scholarly journals Fish predation hinders the success of coral restoration efforts using fragmented massive corals

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9978 ◽  
Author(s):  
Gammon Koval ◽  
Nicolas Rivas ◽  
Martine D’Alessandro ◽  
Dalton Hesley ◽  
Rolando Santos ◽  
...  

As coral reefs continue to decline globally, coral restoration practitioners have explored various approaches to return coral cover and diversity to decimated reefs. While branching coral species have long been the focus of restoration efforts, the recent development of the microfragmentation coral propagation technique has made it possible to incorporate massive coral species into restoration efforts. Microfragmentation (i.e., the process of cutting large donor colonies into small fragments that grow fast) has yielded promising early results. Still, best practices for outplanting fragmented corals of massive morphologies are continuing to be developed and modified to maximize survivorship. Here, we compared outplant success among four species of massive corals (Orbicella faveolata, Montastraea cavernosa, Pseudodiploria clivosa, and P. strigosa) in Southeast Florida, US. Within the first week following coral deployment, predation impacts by fish on the small (<5 cm2) outplanted colonies resulted in both the complete removal of colonies and significant tissue damage, as evidenced by bite marks. In our study, 8–27% of fragments from four species were removed by fish within one week, with removal rates slowing down over time. Of the corals that remained after one week, over 9% showed signs of fish predation. Our findings showed that predation by corallivorous fish taxa like butterflyfishes (Chaetodontidae), parrotfishes (Scaridae), and damselfishes (Pomacentridae) is a major threat to coral outplants, and that susceptibility varied significantly among coral species and outplanting method. Moreover, we identify factors that reduce predation impacts such as: (1) using cement instead of glue to attach corals, (2) elevating fragments off the substrate, and (3) limiting the amount of skeleton exposed at the time of outplanting. These strategies are essential to maximizing the efficiency of outplanting techniques and enhancing the impact of reef restoration.

2021 ◽  
Author(s):  
Ana M. Palacio-Castro ◽  
Caroline E. Dennison ◽  
Stephanie M. Rosales ◽  
Andrew C. Baker

Coral cover is declining worldwide due to multiple interacting threats. We compared the effects of elevated nutrients and temperature on three Caribbean corals: Acropora cervicornis, Orbicella faveolata, and Siderastrea siderea. Colonies hosting different algal types were exposed to either ambient nutrients (A), elevated NH4 (N), or elevated NH4 + PO4 (N+P) at control temperatures (26 °C) for > 2 months, followed by a 3-week thermal challenge (31.5 °C). A. cervicornis hosted Symbiodinium (S. fitti) and was highly susceptible to the combination of elevated nutrients and temperature. During heat stress, A. cervicornis pre-exposed to elevated nutrients experienced 84%-100% mortality and photochemical efficiency (Fv/Fm) declines of 41-50%. In comparison, no mortality and lower Fv/Fm declines (11-20%) occurred in A. cervicornis that were heat-stressed but not pre-exposed to nutrients. O. faveolata and S. siderea response to heat stress was determined by their algal symbiont community and was not affected by nutrients. O. faveolata predominantly hosted Durusdinium trenchii or Breviolum, but only corals hosting Breviolum were susceptible to heat, experiencing 100% mortality, regardless of nutrient treatment. S. siderea colonies predominantly hosted Cladocopium C1 (C. goreaui), Cladocopium C3, D. trenchii, or variable proportions of Cladocopium C1 and D. trenchii. This species was resilient to elevated nutrients and temperature, with no significant mortality in any of the treatments. However, during heat stress, S. siderea hosting Cladocopium C3 suffered higher reductions in Fv/Fm (41-56%) compared to S. siderea hosting Cladocopium C1 and D. trenchii (17-26% and 10-16%, respectively). These differences in holobiont susceptibility to elevated nutrients and heat may help explain historical declines in A. cervicornis starting decades earlier than other Caribbean corals. Our results suggest that tackling only warming temperatures may be insufficient to ensure the continued persistence of Caribbean corals, especially A. cervicornis. Reducing nutrient inputs to reefs may also be necessary for these iconic coral species to survive.


2021 ◽  
Vol 8 ◽  
Author(s):  
Johanna Calle-Triviño ◽  
Aarón Israel Muñiz-Castillo ◽  
Camilo Cortés-Useche ◽  
Megan Morikawa ◽  
Rita Sellares-Blasco ◽  
...  

Coral restoration has been recognized as an increasingly important tool for coral conservation in recent years. In the Caribbean, the endangered staghorn coral, Acropora cervicornis has been studied for restoration for over two decades with most studies focusing on evaluating simple metrics of success such as colony growth and survivorship in both nurseries and outplanted sites. However, for reef restoration to aid in the recovery of ecological function in outplanted sites, there is a need to measure the functional ecology of the impact of outplanting. Here, we present and identify positive ecological processes and ecological functions (such as increased fish biomass, coral cover, and increased in structural complexity) relative to active reef restoration. In the Southeastern Reefs Marine Sanctuary in the Dominican Republic, we monitored the percentage of benthic cover and fish biomass alongside active reef restoration over the period of 12 months in four zones. Subsequently, we developed multidimensional analyses in conjunction with generalized linear models (GLM) and linear models. Our results show there is a remarkable spatial and temporal differentiation favoring greater ecological function in restored areas. We observed the most noticeable patterns of change in the benthos and coral species composition. We found a positive relationship between amounts of outplanted colonies with the total fish biomass for the three outplanted sites. We highlight that Scarus iseri, a parrotfish critical for grazing maintenance, was the species with the greatest benefit. Our results provide evidence of the functional importance of Acropora cervicornis in coral reef active restoration efforts.


PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1313 ◽  
Author(s):  
Zac H. Forsman ◽  
Christopher A. Page ◽  
Robert J. Toonen ◽  
David Vaughan

Fusion is an important life history strategy for clonal organisms to increase access to shared resources, to compete for space, and to recover from disturbance. For reef building corals, fragmentation and colony fusion are key components of resilience to disturbance. Observations of small fragments spreading tissue and fusing over artificial substrates prompted experiments aimed at further characterizing Atlantic and Pacific corals under various conditions. Small (∼1–3 cm2) fragments from the same colony spaced regularly over ceramic tiles resulted in spreading at rapid rates (e.g., tens of square centimeters per month) followed by isogenic fusion. Using this strategy, we demonstrate growth, in terms of area encrusted and covered by living tissue, ofOrbicella faveolata,Pseudodiploria clivosa, andPorites lobataas high as 63, 48, and 23 cm2per month respectively. We found a relationship between starting and ending size of fragments, with larger fragments growing at a faster rate.Porites lobatashowed significant tank effects on rates of tissue spreading indicating sensitivity to biotic and abiotic factors. The tendency of small coral fragments to encrust and fuse over a variety of surfaces can be exploited for a variety of applications such as coral cultivation, assays for coral growth, and reef restoration.


2021 ◽  
Vol 10 (2) ◽  
pp. 151-161
Author(s):  
Insafitri Insafitri ◽  
Eka Nurahemma Ning Asih ◽  
Wahyu Andy Nugraha

Wisata snorkeling terumbu karang di perairan pulau Gili Labak merupakan salah satu sektor wisata bahari yang sedang dikembangkan oleh pemerintah kebupaten Sumenep Madura sejak tahun 2014 hingga saat ini. Peningkatan jumlah wisatawan yang terjadi pada beberapa tahun terakhir dapat menimbulkan resiko tekanan dan kerusakan ekosistem terumbu karang di area snorkeling secara berkala. Penelitian ini bertujuan untuk mengetahui dampak kegiatan wisatawan sebelum, selama dan sesudah snorkeling terhadap ekosistem terumbu karang yang dikaji dengan mengetahui jenis karang yang mendominasi, status persentase tutupan terumbu karang serta potensi Dampak Wisata Bahari (DWB) snorkeling di lokasi wisata snorkeling pulau Gili Labak Sumenep. Persentase penutupan lifeform karang pulau Gili Labak khususnya di area snorkelling didominasi oleh karang hidup sebanyak 74% dan unsur abiotik sebesar 22%. Jenis karang yang mendominasi pulau Gili Labak adalah Acropora Branching sebesar 19,88% dan Coral Foliose sebesar 10,25%. Selama waktu 6 minggu pengamatan terjadi penurunan total karang sebesar 0,64% yang termasuk kategori rusak ringan, dimana sebagian besar kerusakan terjadi pada karang dengan bentuk pertumbahan branching misalnya Acropora Submassive dan Coral Submassive. Penurunan persen tutupan karang yang tinggi terjadi setelah kegiatan snorkeling (after) yang dilakukan oleh wisatawan. Analisa potensi Dampak Wisata Bahari (DWB) snorkeling pada terumbu karang di perairan Gili Labak selama 6 minggu pengamatan masuk dalam kategori rendah yaitu berkisar 0,052% hingga 0,085%. Faktor penyebab kecilnya nilai presentase Dampak Wisata Bahari (DWB) ini diduga karena waktu pengamatan cenderung pendek dan jenis karang yang mendominasi yaitu Acropora. Acropora memiliki kemampuan regenerasi lebih cepat dibandingkan jenis lainnya.  The snorkeling activity around coral reefs in the waters of Gili Labak is one of the marine tourism sectors that is being developed by the Sumenep Madura district government since 2014. Increasing number of tourists that occurs in recent years pose a risk of pressure and damage to coral reef ecosystems in the snorkeling area. This study aims to determine the impact of tourist activities before, during and after snorkeling on coral reef ecosystems that are studied by knowing the type of dominated coral, the percentage status of coral cover and the potential Impact of snorkeling at the snorkeling sites of the island of Gili Labak Sumenep. The percentage of coral cover in the island of Gili Labak especially in the snorkelling area is dominated by live coral ( 74%) and abiotic elements by 22%. Coral species that dominate the island of Gili Labak are Acropora Branching at 19.88% and Coral Foliose at 10.25%. During the 6-week observation there was a decrease in live coral cover by 0.64% which was categorized as minor damage, most of the damage occurred to branching   Acropora, sub-massive Acropora and Coral Sub-massive. The high percent decrease in coral cover occurred after snorkeling conducted by tourists. Analysis of the potential impact of snorkeling on coral reefs in the waters of Gili Labak for 6 weeks of observation is in the low category, ranging from 0.052% to 0.085%. The factor causing the small impact of Marine Tourism is presumably because the observation time tends to be short and the dominant coral species is Acropora. Acropora has the ability to regenerate faster than other types.


2015 ◽  
Vol 282 (1819) ◽  
pp. 20151887 ◽  
Author(s):  
Verena Schoepf ◽  
Andréa G. Grottoli ◽  
Stephen J. Levas ◽  
Matthew D. Aschaffenburg ◽  
Justin H. Baumann ◽  
...  

Mass bleaching events are predicted to occur annually later this century. Nevertheless, it remains unknown whether corals will be able to recover between annual bleaching events. Using a combined tank and field experiment, we simulated annual bleaching by exposing three Caribbean coral species ( Porites divaricata , Porites astreoides and Orbicella faveolata ) to elevated temperatures for 2.5 weeks in 2 consecutive years. The impact of annual bleaching stress on chlorophyll a , energy reserves, calcification, and tissue C and N isotopes was assessed immediately after the second bleaching and after both short- and long-term recovery on the reef (1.5 and 11 months, respectively). While P. divaricata and O. faveolata were able to recover from repeat bleaching within 1 year, P. astreoides experienced cumulative damage that prevented full recovery within this time frame, suggesting that repeat bleaching had diminished its recovery capacity. Specifically, P. astreoides was not able to recover protein and carbohydrate concentrations. As energy reserves promote bleaching resistance, failure to recover from annual bleaching within 1 year will likely result in the future demise of heat-sensitive coral species.


Coral Reefs ◽  
2021 ◽  
Author(s):  
Derek P. Manzello ◽  
Graham Kolodziej ◽  
Amanda Kirkland ◽  
Nicole Besemer ◽  
Ian C. Enochs

AbstractCoral reefs are globally in decline and western Atlantic reefs have experienced the greatest losses in live coral cover of any region. The Flower Garden Banks (FGB) in the Gulf of Mexico are high-latitude, remote reefs that are an outlier to this trend, as they have maintained coral cover ≥ 50% since at least 1989. Quantifying the long-term trends in coral growth of key reef-building coral species, and the underlying environmental drivers, leads to a better understanding of local sensitivities to past changes that will ultimately allow us to better predict the future of reef growth at FGB. We obtained coral cores and constructed growth records for two of the most abundant hermatypic coral species at FGB, Pseudodiploria strigosa and Orbicella faveolata. Our records cover 57 yrs of growth for P. strigosa (1957–2013) and 45 yrs for O. faveolata (1970–2014). Linear extension and calcification rates of both species have increased significantly, but skeletal density did not change over the respective time periods. Extension and calcification data of both species combined were negatively correlated with the discharge from the Atchafalaya River, but positively correlated with maximum sea surface temperatures (SST). These data provide evidence that runoff from the Atchafalaya River impacts FGB corals and is a major control on coral growth at FGB. The increase in growth at FGB can be attributed to the significant warming trend in maximum monthly SSTs. Given the warming trend and recent increase in severity of bleaching at FGB, the prognosis is that bleaching events will become more deleterious with time, which will lead to a breakdown in the positive relationship between coral growth and maximum SST. This study provides further evidence that some high-latitude, cooler reef sites have experienced a stimulation in coral growth with ocean warming.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2196 ◽  
Author(s):  
Alejandra Verde ◽  
Carolina Bastidas ◽  
Aldo Croquer

Caribbean ciliate infection (CCI) and white band disease (WBD) are diseases that affect a multitude of coral hosts and are associated with rapid rates of tissue losses, thus contributing to declining coral cover in Caribbean reefs. In this study we compared tissue mortality rates associated to CCI in three species of corals with different growth forms:Orbicella faveolata(massive-boulder),O. annularis(massive-columnar) andAcropora cervicornis(branching). We also compared mortality rates in colonies ofA. cervicornisbearing WBD and CCI. The study was conducted at two locations in Los Roques Archipelago National Park between April 2012 and March 2013. InA. cervicornis, the rate of tissue loss was similar between WBD (0.8 ± 1 mm/day, mean ± SD) and CCI (0.7 ± 0.9 mm/day). However, mortality rate by CCI inA. cervicorniswas faster than in the massive speciesO. faveolata(0.5 ± 0.6 mm/day) andO. annularis(0.3 ± 0.3 mm/day). Tissue regeneration was at least fifteen times slower than the mortality rates for both diseases regardless of coral species. This is the first study providing coral tissue mortality and regeneration rates associated to CCI in colonies with massive morphologies, and it highlights the risks of further cover losses of the three most important reef-building species in the Caribbean.


2016 ◽  
Vol 19 (2) ◽  
pp. 059
Author(s):  
Amin Bagheri ◽  
Ahmad Masoumi ◽  
Jamshid Bagheri

<strong>Background:</strong> Coronary endarterectomy (CE) is performed as an adjunct to coronary artery bypass surgery (CABG); however, the efficacy of this technique is still controversial. We aimed to evaluate the impact of CE combined with CABG when compared with isolated CABG.<br /><strong>Methods:</strong> Patients who underwent CABG between July 2007 and June 2014 were included. 70 of 2452 patients (2.8%) underwent CE in addition to CABG. Early results were compared with isolated CABG and predictors of adverse outcome were measured in stepwise multivariate logistic regression analyses.<br /><strong>Results:</strong> The incidence of comorbidities including prior myocardial infarction, diabetes mellitus, and three-vessel coronary disease in CE patients was higher; however, mortality (4.3% versus control 3.6%; P = .762) and postoperative complications were not significantly increased in this group of patients (except supraventricular arrhythmia). Although age greater than 70 years, impaired ejection fraction, intraoperative intraaortic balloon pump, and prolonged cardiopulmonary bypass time were important predictors of adverse outcomes, CE was not associated with increased mortality or postoperative morbidities. <br /><strong>Conclusion:</strong> Despite the higher risk profile of patients who underwent CE, this technique was not identified as an independent risk factor for adverse postoperative outcomes.


Hydrobiologia ◽  
2021 ◽  
Author(s):  
L. Saponari ◽  
I. Dehnert ◽  
P. Galli ◽  
S. Montano

AbstractCorallivory causes considerable damage to coral reefs and can exacerbate other disturbances. Among coral predators, Drupella spp. are considered as delayer of coral recovery in the Republic of Maldives, although little information is available on their ecology. Thus, we aimed to assess their population structure, feeding behaviour and spatial distribution around 2 years after a coral bleaching event in 2016. Biological and environmental data were collected using belt and line intercept transects in six shallow reefs in Maldives. The snails occurred in aggregations with a maximum of 62 individuals and exhibited a preference for branching corals. Yet, the gastropods showed a high plasticity in adapting feeding preferences to prey availability. Drupella spp. were homogenously distributed in the study area with an average of 9.04 ± 19.72 ind/200 m2. However, their occurrence was significantly different at the reef scale with the highest densities found in locations with higher coral cover. The impact of Drupella spp. appeared to be minimal with the population suffering from the loss of coral cover. We suggest that monitoring programs collect temporal- and spatial-scale data on non-outbreaking populations or non-aggregating populations to understand the dynamics of predation related to the co-occurrence of anthropogenic and natural impacts.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Zhen Shi ◽  
Shijiong Qin ◽  
Yung-ho Chiu ◽  
Xiaoying Tan ◽  
Xiaoli Miao

AbstractChina’s commercial banks have developed at a very rapid speed in recent decades. However, with global economic development slowing down, the impact of gross domestic product growth as an exogenous factor cannot be ignored. Most existing studies only consider the internal factors of banks, and neglect their external economic factors. This study thus adopts an undesirable dynamic slacks-based measure under an exogenous model in combination with the Kernel density curve to explore the efficiency of state-owned commercial banks (SOCBs), joint-stock commercial banks (JSCBs), and urban commercial banks (UCBs) in China from 2012 to 2018. The results show that SOCBs have the highest overall efficiency, followed by JSCBs, then UCBs. The efficiencies of SOCBs, JSCBs, and UCBs in the financing stage are greater than those in the investment stage, indicating that the latter stage brings down overall efficiency. Thus, all commercial banks need to focus on the efficiency of non-performing loans and return on capital. Finally, SOCBs need to strengthen internal controls, reduce non-performing loans and improve return on capital. JSCBs should actively expand its business while controlling costs, and UCBs should optimize its management.


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