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Social–ecological systems (SES) exhibit complex cause‐and‐effect relationships. Capturing, interpreting, and responding to signals that indicate changes in ecosystems is key for sustainable management in SES. Breaks in this signal–response chain, when feedbacks are missing, will allow change to continue until a point when abrupt ecological surprises may occur. In these situations, societies and local ecosystems can often become uncoupled. In this paper, we demonstrate how the red loop–green loop (RL–GL) concept can be used to uncover missing feedbacks and to better understand past social–ecological dynamics. Reinstating these feedbacks in order to recouple the SES may ultimately create more sustainable systems on local scales. The RL–GL concept can uncover missing feedbacks through the characterization of SES dynamics along a spectrum of human resource dependence. Drawing on diverse qualitative and quantitative data sources, we classify SES dynamics throughout the history of Jamaican coral reefs along the RL–GL spectrum. We uncover missing feedbacks in red‐loop and red‐trap scenarios from around the year 600 until now. The Jamaican coral reef SES dynamics have moved between all four dynamic states described in the RL–GL concept: green loop, green trap, red loop and red trap. We then propose mechanisms to guide the current unsustainable red traps back to more sustainable green loops, involving mechanisms of seafood trade and ecological monitoring. By gradually moving away from seafood exports, Jamaica may be able to return to green‐loop dynamics between the local society and their locally sourced seafood. We discuss the potential benefits and drawbacks of this proposed intervention and give indications of why an export ban may insure against future missing feedbacks and could prolong the sustainability of the Jamaican coral reef ecosystem. Our approach demonstrates how the RL–GL approach can uncover missing feedbacks in a coral reef SES, a way the concept has not been used before. We advocate for how the RL–GL concept in a feedback setting can be used to synthesize various types of data and to gain an understanding of past, present and future sustainability that can be applied in diverse social–ecological settings. A free Plain Language Summary can be found within the Supporting Information of this article.

Coral reefs worldwide face an uncertain future with many reefs reported to transition from being dominated by corals to macroalgae. However, given the complexity and diversity of the ecosystem, research on how regimes vary spatially and temporally is needed. Reef regimes are most often characterised by their benthic components; however, complex dynamics are associated with losses and gains in both fish and benthic assemblages. To capture this complexity, we synthesised 3,345 surveys from Hawai‘i to define reef regimes in terms of both fish and benthic assemblages. Model-based clustering revealed five distinct regimes that varied ecologically, and were spatially heterogeneous by island, depth and exposure. We identified a regime characteristic of a degraded state with low coral cover and fish biomass, one that had low coral but high fish biomass, as well as three other regimes that varied significantly in their ecology but were previously considered a single coral dominated regime. Analyses of time series data reflected complex system dynamics, with multiple transitions among regimes that were a function of both local and global stressors. Coupling fish and benthic communities into reef regimes to capture complex dynamics holds promise for monitoring reef change and guiding ecosystem-based management of coral reefs.

We are in the Anthropocene—an epoch where humans are the dominant force of planetary change. Ecosystems increasingly reflect rapid human-induced, socioeconomic and cultural selection rather than being a product of their surrounding natural biophysical setting. This poses the intriguing question: To what extent do existing ecological paradigms capture and explain the current ecological patterns and processes we observe? We argue that, although biophysical drivers still influence ecosystem structure and function at particular scales, their ability to offer predictive capacity over coupled social–ecological systems is increasingly compromised as we move further into the Anthropocene. Traditionally, the dynamics of coral reefs have been studied in response to their proximate drivers of change rather than their underlying socioeconomic and cultural drivers. We hypothesise this is limiting our ability to accurately predict spatial and temporal changes in coral reef ecosystem structure and function. We propose “social–ecological macroecology” as a novel approach within the field of coral reef ecology to a) identify the interactive effects of biophysical and socioeconomic and cultural drivers of coral reef ecosystems across spatial and temporal scales; b) test the robustness of existing coral reef paradigms; c) explore whether existing paradigms can be adapted to capture the dynamics of contemporary coral reefs; and d) if they cannot, develop novel coral reef social–ecological paradigms, where human dynamics are part of the paradigms rather than the drivers of them. Human socioeconomic and cultural processes must become embedded in coral reef ecological theory and practice as much as biophysical processes are today if we are to predict and manage these systems successfully in this era of rapid change. This necessary shift in our approach to coral reef ecology will be challenging and will require truly interdisciplinary collaborations between the natural and social sciences. A plain language summary is available for this article.

In a world of increasing interconnections in global trade as well as rapid change in climate and land cover, the accelerating introduction and spread of invasive species is a critical concern due to associated negative social and ecological impacts, both real and perceived. Much of the societal response to invasive species to date has been associated with negative economic consequences of invasions. This response has shaped a war-like approach to addressing invasions, one with an agenda of eradications and intense ecological restoration efforts towards prior or more desirable ecological regimes. This trajectory often ignores the concept of ecological resilience and associated approaches of resilience-based governance. We argue that the relationship between ecological resilience and invasive species has been understudied to the detriment of attempts to govern invasions, and that most management actions fail, primarily because they do not incorporate adaptive, learning-based approaches. Invasive species can decrease resilience by reducing the biodiversity that underpins ecological functions and processes, making ecosystems more prone to regime shifts. However, invasions do not always result in a shift to an alternative regime; invasions can also increase resilience by introducing novelty, replacing lost ecological functions or adding redundancy that strengthens already existing structures and processes in an ecosystem. This paper examines the potential impacts of species invasions on the resilience of ecosystems and suggests that resilience-based approaches can inform policy by linking the governance of biological invasions to the negotiation of tradeoffs between ecosystem services.

Resilience underpins the sustainability of both ecological and social systems. Extensive loss of reef corals following recent mass bleaching events have challenged the notion that support of system resilience is a viable reef management strategy. While resilience-based management (RBM) cannot prevent the damaging effects of major disturbances, such as mass bleaching events, it can support natural processes that promote resistance and recovery. Here, we review the potential of RBM to help sustain coral reefs in the 21st century. We explore the scope for supporting resilience through existing management approaches and emerging technologies and discuss their opportunities and limitations in a changing climate. We argue that for RBM to be effective in a changing world, reef management strategies need to involve both existing and new interventions that together reduce stress, support the fitness of populations and species, and help people and economies to adapt to a highly altered ecosystem.

Much of the Earth’s biosphere has been appropriated for the production of harvestable biomass in the form of food, fuel and fibre. Here we show that the simplification and intensification of these systems and their growing connection to international markets has yielded a global production ecosystem that is homogenous, highly connected and characterized by weakened internal feedbacks. We argue that these features converge to yield high and predictable supplies of biomass in the short term, but create conditions for novel and pervasive risks to emerge and interact in the longer term. Steering the global production ecosystem towards a sustainable trajectory will require the redirection of finance, increased transparency and traceability in supply chains, and the participation of a multitude of players, including integrated ‘keystone actors’ such as multinational corporations. This Perspective examines the global production ecosystem through the lenses of connectivity, diversity and feedback, and proposes measures that will increase its stability and sustainability.

A major challenge for coral reef conservation and management is understanding how a wide range of interacting human and natural drivers cumulatively impact and shape these ecosystems. Despite the importance of understanding these interactions, a methodological framework to synthesize spatially explicit data of such drivers is lacking. To fill this gap, we established a transferable data synthesis methodology to integrate spatial data on environmental and anthropogenic drivers of coral reefs, and applied this methodology to a case study location–the Main Hawaiian Islands (MHI). Environmental drivers were derived from time series (2002–2013) of climatological ranges and anomalies of remotely sensed sea surface temperature, chlorophyll-a, irradiance, and wave power. Anthropogenic drivers were characterized using empirically derived and modeled datasets of spatial fisheries catch, sedimentation, nutrient input, new development, habitat modification, and invasive species. Within our case study system, resulting driver maps showed high spatial heterogeneity across the MHI, with anthropogenic drivers generally greatest and most widespread on O‘ahu, where 70% of the state’s population resides, while sedimentation and nutrients were dominant in less populated islands. Together, the spatial integration of environmental and anthropogenic driver data described here provides a first-ever synthetic approach to visualize how the drivers of coral reef state vary in space and demonstrates a methodological framework for implementation of this approach in other regions of the world. By quantifying and synthesizing spatial drivers of change on coral reefs, we provide an avenue for further research to understand how drivers determine reef diversity and resilience, which can ultimately inform policies to protect coral reefs.

Cumulative pressures from global climate and ocean change combined with multiple regional and local-scale stressors pose fundamental challenges to coral reef managers worldwide. Understanding how cumulative stressors affect coral reef vulnerability is critical for successful reef conservation now and in the future. In this review, we present the case that strategically managing for increased ecological resilience (capacity for stress resistance and recovery) can reduce coral reef vulnerability (risk of net decline) up to a point. Specifically, we propose an operational framework for identifying effective management levers to enhance resilience and support management decisions that reduce reef vulnerability. Building on a system understanding of biological and ecological processes that drive resilience of coral reefs in different environmental and socio-economic settings, we present an Adaptive Resilience-Based management (ARBM) framework and suggest a set of guidelines for how and where resilience can be enhanced via management interventions. We argue that press-type stressors (pollution, sedimentation, overfishing, ocean warming and acidification) are key threats to coral reef resilience by affecting processes underpinning resistance and recovery, while pulse-type (acute) stressors (e.g. storms, bleaching events, crown-of-thorns starfish outbreaks) increase the demand for resilience. We apply the framework to a set of example problems for Caribbean and Indo-Pacific reefs. A combined strategy of active risk reduction and resilience support is needed, informed by key management objectives, knowledge of reef ecosystem processes and consideration of environmental and social drivers. As climate change and ocean acidification erode the resilience and increase the vulnerability of coral reefs globally, successful adaptive management of coral reefs will become increasingly difficult. Given limited resources, on-the-ground solutions are likely to focus increasingly on actions that support resilience at finer spatial scales, and that are tightly linked to ecosystem goods and services.

Coral reefs worldwide face unprecedented cumulative anthropogenic effects of interacting local human pressures, global climate change and distal social processes. Reefs are also bound by the natural biophysical environment within which they exist. In this context, a key challenge for effective management is understanding how anthropogenic and biophysical conditions interact to drive distinct coral reef configurations. Here, we use machine learning to conduct explanatory predictions on reef ecosystems defined by both fish and benthic communities. Drawing on the most spatially extensive dataset available across the Hawaiian archipelago—20 anthropogenic and biophysical predictors over 620 survey sites—we model the occurrence of four distinct reef regimes and provide a novel approach to quantify the relative influence of human and environmental variables in shaping reef ecosystems. Our findings highlight the nuances of what underpins different coral reef regimes, the overwhelming importance of biophysical predictors and how a reef's natural setting may either expand or narrow the opportunity space for management interventions. The methods developed through this study can help inform reef practitioners and hold promises for replication across a broad range of ecosystems.

Both coral-dominated and degraded reef ecosystems can be resistant to change. Typically, research and management have focused on maintaining coral dominance and avoiding phase shifts to other species compositions, rather than on weakening the resilience of already degraded reefs to re-establish coral dominance. Reversing degraded coral-reef states will involve reducing local chronic drivers like fishing pressure and poor water quality. Reversals will also require management of key ecological processes - such as those performed by different functional groups of marine herbivores - that both weaken the resilience of the degraded state and strengthen the coral-dominated state. If detrimental human impacts are reduced and key ecological processes are enhanced, pulse disturbances, such as extreme weather events, and ecological variability may provide opportunities for a return to a coral-dominated state. Critically, achieving these outcomes will necessitate a diverse range of integrated approaches to alter human interactions with reef ecosystems.

Coral reef fish are an important source of food security and income for human coastal populations. They also underpin ecosystem processes vital for the future ability of coral reefs to generate eco ...

Ecosystems are shaped by natural processes such as predator–prey interactions and climate, as well as by human activities such as harvesting and pollution. Resilient ecosystems are able to absorb disturbances, but chronic stressors may reduce the capacity of an ecosystem to cope with change (Trends Ecol Evol 15:413–417, 2000). The ability of ecosystems to absorb disturbance and at the same time maintain their structure, processes, and function is known as resilience (sensu Ann Rev Ecol Evol Syst 4:1–23, 1973). Accumulated evidence from many systems (e.g., coral reefs, forests, rangelands, and shallow lakes) suggests that when pushed past a threshold (i.e., beyond their resilience), ecosystems can undergo a regime shift to an alternative state (Resilience thinking: sustaining ecosystems and people in a changing world, Washington, DC, 2006; Am Zool 32:674–682, 1992; J Anim Ecol 59:1147–1164, 1990; Trends Ecol Evol 8:275–279, 1993; Ecol Soc 6:17–28, 2011). From an anthropocentric perspective these alternative states may be less desirable than the initial state depending on the ecosystem goods and services they produce (Ecol Econ 29:215–233, 1999). Strong feedbacks in the alternate state may also make recovery to the original state difficult, even after the original stressors are removed (Nature 413:591–596, 2001; Ecosystems 15:695–710, 2012). Human dimensions such as opportunity and governance also comprise an important aspect of resilience because they influence how sustainably resources are used (Science 325:419–422, 2009; Curr Biol 19:206–212, 2009), thereby shifting the resilience threshold. The objectives of this lab are to.

Anthropogenic changes to the Earth now rival those caused by the forces of nature and have shepherded us into a new planetary epoch – the Anthropocene. Such changes include profound and often unexpected alterations to coral reef ecosystems and the services they provide to human societies. Ensuring that reefs and their services endure during the Anthropocene will require that key drivers of coral reef change – fishing, water quality, and anthropogenic climate change – stay within acceptable levels or “safe operating spaces”. The capacity to remain within these safe boundaries hinges on understanding the local, but also the increasingly global and cross-scale, socioeconomic causes of these human drivers of change. Consequently, local and regional management efforts that are successful in the short term may ultimately fail if current decision making and institution-building around coral reef systems remains fragmented, poorly coordinated, and unable to keep pace with the escalating speed of social, technological, and ecological change.

In many coastal areas, marine ecosystems have shifted into contrasting states having reduced ecosystem services (hereafter called degraded). Such degraded ecosystems may be slow to revert to their original state due to new ecological feedbacks that reinforce the degraded state. A better understanding of the way human actions influence the strength and direction of feedbacks, how different feedbacks could interact, and at what scales they operate, may be necessary in some cases for successful management of marine ecosystems. Here we synthesize interactions of critical feedbacks of the degraded states from six globally distinct biomes: coral reefs, kelp forests, seagrass beds, shallow soft sediments, oyster reefs, and coastal pelagic food webs. We explore to what extent current management captures these feedbacks and propose strategies for how and when (that is, windows of opportunity) to influence feedbacks in ways to break the resilience of the degraded ecosystem states. We conclude by proposing some challenges for future research that could improve our understanding of these issues and emphasize that management of degraded marine states will require a broad social–ecological approach to succeed.

Despite recent advances, ecosystem service monitoring is limited by insufficient data, the complexity of social–ecological systems, and poor integration of information that tracks changes in ecosystems and economic activities. However, new information and communication technologies are revolutionizing the generation of, and access to, such data. Can researchers who are interested in ecological monitoring tap into these increased flows of information by “mining” the internet to detect “early-warning” signs that may signal abrupt ecological changes? Here, we explore the possibility of using web crawlers and internet-based information to complement conventional ecological monitoring, with a special emphasis on the prospects for avoiding “late warnings”– that is, when ecosystems have already shifted to less desirable states. Using examples from coral reef ecosystems, we explore the untapped potential, as well as the limitations, of relying on web-based information to monitor ecosystem services and forewarn us of negative ecological shifts.

To improve coral reef management, a deeper understanding of biodiversity across scales in the context of functional groups is required. The focus of this paper is on the role of diversity within functional groups in securing important ecosystem processes that contribute to the resilience of coral-dominated reef states. Two important components of species biodiversity that confer ecosystem resilience are analyzed: redundancy and the diversity of responses within functional groups to change. Three critical functional groups are used to illustrate the interaction between these two components and their role in coral reef resilience: zooxanthellae (symbiotic micro algae in reef-building corals), reef-building corals, and herbivores. The paper further examines the consequences of undermining functional redundancy and response diversity and addresses strategies to secure ecological processes that are critical for coral reef resilience.

The worldwide decline of coral reefs calls for an urgent reassessment of current management practices. Confronting large-scale crises requires a major scaling-up of management efforts based on an improved understanding of the ecological processes that underlie reef resilience. Managing for improved resilience, incorporating the role of human activity in shaping ecosystems, provides a basis for coping with uncertainty, future changes and ecological surprises. Here we review the ecological roles of critical functional groups (for both corals and reef fishes) that are fundamental to understanding resilience and avoiding phase shifts from coral dominance to less desirable, degraded ecosystems. We identify striking biogeographic differences in the species richness and composition of functional groups, which highlight the vulnerability of Caribbean reef ecosystems. These findings have profound implications for restoration of degraded reefs, management of fisheries, and the focus on marine protected areas and biodiversity hotspots as priorities for conservation.

Ecological structures and processes occur at specific spatiotemporal scales, and interactions that occur across multiple scales mediate scale-specific (e.g., individual, community, local, or regional) responses to disturbance. Despite the importance of scale, explicitly incorporating a multi-scale perspective into research and management actions remains a challenge. The discontinuity hypothesis provides a fertile avenue for addressing this problem by linking measureable proxies to inherent scales of structure within ecosystems. Here we outline the conceptual framework underlying discontinuities and review the evidence supporting the discontinuity hypothesis in ecological systems. Next we explore the utility of this approach for understanding cross-scale patterns and the organization of ecosystems by describing recent advances for examining nonlinear responses to disturbance and phenomena such as extinctions, invasions, and resilience. To stimulate new research, we present methods for performing discontinuity analysis, detail outstanding knowledge gaps, and discuss potential approaches for addressing these gaps.

There have been several earlier studies that addressed the influence of natural disturbance regimes on coral reefs. Humans alter natural disturbance regimes, introduce new stressors, and modify background conditions of reefs. We focus on how coral reef ecosystems relate to disturbance in an increasingly human-dominated environment. The concept of ecosystem resilience—that is, the capacity of complex systems with multiple stable states to absorb disturbance, reorganize, and adapt to change—is central in this context. Instead of focusing on the recovery of certain species and populations within disturbed sites of individual reefs, we address spatial resilience—that is, the dynamic capacity of a reef matrix to reorganize and maintain ecosystem function following disturbance. The interplay between disturbance and ecosystem resilience is highlighted. We begin the identification of spatial sources of resilience in dynamic seascapes and exemplify and discuss the relation between “ecological memory” (biological legacies, mobile link species, and support areas) and functional diversity for seascape resilience. Managing for resilience in dynamic seascapes not only enhances the likelihood of conserving coral reefs, it also provides insurance to society by sustaining essential ecosystem services.

Production ecosystems typically have a high dependence on supporting and regulating ecosystem services and while they have thus far managed to sustain production, this has often been at the cost of externalities imposed on other systems and locations. One of the largest challenges facing humanity is to secure the production of food and fiber while avoiding long-term negative impacts on ecosystems and the range of services that they provide. Resilience has been used as a framework for understanding sustainability challenges in a range of ecosystem types, but has not been systematically applied across the range of systems specifically used for the production of food and fiber in terrestrial, freshwater, and marine environments. This paper applied a resilience lens to production ecosystems in which anthropogenic inputs play varying roles in determining system dynamics and outputs. We argue that the traditional resilience framework requires important additions when applied to production systems. We show how sustained anthropogenic inputs of external resources can lead to a "coercion'' of resilience and describe how the global interconnectedness of many production systems can camouflage signals indicating resilience loss.

The relationship between species richness and area is one of the oldest, most recognized patterns in ecology. Here we provide empirical evidence for strong impacts of fisheries exploitation on the slope of the species-area relationship (SAR). Using comparative field surveys of fish on protected and exploited reefs in three oceans and the Mediterranean Sea, we show that exploitation consistently depresses the slope of the SAR for both power-law and exponential models. The magnitude of change appears to be proportional to fishing intensity. Results are independent of taxonomic resolution and robust across coral and rocky reefs, sampling protocols and statistical methods. Changes in species richness, relative abundance and patch occupancy all appear to contribute to this pattern. We conclude that exploitation pressure impacts the fundamental scaling of biodiversity as well as the species richness and spatial distribution patterns of reef fish. We propose that species-area curves can be sensitive indicators of community-level changes in biodiversity, and may be useful in quantifying the human imprint on reef biodiversity, and potentially elsewhere.

Conventional perceptions of the interactions between people and their environment are rapidly transforming. Old paradigms that view humans as separate from nature, natural resources as inexhaustible or endlessly substitutable, and the world as stable, predictable, and in balance are no longer tenable. New conceptual frameworks are rapidly emerging based on an adaptive approach that focuses on learning and flexible management in a dynamic social-ecological landscape. Using two iconic World Heritage Areas as case studies (the Great Barrier Reef and the Grand Canyon) we outline how an improved integration of the scientific and social aspects of natural resource management can guide the evolution of multiscale systems of governance that confront and cope with uncertainty, risk, and change in an increasingly human-dominated world.

In a world increasingly modified by human activities, the conservation of biodiversity is essential as insurance to maintain resilient ecosystems and ensure a sustainable flow of ecosystem goods and services to society. However, existing reserves and national parks are unlikely to incorporate the long-term and large-scale dynamics of ecosystems. Hence, conservation strategies have to actively incorporate the large areas of land that are managed for human use. For ecosystems to reorganize after large-scale natural and human-induced disturbances, spatial resilience in the form of ecological memory is a prerequisite. The ecological memory is composed of the species, interactions and structures that make ecosystem reorganization possible, and its components may be found within disturbed patches as well in the surrounding land-scape. Present static reserves should be complemented with dynamic reserves, such as ecological fallows and dynamic successional reserves, that are part of ecosystem management mimicking natural disturbance regimes at the landscape level.

The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.

Loss of coral reef resilience can lead to dramatic changes in benthic structure, often called regime shifts, which significantly alter ecosystem processes and functioning. In the face of global change and increasing direct human impacts, there is an urgent need to anticipate and prevent undesirable regime shifts and, conversely, to reverse shifts in already degraded reef systems. Such challenges require a better understanding of the human and natural drivers that support or undermine different reef regimes. The Hawaiian archipelago extends across a wide gradient of natural and anthropogenic conditions and provides us a unique opportunity to investigate the relationships between multiple reef regimes, their dynamics and potential drivers. We applied a combination of exploratory ordination methods and inferential statistics to one of the most comprehensive coral reef datasets available in order to detect, visualize and define potential multiple ecosystem regimes. This study demonstrates the existence of three distinct reef regimes dominated by hard corals, turf algae or macroalgae. Results from boosted regression trees show nonlinear patterns among predictors that help to explain the occurrence of these regimes, and highlight herbivore biomass as the key driver in addition to effluent, latitude and depth.

Facing a human-dominated world, ecologists are now reconsidering the role of disturbance for coral reef ecosystem dynamics. Human activities alter the natural disturbance regimes of coral reefs by transforming pulse events into persistent disturbance or even chronic stress, by introducing new disturbance, or by suppressing or removing disturbance. Adding these alterations to natural disturbance regimes will probably result in unknown synergistic effects. Simultaneously, humans are altering the capacity of reefs to cope with disturbance (e.g. by habitat fragmentation and reduction of functional diversity), which further exacerbates the effects of altered disturbance regimes. A disturbance that previously triggered the renewal and development of reefs might, under such circumstances, become an obstacle to development. The implications of these changes for reef-associated human activities, such as fishing and tourism, can be substantial.

We welcome the comments made by Scully and Ostrander, which highlight that phase shifts can occur in coral areas that are not under immediate anthropogenic influence, and that they might be a natural ingredient in the dynamics of modern coral reefs. To understand such changes, we do indeed need to address the influence of natural disturbance regimes on coral reef communities, and learn more about the complex interactions between corals and macroalgae. Unfortunately, there might only be few, if any, pristine coral reefs left on which to study phase-shifts and natural disturbance regimes [Refs 1xReefs since Columbus. Jackson, J.B.C. Coral Reefs. 1997; 16: 23–32CrossrefSee all References1,2xVarieties of science for coral reef management. Hatcher, B.G. Coral Reefs. 1999; 18: 305–306Crossref | Scopus (7)See all References2 and see Bryant, D. et al. (1998) Reefs at risk. A map-based indicator of potential threats to the world's coral reefs: http://www.wri.org/wri/indictrs/reefrisk.htm]. A major point in our review3xCoral reef disturbance and resilience in a human-dominated environment. Nystrom, M et al. Trends Ecol. Evol. 2000; 15: 413–417Abstract | Full Text | Full Text PDF | PubMed | Scopus (353)See all References3 was that these shifts seem to have become more frequent and less reversible because of human impacts and that humans might also alter the magnitude, frequency and duration of disturbance regimes.Many of the world's coral reefs assumed to be pristine show signs of overfishing of highly valued predatory fishes4xCoral reef fishing and coral-algal phase shifts: implications for global reef status. McManus, J.W et al. ICES J. Mar. Sci. 2000; 57: 572–578Crossref | Scopus (54)See all References4 and might already have been overfished when intensive scientific investigations began1xReefs since Columbus. Jackson, J.B.C. Coral Reefs. 1997; 16: 23–32CrossrefSee all References1. In addition, reefs with no discernible human influences might suffer from indirect human influence at scales that reach far beyond the border of the individual reef, such as global warming, increased levels of carbon dioxide5xExecutive summary. Wilkinson, C.R. : 7–19See all References5 and dust6xAfrican dust and the demise of Caribbean coral reefs. Shinn, E.A et al. Geophys. Res. Lett. 2000; 27: 3029–3032CrossrefSee all References6. Subtle interactions of a number of factors7xRapid transition in the structure of a coral reef community: The effects of coral bleaching and physical disturbance. Ostrander, G.K et al. Proc. Natl. Acad. Sci. U. S. A. 2000; 97: 5297–5302Crossref | PubMed | Scopus (87)See all References7 can lead to a loss of ecosystem resilience that is difficult to detect until a reef shifts to another stability domain caused by a disturbance that could previously be absorbed8xMacroalgae, nutrients and phase shifts on coral reefs: scientific issues and management consequences for the Great Barrier Reef. McCook, L.J. Coral Reefs. 1999; 18: 357–367Crossref | Scopus (335)See all References8. Thus, what we experience as a fast transition (within months) from one state to another might be the result of a long-term gradual change over years, decades or even centuries.This raises some key questions for future research. How do we detect gradual loss of resilience and how can we qualitatively and quantitatively measure such loss, and incorporate this knowledge in the management of coral reefs? Our understanding of factors that might signal loss of resilience is, however, still in its infancy.In order to secure the ability of coral reefs to provide humans with ecological goods and services9xEcological goods and services of coral reef ecosystems. Moberg, F and Folke, C. Ecol. Econ. 1999; 29: 215–233Crossref | Scopus (430)See all References9, we must understand the properties that enable coral reef ecosystems to maintain their resilience in the face of an increasingly human-dominated world with altered disturbance regimes3xCoral reef disturbance and resilience in a human-dominated environment. Nystrom, M et al. Trends Ecol. Evol. 2000; 15: 413–417Abstract | Full Text | Full Text PDF | PubMed | Scopus (353)See all References3.