Development of new assessment methods for Acropora coral recruitment using coral settlement devices and holes of marine block

We developed new assessment methods for Acropora coral recruitment using coral settlement devices (CSDs) and holes of a marine block. Both devices were deployed in situ before mass spawning of Acropora corals. The CSDs were sampled after 3–4 months of spawning to measure early recruitment, whereas holes of the marine block were observed underwater or MB was sampled to observe holes after 1 year of spawning to measure the recruitment. By combining the results, we would know the recruitment (visually identified underwater) in reefs, including the amount of early recruitment (identified by stereomicroscopic methods), and the environmental condition of the coral reef. These results would help to predict the future of a reef. Nagura Bay had a high early Acropora recruitment; however, due to competition with algae and sedimentation, the recruitment of juvenile corals was extremely low. The reef would possibly be healthy and sustainable at sites where both the early recruitment and recruitment are high. However, if both are low, the reef will be in a critical condition where urgent restoration will be required.     

Development of ceramic settlement devices for coral reef restoration using <Emphasis Type="Italic">in situ</Emphasis> sexual reproduction of corals

A ceramic coral settlement device (CSD) was developed to raise juvenile corals in situ in preparation for transplantation. The CSD is designed to be deployed in the water before mass spawning of corals, allowing larvae to settle and grow on the CSD before it is fixed to the reef structure. CSDs were aggregated and fixed on 0.2-m² frames (either 648 or 720 CSDs per frame) and deployed in the Sekisei Lagoon around the full moons of April and May in 2002. Seven frames were collected in August 2002 and settled corals were counted in the laboratory. The maximum number of coral colonies settled on CSDs in one frame was 617, with 94% belonging to the genus Acropora. The aggregated CSDs successfully functioned as a coral settlement substratum, with more appropriate arrangement of CSDs on the frame, enabling greater exposure to sunlight and currents, which is expected to increase the amount of settlement.     

Development of a coastal environment assessment system using coral recruitment

A new method for assessing coastal environments using the reproduction potential of corals has been developed and examined in situ. Six assessment racks were deployed before the full moon of May 2006 at three sites located around a river outlet in Nagura Bay, Ishigaki Is. and at one control location in Sekisei Lagoon. Each rack was equipped with two marine blocks (MB) containing 378 holes, two cases of coral settlement devices (CSDs), each containing 120 CSDs, and a water temperature logger. Assessment was based on recruitment of Acropora due to mass spawning. After 4 months of deployment, the surface of assessment racks showed apparent biofouling depending on sites mainly by algal settlement on the surfaces. Almost all the holes of the MBs were partly occupied, mainly by turf algae. Nagura Bay was thought likely to be an “unhealthy” coral reef due to runoff from land. However, our assessment showed that there were 0.85 corals per CSD in the Bay, compared with 0.51 in Sekisei Lagoon, indicating that coral larvae supply is not the cause of the unhealthy condition of corals in the Nagura Bay.     

Interspecific differences in the post-settlement survival of <Emphasis Type="Italic">Acropora</Emphasis> corals under a common garden experiment

Extremely low post-settlement survival is one of the largest barriers for artificial rehabilitation of Acropora corals. However, little data have been found for interspecific difference of the post-settlement survival probably because the observation of coral juvenile is difficult in the field. Here, we analyzed the survival of three dominant species of Acropora corals (A. digitifera, A. tenuis, A. yongei), with different colony morphologies and habitat preferences, for 2 years after settlement under the same environmental conditions. The post-settlement survival was significantly higher for A. tenuis than for A. digitifera 3 months after settlement. Two years later, the survival rate of A. tenuis was approximately 15 times higher than A. digitifera. In a separate analysis of three bottle-brush species (A. awi, A. echinata, A. subglabra) and A. tenuis, post-settlement survival was always higher for A. awi than for other two bottle-brush species, suggesting that the initial survival was different among morphologically sister species. Low survival was possibly associated with slow growth rates during the first 7 months. Thus, species selection is important for successful artificial coral rehabilitation, with A. tenuis being the most viable option. Alternatively, new techniques are required to improve post-settlement survival of slow growing coral species.     

Reproductive cycle of Aulacomya ater [Bivalvia: Mytilidae (Molina 1782)] in Punta Arenas Cove (Antofagasta Region,Chile)

Changes in the condition of broodstock, presence of larvae, and post-larval settlement of A. ater in Punta Arenas Cove (Antofagasta Region, Chile) were used to determine its reproductive cycle. The condition used as a spawning indicator shows that these events occur in three periods throughout the year (May–July, August–November, and December–February). Intense periods recorded in October–November and December–February coincided with periods in which the water temperature descended to less than 13 °C. Simultaneously, plankton samples indicated constant presence of A. ater larvae at this site, with large increases in abundance during August and between October and January, reaching a maximum of 2,192 larvae m^?3 in October. The periods of increase in larval abundance coincide with spawning periods; however, the greatest abundances were recorded before the start of the descent of the spawning indicator of the population under study. Monthly installation and replacement of collectors, after recording the first spawning, showed the permanent settlement of A. ater post-larvae over the course of the study, with a period of greater intensity occurring from the end of August to the end of January, registering peaks in October and November with 5,667 and 4,183 post-larvae × 600 cm² collector^?1, months which also coincide with the greatest larval abundance. The presence of larvae and post-larvae of the mytilids Choromytilus chorus and Semimytilus algosus was also recorded alongside A. ater larvae and post-larvae. Ch. chorus presented a cycle very similar to that of A. ater in both stages, with a maximum abundance of 4,531 larvae m^?3 in November and 13,533 post-larvae × 600 cm² collector^?1 in December.     

Genetic variations within Symbiodinium clade C among zooxanthellate corals (Scleractinia) in the temperate zone of Japan

In a recent study most of the temperate-living corals were found to harbor stress-sensitive Symbiodinium clade C, which is common in the tropical zone. In this study, we investigated the genetic variations within Symbiodinium clade C among corals living in temperate waters of Japan (17 genera; 26 species) using rDNA internal transcribed spacers (ITSs) to clarify the genetic differences between climatic zones. We also focused on two widespread coral species, Acropora hyacinthus and Pocillopora damicornis, to compare the genetic differences of Symbiodinium clade C between subtropical and temperate regions. We found multiple haplotypes of Symbiodinium ITSs in clade C, which formed nine subclades. Our data indicate that five genera (Acropora, Cyphastrea, Stylocoeniella, Porites, Pocillopora) contained host-specific Symbiodinium, while members of the family Faviidae and others contained several Symbiodinium ITS haplotypes from two or three subclades. A comparative analysis using Acropora and Pocillopora also revealed that the temperate zone coral population formed a single subclade of Symbiodinium clade C that was genetically isolated from those of subtropical populations. In summary, the majority of corals living in temperate waters of Japan, such as faviid corals, have several ITS haplotypes which possibly are utilized as an opportunistic survival strategy under severe environmental conditions, whereas Acropora and Pocillopora at the very least harbor temperate zone-specific Symbiodinium.     

SEM observations on larval shell morphology of Manila clam Ruditapes philippinarum and their utility

Manila clam Ruditapes philippinarum is common and abundant on Japanese tidal flats, forming a commercially important clam fishery. However, annual catches of Manila clam have decreased drastically since 1975?C1985. To study larval recruitment processes of Manila clam, we carried out scanning electron microscopy (SEM) observations on larval and juvenile shells of clams reared at 20 and 24?°C. There was no significant difference in final shell length of trochophores between 20 and 24?°C. However, the larval duration was much longer and the shell length of settled size of pediveligers was much larger for clams reared at 20?°C than those reared at 24?°C. These findings suggest that larval duration and growth, as well as settlement size, may vary markedly depending on temperature (and probably on season). The larval shell morphology of Manila clam can provide essential information about larval recruitment processes.     

Occurrence and distribution during the post-settlement stage of two Choerodon species in shallow waters around Ishigaki Island, southern Japan

The recruitment patterns of black-spot tuskfish Choerodon schoenleinii were compared with those of orange-dotted tuskfish (OT) C. ancholago. Individuals at the settlement and juvenile stages were collected using a push net in the intertidal zone and a seine net in seagrass beds. Relative values of standard length to total length (TL) for the two Choerodon species indicated an inflection point at approximately 10?C20?mm TL, suggesting that both species complete metamorphosis at a similar size. However, their temporal and spatial occurrence patterns were distinct. Newly settled individuals (postflexion stage) of black-spot tuskfish were collected mainly within foliage of Sargassum plants of the intertidal zone around March?CApril, while those of OT occurred in both the intertidal zone and seagrass beds mainly in May and June. In seagrass beds, the abundances of both species increased from May or June; however, the TL of black-spot tuskfish was bigger than that of OT. Therefore, black-spot tuskfish progressively migrate to seagrass beds after settling and completing metamorphosis in the intertidal zone, indicating that they utilize two different habitats as nursery grounds. Early spawning and migration from the intertidal zone by this species contributed to the occurrence of relatively large individuals in seagrass beds.     

In situ growth and mortality of juvenile Acropora over 2 years following mass spawning in Sekisei Lagoon,Okinawa (24°N)

The growth of Acropora in Sekisei Lagoon was investigated in situ using ceramic coral settlement devices (CSDs) and marine blocks (MBs) with small holes on their surfaces that were deployed prior to a mass spawning event. Acropora that had settled in 10-mm holes on the upper surface of the MBs were found to have grown inwards after 348 days post-mass spawning. After 733 days, the colonies had grown outwards, encrusting the blocks and attaining a maximum diameter of 21.5 mm (3.7 mm). CSDs that had been stacked above each other on frames were separated and observed in situ on 405 and 764 days after mass spawning. After 405 days, the maximum diameter of the encrusting Acropora was 7.6 mm (±2.4 mm), which increased to 19.4 mm (±5.5 mm) after 764 days, with 30% of colonies extending short branches. The length of the branches of Acropora grown on the CSDs fixed to the MBs 3 months after the mass spawning event exceeded the size of the encrusting portion of the colony 629 days after spawning. The mortality of colonies between 1 and 2 years was slight, with the temperatures conducive to coral bleaching that occurred during the study also having only a slight effect.     

Ontogenetic habitat shift of age-0 Japanese flounder <Emphasis Type="Italic">Paralichthys olivaceus</Emphasis> on the Pacific coast of northeastern Japan: differences in timing of the shift among areas and potential effects on recruitment success

Ontogenetic habitat shift and feeding habits in the shallow (< 15 m) and deep (30–80 m) habitats of age-0 Japanese flounder Paralichthys olivaceus in Sendai Bay, the Pacific coast of northeastern Japan, were examined to understand the mechanisms that potentially enable area-specific high recruitment success. The flounder was able to use the shallow nursery habitat for about 1 year, until the next summer of their settlement (June–August) when they had reached 250 mm total length (TL). In addition, age-0 flounder between 150 and 250 mm TL used both shallow and deep habitats from winter to the next summer of their settlement, where species, size, and availability of potential food and susceptibility to predators are considerably different. These area-specific characteristics in Sendai Bay are clearly different from other areas around Japan that have been described in the literature: shorter residence in the shallow habitat and smaller size at emigration to the deep habitat. The characteristics in Sendai Bay seem to be enabled by prolonged good feeding conditions in the shallow habitat, which result from an abundant food supply and relatively lower temperature that does not exceed the uppermost temperature (25 °C) for maximum growth of the age-0 flounder. We consider that the prolonged better feeding conditions in the shallow habitat in the study area for ca. 1 year after settlement contribute to higher recruitment success.     

Age and maturation of jack mackerel Trachurus japonicus in the East China Sea

Growth and reproductive characteristics of jack mackerel Trachurus japonicus collected in the East China Sea were determined based on otolith readings and gonad histology, respectively. Translucent and opaque zones on sectioned otoliths were identified and opaque rings counted. Von Bertalanffy growth parameters did not significantly differ between males and females, and the combined growth curve was: L _t  = 401{1 ? exp[?0.275 (t + 1.149)]} (0.8 < t < 6.9), where L _t is fork length (mm) at age t. The calculated lengths at age 1 in our study were larger than those reported 50 years ago from the East China Sea. The spawning period was evaluated to be from December to June, but primarily from February to May, based on the monthly changes in the gonadosomatic index and histological observations. The minimum size and age at first maturity were smaller and younger, respectively, than those reported in previous studies.     

Occurrence and distribution of settling and newly settled spotted halibut Verasper variegatus and Japanese flounder Paralichthys olivaceus in shallow nursery grounds around Shimabara Peninsula, western Japan

The occurrence and distribution of settling and settled spotted halibut Verasper variegatus were compared with those of Japanese flounder Paralichthys olivaceus in shallow habitats around Shimabara Peninsula, western Japan, to elucidate the settlement and recruitment characteristics of spotted halibut, a rare pleuronectid flatfish in Japan. Push-net sampling conducted at nine sites in March and April 2003 collected spotted halibut from four nurseries located at eastern areas of Shimabara Peninsula in Ariake Bay; Japanese flounder were sampled from eight nurseries. Comparison of microhabitat distributions in a tidal-flat nursery during February?CApril in 2003?C2007 revealed that metamorphosing larvae and juveniles of spotted halibut, which showed the drastic body coloration (black to brown) and behavioral changes (frequent swimming to settlement), were distributed mainly in the lower edge of the intertidal area, whereas Japanese flounder inhabited both intertidal and subtidal areas. Metamorphosing larvae of spotted halibut (12.6?C16.5?mm standard length; n?=?24) were collected in March when the highest densities were observed, whereas metamorphosing larvae of Japanese flounder (10.0?C15.9?mm, n?=?55) were observed during March?CApril. Our results suggest that spotted halibut has a narrower time/space window for recruitment to the specific nurseries compared with Japanese flounder.     

Hatchery broodstock conditioning of the blue mussel <Emphasis Type="Italic">Mytilus edulis</Emphasis> (Linnaeus, 1758). Part II. New formulated feeds offer new perspectives to commercial hatcheries

Five diets were compared for their efficiency at maturing the gonads of the blue mussel, Mytilus edulis. The diets consisted of a 1:1:1 mixture of Isochrysis galbana (T-Iso), Pavlova lutheri, and Chaetoceros calcitrans given at concentrations of 2.4 × 10¹¹ cells day^?1 for the positive control treatment (PF) and 3.0 × 10¹⁰ cells day^?1 (=1/8) for the negative control treatment (NF). The other three treatments, MB10+, MyStock+, and Frippak+, consisted of the NF diet supplemented with one of the micro-encapsulated diets MB10 (mixture of dried algae), MyStock (formulated diet), and FRiPPAK^® Fresh #1 CAR (larval shrimp diet) at a level of 0.2% of the live weight (LW). Treatments PF, MB10+, and MyStock+ led to high percentages of spawning animals (80, 78, and 85%, respectively) and large numbers of eggs (on average 3.0 × 10⁶ eggs female^?1). Females given the NF and Frippak+ treatments produced only half the number of eggs per female, and only 17 and 6%, respectively, of the animals spawned. A high hatching rate was observed for all treatments, 71% for the pure algae diets PF and NF and more than 80% for the micro-encapsulated diets. The larvae resulting from the NF treatment were smaller, with 41% of D-larvae measuring less than 90 μm, whereas with the other treatments only 5–11% belonged to that size category. The four most important fatty acids found in mussel eggs were 16:0, 16:1(n?7), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA); these represented at least 50% of the fatty acids in all treatments. The high DHA content of MB10 and MyStock was not reflected in the fatty acid composition of the eggs whereas the high concentration of linoleic acid in MyStock was. To our knowledge, this is the first time that mussels are successfully conditioned with formulated feeds.     

The impact of the adult blue mussel (Mytilus edulis) population on settling of conspecific larvae

The choice of a mussel bed as a settling locality by conspecific mussel larvae is a trade-off between reduced fitness due to an increased risk of larval predation and post-settling food competition with the filtering adults and the benefit from a reduced post-settling mortality. This reduced post-settling mortality may be due to a reduced benthic predation in habitats with high complexity. In a field experiment, the larval settling of blue mussels, Mytilus edulis, was recorded on an artificial substrate 0.25, 1 and 2 m above the bottom during six periods in spring 1999. The experiment was conducted at four stations with dense mussel beds located at two of these stations. Two of the four stations, one with mussel beds and one without, were located in a wind-exposed area and the two other stations in a sheltered area. It was demonstrated that the larval settling was reduced up to 1 m above the mussel beds. A size analysis of the settled mussels indicated that the reduction in settling intensity close to mussel beds was due to a pre-settling process: the larvae were predated by the filtering adult mussels. Settling was significantly affected by wind stress. During periods with a high mean wind velocity and a turbulent water column, the larvae showed a reduced settlement 1 m above a mussel bed relative to 2 m above, whereas the same patterns not could be observed outside a mussel bed. The importance of the filtration activity of the adult mussels and the behaviour of the larvae is discussed. The recruitment of blue mussels into a mussel bed was investigated. Here, significant positive correlations were observed between the density of recruits and density of adult mussels and weights of empty shells. This indicates that the filtering mussels not only increase the mortality of larvae, but also serve as an important substrate reducing post-settling predation from benthic predators.     

Feeding,somatic condition and survival of sand lance <Emphasis Type="Italic">Ammodytes</Emphasis> sp. larvae in Mutsu Bay,Japan

To clarify the recruitment process of sand lance Ammodytes sp., we investigated larval condition factor, relative gut fullness (%GF), prey abundance and oceanographic structure in Mutsu Bay, Japan, during 1999–2001. Ammodytes sp. larvae, which were collected by horizontal hauls of Motoda nets and a ring net at depths of 1, 10, 20, 30 and 40 m, were mainly distributed at 10–30 m. Larvae at the first feeding time until 12 mm in body length (BL) fed predominantly on copepod nauplii, whereas large larvae with BL of 12.1–14.0 mm fed on a mixture of copepod nauplii, copepodites and appendicularians from late February to April. A path analysis showed that difference in water density between 35- and 5-m depths negatively affected naupliar abundance at 10–30-m depth (standardised path coefficient β = ?0.71, p = 0.005 for 3.3–8.0-mm BL larvae and β = ?0.78, p < 0.001 for 8.1–12.0-mm BL larvae). Naupliar abundance positively affected the %GF of Ammodytes sp. larvae (β = 0.75, p < 0.001 for 3.3–8.0-mm BL larvae and β = 0.66, p < 0.001 for 8.1–12.0-mm BL larvae), whereas it was negatively affected by water temperature (β = ?0.45, p = 0.008 for 3.3–8.0-mm BL larvae and β = ?0.56, p = 0.002 for 8.1–12.0-mm BL larvae), and the temperature effect was weak compared with that of naupliar abundance. In turn, %GF positively affected larval somatic weight (β = 0.91, p < 0.001 for 6.0-mm BL larvae and β = 0.70, p = 0.005 for 10.0-mm BL larvae). The recruitment failure in 1999 was likely caused by a reduced condition factor, which resulted from low naupliar abundance. In contrast, the abundance of nauplii and Oithona similis copepodites was high in 2000 and 2001. It is possible that the higher recruitment success in 2001 was because of the higher water temperatures in Mutsu Bay, sustaining faster growth of the larvae than in 2000 under the high-prey abundance conditions.     

Implications of larval diet concentration on post-larval yield in a production scale flow-through system for scallops (Pecten maximus Lamarck) in Norway

In order to optimize Pecten maximus larval performance and post-larval yield, larvae were fed five algal concentrations in the range 3–20 cells μL^?1 in 2,800-L flow-through tanks without prophylactic antibiotics. Competent larvae were transferred to a commercial hatchery for settlement and provided uniform conditions for 4 weeks to observe effects. Increased diet concentration increased the sum of fatty acids (FA) in the total larval population, reaching 7 and 25 ng FA larvae^?1 at 3 and 16 cells μL^?1, respectively. The FA level in competent larvae was not affected by diet concentration and ranged from 30 to 46 ng larvae^?1. Increased diet concentration increased larval growth rate, and the larvae were ready to settle 5 days earlier when fed 16 cells μL^?1 compared to 3 cells μL^?1. Larval ingestion rate increased during life span and with increased larval diet concentrations, but a considerable amount (40–60 %) of the added algal cells was lost from the larval rearing tanks due to the seawater flow. There was no effect on larval survival, final post-larval shell height, % of competent larvae transferred to settlement, or total yield of post-larvae. Final mean post-larval shell height was 509 μm and 25.5 % of competent larvae settled, resulting in a final post-larval yield between 6.9 and 17.6 % of the initial number of d3 larvae. Competent larvae with similar FA content produced similar numbers of post-larvae independent of diet concentration, even if higher diet concentrations resulted in higher rates of larval development and metamorphosis.     

Fishery characteristics of barfin flounder Verasper moseri in southern Tohoku,the major spawning ground,after the start of large-scale stock enhancement in Hokkaido,Japan

Commercial landings of a rare pleuronectid flatfish, barfin flounder Verasper moseri, recovered drastically after large-scale stock enhancement in Hokkaido conducted since 2006. This study investigated commercial landings, fishing grounds, size distributions, and sex and age compositions of barfin flounder during 2007–2011 in southern Tohoku, their major spawning ground, which is over 700 km south of Hokkaido. Landings, mostly comprising stocked fish, increased drastically in southern Tohoku: from 2.0 tons in 2007 to 20.8 tons in 2010. Over 98 % of them were landed during January–April, with the peak period during February–March. Fishing logbook data of offshore bottom-trawl vessels during 2007–2010 revealed the upper continental slope off southernmost Tohoku as the main fishing ground (35°40′–36°50′N, annual weighted mean depth 267–299 m). Two size modes in the landings consisted of males (ca. 40 cm) and females (ca. 60 cm). The main age at fishery recruitment in southern Tohoku was younger for males (age 2+) than for females (ages 3+ and 4+), the result of which was that the female percentage was lowest at 1.5 % in 2009 and highest at 7.9 % in 2011. Our results showed clearly how the effectiveness of large-scale stock enhancement in Hokkaido extended to southern Tohoku in association with spawning migration of stocked barfin flounder.     

Potential for production of ‘mini-mussels’ in Great Belt (Denmark) evaluated on basis of actual and modeled growth of young mussels Mytilus edulis

The present study is a first step towards evaluation of the potential for line-mussel production in the Great Belt region between the Kattegat and Baltic Sea, Denmark. We present experimental results for actual growth rates of juvenile/adult mussels Mytilus edulis in suspended net bags in terms of shell length and dry weight of soft parts during extended periods (27–80 days) in the productive season in the first 6 series of field experiments, including 4 sites in Great Belt and 2 sites in Limfjorden, Denmark. Data were correlated and interpreted in terms of specific growth rate (μ, % day^?1) as a function of dry weight of soft parts (W, g) by a previously developed simple bioenergetic growth model μ = aW ^?0.34. Results were generally in good agreement with the model which assumes the prevailing average chlorophyll a concentration at field sites to essentially account for the nutrition. Our studies have shown that M. edulis can grow from settlement in spring to 30 mm in shell length in November. We therefore suggest line farming of 30 mm ‘mini-mussels’ during one growth season, recovering all equipment at the time of harvest and re-establishing it with a new population of settled mussel larvae at the beginning of the next season, thus protecting the equipment from the damaging weather of the Danish winter season. The growth behavior during the fall–winter season was recorded in an additional 7th series of mussel growth experiments on farm-ropes to show the disadvantage of this period.     

Morphological and habitat characteristics of settling and newly settled Roughscale Sole Clidoderma asperrimum collected in the coastal waters of northeastern Japan

This report first describes the morphological and habitat characteristics of larval and juvenile Roughscale Sole Clidoderma asperrimum. Five metamorphosing larvae (22.1–31.7 mm standard length, SL) and 12 juveniles (23.7–46.4 mm SL) were collected from two locations in coastal waters of northeastern Japan, Shizugawa Bay (rocky habitats, 6–12 m depth) and Iwaki (sandy habitats, 10–50 m depth), respectively, using a hand net while SCUBA diving and a small trawl net during May–August in 2008 and 2010. Underwater observation in Shizugawa Bay revealed that metamorphosing larvae and juveniles that had settled on rocks or stones showed transparent and variegated body coloration, which is cryptic to a rocky habitat. Juveniles in Iwaki showed monotonic coloration. The settlement would occur during metamorphosis because the same larva observed on a stone subsequently swam with a left-lateralized body posture. The larval morphology was characterized by a dense covering of fine spines on the whole body surface. Spines on the ocular side developed steadily, gradually forming bony tubercles with growth, whereas those on the blind side regressed with development and finally disappeared in metamorphosed juveniles. Our results indicate that Roughscale Sole can settle and adapt to rocky and sandy habitats in coastal waters with wide depth range.     

A basic experiment of coral culture using sexual reproduction in the open sea

Coral larvae, produced from a mass spawning event, were successfully settled on special stone settlement sticks and raised in situ for eventual transport to other reefs. The test area, Sekisei lagoon, Okinawa Prefecture, Japan, is located close to the warm Kuroshio current and is surmised to be the source from which major Japanese corals are derived. A total of 131 settlement sticks, with small holes in their sides to increase protection from grazing (4 mm in diameter and approximately 5 mm deep), were deployed in the lagoon the day before the coral’s mass spawning. After 3 months, 61 sticks were recovered containing 71 corals, mostly in the holes. After 1 year, three corals were confirmed to be growing well and extending outside the holes of the three sticks out of 70 sticks left in the water at the lagoon site. They survived two potentially lethal conditions, that is, high water temperatures with associated extensive coral bleaching and continuous grazing pressure from predators. This procedure is applicable for large-scale coral transplantation, not only in Japan but also in other tropical countries.