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In response to the increases in pCO2 projected in the 21st century, adult coral growth and calciWcation are expected to decrease significantly. However, no published studies have investigated the effect of elevated pCO2 on earlier life history stages of corals. Porites astreoides larvae were collected from reefs in Key Largo, Florida, USA, settled and reared in controlled saturation state seawater. Three saturation states were obtained, using 1 M HCl additions, corresponding to present (380 ppm) and projected pCO2 scenarios for the years 2065 (560 ppm) and 2100 (720 ppm). The effect of saturation state on settlement and post-settlement growth was evaluated. Saturation state had no significant effect on percent settlement; however, skeletal extension rate was positively correlated with saturation state, with ~50% and 78% reductions in growth at the mid and high pCO2 treatments compared to controls, respectively. [ABSTRACT FROM AUTHOR]

The local densities of heterospecifics and conspecifics are known to have profound effects .on the dynamics of many benthic species, including rates of settlement and early post-settlement survivorship. We described the early life history of the Caribbean coral, Siderastrea radians by tracking the population dynamics from recently settled planulae to juveniles. Through three years of observation, settlement correlated with the abundance of other benthic organisms, principally turf algae (negatively) and crustose coralline algae (positively), in addition, adult density showed independent effects on coral settlement and early post-settlement survivorship. Settlement rates increased across low levels of adult cover and saturated at a maximum around 10% cover. Early post-settlement survivorship decreased with adult cover, revealing structuring density dependence in coral settlers. The earliest life stages of corals are defined by low survivorship, with survivorship increasing appreciably with colony size. However, recent settlers (one-polyp individuals, <1 year old) are more likely to grow into two-polyp juveniles, than older single polyps (>1 year old) that were delayed in their development. The early benthic phase of corals is defined by a severe demographic bottleneck for S. radians, with appreciable density-dependent and density-independent effects on survivorship. For effective management and restoration of globally imperiled coral reefs, we must focus more attention on this little studied, but dynamic, early life history period of corals. [ABSTRACT FROM AUTHOR]

We studied (1) the dynamics of colonization by epilithic algae on mechanically damaged colonies of the coral Porites lutea, (2) the dynamics of algal colonization on dead coral fragments (coral pebbles), (3) and regeneration rates of the damaged corals under a broad range of natural light conditions on the fringing reef of Sesoko Island (Okinawa, Japan). After 1 month (of the experiment), 26 algal species occupied damaged coral areas with a projected areal cover of 1–7%. Colonizers were mainly diatoms, Cyanobacteria, filamentous green, brown and red algae. During this period, the algal settlers were not an impediment to coral polyp recovery. The recovery rate of damaged coral tissue was highest after the first month, amounting to approximately 0.15 mm day-1 under bright light (70–90% of incident surface photosynthetically active radiation, PAR0), 0.14 mm day-1 under moderate light (20–30% PAR0) and 0.07 mm day-1 under low light (2–5% PAR0). After 3 months, 58 algal species had settled onto lesions and 43 species onto coral pebbles. Projected areal cover of the algae was 30–90%. After the second month of the experiment, the recovery rates of corals declined sharply to 0.02–0.04 mm day-1. Under high and moderate light intensities, the measured parameters were similar (with the exception of the number of algal settlers). Under low light, the number, the density of algal settlers and the regeneration rate of polyps on damaged corals were significantly reduced. The algal turf community was formed under light intensities from 20% to 90% PAR0, but was not formed under low light. [ABSTRACT FROM AUTHOR]

Abstract: In coral aquaculture, sexual reproduction increasingly plays an important role for serving trade and reef restoration purposes. However, until coral juveniles reach a semi-stable size which makes them less vulnerable against algal growth and sedimentation, high mortality rates may occur in the first several weeks to months after settlement. In the present study, the influence of several food sources on the growth and survival of newly settled primary polyps was studied under laboratory conditions for 5 months. In order to estimate effects on specimens of both reproductive modes, experiments were carried out with the brooder, Favia fragum, and with the broadcast spawner, Acropora tenuis. Primary polyps kept in 2-liter aquaria were daily fed with freshly hatched Artemia salina, the micro algae Phaeodactylum tricornutum and a commercially available dry food (Nori Micro, Zoolife®), respectively, at various concentrations. Growth rates in both species were significantly higher in the Artemia treatment with maximum rates of 9.4±4.9 mm2 (mean±S.D.; d =5 months) for F. fragum and 26.8±10.3 mm2 (d =5 months) for A. tenuis compared to all other treatments and the control (no additional food). Survival in F. fragum was overall higher than 60% in all treatments with maximum rates of 85.0±12.6% at the highest Artemia concentration. Survival rates in A. tenuis ranged from 28.9±4.7% (lowest Nori concentration) to 86.2±5.9% (medium Artemia concentration). The present study shows that Artemia nauplii may greatly enhance the growth and partly enhance the survival of early sexual recruits which may significantly help to more rapidly overcome the early and most fragile post-settlement stages. As a consequence, the residence time for sexual coral recruits in cost- and labour-intensive hatcheries may be greatly reduced. [Copyright &y& Elsevier]

On reefs around Australia, coral mass spawning typically occurs during the austral spring (October/November) on the east coast, and during autumn (March/April) on the west coast. However, to investigate the incidence of a secondary spawning event in spring on the west coast, the reproductive state of corals was assessed on two reefs. The results indicated that of the 29 species of Acropora investigated, multiple colonies of 11 species spawned in late spring or in early summer, in contrast to previous reports of spawning during autumn. Additionally, of four species that were followed through time at one reef, two spawned in both spring and autumn, however, individual colonies had only one gametogenic cycle. Within a single site, conspecific colonies were reproductively isolated and may not interbreed, potentially representing the initial stage of sympatric speciation in these populations. [ABSTRACT FROM AUTHOR]

Abstract: The effects of enhanced ultraviolet radiation (280–400 nm: UVR) on the fecundity of Acropora cervicornis were measured in field-transplanted colonies from 20 m to 1 m depth and vice versa at La Parguera, Puerto Rico. Fecundity was estimated from histological sections made from tissue samples obtained at different time intervals during the experimental period (March – August 2003). All colonies transplanted from 20 m to 1 m showed a 100% reduction in gonads per mesentery per polyp one month after transplantation, while those transplanted from 1 m to 20 m did not show any significant reduction in fecundity throughout the experimental period. The latter colonies did show however, a delay in the spawning times by releasing their gamete bundles approximately two-three weeks after the controls at 1 m and two months after the controls at 20 m suggesting an induced response as a consequence of changes in their daily light cycle due to less radiation (PAR and UVR) available at 20 m compared to 1 m. Control colonies at 20 m spawned after the full moon of June 2003, while the controls at 1 m spawned 5–6 days after the full moon of July 2003. While a possible reabsorption of the gametes occurred in A. cervicornis colonies transplanted from 20 m to 1 m, the expulsion of these gametes due to the sudden stress caused by the transplantation is not discarded. The results suggest that sudden increases in UVR can completely stop sexual reproduction in ramose broadcasting coral species, which in turn can affect the dominance of the species and the composition and structure of shallow reef environments. [Copyright &y& Elsevier]

This study quantified how the pulse of organic matter from the release of coral gametes triggered a chain of pelagic and benthic processes during an annual mass spawning event on the Australian Great Barrier Reef. Particulate organic matter (POM) concentrations in reef waters increased by threefold to 11-fold the day after spawning and resulted in a stimulation of pelagic oxygen consumption rates that lasted for at least 1 week. Water column microbial communities degraded the organic carbon of gametes of the broadcast-spawning coral Acropora millepora at a rate of >15% h-1, which is about three times faster than the degradation rate measured for larvae of the brooding coral Stylophora pistillata. Stable isotope signatures of POM in the water column reflected the fast transfer of organic matter from coral gametes into higher levels of the food chain, and the amount of POM reaching the seafloor immediately increased after coral spawning and then tailed-off in the next 2 weeks. Short-lasting phytoplankton blooms developed within a few days after the spawning event, indicating a prompt recycling of nutrients released through the degradation of spawning products. These data show the profound effects of coral mass spawning on the reef community and demonstrate the tight recycling of nutrients in this oligotrophic ecosystem. [ABSTRACT FROM AUTHOR]

The rapid decline of Acropora cervicornis and Acropora palmata has often been linked with coral reef deterioration in the Caribbean; yet, it remains controversial whether these species are currently recovering or still declining. In this study, the status of ten populations of A. palmata in Los Roques National Park (LRNP), Venezuela is presented. Six of these populations showed signs of recovery. Ten 80 m2 belt-transects were surveyed at each of the ten reef sites. Within belt-transects, each colony was measured (maximum diameter and height) and its status (healthy, diseased or injured) was recorded. Populations in recovery were deWned by a dominance of small to mediumsized colonies in densities >1 colony per 10 m2, together with 75% undamaged colonies, a low prevalence of diseases (<10%), and a low density of predators (0.25 snails per colony). Based on allozyme analysis of seven polymorphic loci in four populations (N = 30), a moderate to highgenetic connectivity among these populations (FST = 0.048) was found with a predominance of sexual over asexual reproduction (N* : N = 1; Ngo : N = 0.93-1). Both ecological and molecular data support a good prognosis for the recovery of this species in Los Roques. [ABSTRACT FROM AUTHOR]

Dendronephthya gigantea (Verrill, 1864), the dominant species in the waters surrounding Jeju Island, Korea, is a gonochoric internal brooder that releases its planulae from July to September. The ratio of females to males in this azooxanthellate soft coral is 2:1. Oogenesis takes place for 12 months and spermatogenesis for 3–5 months. Gametes mature as seawater temperatures increase, suggesting a seasonal factor in the reproductive cycle. Planulae brooded in the gastrodermal canal were expelled around the times of the full moon and the new moon; a significant difference in numbers expelled was not found between day and night. Ciliated planulae had negative buoyancy after planulation, and showed rapid metamorphosis into a primary polyp stage within 2 days. [ABSTRACT FROM AUTHOR]

Many attempts have been made to recognise divisions within Acropora, the most diverse reef building coral genus on modern reefs, but only subgenera Acropora and Isopora are currently recognised. In this paper, morphological and genetic analyses, and study of reproductive mode and anatomy, demonstrate that an endemic Indonesian species A. (Acropora) togianensis, Wallace, 1997, belongs to Isopora. Despite the presence of a clear central axial corallite (indicating sub-genus Acropora), this species has supplementary axial corallites, broods planula larvae rather than broadcast-spawning for external fertilisation and develops stalked ova: all characters in common with the type species of subgenus Isopora A. (Isopora) palifera and the other species for which such data are available, A. (I.) cuneata and A. (I.) brueggemanni. Phylogenies are based on the protein-coding genes, mitochondrial cytochrome b (cytb) and nuclear histone 2a and 2b (h2ab) also group A. togianensis with these Isoporans. High bootstrapping and Bayesian support in the major lineages of the family Acroporidae demonstrate significant differences between Isopora (including A. togianensis) and Acropora. As the type species of both subgenera, A. (Acropora) muricata (Linneaus 1758) and A. (Isopora) palifera (Lamarck, 1816) are used in these analyses, elevation of Isopora Studer, 1878 to genus is formally proposed. [ABSTRACT FROM AUTHOR]

Many coral reefs worldwide are rapidly declining, but efficient restoration techniques are not yet available. Here, we evaluate methodologies for reef restoration based on the “gardening concept”. A floating mid-water prototype nursery was placed at 6 m depth (14 m above sea-bottom) within the nutrient-enriched environment of a fish farm (Eilat, Red Sea). Ten colonies from five branching coral species provided 6,813 fragments (0.5–3 cm height). The fragments, each attached to a plastic pin, were inserted into plastic nets that were tied to a rope-net floating nursery. After 144 nursery days, only 13.1% of the fragments died and 21.2% were detached by mechanical forces. Small colonies ready for transplantation developed within 144–200 days. Ramets’ ecological volumes increased 13–46 folds and their heights by a factor of 3.5. After 306 days, the ecological volumes of the colonies increased 147–163 fold as compared to original volumes (revealing a daily growth rate constant of 1.67% during the first 5–10 months) and height values by a factor of six. Building and maintenance costs of the nursery were low. This nursery prototype demonstrates the feasibility of the coral “gardening concept” by fulfilling several important needs, namely, mass production of coral colonies at low costs, high survivorship, fast growth, short nursery phase and improved methodologies for handling farmed colonies. [ABSTRACT FROM AUTHOR]

Acropora is the most diverse genus of reef-building corals in the world today. It occurs in all three major oceans; it is restricted to latitudes 31°N–31°S, where most coral reefs occur, and reaches greatest diversity in the central Indo-Pacific. As an exemplar genus, the long-term history of Acropora has implications for the evolution and origins of present day biodiversity patterns of reef corals and for predicting their response to future climate change. Diversification of Acropora was thought to have occurred in the central Indo-Pacific within the previous two million years. We examined Eocene fossils from southern England and northern France and found evidence that precursors of up to nine of 20 currently recognized Acropora species groups existed 49–34Myr, at palaeolatitudes far higher than current limits, to 51°N. We propose that pre-existing diversity contributed to later rapid speciation in this important functional group of corals. [ABSTRACT FROM AUTHOR]

The reproductive biology and its seasonality were examined in the deep-water, solitary coral Fungiacyathus marenzelleri from 2,200 m depth in the NE Atlantic, using histological techniques. A total of 186 corals were collected using either an Otter trawl (semi-balloon) or Agassiz trawl from the research vessel RRS Challenger between 1979 and 1991. All individuals were gonochoric, with all 48 mesenteries being fertile. A high fecundity was recorded (2,892 -44.4 oocytes per polyp) with strong size-dependency. This species is a quasi-continuous reproducer with overlapping gametogenesis for both spermacysts and oocytes. No planulae were observed and broadcasting of gametes is inferred, with the large egg size (max. 750-μm diameter) suggesting lecithotrophic development. There is a non-significant trend towards a synchronous spawning event during June/July. Asexual fission was observed, though in low numbers. [ABSTRACT FROM AUTHOR]

Examines the larval behavior, survivorship competency periods and settlement of brooding corals, Heliopora (H.) coerulea and Pocillopora (P.) damicornis. Factors beneficial for understanding the mechanisms that regulate populations; Larval dispersal patterns of H. coerulea and P. damicornis; Determinant of the distribution of the adult coral population.

[Display omitted] • Targeted DNA capture provide species level resolution in the coral family Fungiidae. • Cryptic speciation reflects geographic isolation and reproductive differences. • Phylogenomics provides an evaluation of species boundaries to aid in coral taxonomy. While the escalating impacts of climate change and other anthropogenic pressures on coral reefs are well documented at the coral community level, studies of species-specific trends are less common, owing mostly to the difficulties and uncertainties in delineating coral species. It has also become clear that traditional coral taxonomy based largely on skeletal macromorphology has underestimated the diversity of many coral families. Here, we use targeted enrichment methods to sequence 2476 ultraconserved elements (UCEs) and exonic loci to investigate the relationship between populations of Fungia fungites from Okinawa, Japan, where this species reproduces by brooding (i.e., internal fertilization), and Papua New Guinea and Australia, where it reproduces by broadcast-spawning (i.e., external fertilization). Moreover, we analyzed the relationships between populations of additional fungiid species (Herpolitha limax and Ctenactis spp.) that reproduce only by broadcast-spawning. Our phylogenetic and species delimitation analyses reveal strong biogeographic structuring in both F. fungites and Herpolitha limax , consistent with cryptic speciation in Okinawa in both species and additionally for H. limax in the Red Sea. By combining UCE/exon data and mitochondrial sequences captured in off-target reads, we reinforce earlier findings that Ctenactis , a genus consisting of three nominal morphospecies, is not a natural group. Our results highlight the need for taxonomic and systematic re-evaluations of some species and genera within the family Fungiidae. This work demonstrates that sequence data generated by the application of targeted capture methods can provide objective criteria by which we can test phylogenetic hypotheses based on morphological and/or life history traits. [ABSTRACT FROM AUTHOR]

As coral reefs continue to degrade globally due to climate change, considerable effort and investment is being put into coral restoration. The production of coral offspring via asexual and sexual reproduction are some of the proposed tools for restoring coral populations and will need to be delivered at scale. Simple, inexpensive, and high-throughput methods are therefore needed for rapid analysis of thousands of coral offspring. Here we develop a machine learning pipeline to rapidly and accurately measure three key indicators of coral juvenile fitness: survival, size, and color. Using machine learning, we classify pixels through an open-source, user-friendly interface to quickly identify and measure coral juveniles on two substrates (field deployed terracotta tiles and experimental, laboratory PVC plastic slides). The method's ease of use and ability to be trained quickly and accurately using small training sets make it suitable for application with images of species of sexually produced corals without existing datasets. Our results show higher accuracy of survival for slides (94.6% accuracy with five training images) compared to field tiles measured over multiple months (March: 77.5%, June: 91.3%, October: 97.9% accuracy with 100 training images). When using fewer training images, accuracy of area measurements was also higher on slides (7.7% average size difference) compared to tiles (24.2% average size difference for October images). The pipeline was 36× faster than manual measurements. The slide images required fewer training images compared to tiles and we provided cut-off guidelines for training for both substrates. These results highlight the importance and power of incorporating high-throughput methods, substrate choice, image quality, and number of training images for measurement accuracy. This study demonstrates the utility of machine learning tools for scalable ecological studies and conservation practices to facilitate rapid management decisions for reef protection. [ABSTRACT FROM AUTHOR]

Presents information on a study of sexuality patterns, modes of reproduction, synchrony and spawning periods of coral Mussismilia in the Abrolhos Reef Complex, Brazil. Importance of reproductive biology of Brazilian coral species; Materials and methods; Results of the study.

Presents a study on the fertilization rate of gorgonian coral in the Caribbean. Materials and methods; Results of study; Discussion.

Determines the relative contributions of sexual and asexual reproduction to recruitment using a hierarchical electrophoretic survey of Seriatopora hystrix on Australia's Great Barrier Reef. Assessment of the apparent scale of larval dispersal; Level of multilocus genotypic diversity; Evidence of recruitment through fragementation.

Presents information on a study which examined the sexual reproduction in the coral of Pocillopora verrucosa (P. verrucosa) in KwaZulu-Natal, South Africa. Methodology of the study; Oocyte development; Fecundity and reproductive activity of P. verrucosa.

Presents a study on the sexual reproduction of the reef-binding coral Montastrea cavernosa in the Santa Marta area, Caribbean coast of Colombia from October 1990 to October 1991. Period of the onset of spermatogenesis; Effect of sea-water temperatures; Gonad index of fully mature female colonies.

Investigates the reproductive isolation among three species of corals, the Montastraea annularis complex from Panama and Honduras. Variation of spawning behavior among the three species; Occurrence of hybridization under natural conditions particularly between M. annularis and M. franski.

The role of autotrophic nutrition in the production of coral planula was investigated in two field experiments carried out in Eilat, the Red Sea during 1980 and 1981, on the branching coral, Stylophora pistillata. Photosynthetically fixed carbon in coral tissue significantly decreased during planulation compared to the non-reproductive season. Planula-larvae collected 1 to 7 mo after coral tissue was labelled with C contained significant amounts of C-labelled photosynthates. The results provide the first direct evidence that energy requirements for planula production in a hermatypic coral are supported by translocation of products from algal photosynthesis. It is suggested that this is also the case in other hermatypic species. [ABSTRACT FROM AUTHOR]

A review is presented of the article "Breakdown in spawning synchrony: A silent threat to coral persistence" by Tom Shlesinger and Yossi Loya comparing coral spawning observations in the Red Sea from data collected from the same reef 30 years prior which found spawning asynchrony was exhibited by three of five species.

Most broadcast spawner corals have a vitellogenic phase that lasts at least 6 months. It is established that estrogen regulates vitellogenin synthesis in vertebrates. Although some research have been conducted on the physiological role of sex steroids in corals, little is known about their involvement in oocyte development. This study aimed to detect steroid hormones – progesterone, testosterone, and estradiol-17β (E2) – in Acropora tenuis and study the relationships between vitellogenesis/vitellogenin synthesis and these steroids. This study also investigated the effect of E2 on vitellogenin synthesis in corals and identified steroidogenic enzymes in A. tenuis genome. Branches from tagged coral colonies were collected monthly from March to November. Histological observations showed that oocytes were vitellogenic from March to May (Stage IV and V), but not in June, and that gonads were occupied by immature oocytes in September (Stage I). Real-time qPCR revealed that vitellogenin (vg1 and vg2) transcript levels in coral branches were high in April and May, implying that corals actively underwent vitellogenesis during these months, and spawned before June. Liquid chromatography-mass spectrometry revealed that E2 could be detected in coral branches in March, April, and May, but not in June, whereas testosterone and progesterone did not fluctuate much in the same months. Immersing branches in E2–containing seawater failed to increase vitellogenin transcript levels. The results indicate that E2 is involved in oogenesis but does not positively regulate vitellogenin synthesis. Steroidogenic enzymes (except CYP19A) were identified in A. tenuis , suggesting that corals may endogenously synthesize progestogens and androgens from cholesterol. [Display omitted] • Three major vertebrate steroid hormones were detected in the scleractinian coral, A. tenuis. • Monthly histological, molecular, and steroid analysis showed a relationship between the presence of E2 and oogenesis. • E2 immersion experiment showed no significant changes in mRNA expression of vitellogenins. • E2 might not be related to vitellogenin synthesis in corals. [ABSTRACT FROM AUTHOR]

Coral reef recovery from major disturbance is hypothesized to depend on the arrival of propagules from nearby undisturbed reefs. Therefore, reefs isolated by distance or current patterns are thought to be highly vulnerable to catastrophic disturbance. We found that on an isolated reef system in north Western Australia, coral cover increased from 9% to 44% within 12 years of a coral bleaching event, despite a 94% reduction in larval supply for 6 years after the bleaching. The initial increase in coral cover was the result of high rates of growth and survival of remnant colonies, followed by a rapid increase in juvenile recruitment as colonies matured. We show that isolated reefs can recover from major disturbance, and that the benefits of their isolation from chronic anthropogenic pressures can outweigh the costs of limited connectivity. [ABSTRACT FROM AUTHOR]

The article reports on a study of the breeding of hermatypic coral Galaxea fascicularis and their partial reproductive isolation between colonies of different nematocyst types and enhancement of fertilization success through parental colonies in Okinawa, Japan. It mixed eggs of hermatypic corals with sperm at an appropriate dilution after successful fertilization. It made 12 standard crosses using gametes from 13 females and nine males wherein very low fertilization were observed in two of the crosses. It also founds out that fertilization experiments of Galaxea fascicularis could be performed in the presence of colony fragments.

Fertilization is a critical life history event and important to population dynamics. Successful fertilization relies on encounters of compatible and viable sperm and eggs. Scleractinian corals that spawn their gametes directly into the water column may experience limitations from sperm dilution and delays in initial sperm-egg encounters that can impact successful fertilization. Notably, the same issues can be experienced when conducting ex situ larval culture. Therefore, experiments were completed using spawned eggs and sperm of the reef corals Acropora tenuis , A. millepora and Favites colemani to determine the optimal ranges of sperm concentrations (<103 to 107 mL−1) and temporal response patterns when crossing of eggs and sperm was delayed (30 min to 10 h). The results showed that sperm concentrations below 103 mL−1 yielded low rates of fertilization for all three species (<30%), but that sperm concentrations at 104 mL−1 resulted in higher rates of fertilization for the Acropora spp. (>65%) and > 90% fertilization rates for F. colemani. Sperm concentrations of 105–107 mL−1 resulted in the highest observed fertilization rates for all three species (>90%). High fertilization rates (>80%) occurred when eggs and sperm were combined after 30 min and up to 2 h after spawning for F. colemani and up to 4 h for A. tenuis and A. millepora gametes. Fertilization rates were significantly reduced (<30%) after a delay of 4 h for F. colemani and after 6 h for the two Acropora species. No fertilization occurred after a 10-h delay in combining gametes for all the tested coral species. Therefore, optimal fertilization success for these coral species rely on sperm densities of ≥104–106 mL−1 and gametes should be combined within two hours after spawning for optimising larval culture. • Fertilization success varies among coral species. • Maximum fertilization can be achieved with concentrations of sperm >104 mL−1. • Combining gametes within the first few hours can result in highest rates of fertilization. • Reduced fertilization success was related to a decreased percentage of viable eggs. [ABSTRACT FROM AUTHOR]

The effects of the xenoestrogen 4-nonylphenol (4NP) on endocrine and metabolic homeostasis in the reef building coral, Pocillopora damicornis were investigated. The aim was to understand if ubiquitous nonylphenol ethoxylate contaminants in the marine environment result in altered homeostatic function. Coral colonies were chronically exposed (6 weeks) to a sublethal concentration (1 ppb) of 4NP and sampled over the coral's lunar reproductive cycle. Although activity of steroidogenic enzymes [cytochrome P450 (CYP) 17, CYP 19, and 3-β-Hydroxysteroid dehydrogenase] and the conjugation enzyme glutathione-S-transferase was not altered, significant increases in the activity of the steroid clearing enzyme UDP-glycosyltransferase (UGT) were observed. The natural fluctuation of UGT activity with the lunar cycle was replaced with consistently high UGT activity throughout the reproductive cycle during 4NP exposure. No effect of 4NP on the reverse reaction, mediated by β-glucuronidase, was observed. Thus, 4NP shifts the UGT:β-glucuronidase ratio toward greater clearance at points in the lunar cycle where retention of compounds is typically favored. Additionally, 4NP reduced activity of the steroid regeneration enzyme steroid sulfatase, further shifting the system toward clearance rather than regeneration. These data imply that environmentally relevant levels of 4NP may be impacting the reproductive health of corals and threatening the persistence of coral reefs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Rougée, Collier and Richmond.)

Successful reproduction and survival are crucial to the continuation and resilience of corals globally. As reef waters warm due to climate change, episodic largescale tropical storms are becoming more frequent, drastically altering the near shore water quality for short periods of time. Therefore, it is critical that we understand the effects warming waters, fresh water input, and run-off have on sexual reproduction of coral. To better understand the effects of these near shore stressors on Hawaiian coral, laboratory experiments were conducted at the Institute of Marine Biology to determine the independent effects of suspended sediment concentrations (100 mg l -1 and 200 mg l -1 ), lowered salinity (28‰), and elevated temperature (31 °C) on the successful fertilization, larval survival, and settlement of the scleractinian coral Montipora capitata. In the present study, early developmental stages of coral were exposed to one of three near shore stressors for a period of 24 h and the immediate (fertilization) and latent effects (larval survival and settlement) were observed and measured. Fertilization success and settlement were not affected by any of the treatments; however, larval survival was negatively affected by all of the treatments by 50% or greater ( p  > 0.05). These data show that early life stages of M. capitata may be impacted by near shore stressors associated with warming and more frequent storm events., Competing Interests: The authors declare there are no competing interests., (©2020 Lager et al.)

The article announces that scientists at the Florida Aquarium's research center have induced Caribbean coral to spawn in a laboratory environment for the first time in history, and it mentions pillar coral research and an effort to conserve near-extinct species and replenish damaged coral reefs.

The article focuses on the study of reproductive segregration of the Red Sea fire coral species, which are dependent on natural selection and ecology. Topics discussed include tropical distribution of Millepora species which are considered gonochoristic, observation of spawning of medusae by three species, and marine benthic organisms.

The article focuses on the sexual maturity of gamete-reared Caribbean Acropora colonies. Topics discussed include the decline of Caribbean coral species population rehabilitation, the attractive method of rearing coral species larvae, and the development of elkhorn coral populations in productive reefs.

Sexual reproduction characteristics of Stylophora pistillata, one of the most common coral species in the Gulf of Eilat, Red Sea, were extensively studied in the 1970s and 1980s. Four decades later, we examined possible changes in reproductive patterns in this species by placing planula traps over S. pistillata colonies during the 2015 and 2016 reproductive seasons. In total, 708 larval traps (222 traps in 2015 and 486 in 2016) were used, collecting 31,396 planulae overall (12,455 in 2015 and 18,852 in 2016). The results of this 2-year study indicated (a) lengthening of the reproductive season by up to 2 months (until mid-September 2015 and August 2016), (b) an extension of peaks in larval release from 2-3 to 5-6 months, (c) an increase in the percentage of colonies that release planula larvae, and (d) a high variability in larval release among different colonies and between consecutive collecting dates. All the above reflect decadal differences in the reproductive effort in S. pistillata. Furthermore, this study reveals that S. pistillata colonies stop releasing planulae after sea surface temperature (SST) reaches its annual peak, contrasting with the earlier finding that planula release ended before the annual SST peak. We propose that global change impacts and an increase in anthropogenic activities in the Gulf of Eilat are the culprit behind the reported changes in coral reproductive traits over the past 4 decades. [ABSTRACT FROM AUTHOR]

Mesophotic coral ecosystems (i.e., deep coral reefs at 30-120 m depth) appear to be thriving while many shallow reefs in the world are declining. Amid efforts to understand and manage their decline, it was suggested that mesophotic reefs might serve as natural refuges and a possible source of propagules for the shallow reefs. However, our knowledge of how reproductive performance of corals alters with depth is sparse. Here, we present a comprehensive study of the reproductive phenology, fecundity, and abundance of seven reef-building conspecific corals in shallow and mesophotic habitats. Significant differences were found in the synchrony and timing of gametogenesis and spawning between shallow and mesophotic coral populations. Thus, mesophotic populations exhibited delayed or protracted spawning events, which led to spawning of the mesophotic colonies in large proportions at times where the shallow ones had long been depleted of reproductive material. All species investigated demonstrated a substantial reduction in fecundity and/or oocyte sizes at mesophotic depths (40-60 m). Two species (Seriatopora hystrix and Galaxea fascicularis) displayed a reduction in both fecundity and oocyte size at mesophotic depths. Turbinaria reniformis had only reduced fecundity and Acropora squarrosa and Acropora valida only reduced oocyte size. In Montipora verrucosa, reduced fecundity was found during one annual reproductive season while, in the following year, only reduced oocyte size was found. In contrast, reduced oocyte size in mesophotic populations of Acropora squarrosa was consistent along three studied years. One species, Acropora pharaonis, was found to be infertile at mesophotic depths along two studied years. This indicates that reproductive performance decreases with depth; and that although some species are capable of reproducing at mesophotic depths, their contribution to the replenishment of shallow reefs may be inconsequential. Reduced reproductive performance with depth, combined with the possible narrower tolerance to environmental factors, further suggests that mesophotic corals may in fact be more vulnerable than previously conceived. Furthermore, we posit that the observed temporal segregation in reproduction could lead to assortative mating, and this, in turn, may facilitate adaptive divergence across depth., (© 2017 by the Ecological Society of America.)