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Coral bleaching, a consequence of stressed symbiotic relationships between corals and algae, has escalated due to intensified heat stress events driven by climate change. Despite global efforts, current early warning systems lack local precision. Our study, spanning 2015–2017 in the Mesoamerican Reef, revealed prevalent intermediate bleaching, peaking in 2017. By scrutinizing 23 stress exposure and sensitivity metrics, we accurately predicted 75% of bleaching severity variation. Notably, distinct thermal patterns—particularly the climatological seasonal warming rate and various heat stress metrics—emerged as better predictors compared to conventional indices (such as Degree Heating Weeks). Surprisingly, deeper reefs with diverse coral communities showed heightened vulnerability. This study presents a framework for coral reef bleaching vulnerability assessment, leveraging accessible data (including historical and real-time sea surface temperature, habitat variables, and species composition). Its operational potential lies in seamless integration with existing monitoring systems, offering crucial insights for conservation and management. A study on the Mesoamerican Reef shows that the climatological rate of seasonal warming and heat stress metrics more accurately predict coral bleaching severity than conventional indices, enhancing regional early warning systems for better conservation strategies. [ABSTRACT FROM AUTHOR]

Mapping the economic value of the ocean is pivotal to understand how marine ecosystems contribute to human well-being and to support fisheries management. We present a framework to analyse fisheries data and map fishing revenues by linking Vessel Monitoring System (VMS) information to logbooks and observer data. We provide a detailed step-by-step methodology and describe different approaches available to fulfill each step, with special notes for the processing of real-world messy data. The framework consists of six processing steps: (1) identifying the target fishery and subsetting VMS data, (2) extracting relevant variables, (3) linking observer and VMS data, (4) identifying fishing activity, (5) linking VMS and logbook data, and (6) extracting derived variables and mapping revenue back to the communities that extracted the resources. Building this framework opens a broad range of applications including marine spatial planning, rapid response analyses, high-resolution stock assessments, and spatially explicit-socioeconomic analyses. We demonstrate the framework in the reef fishery of the Gulf of Mexico, where spatial planning for aquaculture is currently underway. [ABSTRACT FROM AUTHOR]

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

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

Identifying relatively intact areas within ecosystems and determining the conditions favoring their existence is necessary for effective management in the context of widespread environmental degradation. In this study, we used 3766 surveys of randomly selected sites in the United States and U.S. Territories to identify the correlates of sites categorized as "oases" (defined as sites with relatively high total coral cover). We used occupancy models to evaluate the influence of 10 environmental predictors on the probability that an area (21.2‐km2 cell) would harbor coral oases defined at four spatial extents: cross‐basin, basin, region, and subregion. Across all four spatial extents, oases were more likely to occur in habitats with high light attenuation. The influence of the other environmental predictors on the probability of oasis occurrence were less consistent and varied with the scale of observation. Oases were most likely in areas of low human population density, but this effect was evident only at the cross‐basin and subregional extents. At the regional and subregional extents oases were more likely where sea‐surface temperature was more variable, whereas at the larger spatial extents the opposite was true. By identifying the correlates of oasis occurrence, the model can inform the prioritization of reef areas for management. Areas with biophysical conditions that confer corals with physiological resilience, as well as limited human impacts, likely support coral reef oases across spatial extents. Our approach is widely applicable to the development of conservation strategies to protect biodiversity and ecosystems in an era of magnified human disturbance. [ABSTRACT FROM AUTHOR]

In the search for protecting biodiversity, enhancing sustainable resource use, and minimizing conflict among users, spatial planning is now ubiquitous around the globe. Acquiring maps of fishing activity is critical to account for the interests of fishers, but fisheries are generally underrepresented in spatial plans. We conducted a quantitative systematic literature review on how fisheries data have been included in spatial planning. 145 research articles were reviewed. Most studies (99%) assessed marine ecosystems. A kaleidoscope of data sources has been used to map fisheries, from vessel tracking data (11%) to surrogates (17%). Most articles (43%) have focused on mapping fishing effort, but other variables might be more relevant for spatial planning. Stakeholder groups are generally aggregated together (84%), but to achieve socially equitable outcomes, differences in relative importance or vulnerability should be included in the analyses. There ought to be a shift in spatial and temporal scale so that the scale in which fishing activity is recorded matches the scales needed for relevant management. At the planning stage, fishing data have been incorporated mostly to avoid conflict (97%). However, when stocks are overfished, ensuring some areas remain open to fishing and including fisheries in alternative ways to "cost" (which incorporates the economic and social impact of spatial closures) might be necessary. The use of inappropriate fisheries data has produced spatial plans that lead to poor management decisions, social conflict, and lack of compliance. Based on these results, we offer a set of suggestions on how to develop fisheries spatial planning research that will promote environmental and social sustainability. [ABSTRACT FROM AUTHOR]

Climate change has become the greatest threat to the world's ecosystems. Locating and managing areas that contribute to the survival of key species under climate change is critical for the persistence of ecosystems in the future. Here, we identify 'Climate Priority' sites as coral reefs exposed to relatively low levels of climate stress that will be more likely to persist in the future. We present the first analysis of uncertainty in climate change scenarios and models, along with multiple objectives, in a marine spatial planning exercise and offer a comprehensive approach to incorporating uncertainty and trade‐offs in any ecosystem. We first described each site using environmental characteristics that are associated with a higher chance of persistence (larval connectivity, hurricane influence, and acute and chronic temperature conditions in the past and the future). Future temperature increases were assessed using downscaled data under four different climate scenarios (SSP1 2.6, SSP2 4.5, SSP3 7.0 and SSP5 8.5) and 57 model runs. We then prioritized sites for intervention (conservation, improved management or restoration) using robust decision‐making approaches that select sites that will have a benign climate under most climate scenarios and models. The modelling work is novel because it solves two important issues. (1) It considers trade‐offs between multiple planning objectives explicitly through Pareto analyses and (2) It makes use of all the uncertainty around future climate change. Priority intervention sites identified by the model were verified and refined through local stakeholder engagement including assessments of local threats, ecological conditions and government priorities. The workflow is presented for the Insular Caribbean and Florida, and at the national level for Cuba, Jamaica, Dominican Republic and Haiti. Our approach allows managers to consider uncertainty and multiple objectives for climate‐smart spatial management in coral reefs or any ecosystem across the globe. [ABSTRACT FROM AUTHOR]

There is a widespread need for reliable biodiversity databases for science and conservation. Among the many public databases available, we lack guidance as to how their data quality varies. Here, we compare species distribution data for a well known regional reef fish fauna extracted from five global online databases that supply "as is" data (GBIF, OBIS, IDigBio, FishNet2 and FishBase) and our own curated regional database (STRI, Smithsonian Tropical Research Institute) using quantitative criteria, and assess how they affect biogeographical analyses. We first describe the databases and quantify overlap between them. We then describe variation in the geographical distributions of species records and species richness and in the completeness of local species lists. Finally, we assess the consequences of using these different databases in biogeographical analyses by comparing patterns of species turnover (beta diversity) and bioregionalization. The databases vary considerably in size and show high overlap in species lists, but low overlap in georeferenced species records. Levels of completeness of local inventories are spatially heterogeneous and low in most databases. Spatial biases produced artefactual variation in patterns of species turnover and delineation of bioregions in all databases. Although not the largest, STRI database has the most complete geographic coverage of data, showed relatively low turnover and the clearest biogeographic regionality. Incorporating data from a wide range of other sources, curating data to reduce errors, and assessing effects of spatial biases in data is critical to obtaining an accurate picture of the geography of biodiversity and its change. [ABSTRACT FROM AUTHOR]

Anthropogenic environmental change has increased coral reef disturbance regimes in recent decades, altering the structure and function of many coral reefs globally. In this study, we used coral community survey data collected from 1996 to 2015 to evaluate reef-scale coral calcification capacity (CCC) dynamics with respect to recorded pulse disturbances for 121 reef sites in the Main Hawaiian Islands and Mo'orea (French Polynesia) in the Pacific and the Florida Keys Reef Tract and St. John (U.S. Virgin Islands) in the western Atlantic. CCC remained relatively high in the Main Hawaiian Islands in the absence of recorded widespread disturbances; declined and subsequently recovered in Mo'orea following a crown-ofthorns sea star outbreak, coral bleaching, and major cyclone; decreased and remained low following coral bleaching in the Florida Keys Reef Tract; and decreased following coral bleaching and disease in St. John. Individual coral taxa have variable calcification rates and susceptibility to disturbances because of their differing life-history strategies. As a result, temporal changes in CCC in this study were driven by shifts in both overall coral cover and coral community composition. Analysis of our results considering coral lifehistory strategies showed that weedy corals generally increased their contributions to CCC over time while the contribution of competitive corals decreased. Shifts in contributions by stress-tolerant and generalist corals to CCC were more variable across regions. The increasing frequency and intensity of disturbances under 21st century global change therefore has the potential to drive lower and more variable CCC because of the increasing dominance of weedy and some stress-tolerant corals. [ABSTRACT FROM AUTHOR]

Effective management of social-ecological systems (SESs) requires an understanding of human behavior. In many SESs, there are hundreds of agents or more interacting with governance and regulatory institutions, driving management outcomes through collective behavior. Agents in these systems often display consistent behavioral characteristics over time that can help reduce the dimensionality of SES data by enabling the assignment of types. Typologies of resource-user behavior both enrich our knowledge of user cultures and provide critical information for management. Here, we develop a data-driven framework to identify resource-user typologies in SESs with high-dimensional data. To demonstrate policy applications, we apply the framework to a tightly coupled SES, commercial fishing. We leverage large fisheries-dependent datasets that include mandatory vessel logbooks, observer datasets, and high-resolution geospatial vessel tracking technologies. We first quantify vessel and behavioral characteristics using data that encode fishers’ spatial decisions and behaviors. We then use clustering to classify these characteristics into discrete fishing behavioral types (FBTs), determining that 3 types emerge in our case study. Finally, we investigate how a series of disturbances applied selection pressure on these FBTs, causing the disproportionate loss of one group. Our framework not only provides an efficient and unbiased method for identifying FBTs in near real time, but it can also improve management outcomes by enabling ex ante investigation of the consequences of disturbances such as policy actions. [ABSTRACT FROM AUTHOR]

Human activities have led to widespread ecological decline; however, the severity of degradation is spatially heterogeneous due to some locations resisting, escaping, or rebounding from disturbances.We developed a framework for identifying oases within coral reef regions using long‐term monitoring data. We calculated standardised estimates of coral cover (z‐scores) to distinguish sites that deviated positively from regional means. We also used the coefficient of variation (CV) of coral cover to quantify how oases varied temporally, and to distinguish among types of oases. We estimated "coral calcification capacity" (CCC), a measure of the coral community's ability to produce calcium carbonate structures and tested for an association between this metric and z‐scores of coral cover.We illustrated our z‐score approach within a modelling framework by extracting z‐scores and CVs from simulated data based on four generalized trajectories of coral cover. We then applied the approach to time‐series data from long‐term reef monitoring programmes in four focal regions in the Pacific (the main Hawaiian Islands and Mo'orea, French Polynesia) and western Atlantic (the Florida Keys and St. John, US Virgin Islands). Among the 123 sites analysed, 38 had positive z‐scores for median coral cover and were categorised as oases.Synthesis and applications. Our framework provides ecosystem managers with a valuable tool for conservation by identifying "oases" within degraded areas. By evaluating trajectories of change in state (e.g., coral cover) among oases, our approach may help in identifying the mechanisms responsible for spatial variability in ecosystem condition. Increased mechanistic understanding can guide whether management of a particular location should emphasise protection, mitigation or restoration. Analysis of the empirical data suggest that the majority of our coral reef oases originated by either escaping or resisting disturbances, although some sites showed a high capacity for recovery, while others were candidates for restoration. Finally, our measure of reef condition (i.e., median z‐scores of coral cover) correlated positively with coral calcification capacity suggesting that our approach identified oases that are also exceptional for one critical component of ecological function. Our framework provides ecosystem managers with a valuable tool for conservation by identifying "oases" within degraded areas. By evaluating trajectories of change in state (e.g., coral cover) among oases, our approach may help in identifying the mechanisms responsible for spatial variability in ecosystem condition. Increased mechanistic understanding can guide whether management of a particular location should emphasise protection, mitigation or restoration. Analysis of the empirical data suggest that the majority of our coral reef oases originated by either escaping or resisting disturbances, although some sites showed a high capacity for recovery, while others were candidates for restoration. Finally, our measure of reef condition (i.e., median z‐scores of coral cover) correlated positively with coral calcification capacity suggesting that our approach identified oases that are also exceptional for one critical component of ecological function. [ABSTRACT FROM AUTHOR]

Coastal ecosystems and the livelihoods they support are threatened by stressors acting at global and local scales. Here we used the data produced by the Caribbean Coastal Marine Productivity program (CARICOMP), the longest, largest monitoring program in the wider Caribbean, to evidence local-scale (decreases in water quality) and global-scale (increases in temperature) stressors across the basin. Trend analyses showed that visibility decreased at 42% of the stations, indicating that local-scale chronic stressors are widespread. On the other hand, only 18% of the stations showed increases in water temperature that would be expected from global warming, partially reflecting the limits in detecting trends due to inherent natural variability of temperature data. Decreases in visibility were associated with increased human density. However, this link can be decoupled by environmental factors, with conditions that increase the flush of water, dampening the effects of human influence. Besides documenting environmental stressors throughout the basin, our results can be used to inform future monitoring programs, if the desire is to identify stations that provide early warning signals of anthropogenic impacts. All CARICOMP environmental data are now available, providing an invaluable baseline that can be used to strengthen research, conservation, and management of coastal ecosystems in the Caribbean basin. [ABSTRACT FROM AUTHOR]

The Mesoamerican Reef (MAR) is an interconnected system that supports the local economies of four countries through the provision of seafood and tourism. Considerable financial, research and management effort has been invested in this priority ecoregion, whose boundaries were defined more than 18 yr ago based on best available data on oceanographic patterns, reef and watershed distribution. The long-term persistence of the MAR depends, however, on ensuring that all of its constituent parts are appropriately managed, and the current boundaries may not respond to this need. Here we assess the suitability of the current boundaries of the MAR using information on physical environments and larval connectivity of three key species. Our research indicates the boundaries of the ecoregion require an adjustment, as the exclusion of key areas in eastern Honduras might jeopardize the persistence of the entire network of connected reefs, and areas in northern Yucatan belong to a different environmental regime and may require different management strategies. [ABSTRACT FROM AUTHOR]

To support fishing communities, reserves should ensure the persistence of meta-populations while boosting fisheries yield. However, so far their design from the onset has rarely considered both objectives simultaneously. Here we overcome this barrier in designing a network of reserves for the Caribbean spiny lobster, a species with long larval duration for which local management is considered pointless because the benefits of protection are believed to be accrued elsewhere. Our reserve design approach uses spatially explicit population models and considers ontogenetic migration, larval and adult movement. We show that yield and persistence are negatively related, but that both objectives can be maximized simultaneously during planning. Importantly, we also show that local efforts to manage spiny lobster, the most economically valuable marine resource in the Caribbean, can result in locally accrued benefits, overcoming a major barrier to investing effort in the appropriate management of this species. [ABSTRACT FROM AUTHOR]

While environmental filters are well-known factors influencing community assembly, the extent to which these modify species functions, and entire ecosystem processes, is poorly understood., Focusing on a high-diversity system, we ask whether environmental filtering has ecosystem-wide effects beyond community assembly. We characterise a coral reef herbivorous fish community for swimming performance based on ten functional traits derived from fish morphology. We then investigate whether wave exposure modifies the functional make-up of herbivory, and the absolute and relative feeding frequency of distinct feeding functional groups., Herbivorous fish species conformed to either laterally compressed or fusiform body plans, which differ in their morphological design to minimise drag. High wave exposure selectively limited the feeding function of the deepest body shapes with highest caudal thrust efficiency, and favoured fusiform bodies irrespective of pectoral fin shape., Traditionally recognised herbivore feeding functional groups (i.e. grazers-detritivores and scrapers-small excavators) differed in swimming performance, and in their capacity to feed consistently across levels of wave exposure. We therefore emphasise the distinctness of their ecological niche and functional complementarity., Species within the same feeding functional group also had contrasting responses to wave exposure. We thereby reveal a further ecological dimension of niche partitioning, and reiterate the risk of assuming functional redundancy among species with a common feeding mode., Contrasting responses of species within feeding functional roles (i.e. response diversity) allowed the preservation of critical trophic functions throughout the gradient (e.g. macroalgal browsing), and likely explained why overall levels of herbivory were robust to filtering. Whether ecosystem functioning will remain robust under the additive effects of environmental stress and human-induced disturbances remains to be tested., A is available for this article. [ABSTRACT FROM AUTHOR]

Big data, such as vessel monitoring system (VMS) data, can provide valuable information on fishing behaviours. However, conventional methods of detecting behaviours in movement data are challenged when behaviours are briefer than signal resolution. We investigate options for improving detection accuracy for short-set fisheries using 581 648 position records from 181 vessels in the Gulf of Mexico bandit-reel fishery. We first investigate the effects of increasing VMS temporal resolution and find that detection accuracy improves with fishing-set duration. We then assess whether a feature engineering approach—in our case, changing the way pings are labelled when training a classifier—could improve detection accuracy. From a dataset of 12 184 observed sets, we find that the conventional point-labelling method results in only 49% of pings being correctly labelled as ‘fishing’, whereas a novel window-labelling method results in 88% of records being labelled as ‘fishing’. When the labelled data are used to train classifiers, point labelling attains true-positive/balanced-accuracy rates of only 37%/66%, whereas window labelling achieves 68%/83%. Finally, we map fishing distribution using the two methods, and show that point labelling underestimates the extent of fishing grounds by ~33%, highlighting the benefits of window labelling in particular, and feature engineering approaches in general. [ABSTRACT FROM AUTHOR]

The physiological performance of a reef-building coral is a combined outcome of both the coral host and its algal endosymbionts, Symbiodinium. While Orbicella annularis--a dominant reef-building coral in the Wider Caribbean-- is known to be a flexible host in terms of the diversity of Symbiodinium types it can associate with, it is uncertain how this diversity varies across the Caribbean, and whether spatial variability in the symbiont community is related to either O. annularis genotype or environment. Here, we target the Symbiodinium-ITS2 gene to characterize and map dominant Symbiodinium hosted by O. annularis at an unprecedented spatial scale. We reveal northwest-southeast partitioning across the Caribbean, both in terms of the dominant symbiont taxa hosted and in assemblage diversity. Multivariate regression analyses incorporating a suite of environmental and genetic factors reveal that observed spatial patterns are predominantly explained by chronic thermal stress (summer temperatures) and are unrelated to host genotype. Furthermore, we were able to associate the presence of specific Symbiodinium types with local environmental drivers (for example, Symbiodinium C7 with areas experiencing cooler summers, B1j with nutrient loading and B17 with turbidity), associations that have not previously been described. [ABSTRACT FROM AUTHOR]

Disturbance releases space and allows the growth of opportunistic species, excluded by the old stands, with a potential to alter community dynamics. In coral reefs, abundances of fast-growing, and disturbance-tolerant sponges are expected to increase and dominate as space becomes available following acute coral mortality events. Yet, an increase in abundance of these opportunistic species has been reported in only a few studies, suggesting certain mechanisms may be acting to regulate sponge populations. To gain insights into mechanisms of population control, we simulated the dynamics of the common reef-excavating sponge Cliona tenuis in the Caribbean using an individual-based model. An orthogonal hypothesis testing approach was used, where four candidate mechanisms-algal competition, stock-recruitment limitation, whole and partial mortality-were incorporated sequentially into the model and the results were tested against independent field observations taken over a decade in Belize, Central America. We found that releasing space after coral mortality can promote C. tenuis outbreaks, but such outbreaks can be curtailed by macroalgal competition. The asymmetrical competitive superiority of macroalgae, given by their capacity to pre-empt space and outcompete with the sponge in a size-dependant fashion, supports their capacity to steal the opportunity from other opportunists. While multiple system stages can be expected in coral reefs following intense perturbation macroalgae may prevent the growth of other space-occupiers, such as bioeroding sponges, under low grazing pressure. [ABSTRACT FROM AUTHOR]

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

Coral reefs are in decline worldwide and monitoring activities are important for assessing the impact of disturbance on reefs and tracking subsequent recovery or decline. Monitoring by field surveys provides accurate data but at highly localised scales and so is not cost-effective for reef scale monitoring at frequent time points. Remote sensing from satellites is an alternative and complementary approach. While remote sensing cannot provide the level of detail and accuracy at a single point than a field survey, the statistical power for inferring large scale patterns benefits in having complete areal coverage. This review considers the state of the art of coral reef remote sensing for the diverse range of objectives relevant for management, ranging from the composition of the reef: physical extent, benthic cover, bathymetry, rugosity; to environmental parameters: sea surface temperature, exposure, light, carbonate chemistry. In addition to updating previous reviews, here we also consider the capability to go beyond basic maps of habitats or environmental variables, to discuss concepts highly relevant to stakeholders, policy makers and public communication: such as biodiversity, environmental threat and ecosystem services. A clear conclusion of the review is that advances in both sensor technology and processing algorithms continue to drive forward remote sensing capability for coral reef mapping, particularly with respect to spatial resolution of maps, and synthesis across multiple data products. Both trends can be expected to continue. [ABSTRACT FROM AUTHOR]

Environmental conditions play an important role in post-disturbance dynamics of ecosystems by modulating recovery of surviving communities and influencing patterns of succession. Here, we document the effects of wave exposure following a catastrophic disturbance on coral reefs in driving a phase shift to macroalgal dominance. In December 2012, a Category 5 super typhoon ('Typhoon Bopha') passed 50 km to the south of Palau (Micronesia), causing a major loss of reef corals. Immediately post-disturbance, a rapid and extensive phase shift of the macroalgae Liagora sp. (Rhodophyta) was observed at sites exposed to chronic wave exposure. To quantify the influence of biotic and abiotic drivers in modulating the extent of post-disturbance Liagora blooms, we compared benthic substrates and herbivore assemblages at sites surveyed pre- and post-disturbance across a gradient of wave exposure. Relative changes in herbivore biomass and coral cover before and after disturbance did not significantly predict the extent of Liagora cover, indicating that changes in herbivore biomass or reductions in grazing pressure were not directly responsible for driving the Liagora blooms. By contrast, the degree of wave exposure experienced at sites post-disturbance explained >90 % of model variance ( p < 0.001, R = 0.69), in that Liagora was absent at low exposure sites, while most extensive blooms were observed at highly exposed sites. At regional scales, spatial maps of wave exposure accurately predicted the presence of Liagora at impacted sites throughout the Palau archipelago (>150 km distance), highlighting the predictive capacity of wave exposure as an explanatory variable and the deterministic nature of post-disturbance macroalgal blooms. Understanding how physical conditions modulate recovery of ecosystems after disturbance allows insight into post-disturbance dynamics and succession of communities, ultimately allowing management strategies to prioritise restoration efforts in regions that are most effective. [ABSTRACT FROM AUTHOR]

Aim Coral assemblages on Caribbean reefs have largely been considered to be biogeographically homogeneous at a regional scale. We reassess this in three taxa (corals, sponges and octocorals) using three community attributes with increasing levels of information (species richness, composition and relative abundance) across hierarchical spatial scales, and identify the key environmental drivers associated with this variation. Location Caribbean Basin. Methods We assessed reefs along 546 transects positioned within the same forereef habitat ( Orbicella reef) in 11 countries, using a consistent methodology and surveyors. Spatial variability in richness, composition and relative abundance was assessed at four hierarchical spatial scales - transects (metres), sites (kilometres), areas (tens of kilometres) and regions (hundreds of kilometres) - using permutational multivariate analysis of variance ( PERMANOVA). The relevance of contemporary environmental factors in explaining the observed spatial patterns was also assessed using PERMANOVA. Results Consistent with previous studies, species richness of coral assemblages, commonly the focus of biogeographical studies, showed little variance at large spatial scales. In contrast, species composition and relative abundance showed significant variability at regional scales. Coral, sponge and octocoral assemblages each varied independently across spatial scales. Rugosity and wave exposure were key drivers of the composition and relative abundance of coral and octocoral assemblages. Main conclusions Caribbean reef assemblages exhibit considerable biogeographical variability at broad spatial scales (hundreds of kilometres) when more responsive community attributes were used. However, the high degree of variability within sites (kilometres) highlights the relevance of local ecological drivers such as rugosity and wave exposure in structuring assemblages. The high levels of within-site variability that is not explained by environmental variables may suggest a previously unrealized contribution of anthropogenic disturbance operating at local scales throughout the region. [ABSTRACT FROM AUTHOR]

Under projections of global climate change and other stressors, significant changes in the ecology, structure and function of coral reefs are predicted. Current management strategies tend to look to the past to set goals, focusing on halting declines and restoring baseline conditions. Here, we explore a complementary approach to decision making that is based on the anticipation of future changes in ecosystem state, function and services. Reviewing the existing literature and utilizing a scenario planning approach, we explore how the structure of coral reef communities might change in the future in response to global climate change and overfishing. We incorporate uncertainties in our predictions by considering heterogeneity in reef types in relation to structural complexity and primary productivity. We examine 14 ecosystem services provided by reefs, and rate their sensitivity to a range of future scenarios and management options. Our predictions suggest that the efficacy of management is highly dependent on biophysical characteristics and reef state. Reserves are currently widely used and are predicted to remain effective for reefs with high structural complexity. However, when complexity is lost, maximizing service provision requires a broader portfolio of management approaches, including the provision of artificial complexity, coral restoration, fish aggregation devices and herbivore management. Increased use of such management tools will require capacity building and technique refinement and we therefore conclude that diversification of our management toolbox should be considered urgently to prepare for the challenges of managing reefs into the 21st century. [ABSTRACT FROM AUTHOR]

Reef managers cannot fight global warming through mitigation at local scale, but they can use information on thermal patterns to plan for reserve networks that maximize the probability of persistence of their reef system. Here we assess previous methods for the design of reserves for climate change and present a new approach to prioritize areas for conservation that leverages the most desirable properties of previous approaches. The new method moves the science of reserve design for climate change a step forwards by: (1) recognizing the role of seasonal acclimation in increasing the limits of environmental tolerance of corals and ameliorating the bleaching response; (2) using the best proxy for acclimatization currently available; (3) including information from several bleaching events, which frequency is likely to increase in the future; (4) assessing relevant variability at country scales, where most management plans are carried out. We demonstrate the method in Honduras, where a reassessment of the marine spatial plan is in progress. [ABSTRACT FROM AUTHOR]

Ecosystem management frequently aims to manage resilience yet measuring resilience has proven difficult. Here, we quantify the ecological resilience of the largest reef in the Caribbean and map potential benefits of marine reserves under two scenarios of greenhouse gas emissions. Resilience is calculated using spatial ecological models and defined as the probability of a reef remaining in its coral-dominated basin of attraction such that it does not flip into an alternate, algal-dominated attractor. In practice, resilience is the probability that coral populations will maintain the ability to exhibit a recovery trend after acute disturbances such as hurricanes. The inputs required to estimate resilience are a reef's initial state, physical environment, and disturbance regime. One major driver of reef resilience is herbivory by parrotfish and recent action to protect parrotfish in Belize was found to have increased resilience 6-fold. However, the expected benefits of parrotfish protection to future coral cover were relatively modest with only a 2- to 2.6-fold improvement over a business-as-usual scenario, demonstrating how resilience and ecosystem states are decoupled. Global action to reduce greenhouse gas emissions had little impact on average coral state unless it was accompanied by local controls of fishing. However, combined global and local action reduced the rate of reef degradation threefold. Operationalizing resilience explicitly integrates available biophysical data and accommodates the complex interactions among ecological processes and multiple types of disturbance. [ABSTRACT FROM AUTHOR]

K-selected species with low rates of sexual recruitment may utilise storage effects where low adult mortality allows a number of individuals to persist through time until a favourable recruitment period occurs. Alternative methods of recruitment may become increasingly important for such species if the availability of favourable conditions for sexual recruitment decline under rising anthropogenic disturbance and climate change. Here, we test the hypotheses that asexual dispersal is an integral life history strategy not only in branching corals, as previously reported, but also in a columnar, 'K-selected' coral species, and that its prevalence is driven by the frequency of severe hurricane disturbance. Montastraea annularis is a long-lived major frame-work builder of Caribbean coral reefs but its survival is threatened by the consequences of climate induced disturbance, such as bleaching, ocean acidification and increased prevalence of disease. 700 M. annularis samples from 18 reefs within the Caribbean were genotyped using six polymorphic microsatellite loci. We demonstrate that asexual reproduction occurs at varying frequency across the species-range and significantly contributes to the local abundance of M. annularis, with its contribution increasing in areas with greater hurricane frequency. We tested several competing hypotheses that might explain the observed pattern of genotypic diversity. 64% of the variation in genotypic diversity among the sites was explained by hurricane incidence and reef slope, demonstrating that large-scale disturbances combine with local habitat characteristics to shape the balance between sexual and asexual reproduction in populations of M. annularis. [ABSTRACT FROM AUTHOR]

The Caribbean Sea encompasses a vast range of physical environmental conditions that have a profound influence on the organisms that live there. Here we utilize a range of satellite and in situ products to undertake a region-wide categorization of the physical environments of the Caribbean Sea (PECS). The classification approach is hierarchical and focuses on physical constraints that drive many aspects of coastal ecology, including species distributions, ecosystem function, and disturbance. The first level represents physicochemical properties including metrics of satellite sea surface temperature, water clarity, and in situ salinity. The second level considers mechanical disturbance and includes both chronic disturbance from wind-driven wave exposure and acute disturbance from hurricanes. The maps have a spatial resolution of 1 km². An unsupervised neural network classification produced 16 physicochemical provinces that can be categorized into six broad groups: (1) low water clarity and low salinity and average temperatures; (2) low water clarity but average salinity and temperature, broadly distributed in the basin; (3) low salinity but average water clarity and temperature; (4) upwelling; (5) high latitude; and (6) offshore waters of the inner Caribbean. Additional mechanical disturbance layers impose additional pattern that operates over different spatial scales. Because physical environments underpin so much of coastal ecosystem structure and function, we anticipate that the PECS classification, which will be freely distributed as geographic information system layers, will facilitate comparative analyses and inform the stratification of studies across environmental provinces in the Caribbean basin. [ABSTRACT FROM AUTHOR]

Increasing heat stress due to global climate change is causing coral reef decline, and the Caribbean has been one of the most vulnerable regions. Here, we assessed three decades (1985–2017) of heat stress exposure in the wider Caribbean at ecoregional and local scales using remote sensing. We found a high spatial and temporal variability of heat stress, emphasizing an observed increase in heat exposure over time in most ecoregions, especially from 2003 identified as a temporal change point in heat stress. A spatiotemporal analysis classified the Caribbean into eight heat-stress regions offering a new regionalization scheme based on historical heat exposure patterns. The temporal analysis confirmed the years 1998, 2005, 2010–2011, 2015 and 2017 as severe and widespread Caribbean heat-stress events and recognized a change point in 2002–2004, after which heat exposure has been frequent in most subsequent years. Major heat-stress events may be associated with El Niño Southern Oscillation (ENSO), but we highlight the relevance of the long-term increase in heat exposure in most ecoregions and in all ENSO phases. This work produced a new baseline and regionalization of heat stress in the basin that will enhance conservation and planning efforts underway. [ABSTRACT FROM AUTHOR]

Notionally herbivorous fishes maintains a critical ecosystem function on coral reefs by grazing algae and maintaining highly productive algal turf assemblages. Current paradigms implicate habitat complexity, predation, and primary productivity as major drivers of the distribution and abundance of herbivorous fish, yet little is known about the relative contribution of these factors. Here, we compare bottom‐up and top‐down drivers of notional herbivore assemblages across an environmental gradient of wave exposure in the Palau archipelago. We surveyed herbivore assemblages at reef slopes (6–9 m) across 18 sites, and quantified proxies of top‐down control (predator biomass, habitat complexity) and bottom‐up drivers (net primary production, nutrients) at each site. Despite substantial variability in herbivore biomass throughout the archipelago (6–65 g/m2), general additive models indicate that neither top‐down nor bottom‐up drivers significantly predicted biomass or density of herbivores among sites. In contrast to expectations, herbivore biomass was highest at sites with high predator biomass, low structural complexity, and low benthic productivity. Rather, the highest biomass of herbivores was associated with shallow, tidally emergent, productive reef flats located adjacent to steep vertical walls ("drop‐offs"). The emergent nature of this neighboring habitat precluded occupation by territorial fishes and multiple species of herbivores were observed to make foraging runs into this habitat once tidally inundated. We hypothesize that this habitat configuration provides an important cross‐habitat resource subsidy. Multivariate ordination and permutation of herbivore communities revealed strong evidence for biogeographic partitioning throughout the archipelago (western, southwestern, inner eastern, and outer eastern clusters), contributing to an emerging picture that the habitat heterogeneity of seascapes can overwhelm the effects of conventional top‐down and bottom‐up structuring of herbivory on coral reefs. [ABSTRACT FROM AUTHOR]

Nearshore marine populations are structured in metapopulations that are connected through larval dispersal across national boundaries. One of the main challenges for effective management of these metapopulations is the need for partnerships between nations that share the same resource. By coupling large‐scale connectivity information to a dynamic population model, we analyzed the patterns of connectivity and population persistence for the Caribbean spiny lobster (Panulirus argus) metapopulation both within and across national boundaries. Although spiny lobster subpopulations are highly connected at the basin scale, several nations located in the northern Caribbean and ecoregional networks could persist independently of the larger basin‐wide metapopulation. Based on these results, we propose transnational neighborhoods for spiny lobster management. Our analysis suggests that the dynamics and management of those subpopulations neighborhoods are not intrinsically dependent on "upstream" connectivity even though current rates of upstream larval supply are very high. [ABSTRACT FROM AUTHOR]