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The lack of data on the age, growth, and reproduction of the Atlantic Goliath Grouper Epinephelus itajara off the coasts of Florida (USA) makes it difficult to estimate the extent of their population recovery following the 1990 fishery closure, as well as the potential effects of the recent (2023) opening of a fishery for juveniles. Goliath Grouper from the Atlantic coast of Florida were non-lethally sampled for size (total length, TL), age (via fin rays), and sex and reproductive stage (via gonad biopsies, milt/egg expression, gonopores) from May to October 2010–2016. Of 653 unique fish captured (not including 118 recaptures), 257 (39.4%) were females (122–228 cm TL; 5–20 years old), 264 (40.0%) were males (104–225 cm TL; 4–22 years old), 100 (15.3%) were unsexed (82–211 cm TL; 3–15 years old), and 32 (4.9%) were protogynous hermaphrodites (108–209 cm TL; 5–20 years old). Protogyny was conclusively determined in two fish recaptured and re-biopsied that had transitioned from female to male. However, an overlap in the age and size of males and females, a 1:1 sex ratio, and the presence of relatively small, young, mature males, in combination with an apparently low functional sex change rate, all indicated that the sexual pattern of Goliath Grouper was functionally gonochoristic with the potential for diandric protogyny. Females > 10 years old were larger-at-age than males, and Goliath Grouper from the Atlantic coast were larger-at-age than fish from the Gulf of Mexico. These differences in age, growth, and reproductive strategy—as well as the nascent fishery for juveniles—need to be monitored closely so that the current and future reproductive capacity of the population continues to ensure growth and sustainability. [ABSTRACT FROM AUTHOR]

Atlantic goliath grouper (Epinephelus itajara), the largest reef fish in the Western Atlantic, exhibit high site fidelity to home reefs but also undertake annual migrations to distant spawning sites. Once relatively common throughout Florida and the Caribbean, the species; is now considered vulnerable (i.e., threatened with extinction) due to overfishing and loss of juvenile mangrove habitat. Goliath grouper in the southeastern US form annual spawning aggregations on high-relief reefs located offshore of both the Gulf and Atlantic coasts of Florida, US. To determine spawning site fidelity and describe migration patterns to aggregations, we implanted 50 adult goliath grouper with acoustic transmitter tags from 2010 to 2013. Fish were tagged at known spawning sites off the Florida Atlantic coast and tracked as they moved through the FACT Network array of acoustic receivers. From 2010 to 2020, we collected ~7 million detections from tagged goliath grouper at 153 sites along the southeastern US Atlantic coast. Results of this long-term tracking indicate that adult goliath grouper are relatively sedentary during non-spawning months (Nov to June) but move significantly more prior to, during, and immediately after spawning (July to Oct). Inter-annual spawning site fidelity was high: between 80–93% of tagged fish returned to the same spawning sites each year. Arrival timing at spawning sites coincided with the August new moon, with males arriving earlier than females. Some individuals migrated distances greater than 400-km per year, with observed migration rates of up to 44-km per day prior to spawning. Long-term tagging data are critical for understanding movement patterns and developing management strategies for this species of special conservation concern. [ABSTRACT FROM AUTHOR]

The Atlantic Goliath Grouper Epinephelus itajara (Lichtenstein, 1822) occurs on both sides of the Atlantic, from the Carolinas (USA) to Brazil in the western Atlantic and historically from North Senegal to North Angola off of West Africa in the eastern Atlantic. While there are relatively good data on their distribution in the western Atlantic, confirmed occurrences, population status, fishing reports, and trade data are almost non-existent for West Africa. Part of the problem is that tropical West African countries largely lack the wherewithal to fund the research needed to evaluate this species, nor do they have laws, management plans, or viable enforcement measures that might lead to effective population recovery or protection for essential juvenile mangrove habitats. Given the lack of published studies on this species in West Africa, the primary objectives of this paper are (1) to describe all known historical and current anecdotal information available on this species and (2) to encourage the increased monitoring of habitats where viable populations might still occur (i.e., mangroves, oil rigs, and oil platforms). [ABSTRACT FROM AUTHOR]

Atlantic Goliath Grouper, Epinephelus itajara, the largest grouper in the western North Atlantic, exhibits life history characteristics (e.g., it is slow-growing, long-lived, and late-maturing) that make it particularly susceptible to fishing pressure. Otoliths, the structure typically processed for age determination, are usually collected as part of fishery monitoring, but otoliths are not available from Goliath Grouper due to a harvest moratorium enacted in 1990 for United States waters. Alternative structures—such as dorsal fin rays or spines—can be acquired for ageing via nonlethal sampling and may provide reliable age estimates. Since 2006, the Florida Fish and Wildlife Conservation Commission (FWC) has been collecting incidental Goliath Grouper samples from mortality events including those from cold kills and red tides. Corresponding otolith, dorsal fin ray and dorsal fin spine samples were compared to determine the accuracy and precision of the external ageing structures. Marginal increment analyses indicated that annulus (translucent zone) deposition occurred primarily in March–June on spines and in April–June on rays. While ages determined from both rays and spines exhibited high precision, the accuracy compared to otolith ages was low as a result of systematic underageing of both external structures, particularly at the oldest age classes. A correction factor was applied to rays and spines that remedied the underageing, but the correction factor was more successful for spines. An analysis of ray and spine section accuracy based on nonlethal structure removal from the fish (i.e., comparing ages from sections at the base of the structure within the body to those sectioned from the external surface of the body) determined that spines can be accurately aged when sampled distal of the base of the structure, but that rays cannot. Nonlethal sampling and ageing of Goliath Grouper spines facilitated by public participation could address management goals and help determine the offshore population age structure. Simultaneously, it could contribute critical data needed for a traditional stock assessment, should such a path be warranted by the recovery or management of the species. [ABSTRACT FROM AUTHOR]

Here, the authors investigate the evolution of scientific literature on the Atlantic goliath grouper (Epinephelus itajara), the largest grouper species in the Atlantic. This species was considered threatened according to the IUCN for nearly three decades due to overfishing and has been protected from fishing in a large part of its range. For the purpose of evaluating the scientific production on an endangered species banned from fishing, the authors present a scientometry and synthesis review analysing the literature produced in the timeline and the content of their studies. To this end, they set up an almost 60‐year literary database through the Scopus, Web of Science and Google Scholar platforms. They analyse the publication and knowledge area patterns over the time in the world and in Brazil. They also feature the main areas, locations, ecosystems and types of those research studies and briefly describe the main records found in each decade. An increase in the number of publications was observed from the 1990s onwards worldwide, and particularly in Brazil from the 2000s, coinciding with the pioneering legislations for species protection. Most of the studies were classified within ecology and conservation and took place in countries that implemented moratoriums and had extensive areas of mangroves. Thus, fishing moratorium, classification as endangered, mangroves distribution and conservation all play a role in the studies distribution and contribute positively to the knowledge, as well as support conservation strategies for the species and its ecosystems of occurrence. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Orofacial Pain is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to reveal the first report of the natural spawning of F1 hybrid grouper (TGGG), a crossbreed between the tiger grouper, Epinephelus fuscoguttatus × giant grouper, E. lanceolatus, since its first production in 2006. This marks the completion of its full cycle after a 10-year period. In order to establish a seed rearing protocol for a novel F2 hybrid TGGG, natural spawning, embryonic and larval developments were thoroughly observed. Five batches of natural spawning were recorded with an average of 1.50-15.3 kg eggs collected, while fertilization and hatching rates were recorded at 85.3-97.6%, and 63.0-98.3%, respectively. F2 larvae hatched out at 17:50 hours with an average body size of 1.74 ± 0.01 mm, and a yolk sac volume of 0.85 ± 0.197 mm3. The first feeding was initiated 3 days after hatching, which coincided with the onset of functional feeding apparatus and active swimming behavior. Larval dorsal and pelvic spines were formed at 6 days AH coupled with dynamic feeding activity, as more food was found in the digestive tract. Meanwhile, the F2 hybrid grouper shifted habitat from pelagic to benthic as early as 25 days AH, and entered a juvenile stage at 35 days AH, attaining a skin coloration similar to that of the F1 juvenile. This study concluded that naturally spawned eggs of F2 hybrid TGGG were exceptionally high in quality, although larvae were small and fragile, and performed vigorous feeding activities and cannibalistic behavior. Thus, these findings can serve as primary data to further develop the optimal rearing protocol to enhance the overall rearing performance. [ABSTRACT FROM AUTHOR]

Protected areas not allowing extractive activities (here called fully protected area) are a spatially explicit conservation management tool commonly used to ensure populations persistence. This is achieved when an adequate fraction of a species' population spends most of its time within the boundaries of the protected area. Within a marine context, home ranges represent a tractable metric to provide guidance and evaluation of fully protected areas. We compiled peer-reviewed literature specific to the home ranges of finfishes and invertebrates of ecological and/or commercial importance in the Mediterranean Sea, and related this to the size of 184 Mediterranean fully protected areas. We also investigated the influence of fully protected areas size on fish density in contrast to fished areas with respect to home ranges. Home range estimations were available for 11 species (10 fishes and 1 lobster). The European spiny lobster Palinurus elephas had the smallest home range (0.0039 ± 0.0014 km 2 ; mean ± 1 SE), while the painted comber Serranus scriba (1.1075 ± 0.2040 km 2 ) had the largest. Approximately 25% of Mediterranean fully protected areas are larger than 2 times the size of the largest home range recorded. Fish densities were significantly higher when fully protected areas were larger than the home range, while no change in density occurred when home ranges were larger than fully protected areas. These results display a direct link between the effectiveness of fully protected areas and species' home range, suggesting that fully protected areas of at least 3.6 km 2 may increase the density of local populations of these coastal marine species. [ABSTRACT FROM AUTHOR]

Hybridization was used to take advantage of desirable traits in offspring. In the present study, we applied the cryopreserved Epinephelus lanceolatus sperm into interspecific hybridization with E. moara. Successful hybridization between these two species was achieved and cultured in 23-24°C seawater (34%). There was no difference in survival rate between hybrid (E. moara ♀ × E. lanceolatus ♂) and non-hybrid (E. moara ♀ × E. moara ♂) at 24 hrs post hatch (HPH), but less hybrid (14.35 ± 8.02%) hatched than non-hybrid (93.60 ± 1.65%), which might be due to irregularity cell cleavage and skeletal deformities from the formation of embryonic body to the later embryonic development. Similar phenomenon was found in hybrid embryos from fertilization with fresh sperm, indicating that species variations between parents, rather than cryopreserved sperm, resulted in deformities in embryos. Mean hatch time of the hybrid was 1 hr faster than that of E. moara. The hybrid was 1.95 ± 0.06 mm in total length when newly hatched and reached 38.00 mm at 58 days post hatch (DPH), which showed faster growth than E. moara (recorded in the previous study). Considering its faster growth, E. moara × E. lanceolatus hybrid was a potential breeding production in aquaculture. Over 212,000,000 larvae have been produced and launched in the market since 2015. The results of this study also shed some lights on further comparative studies in grouper hybrid performance. [ABSTRACT FROM AUTHOR]

Abstract: We tested whether fishers’ local ecological knowledge (LEK) of two fish life‐history parameters, size at maturity (SAM) at maximum body size (MS), was comparable to scientific estimates (SEK) of the same parameters, and whether LEK influenced fishers’ perceptions of sustainability. Local ecological knowledge was documented for 82 fishers from a small‐scale fishery in Samaná Bay, Dominican Republic, whereas SEK was compiled from the scientific literature. Size at maturity estimates derived from LEK and SEK overlapped for most of the 15 commonly harvested species (10 of 15). In contrast, fishers’ maximum size estimates were usually lower than (eight species), or overlapped with (five species) scientific estimates. Fishers’ size‐based estimates of catch composition indicate greater potential for overfishing than estimates based on SEK. Fishers’ estimates of size at capture relative to size at maturity suggest routine inclusion of juveniles in the catch (9 of 15 species), and fishers’ estimates suggest that harvested fish are substantially smaller than maximum body size for most species (11 of 15 species). Scientific estimates also suggest that harvested fish are generally smaller than maximum body size (13 of 15), but suggest that the catch is dominated by adults for most species (9 of 15 species), and that juveniles are present in the catch for fewer species (6 of 15). Most Samaná fishers characterized the current state of their fishery as poor (73%) and as having changed for the worse over the past 20 yr (60%). Fishers stated that concern about overfishing, catching small fish, and catching immature fish contributed to these perceptions, indicating a possible influence of catch‐size composition on their perceptions. Future work should test this link more explicitly because we found no evidence that the minority of fishers with more positive perceptions of their fishery reported systematically different estimates of catch‐size composition than those with the more negative majority view. Although fishers’ and scientific estimates of size at maturity and maximum size parameters sometimes differed, the fact that fishers make routine quantitative assessments of maturity and body size suggests potential for future collaborative monitoring efforts to generate estimates usable by scientists and meaningful to fishers. [ABSTRACT FROM AUTHOR]

Viral nervous necrosis caused by nervous necrosis virus (NNV) is one of the most severe diseases resulting in high fish mortality rates and high economic losses in the giant grouper industry. Various NNV vaccines have been evaluated, such as inactivated viruses, virus-like particles (VLPs), recombinant coat proteins, synthetic peptides of coat proteins, and DNA vaccines. However, a cheaper manufacturing process and effective protection of NNV vaccines for commercial application are yet to be established. Hence, the present study developed a novel subunit vaccine composed of a carrier protein, receptor-binding domain of Pseudomonas exotoxin A, and tandem-repeated NNV coat protein epitopes by using the structural basis of epitope prediction and the linear array epitope (LAE) technique. On the basis of the crystal structure of the NNV coat protein, the epitope was predicted from the putative target cell receptor-binding region to elicit neutralizing immune responses. The safety of the LAE vaccine was evaluated, and all vaccinated fish survived without any physiological changes. The coat protein-specific antibody titers in the vaccinated fish increased after vaccine administration and exerted NNV-neutralizing effects. The efficacy tests revealed that the relative percent survival (RPS) of LAE antigen formulated with adjuvant was above 72% and LAE vaccine was effective for preventing NNV infection in giant grouper. This study is the first to develop an NNV vaccine by using epitope repeats, which provided effective protection to giant grouper against virus infection. The LAE construct can be used as a vaccine design platform against various pathogenic diseases. [ABSTRACT FROM AUTHOR]

This study investigated the effects of low salinity on growth, survival, and stress response in longtooth grouper, Epinephelus bruneus, and the hybrid grouper resulting from crossing E. bruneus females and E. lanceolatus males. There were no significant differences in the hybrids for any of the above growth values among different salinity groups, however the percent weight gain was significantly lower in the 8 Practical Salinity Unit (psu) group than in the other salinity groups. As for survival, only longtooth grouper in the group reared at 8 psu died. The plasma cortisol levels tended to increase at lower salinities in both the longtooth grouper and the hybrids. Plasma Na+, K+, Cl- concentrations in the hybrid were not significantly different among the salinity groups, while Na+ and Cl- concentrations in the longtooth grouper were significantly lower in the 8 psu group than in the other treatments. The above results indicate that both the longtooth grouper and the hybrid grouper juveniles were highly adaptable to variations in salinity. The optimal salinity for rearing longtooth grouper was found to be 24 psu, while the hybrids had a larger tolerance range of 16-32 psu. Results therefore showed that the hybrid grouper has a higher tolerance than the longtooth grouper for low salinity. [ABSTRACT FROM AUTHOR]

We evaluated Atlantic Goliath Groupers, Epinephelus itajara, in their nursery habitats via microchemical analyses of fin rays. Juveniles were sampled from known nursery habitats off southwest Florida, and adults were primarily sampled from a spawning aggregation off southeast, Florida. We collected fin rays using a non-lethal technique that is minimally invasive with no known negative effects on growth or survival. Trace metal constituents in the fin rays were quantified with an inductively coupled plasma mass spectrometer via laser ablation (LA-ICP-MS). Two spatial scales were quantified to test the limitations of grouping individuals based on elemental compositions. On a small spatial scale (i.e., 100s of m), individuals were correctly classified within individual watersheds 64% of the time. On a larger spatial scale (i.e., 10s-100s of km), juveniles were classified with 100% accuracy. Trace metals in adults were analyzed by back-tracking across fin ray annuli to a year in which our previous studies have shown these adults occupied their juvenile habitats (i.e., 2006). These fish were grouped using a measure of dissimilarity and then analyzed to test whether we could reclassify them into these same groupings based solely on the chemical components in their fin rays, which was done with over 84% accuracy. Although juvenile habitats of the adults could not be determined due to the lack of baseline data, classifications were driven by similar elements to those that drove the classification of juveniles, suggesting similar physiological mechanisms. The results highlight the importance of spatial scale for interpreting microchemical analyses on calcified structures in fishes. [ABSTRACT FROM AUTHOR]

The diel, lunar, and seasonal timing of spawning in Atlantic goliath grouper Epinephelus itajara (Lichtenstein, 1822) in the United States is highly specific, occurring at night during new moon phases of August, September, and October. We derive these patterns from four lines of evidence apparent on spawning sites during the known spawning season: (1) from the transitory appearance of fish aggregations; (2) from simultaneous recordings of goliath grouper nighttime calls and nighttime vertical ascents that were far more frequent during the new moon phase than on the full moon; (3) from collections of goliath grouper eggs (genetically verified) at night downstream from known spawning sites; and (4) from significantly higher frequencies of both hydrated oocytes (indicating imminent spawning) and postovulatory follicles (indicating recent spawning) in ovarian biopsies taken from goliath grouper captured on spawning sites during new moon phases relative to full moon phases. We suggest that dark-night spawning is an adaptation minimizing egg predation by several species of scad [Decapterus punctatus (Cuvier, 1829), Decapterus tabl Berry, 1968, and Decapterus macarellus (Cuvier, 1833)] and herring [Sardinella aurita Valenciennes, 1847 and Etrumeus teres (DeKay, 1842)] that are abundant on goliath grouper spawning sites. The seasonal spawning of goliath grouper, late summer-early fall, coincides with habitat conditions considered ideal for settlement of early juveniles in mangrove nurseries. [ABSTRACT FROM AUTHOR]

Goliath grouper Epinephelus itajara suffered significant overfishing in the United States until they were protected from harvest in 1990. As the population recovers, interactions between Goliath grouper and anglers have increased, and are often reported to management agencies as complaints after grouper predation upon hooked fish. Goliath grouper are generally characterized as opportunistic predators capable of consuming a wide variety of prey types; however, minimal data are available regarding the prey capture behavior of this species. Kinematic analyses of adult Goliath grouper feeding events demonstrated the capacity of individuals to modulate feeding behavior based upon the mobility and position of 'prey' items. Mobile epibenthic food (tethered swimming fish) elicited larger maximum gapes, faster times to food capture, shorter times to mouth closing, and more rapid total bite durations than food items that were not moving (cut dead bait). Feeding sequences involving mobile food items were characterized by a significantly higher degree of ram feeding behavior, while immobile food elicited primarily suction feeding and were preceded by a slower and closer approach to the food item prior to the onset of mouth opening. The findings are discussed in light of predation upon angled species and demonstrate the ability of Goliath grouper to adjust their feeding strategy based upon prey type and condition. This behavior likely allows for the exploitation of a wide variety of prey and provides an expansive dietary breadth for these opportunistic predators. [ABSTRACT FROM AUTHOR]

The Goliath grouper ( Epinephelus itajara ) is one of the most endangered species of fish of the subfamily Epinephelinae. Slow to develop and mature, and dependent on mangrove habitats for breeding, the species also suffers intense harvesting, which has reduced drastically in numbers in many areas. To contribute to the understanding of the characteristics of E. itajara populations, we conducted a molecular genetics study of the species, focusing on populations from the Northern Brazilian coast. The mtDNA control region (D-loop) of 116 individuals from five localities (Bragança, Ajuruteua, Parnaíba, Fortaleza and Natal) was analysed, and a sequence of 499 base pairs identified. Analyses of the sequences indicated that genetic variability was generally lower in E. itajara than in other endangered species of the genus. AMOVA found no significant grouping structure among the populations. Nested Clade Analysis revealed a significant association between genetic variability and geographic distribution among only three populations (Ajuruteua, Parnaíba and Natal). Genetic diversity was higher in populations from the Amazon region, which may be related to the better conservation of mangrove habitats in this area. Therefore, the present study could be used for the implementation of conservation and management measures in order to protect and consolidate these populations.

Investigamos aspectos gerais do Conhecimento Ecológico Local (CEL) depescadores de espinhel e pesca subaquática sobre sete espécies de peixes marinhos da família Serranidae (habitat de ocorrência, tamanho máximo e denominação popular) e as principais alterações percebidas no ambiente marinho na Baía Babitonga, Estado de Santa Catarina,Brasil. Em termos gerais, o CEL sobre os peixes corrobora a literatura em ictiologia, trazendo informações originais em escala local. Pescadores de comunidades vizinhas e/ou praticantes de diferentes artes de pesca podem desenvolver denominações e um corpo deCEL diferenciado sobre os recursos pesqueiros de uma mesma área. Verificamos que a legislação que institui a moratória da pesca de Epinephelus itajara desconsidera as denominações locais da espécie, impossibilitando a sua interpretação pelos pescadores locais e gerando conflitos na aplicação da lei. As principais alterações ambientais registradas foram: diminuição da abundância dos recursos pesqueiros em geral (especialmente do Parambijú Rachycentron canadum), e os efeitos da interrupção antrópica do “Canal do Linguado” na hidrologia e sedimentologia da Baía Babitonga (assoreamento e aumento da turbidez da água).General aspects of the Local Ecological Knowledge (LEK) of long-line and spear fishermen on seven fish species of the Serranidae family (habitat use, maximum size and popular names) and on the main marine environmental changes were investigated in Babitonga Bay, Santa Catarina State, Brazil. In general, LEK on fishes corroborates theichthyology literature, bringing original information in a local scale. Neighbor fishermen communities can develop different local species nomenclature and different LEK for fishery resources at the same area. We have verified that the fishing ban legislation on Epinephelus itajara in Brazil does not consider local species denominations, turning impossible its interpretation by local fishermen and generating conflicts on the law’s applicability. Themain environmental changes registered were: decreasing abundance of fishery resources in general (and in particular that of the “Parambijú” (Cobia) Rachycentron canadum), and the effects of the anthropogenic interruption of the “Linguado Channel” on the hydrological and sedimentological characteristics of the Babitonga Bay (channel-bed shallowing and increased water turbidity).

Giant groupers ( Epinephelus lanceolatus ), an important aquaculture fish in Asia, are attacked by nervous necrosis virus (NNV), belonging to betanodavirus. Environmental salinity can affect fish immunity and physiology. We examined whether decreasing salinity from 30 to 15 ppt during acclimation of groupers could affect survival with NNV infection and the associated factors. Although NNV infection decreased muscle moisture, up-regulated the gene expression of Na + -K + -2Cl − cotransporter isoform 2, and elevated plasma cortisol level in groupers, these factors were not related to the higher mortality of groupers reared at 30-ppt salinity (S30-groupers), compared to 15-ppt reared groupers (S15-groupers). Infected S30-groupers exhibited high leukocyte count and innate immune gene expression level. Moreover, NNV-infected dead S30-groupers showed high IL-1β gene expression level but low NNV load in the brain. The high or excess IL-1β gene expression levels in the brain of NNV-infected S30-groupers may be the factor in high mortality. [ABSTRACT FROM AUTHOR]

The article discusses a study which described the occurrence of Atlantic goliath grouper Epinephelus itajara aggregations along the coasts of Brazil using data from literature, fishermen's catches and drivers' sightings. Topics include the goliath grouper's behavior during the reproductive season, a total of 98 reports of goliath grouper aggregations that were described at several sites and the overall abundance reported.

Recently, fisheries managers have been faced with high uncertainty about Atlantic goliath grouper ( Epinephelus itajara ) stock status, especially due to the lack of fishery-dependent data since the harvest moratorium in 1990. Regardless of this uncertainty, the angling community has been pressuring fishery managers to open the goliath grouper to recreational take, while the diving community has been pressuring managers to keep the fishery closed due to the touted ecotourism value of the spawning aggregations. A previous study estimated that resident anglers in Florida who wanted the fishery open were willing to pay between US$34 and US$79 to harvest a goliath grouper. Using a survey instrument with choice experiments, the present study estimated that divers ( n = 1537) off eastern Florida would be willing to pay approximately US$103 for a dive trip with one goliath grouper encounter during the months of their spawning aggregation (August–October), and US$202 if there are 40 goliath grouper (such as is common on a many spawning aggregation sites). Results suggested that divers coming from outside of Florida were willing to pay higher rates for dive trips with goliath grouper encounters; and at spawning aggregations sites, willingness to pay was estimated around US$336 for these non-Florida divers. Based on life-history traits of goliath grouper and the high value of their spawning aggregation sites, we suggest any changes in goliath grouper policy that would negatively impact spawning aggregation numbers be made with caution. [ABSTRACT FROM AUTHOR]

The Atlantic goliath grouper, Epinephelus itajara, is a critically endangered species, threatened by illegal fishing and the destruction of its habitats. A number of other closely related grouper species found in the western Atlantic are also fished intensively. While some countries apply rigorous legislation, illegal harvesting followed by the falsification of fish products, which impedes the correct identification of the species, is a common practice, allowing the catch to be marketed as a different grouper species. In this case, molecular techniques represent an important tool for the monitoring and regulation of fishery practices, and are essential for the forensic identification of a number of different species. In the present study, species-specific primers were developed for the Cytochrome Oxidase subunit I gene, which were applied in a multiplex PCR for the simultaneous identification of nine different species of Epinephelidae: Epinephelus itajara, E. quinquefasciatus, E. morio, Hyporthodus flavolimbatus, H. niveatus, Mycteroperca acutirostris, M. bonaci, M. marginata, and M. microlepis. Multiplex PCR is a rapid, reliable and cost-effective procedure for the identification of commercially-valuable endangered fish species, and may represent a valuable tool for the regulation and sustainable management of fishery resources. [ABSTRACT FROM AUTHOR]

In this study, seasonal numerical abundance of the critically endangered Atlantic goliath grouper Epinephelus itajara was estimated by conducting scuba dive surveys and calculating sightings-per-unit-effort ( SPUE) at three sites in southern Brazil. Seasonal differences in size and reproductive condition of captured or confiscated specimens were compared. The SPUE differed significantly with season, increasing in late spring and peaking during the austral summer months. A significant effect was observed in the number of fish relative to the lunar cycle. All females sampled during the summer were spawning capable, while all those sampled during other seasons were either regressing or regenerating. What these data strongly infer is that the E. itajara spawning aggregation sites have been located in the southern state of Paraná and the northern state of Santa Catarina and summer is the most likely spawning season. Size frequency distributions, abundance and reproductive state were estimated and correlated with environmental variables. [ABSTRACT FROM AUTHOR]

Comber is an important bycatch species in the trawl fishery both in the Mediterranean and the Atlantic. Age and growth studies have been restricted to the eastern Mediterranean and no methodologies were ever applied to ensure accuracy and precision. In this study a total of 471 otoliths from specimens ranging from 12 to 26 cm were used. Precision indices showed a high level of agreement between readers and no evidence of systematic disagreement was obtained. To estimate fish growth and due to the absence of individuals smaller than 12 cm, three approaches were used to estimate the von Bertalanffy growth parameters: whole otolith readings, back calculation and a combination of both methodologies. Akaike’s information criterion suggests that the back calculation approach was the best one for describing comber growth: TL = 25.26 [1−e(−0.21(t+1.72)]. Natural mortality estimates varied betweenM = 0.44 year−1andM = 0.48 year−1while estimates of the fishing mortality varied between 0.12 year−1and 0.16 year−1and the exploitation rate between 0.20 and 0.27. [ABSTRACT FROM AUTHOR]

The giant grouper ( Epinephelus lanceolatus) is a coral fish with high commercial value in Southeast Asia. In the present study, we isolated 11 microsatellite DNA markers, and analysed the genetic diversity and differentiation between cultured stocks and wild populations of the giant grouper originating from the South China Sea. A total of 390 alleles at 11 microsatellite loci were detected in 130 individuals from five different populations. The expected heterozygosity varied from 0.131 to 0.855 with a mean value of 0.623 and the observed heterozygosity varied from 0.145 to 0.869 with a mean value of 0.379. The allelic richness and heterozygosity studies revealed that the genetic diversity of the cultured population was significantly reduced when compared with that of the wild population. The F , pairwise F values, analysis of molecular variance (AMOVA), three-dimensional factorial correspondence analysis and structure analysis revealed significant population differentiation between the cultured stocks and the wild populations, among the three cultured populations and between the two wild populations. These differences may be caused by random genetic drift, the effects of artificial selection and founder effects. Our results will be useful in the management of cultured stocks and conservation of wild populations of the giant grouper. [ABSTRACT FROM AUTHOR]

Parental contributions of giant grouper to communal spawns in captivity are important for establishing genetic management of the species. In this study, we have followed the spawning dynamics of three males and three females over six to eight consecutive days, over three time periods. Polymorphic microsatellite markers were validated and utilised to successfully determine parentage in 574 offspring from 20 nights of spawns. Variation of both maternal and paternal contributions between nights in batches of spawns was significant (P < 0.001). Most paternal assignments were attributed to one dominant male who initiated each spawning batch, however, all males and females successfully mated over the spawning period. There was a significant (P < 0.01) trend towards a polygamous reproductive mode for giant grouper: in two of the three batches of spawns, where on some nights, eggs from all females were fertilised by multiple males. Genetic variation was assessed between parents and offspring. There was a loss of alleles on each spawning night, however, if offspring from a series of consecutive nights were combined, most or all of the genetic variation would be maintained in the F 1 generation. This research validates the use of molecular tools for genetic monitoring of giant grouper and improves the understanding of spawning dynamics of protogynous hermaphroditic communal spawners over time in an aquaculture setting. Statement of relevance The finding of this study shows that the dominant giant grouper male initiates spawning and is the primary contributor however other males contribute to spawns. This contributes to our understanding of grouper spawning behaviour, and offers important information to grouper growers with respect to the need to collect eggs over consecutive days to ensure that the full genetic diversity is captured. [ABSTRACT FROM AUTHOR]

The present study established and confirmed an efficient technology for groupers: giant grouper Epinephelus lanceolatus , orange-spotted grouper E. coioides , seven-band grouper, E. septemfasciatus , and kelp grouper E. moara sperm cryopreservation and successfully applied the cryopreserved E. lanceolatus sperm into interspecific hybridization with E. coioides . For both E. lanceolatus and E. coioides, the best motility of postthaw sperm were achieved using 6% to 10% DMSO, 6% to 16% propylene glycol, and 6% ethylene glycol as cryoprotectants. Furthermore, we have successfully applied this method into the other two species of E. septemfasciatus (74.56 ± 5.45%) and E. moara (71.67 ± 5.10%) sperm cryopreservation and obtained high motility, respectively. Computer-assisted sperm motion analysis showed that the postthaw sperm of the four species of grouper could keep 30 to 35 minutes motile state in nature seawater. And the freezing–thawing process decreased the sperm motility, speed, and longevity but did not significantly change the sperm movement pattern, and the progressive linear motion still was the dominant movement pattern. For the four species of grouper, the ultrastructural analysis showed 70% to 80% of the spermatozoa had intact morphology with a little of swelling; 20% to 30% were damaged, such as swelling or rupture of head, midpiece, and tail region; and 10% to 20% were severely damaged. Whereas, by the microscopic observation, more than 90% of the postthaw sperm presented normal morphology. In the artificial insemination and hybridization experiment, high fertilization rates and hatching rates were achieved when using 10% DMSO (88.7 ± 5.3%, 85.3 ± 7.4%) and 10% propylene glycol (86.8 ± 3.3%, 83.1 ± 6.6%), with no significant difference in comparison with control (92.2 ± 1.4%, 87.9 ± 4.2%). In addition, we found the embryos from postthaw sperm of E. lanceolatus and E. coioides eggs developed and grew normally as reported in previous study on hybridization of groupers ( E. coioides × E. lanceolatus ) using cryopreserved sperm. The results of the present study further validated the safety of the cryopreserved sperm in breeding production by assessing the fertilization capacity, embryo development, and larval growth. [ABSTRACT FROM AUTHOR]

Sparing marine-origin protein and lipid was investigated in diets for giant grouper ( Epinephelus lanceolatus ), using various combinations of soybean meal (SBM), soy protein concentrate (SPC), and an algal meal derived from Schizochytrium limacinum (ALG) to replace fish meal (FM), squid meal (SQM) and fish oil (FO). Diets were formulated to contain 45% protein (dry weight) and 10% lipid. Three diets were derived from this formulation, using combinations of SBM, SPC, and ALG to replace 20% (FM80), 40% (FM60), or 80% (FM20) of the marine-origin protein sources; additionally, incorporation of the lipid-dense ALG resulted in complete FO replacement in the FM60 and FM20 diets. A feeding experiment was carried out in a seawater recirculating system with 12, 90-L tanks initially stocked with 6 fish each (individual weight = 45.9 ± 7.1 g) and maintained at 25 °C. Diets were assigned to tanks in triplicate, fish were fed to apparent satiation twice daily for 12 weeks, and growth rate, body composition, nutrient retention, survival, hepatosomatic index and intestinal integrity were subsequently evaluated. With the exception of retained lipid, the FM100, FM80, and FM60 diets all yielded equivalent (P > 0.05) growth and feed utilization. In comparison, weight gain, specific growth rate, feed intake, retained nitrogen and retained lipid were significantly reduced in fish fed the FM20 feed, whereas FCR was significantly elevated. Amino acid analysis of the diets indicated that methionine was limiting in the FM20 feed. Hepatosomatic index did not vary among treatments, but other aspects of body composition were affected. Carcass lipid and ash significantly decreased with marine ingredient inclusion; carcass protein also varied, though less appreciably and without a clear pattern. Fillet fatty acid profile reflected dietary composition. The FM100 diet yielded the highest fillet EPA content, whereas DHA content, DHA:EPA and n − 3:n − 6 ratios, and total long-chain polyunsaturated fatty acids increased with dietary inclusion of ALG. Histological analysis revealed progressive morphological changes to the distal intestine with higher levels of FM replacement, suggesting enteritis among fish fed the FM20 feed. It is concluded that a blend of SBM, SPC, and ALG can replace at least 40% of marine protein sources, and ALG can be used as the main lipid source in diets for E. lanceolatus without significantly affecting fish performance or condition. Statement of relevance The results of this work contribute to decrease the dependence on protein and lipids from reduction fisheries traditionally used in commercial feeds for carnivorous fish, potentially improving the sustainability of aquaculture production of marine fish. [ABSTRACT FROM AUTHOR]

The present study aims at the microbiological analysis of export oriented frozen fishes, namely, Jew fish, Tongue Sole fish, Cuttle fish, Ribbon fish, Queen fish, and fish processing water and ice from a view of public health safety and international trade. Microbiological analysis includes the determination of total viable aerobic count by standard plate countmethod and enumeration of total coliforms and fecal coliforms bymost probable numbermethod. The presence of specific fish pathogens such as Salmonella spp. and Vibrio cholerae were also investigated. The TVAC of all the samples was estimated below 5 × 10 5 cfu/g whereas the total coliforms and fecal coliforms count were found below 100 MPN/g and 10 MPN/g, respectively, which meet the acceptable limit specified by International Commission of Microbiological Specification for Food. The microbiological analysis of water and ice also complies with the specifications having TVAC < 20 cfu/mL, and total coliforms and fecal coliforms count were below the limit detection of the MPN method. Specific fish pathogens such as Salmonella sp. and V. cholerae were found absent in all the samples under the investigation. Fromthis study, it can be concluded that the investigated frozen fishes were eligible for export purpose and also safe for human consumption. [ABSTRACT FROM AUTHOR]

Gelatin extraction from the skin of giant grouper (Epinephelus lanceolatus) was conducted by acid process with a yield of 20.27 g/100 g wet skin sample. The characteristics of extracted gelatin from giant grouper was investigated in this study, and further compared to that from commercial tilapia. Results showed that when compared to commercial tilapia, giant grouper had lower levels of bloom strength and foam formation ability, but greater values of viscosity, foam stability, and lightness (L*) on gelatin skin. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis revealed three high-bands intensities of major protein components of giant grouper skin gelatin, representing α1-chain, α2-chain, and β-components, and was similar to that of standard calf skin collagen type I. Compared to giant grouper, commercial tilapia contained extra proteins with molecular weight less than 70 kDa on the sodium dodecyl sulphate-polyacrylamide gel electrophoresis of both skin gelatins. [ABSTRACT FROM PUBLISHER]

Atlantic goliath grouper, Epinephelus itajara (Lichtenstein, 1822), presence, abundance, and size distribution were assessed during monthly underwater visual surveys at natural and artificial reefs in the central eastern Gulf of Mexico (7–50 m depth). Atlantic goliath grouper were more likely to be present, and to occur in greater abundance, at artificial reefs. Abundance was positively related to vertical relief and structural volume, and the largest numbers of individuals were observed at high volume artificial reefs (e.g., shipwrecks). This was likely due to greater refuge availability provided by artificial reefs within the study region, where structurally comparable natural habitats are rare. Atlantic goliath grouper measured via underwater video ranged in size from 36 to 214 cm total length (TL; median = 121 cm). No relationship was observed between TL and site depth or reef type. Tagged individuals were documented to move distances ranging 10–203 km, but the majority of tag return data indicated high site fidelity. The strong site fidelity of goliath grouper combined with their continuous and predictable association with artificial reefs allows for relatively efficient monitoring of individuals within a given region; however, these traits also increase vulnerability to exploitation and underline the need for cautious management. [ABSTRACT FROM AUTHOR]

While juvenile Atlantic goliath grouper, Epinephelus itajara (Lichtenstein, 1822), are known to depend on mangrove root structure, relationships with water properties (e.g., salinity) and depth remain unclear or understudied. Because availability of suitable mangrove habitat has been suggested as the primary bottleneck to the recovery of this threatened species in the US, we investigated habitat associations of juvenile Atlantic goliath grouper with respect to physical water properties within mangrove habitats. Our study was conducted in six coastal rivers and three canals within the Ten Thousand Islands region of southwest Florida. Results suggested that juvenile Atlantic goliath grouper differed in how they associated with specific mangrove habitats based on season and size. We found that smaller juveniles (<340 mm TL) appeared to have stronger associations to physical water characteristics than larger (≥340 mm TL) juveniles. Both large and small juveniles showed the strongest associations with DO (i.e., >3 mg L) within mangrove habitat. For small juveniles, extreme temperatures influenced habitat association; for large juveniles, extreme salinity influenced distribution. We also found evidence that juvenile Atlantic goliath grouper associated more with natural rivers over man-made canals. The present study has utility for delineating suitable mangrove habitats for protection and potentially in the design of sampling surveys that aim to estimate population abundance. [ABSTRACT FROM AUTHOR]

Six fish meal basal diets supplied with 0 (control), 0.25, 0.5, 1, 2.5 and 5 g kg−1 of choline chloride, resulting in choline levels of 2.57, 2.67, 2.94, 3.84, 4.99 and 7.71 g kg−1, respectively, were fed to giant grouper, Epinephelus lanceolatus, for 56 and 30 days to evaluate the growth and lipid metabolism, and stress tolerance respectively. In the first trial, fish fed different levels of choline-containing diets for 56 days had no significant difference in weight gain, survival and feeding efficiency. Fish fed increased levels of dietary choline, however, tended to have decreases in the hepatic somatic index; lipids, triglycerides, and cholesterol in liver; and triglycerides and cholesterol in serum. A decrease of lipid content in dorsal muscle was recorded in fish fed the diets containing choline >2.94 g kg−1. Additionally, dietary choline improved the reactions of fish to ammonia stress, including survival and behavioural responses, in fish fed diets containing choline levels >2.94 g kg−1. These findings indicate that choline plays important roles in lipid metabolism and stress tolerance in giant grouper. [ABSTRACT FROM AUTHOR]

A ranavirus was isolated from the diseased farmed groupers (Grouper iridovirus in genus Ranavirus, GIV-R), Epinephelus hybrids (blotchy rock cod, Epinephelus fuscoguttatus ♀ × giant grouper, Epinephelus lanceolatus ♂), in Sanya, Hainan, in July 2013. In this study, susceptibility of farmed juvenile giant grouper E. lanceolatus to GIV-R was determined by intraperitoneally injection. The cumulative mortality reached to 81% at 5 day post infection. Histologically, severe degeneration with massive pycnotic nuclei in spleen and kidney tissues was observed, and some small-size inclusion body-bearing cells (IBCs) existed in spleen. Hemorrhage and infiltration of inflammatory cells were presented in gill, liver and heart along with tissue degeneration and necrosis of varying severity. The results of immunohistochemistry analysis showed that the strongest immunolabellings were obtained from the kidney and spleen tissues, while intermediate intensity signals were observed in the heart, stomach, gill and liver tissues, and the weakest signals were obtained from the intestine and brain, but no signal was obtained in eyes. Electron microscopy revealed that spleen of moribund fish contained many viral particles in cytoplasm. Interestingly, in surviving fish, abnormal hypertrophic cells were observed in both splenic corpuscle and renal corpuscle, while no hypertrophic cell was observed in the other parts of spleen and kidney tissues. Moreover, immunolabellings only stained the hypertrophic cells in splenic corpuscle and renal corpuscle. This indicated that splenic corpuscle and renal corpuscle play an important role in GIV-R infection and replication. [ABSTRACT FROM AUTHOR]

Growth hormone (GH) performs important roles in regulating somatic growth, reproduction, osmoregulation, metabolism and immunity in teleosts, and thus, it has attracted substantial attention in the field of aquaculture application. Herein, giant grouper GH (ggGH) cDNA was cloned into the pET28a vector and expressed in Shuffle® T7 Competent Escherichia coli . Recombinant N-terminal 6× His-tagged ggGH was produced mainly in insoluble inclusion bodies; the recombinant ggGH content reached 20% of total protein. For large-scale ggGH production, high-cell density E. coli culture was achieved via fed-batch culture with pH-stat. After 30 h of cultivation, a cell concentration of 41.1 g/l dry cell weight with over 95% plasmid stability was reached. Maximal ggGH production (4.0 g/l; 22% total protein) was achieved via mid-log phase induction. Various centrifugal forces, buffer pHs and urea concentrations were optimized for isolation and solubilization of ggGH from inclusion bodies. Hydrophobic interactions and ionic interactions were the major forces in ggGH inclusion body formation. Complete ggGH inclusion body solubilization was obtained in PBS buffer at pH 12 containing 3 M urea. Through a simple purification process including Ni-NTA affinity chromatography and refolding, 5.7 mg of ggGH was obtained from 10 ml of fed-batch culture (45% recovery). The sequence and secondary structure of the purified ggGH were confirmed by LC–MS/MS mass spectrometry and circular dichroism analysis. The cell proliferation-promoting activity was confirmed in HepG2, ZFL and GF-1 cells with the WST-1 colorimetric bioassay. [ABSTRACT FROM AUTHOR]

The objective of this study was to adapt juvenile Pacific goliath grouper to a diet of pelleted feed. Groupers were captured in nature, individually marked, and randomly assigned to two groups. One group was fed pieces of raw fish and the second group a pelleted feed. The experiment lasted 12 weeks, and adaptation to the pelleted feed was done gradually. Fish growth, weight gain, and specific growth rate (SGR) were estimated. The Student’s t-test, at the 0.01 level of significance, was used to compare SGR means. All the fish survived. The rate of growth for grouper fed pieces of raw fish was 1.6 g per day. Although the groupers fed the pellets lost weight at the beginning of the experiment, at the end their SGR was 5.5 grams per day. The average weight gain for juvenile grouper fed pellets was 14.6 ± 4.1 g per day. [ABSTRACT FROM AUTHOR]

A new marine fish cell line, derived from the heart of giant grouper, Epinephelus lanceolatus ( Bloch), was established and characterized. The cell line was designated as ELGH and subcultured with more than 60 passages. The ELGH cells were mainly composed of fibroblast-like cells and multiplied well in Leibovitz's L-15 medium supplemented with 10% foetal bovine serum (FBS) at 28 °C. Chromosome analysis indicated that the modal chromosome number was 48. The fluorescent signals were detected in ELGH when transfected with green fluorescent protein reporter plasmids. The 50% cytotoxic concentration ( CC50) of the extracellular products ( ECPs) from Streptococcus iniae and Vibrio alginolyticus E333 on ELGH cells was 60.02 and 12.49 μg mL−1, respectively. Moreover, the ELGH cells showed susceptibility to Singapore grouper iridovirus ( SGIV), but not to soft-shelled turtle iridovirus ( STIV), red-spotted grouper nervous necrosis virus ( RGNNV) and spring viremia of carp virus ( SVCV), which was demonstrated by the presence of a severe cytopathic effect ( CPE) and increased viral titres. In addition, electron microscopy observation showed that abundant virus particles were present in the infected cells. Taken together, our data above provided the potential utility of ELGH cells for transgenic and genetic manipulation, as well as cytotoxicity testing and virus pathogenesis. [ABSTRACT FROM AUTHOR]

Despite uncertainties surrounding the protected Atlantic goliath grouper's stock size and resilience, fishery managers are under pressure to end the harvest moratorium in place since 1990. The present study sought to measure the proportion of anglers interested in reopening the goliath grouper fishery and to identify key reasons for this interest. We also present an estimate of the amount that anglers would be willing to pay for a goliath grouper harvest tag (the right sold to an angler to harvest one goliath grouper). A survey was mailed to a random sample of Florida (USA) residents with a recreational fishing license. Approximately half of the respondents agreed that the goliath grouper should now be open to recreational take. A probit analysis indicated that the best predictor for the opinion the fishery should be open is the belief that there are “too many goliath grouper.” Also, more anglers agreed than disagreed that goliath grouper are eating “all the fish on the reef,” a belief that was related to anglers personally viewing goliath grouper depredation. The mean willingness to pay for a goliath grouper harvest tag was estimated to be between $34 and $79. This information can be used to estimate the potential revenues available from a hypothetical tag system and can be compared with the economic value of goliath grouper in non-consumptive uses such as recreational diving. [ABSTRACT FROM AUTHOR]