River Research and Education Center (IRREC). Ss-type rotifers, especially B. Figure 10. Fully weaned goggle eye fingerlings (45 dph). Nursery and Grow-out Fully weaned goggle eye fingerlings can be grown out in a variety of tank sizes 5

6 and configurations, with both flowthrough and RAS technologies suitable for this stage of production. Similar to many marine finfish species, goggle eye are carnivorous in nature and consume a wide variety of prey items, including crustaceans and other smaller finfish. Juvenile and adult goggle eye can be grown and maintained on a variety of diets in captivity, including pelletized diets and natural forage (squid, sardines, shrimp, etc.). Due to the natural schooling habits of goggle eye in the wild, this species is able to tolerate fairly high grow-out densities. While a density threshold has not been determined, it is recommended to maintain grow-out densities <15 kg m -3 in land-based tanks due to their susceptibility to secondary infections. Swimming and behavior dynamics of captive goggle eye should also be considered during nursery and grow-out stages. When stressed, goggle eye are extremely rapid swimmers and occasionally strike tank walls when agitated, almost always resulting in death. It has been possible to reduce stress and prevent tank strikes for other fast swimming pelagic species by covering tanks, using gradual light adjustments, and applying stripes to the walls of tanks (Wexler et al., 2003), and many of these techniques have been applied for captive goggle eye culture at UMEH. Water quality is also an important issue. Some small Carangids such as the Florida pompano (Trachinotus carolinus) are relatively sensitive to water quality parameters such as ammonia-nitrogen and nitritenitrogen levels (Weirich and Riche, 2006) and the same may be true for goggle eye. In a study completed by researchers at UMEH, juvenile goggle eye were grown out to the sub-adult stage in 2.5 m 3 fiberglass tanks. Data from this study was used to construct a Von Bertalanffy Growth Model (Figure 11) (Welch et al., 2013). As noted in Figure 11, goggle eye grow rapidly in captivity. Favorable survival rates and food conversion rates, ~90% and <1.5 respectively, were also observed during this study. However, due to the many factors that influence fish growth in captivity, notably water temperature, nutrition, and stocking density, growers may experience growth results that deviate significantly from those represented in Figure 11. Figure 11. Von Bertalanffy Growth Model (solid line) for S. crumenophthalmus (n = 493) with 95% upper and lower confidence intervals using bootstrapped growth parameters (dashed line) for age 1 21 week fish extrapolated to 120 weeks. (From Welch et al., 2013). Nutrition The precise nutritional needs of goggle eye are unclear but do not appear to be dramatically different from other tropical marine species. In nature, goggle eye are largely omnivorous, eating various types of crustaceans and larval and juvenile fish (Roux and Conand, 2000). Through early work with goggle eye at UMEH, 6

7 researchers have been able to wean juvenile and adult goggle eyes onto a variety of different types of feed (Figure 12). aquaculture remain. While wild goggle eye fetch high prices on a per unit basis, as compared to other species of live bait, these prices fluctuate from season to season and year to year depending on a number of market factors. Therefore, farmers considering the culture of goggle eye should be mindful of the multitude of other extrinsic factors which determine commercial success of an aquaculture business, aside from the biological and technical challenges. Acknowledgements Figure 12. Typical pelletized diets used for different life stages of farm-raised goggle eye. Determining optimal nutritional regimes for different life stages of fish is a difficult process because each species has different needs (Izquierdo et al., 2001; Watanabe and Vassallo-Agius, 2003). Research has shown, however, that for all fish providing appropriate levels of various feed components such as lipids (Rainuzzo et al., 1997), n-3 HUFAs (Fernandez-Palacios et al., 1995; Furuita et al., 2002), and carotenoids such as astaxanthin (Watanabe and Vassallo-Agius, 2003), has positive effects on the health of fish. Conclusions Goggle eye aquaculture has been shown to be technically feasible, and this species represents a promising candidate species for marine baitfish culture. However, maintenance and culture of this species in captivity appears to be significantly more challenging than other baitfish species explored for farming in Florida (Ohs et al., 2013). Given these challenges, questions surrounding the economic feasibility of goggle eye This work was funded by a grant by the State of Florida Aquaculture Review Council (ARC) under FDACS Contract No The authors also acknowledge support from the NOAA Saltonstall-Kennedy Program Grant Number NA09NMF for goggle eye research. The authors are indebted to ARC and NOAA for their continued support of the University of Miami Aquaculture Program. References Benetti, D., Sardenberg, B., Welch, A., Hoenig, R., Orhun, M., Zink, I Intensive larval husbandry and fingerling production of cobia Rachycentron canadum. Aquaculture. 281: Dhert, P Rotifers. In: Manual on the production and use of live food for aquaculture, Eds: Lavens, P. and Sorgeloos, P. FAO Fisheries Technical Paper 361. Ghent, Belgium. ISBN Evjemo, J., Reitan, K., Olsen, Y Copepods as live food organisms in the larval rearing of halibut larvae (Hippoglossus hippoglossus L.) with special emphasis on the nutritional value. 7

8 Fernandez-Palacios, H., Izquierdo, M., Robaina, L., Valencia, A., Salhi, M., Vergara, J Effect of n-3 HUFA level in broodstock diets on egg quality of gilthead sea bream (Sparus aurata L.). Aquaculture. 132(3-4): Furuita, H., Tanaka, H., Yamamoto, T., Suzuki, N., Takeuchi, T Effects of high levels of n-3 HUFA in broodstock diet on egg quality and egg fatty acid composition of Japanese flounder, Paralichthys olivaceus. Aquaculture. 210(1-4): Hagiwara, A., Gallardo, W., Assavaaree, M., Kotani, T., Araujo, A Live food production in Japan: recent progress and future aspects. Aquaculture. 200(1-2): Houde E., and Schekter, R Feeding by marine fish larvae: developmental and functional responses. Environmental Biology of Fishes. 5(4): Iwai, T., Tamaru, C., Yasukochi, L., Alexander, S., Yoshimura, R., Mitsuyasu, M., Natural Spawning of Captive Bigeye Scad Selar crumenophthalmus in Hawaii. Journal of the World Aquaculture Society. 27(3). Izquierdo, M., Fernandez-Palacios, H., Tacon, A Effect of broodstock nutrition on reproductive performance of fish. Aquaculture. 197(1-4): Johnson, G Development of fishes of the Mid-Atlantic Bight. An atlas of egg, larval and juvenile stages. Vol. 4. Carangidae through Ephippidae. US Fish Wildl. Serv. Biol. Serv. Prog. FWS OBS-78/12. Kawamoto, P Management investigation of the akule or bigeye scad (Trachurops crumenophthalmus) (Bloch). Hawaii Division of Fish and Game, Project Report No. H-4-r, Honolulu, Hawaii. Kolkovski, S Digestive enzymes in fish larvae and juveniles implications and applications to formulated diets. Aquaculture. 200: Koven, W., Barr, Y., Lutzky, S., Ben-Atia, I., Weiss, R., Harel, M., Behrens, P., Tandler, A The effect of dietary arachidonic acid (20:4n 6) on growth, survival and resistance to handling stress in gilthead seabream (Sparus aurata). Aquaculture. 193: McKinnon, A., Duggan, S., Nichols, P., Rimmer, M., Semmens, G., Robino, B The potential of tropical paracalanid copepods as live feeds in aquaculture. Aquaculture. 223: Mourente G., Rodriguez, A., Tocher, D., Sargent, J Effects of dietary docosahexanenoic acid (DHA; 22:6n-3) on lipid and fatty acid compositions and growth in gilthead seabream (Sparus aurata L.) larvae during first feeding. Ohs, C.L., Creswell, R.L., and DiMaggio, M.A Growing marine baitfish: A guide to Florida s common marine baitfish and their potential for aquaculture. University of Florida/IFAS. Florida SeaGrant Publication. February Rainuzzo, J., Reitan, K., Olsen, Y The significance of lipids at early stages of marine fish: a review. Aquaculture. 155(1-4): Roos, D., Roux, Ol, Conand, F Notes on the biology of the bigeye scad, Selar crumenophthalmus (Carangidae) around Reunion Island, southwest Indian Ocean. Scienta Marina. 71(1): Roux, O. and Conand, F Feeding Habits of the Bigeye Scad, Selar crumenophthalmus (Carangidae) in La Reunion Island Waters (South-Western Indian Ocean). Cybium, 24(2): Schipp, G The Use of Calanoid Copepods in Semi-Intensive, Tropical Marine Fish Larviculture. En: Editors: Suarez, L. Marie, D., Salazar, M., Lopez, M., Cavazos, D., Cruz, A., Ortega, P. Avances en Nutricion Acuicola VIII. VIII Simposium Internacional de Nutricion Acuicola Noviembre. Universidad Autonoma de Nuevo Leon, Monterrey, Nuevo Leon, Mexico. ISBN

9 Watanabe, T., and Vassallo-Agius, R Broodstock nutrition research on marine finfish in Japan. Aquaculture. 227(1-4): Weirich, C. and Riche, M Acute tolerance of juvenile Florida pompano, Trachinotus carolinus L., to ammonia and nitrite at various salinities. Journal of Aquaculture Research. 37: Welch, A., Hoenig, R., Stieglitz, J., Daugherty, Z., Sardenberg, B., Miralao, S., Farkas, D., Benetti, D Growth rates of larval and juvenile bigeye scad Selar crumenophthalmus in captivity. SpringerPlus :634. Wexler, J., Scholey, V., Olson, R., Margulies, D., Nakazawa, A., Suter, J Tank culture of yellowfin tuna, Thunnus albacares: developing a spawning population for research purposes. Aquaculture. 220: