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Acropora cervicornis is a structurally and functionally important Caribbean coral species. Since the 1980s, it has suffered drastic population losses with no signs of recovery and has been classified as a critically endangered species. Its rapid growth rate makes it an excellent candidate for coral restoration programs. In 2011, the Fundación Dominicana de Estudios Marinos (Dominican Marine Studies Foundation, FUNDEMAR) began an A. cervicornis restoration program in Bayahibe, southeast Dominican Republic. In this study, we present the methodology and results of this program from its conception through 2017, a preliminary analysis of the strong 2016 and 2017 cyclonic seasons in the greater Caribbean, and a genetic characterization of the “main nursery”. The mean survival of the fragments over 12 months was 87.45 ± 4.85% and the mean productivity was 4.01 ± 1.88 cm year−1 for the eight nurseries. The mean survival of six outplanted sites over 12 months was 71.55 ± 10.4%, and the mean productivity was 3.03 ± 1.30 cm year−1. The most common cause of mortality during the first 12 months, in both nurseries and outplanted sites, was predation by the fireworm, Hermodice carunculata. We identified 32 multilocus genotypes from 145 total analyzed individuals. The results and techniques described here will aid in the development of current and future nursery and outplanted site restoration programs. [ABSTRACT FROM AUTHOR]

Coral reef restoration is not the same as forest restoration as its success is not always guaranteed because of insufficient knowledge of coral biology. The technology of active restoration has a history of only 40 years or less. In spite of many devices and efforts, restoration is often hampered by low survivorship of colonies, fragments or sexual propagules. In order to enhance coral resilience and adaptation in a changing world, many new approaches to coral reef restoration are being suggested. However, we wouldn't be able to succeed or achieve expected result, i.e. recovery and thriving of the coral reefs, if outplanted coral recruits do not grow well and spawn and successfully fertilize in the sea. The cost to restore a few hectares of reef is often considerable. More studies are needed to improve the methodology. Contractors and practitioners of coral reef restoration projects must have advanced techniques supported by strong science for successful propagation, rearing, and transplantation/outplantation of corals. This review describes what we have learned so far from research on active coral reef restoration and discusses seven topics that may facilitate successful restoration projects. [ABSTRACT FROM AUTHOR]

Epilithic algae are a ubiquitous component of coral reefs. Components of the epilithic algal matrix (EAM) can have a significant influence on coral settlement and benthic feeding by fishes. We employed a herbivore exclusion experiment on a fringing reef in Viti Levu, Fiji, to investigate the functional role of herbivorous fishes in affecting the EAM between different habitat types and levels of community-based fishing restriction. We surveyed the herbivorous fish community and deployed experimental tiles on the reef flat and lagoonal slope and inside and outside of an area where fishing is restricted (tabu). Tiles were deployed for 3 months, half within cages to exclude herbivorous fishes. We then identified algal type and quantified epilithic algal turf height, sediment dry weight, and detritus within the EAM on each tile. EAM that developed under herbivory was remarkably similar, regardless of the differences in habitat or fishing restriction. In contrast, EAM within cages was characterised by longer turf, heavier sediment load, and high variance in turf length and sediment load. Habitat type played a strong role in determining EAM characteristics where herbivores were excluded. Caged EAM on the reef flat was characterised by algal turf and fleshy macroalgae, whereas EAM in cages on the lagoonal slope was overwhelmingly dominated by filamentous and mat-forming cyanobacteria. The results presented here demonstrate the importance of herbivorous fishes in maintaining a benthic environment favourable to coral settlement and survival. Our results suggest that herbivore biomass per se is not a reliable predictor of foraging activity. Moreover, these results show that the absence of herbivore foraging can have different consequences depending on the habitat type, even within the same reef. [ABSTRACT FROM AUTHOR]

Mesophotic coral ecosystems (below 30-40 m depth) host a large diversity of zooxanthellate coral communities and may play an important role in the ecology and conservation of coral reefs. Investigating the reproductive biology of mesophotic corals is important to understand their life history traits. Despite an increase in research on mesophotic corals in the last decade, their reproductive biology is still poorly understood. Here, gametogenesis and fecundity of the Indo-Pacific mesophotic coral , Acropora tenella, were examined in an upper mesophotic reef (40 m depth) in Okinawa, Japan for the first time. Acropora tenella is a hermaphrodite with a single annual gametogenic cycle, and both oogenesis and spermatogenesis occurring for 11-12 and 5-6 months, respectively. Timing of spawning of this species was similar to other shallow Acropora spp. in the region. However, colonies had longer gametogenic cycles and less synchronous gamete maturation compared to shallow acroporids with spawning extended over consecutive months. Both the polyp fecundity (number of eggs per polyp) and gonad index (defined as the number of eggs per square centimeter) of A. tenella were lower than most acroporids. Our findings contribute to understanding of the life history of corals on mesophotic reefs and suggest that the reproductive biology of upper mesophotic corals is similar to that of shallow-water corals. [ABSTRACT FROM AUTHOR]

Coral reefs are often subject to disturbances that can cause enduring changes in community structure and abundance of coral reef organisms. In Moorea, French Polynesia, frequent disturbances between 1979 and 2003 caused marked shifts in taxonomic composition of coral assemblages. This study explores recent changes in live cover and taxonomic structure of coral communities on the north coast of Moorea, French Polynesia, to assess whether coral assemblages are recovering (returning to a previous Acropora-dominated state) or continuing to move towards an alternative community structure. Coral cover declined by 29.7% between July 2003 and March 2009, mostly due to loss of Acropora and Montipora spp. Coral mortality varied among habitats, with highest levels of coral loss on the outer reef slope (7-20 m depth). In contrast, there was limited change in coral cover within the lagoon, and coral cover actually increased on the reef crest. Observed changes in coral cover and composition correspond closely with the known feeding preferences and observed spatial patterns of Acanthaster planci L., though observed coral loss also coincided with at least one episode of coral bleaching, as well as persistent populations of the corallivorous starfish Culcita novaeguineae Muller & Troschel. While climate change poses an important and significant threat to the future structure and dynamics coral reef communities, outbreaks of A. planci remain a significant cause of coral loss in Moorea. More importantly, these recent disturbances have followed long-term shifts in the structure of coral assemblages, and the relative abundance of both Pocillopora and Porites continue to increase due to disproportionate losses of Acropora and Montipora. Moreover, Pocillopora and Porites dominate assemblages of juvenile corals, suggesting that there is limited potential for a return to an Acropora-dominated state, last recorded in 1979. [ABSTRACT FROM AUTHOR]

Photosynthetic, growth, and reproductive characters for colonies of the massive coral Montastraea faveolata were measured at 3-m-depth and 18-m-depth populations in the Florida Keys in 1993 to investigate reproductive behavior across depth. I tested the hypothesis that reproductive traits would exhibit depth-related decreases similar to those documented for photosynthetically derived energy availability and growth rate. Colonies at the 18 m site had significantly reduced access to photosynthetically derived energy compared to colonies at 3 m depth. Linear skeletal extension rates were also reduced at the deep site (mean±SE; 3 m: 6.13 mm year-1±0.35; 18 m: 3.44 mm year-1±0.36; P<0.001). Contrary to expectations, depth did not affect most reproductive characters. Reproductive allocation, the amount of lipid invested in reproduction, was similar between depths (3 m: 3.74 mg lipid cm-2±0.55; 18 m: 3.88 mg lipid cm-2±0.62; P<0.8). Reproductive effort, the proportion of total lipid invested in reproduction, was also similar between sites (3 m: 41.4%±4.7; 18 m: 47.3%±7.12; P<0.163). Colonies within a depth did differ significantly in many gametic characteristics including eggs per gonad, total egg area, spermary area, total gonad area, and male allocation (the proportion of total gonad area invested in spermary tissue), but only total egg area differed between depths, and this was greater at 18 m (3 m: 55.63 μm2×104±4.76; 18 m: 60.51 μm2×104±3.41; P<0.035). Colonies at the two sites had similar polyp fecundity (egg production per polyp); however, a difference in polyp density between sites (3 m: 5.56 polyps cm-2±0.21; 18 m: 4.87 polyps cm-2±0.15; P<0.028) resulted in a significant reduction in area fecundity (egg production per square centimeter) at the 18 m site (3 m: 554 eggs cm-2±27.9; 18 m: 422 eggs cm-2±31.0; P<0.045). Thus, there was a depth-related fecundity cost arising from a change in colony architecture (i.e. polyp spacing) rather than a direct effect of depth on the number of eggs produced per polyp. Egg production per gonad was positively correlated between 1993 and 1994 (r=0.540, P<0.05), indicating that other reproductive characteristics may also be stable between years. [ABSTRACT FROM AUTHOR]

Presents a study which examined the reproductive ecology of two eastern Pacific zooxanthellate coral species. Materials and methods; Results and discussion.

Recruitment of scleractinian corals on settlement plates at Heron Island, Great Barrier Reef, was examined over four years (September 1991--September 1995) to quantify spatio-temporal patterns at different scales and to assess post settlement mortality. Recruitment was dominated by pocilloporid corals which accounted for 80.1% of the 8627 spat counted, whereas non-isoporan acroporlds represented only 16.4%. Poritids, faviids and isoporan acroporids rarely recruited to the plates (3.5%), despite their obvious abundance as adults on the reef. Recruitment patterns on the plates indicate strong space-time interactions as evidenced by patchy recruitment of both pocilloporid and acroporid spat. Interactions were found between space (on the scale of 102 m, i.e. sites within zones, and 101 m, i.e. racks within sites) and time (on the scale of years) for pocilloporids and between space (on the scale of 103 m, i.e. zones, and 102 m) and time (on the scale of years) for acroporids. Post-recruitment mortality of acroporid spat in the period 3--10 months after their major spawning was dependent on their initial recruitment density, but pocilloporid mortality was either independent of initialrecruitment density or, more likely, obscured by additional recruitment of pocilloporids to plates between late February and September. High rates of recruitment and growth by other sessile organisms, particularly bryozoans and oysters, appear to result in increased post-recruitment mortality and limit recruitment of scleractinian corals on settlement plates. The work reinforces an emerging picture that coral recruitment patterns are determined by mechanisms that manifest over a large range of spatial scales. [ABSTRACT FROM AUTHOR]