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Who Should Pick the Winners of Climate Change?
Abstract
Many conservation strategies identify a narrow subset of genotypes, species, or geographic locations that are predicted to be favored under different scenarios of future climate change. However, a focus on predicted winners, which might not prove to be correct, risks undervaluing the balance of biological diversity from which climate-change winners could otherwise emerge. Drawing on ecology, evolutionary biology, and portfolio theory, we propose a conservation approach designed to promote adaptation that is less dependent on uncertain predictions about the identity of winners and losers. By designing actions to facilitate numerous opportunities for selection across biological and environmental conditions, we can allow nature to pick the winners and increase the probability that ecosystems continue to provide services to humans and other species.
... Our goal in this paper is to summarize what we refer to as assisting adaptation, which is the range of potential management interventions available to help organisms, populations, and ecosystems adjust to ongoing, and especially climate-driven, environmental change while highlighting some of their potential benefits and risks. Organisms, populations, and ecosystems respond to environmental change through a suite of biological processes that occur across a range of scales of organization-including acclimatization, evolution, range shifts, and ecological reorganization-that we collectively refer to as adaptation because they are all processes by which biological systems adjust to environmental change (Webster et al., 2017). Note that this definition is broader than the evolutionary definition of adaptation that refers only to genetic changes, but is consistent with the growing use of the term in conservation biology to refer to how human and nonhuman organisms adjust to environmental change (e.g., Morecroft et al., 2019;Tittensor et al., 2019;Wilson et al., 2020;Jacquemont et al., 2022). ...
... Conservation biologists are exploring two primary approaches to assisting evolution. First, species can be managed to maintain or increase local population size and metapopulation connectivity to indirectly influence the amount of genetic variance available for natural selection (Sgrò et al., 2011;Webster et al., 2017;Walsworth et al., 2019;Colton et al., 2022). The assumption in this case is that enough genetic variation exists within a metapopulation to support evolutionary adaptation, provided that management actions increase local abundance and/or facilitate natural geneflow. ...
... Managing for ecosystem adaptation can use some of the same tools used for facilitating population and species adaptation. For example, managing large, connected, and abiotically representative networks of protected areas can preserve the processes that promote the adaptation (i.e., acclimatization, range shifts, and evolution) of multiple species in ways that may result in shifts in community composition and species' functional roles (e.g., Beier and Brost, 2010;Webster et al., 2017). It is also possible to direct the reorganization of an ecosystem by actively manipulating the abundance and composition of select species over time to achieve a particular goal, as exemplified theoretically in renewal ecology (Bowman et al., 2017) and the creation of designer ecosystems (Aswani et al., 2018), and in specific case examples like forestry (Ontl et al., 2020). ...
Today, all ecosystems are undergoing environmental change due to human activity, and in many cases the rate of change is accelerating due to climate change. Consequently, conservation programs are increasingly focused on the response of organisms, populations, and ecosystems to novel conditions. In parallel, the field of conservation biology is developing and deploying new tools to assist adaptation, which we define as aiming to increase the probability that organisms, populations, and ecosystems successfully adapt to ongoing change in biotic and abiotic conditions. Practitioners are aiming to assist a suite of adaptive processes, including acclimatization, range shifts, and evolution, at the individual and population level, while influencing the aggregate of these responses to assist ecosystem reorganization. The practice of assisting adaptation holds promise for environmental conservation, but effective policy and implementation will require thoughtful consideration of potential social and biological benefits and risks.
... Genetic variability, including single nucleotide base pair substitution, insertion-deletion and structural variability, can result in the presence of species with redundant functions (Li et al. 2015) as well as genotypes within species that encode variable responses to environmental pressures. These support ecosystem stability and ensure that ecosystems remain functional even if unpredictable changes lead to the loss of some species, or the loss of within-species genetic diversity at the population level (Webster et al. 2017). For example, genetic variability across more than 100 discrete populations of Bristol Bay salmon in Alaska entails greater heterogeneity and resilience to anomalous conditions, resulting in lower variability in fisheries production and greater stability than that of a homogeneous population. ...
... Corals also provide context for this adaptive capacity with their ability to respond relatively quickly via symbiont and microbiome shuffling, phenotypic plasticity, acclimatisation and adaptation. Some corals may have already adapted to ocean warming since the Industrial Revolution (Webster et al. 2017). ...
... When fully and highly protected, MPA networks provide a unique opportunity to protect storehouses of genetic diversity in a changing ocean. As organisms adapt to these changing conditions (see Sect. 2.1), adaptation networks can be established to identify and protect areas where genetic diversity and/or the potential for adaptation is high (Webster et al. 2017). For example, in coral reef systems, adaptation networks may be particularly useful as corals are increasingly threatened by rising temperatures, ocean acidification, pollution and overfishing (Hughes et al. 2018) while simultaneously showing quantifiably high rates of adaptation (Munday et al. 2013). ...
The ‘ocean genome’ is the foundation upon which all marine ecosystems rest and is defined here as the ensemble of genetic material present in all marine biodiversity, including both the physical genes and the information they encode. The dynamics of the ocean genome enable organisms to adapt to diverse ecological niches and changing environmental conditions. The ocean genome also determines the productivity and resilience of biological resources, including fisheries and aquaculture, which collectively support global food security, human well-being and a sustainable ocean economy.
... More generally, the resilience of ecological systems, such as a metapopulation, relies on the connectivity and the diversity of responses of its components (Elmqvist et al. 2003;Webster et al. 2017). Indeed, there is growing recognition that a diverse network of populations can promote overall stability of population complexes and resource flows (e.g., fishery yields, Schindler et al. 2010). ...
... Our study focused on the consequences of dispersal scenarios to shed light on the influence of connectivity alone on eco-evolutionary processes. However, adaptation network theory (Webster et al. 2017; Fig. 7) states that the resilience of ecological systems, such as metapopulation, relies on the connectivity as well as response diversity of its components (Elmqvist et al. 2003). Recent theoretical studies of coral reefs have emphasized that population diversity is beneficial for metapopulation persistence and stability in the context of a changing and uncertain climate (Walsworth et al. 2019;McManus et al. 2021a). ...
... Additionally, we discuss ideas for future directions using the model to explore responses of interconnected Atlantic salmon populations to environmental change and spatially structured management. Finally, we advocate for a management of populations within the adapta-tion network framework (Webster et al. 2017; Fig. 7) because maintaining diversity and evolutionary options within a network of populations is a critical step for fostering species persistence and stability in the face of environmental change (Walsworth et al. 2019). ...
Despite growing evidence of spatial dispersal and gene flow between salmonid populations, the implications of connectivity for adaptation, conservation, and management are still poorly appreciated. Here, we explore the influence of a gradient of dispersal rates on portfolio strength and eco-evolutionary dynamics in a simulated population network of Atlantic salmon (Salmo salar) by extending a demo-genetic agent-based model to a spatially explicit framework. Our model results highlight a non-linear relationship between dispersal rates and the stability of the metapopulation, resulting in an optimal portfolio effect for dispersal rates around 20%. At local population scale, we also demonstrate phenotypic changes induced by density-dependent effects modulated by dispersal, and a dispersal-induced increase in genetic diversity. We conclude that it is critical to account for complex interactions between dispersal and eco-evolutionary processes and discuss future avenues of research that could be addressed by such modeling approaches to more fully appreciate responses of Atlantic salmon to environmental changes and investigate management actions accordingly.
... In addition, considering branches ensures cost-effective protection because Box 2. SCP as a framework to place new conservation areas SCP can be treated as a mathematical problem involving the spatial distribution of biodiversity features (e.g., species, indexed by j=1, …, S) and conservation costs in a set of sites indexed by i=1, …, N. r ij indicates the spatial occurrence (binary variable) or abundance (continuous variable) of biodiversity feature j in site i. In one of the several possible types of SCP problem, the minimum set coverage [71], the mathematical formulation involves Equations I and II: ...
... when future environmental conditions are uncertain [71] and buffers the risk of incorrectly characterized gene-environment associations. Depending on the genetic structure of the species, intraspecific genetic diversity can be conserved either by prioritizing sites with the highest within-site diversity (alpha diversity) or by protecting sets of sites with complementary genetic variants to maximize adaptation capacity at the landscape scale (beta diversity; Box 3). ...
... How would one select the species to collect genetic data on? Box 3. Retaining adaptive genetic diversity to foster persistence under uncertain future conditions Prioritizing portfolios of genetic combinations increases the probability that 'winning' combinations can persist during periods of environmental change [71]. Depending on the genetic structure of the species, targeting sites with high within-site adaptive genetic diversity or sites with populations adapted to different local conditions will help build conservation area networks that retain the genetic diversity of species. ...
Spatial conservation prioritization (SCP) is a planning framework used to identify new conservation areas on the basis of the spatial distribution of species, ecosystems, and their services to human societies. The ongoing accumulation of intraspecific genetic data on a variety of species offers a way to gain knowledge of intraspecific genetic diversity and to estimate several population characteristics useful in conservation, such as dispersal and population size. Here, we review how intraspecific genetic data have been integrated into SCP and highlight their potential for identifying conservation area networks that represent intraspecific genetic diversity comprehensively and that ensure the long-term persistence of biodiversity in the face of global change.
... Inclusion of a diverse portfolio of reef types in marine management and planning is considered a means to reduce risk [11,93] and maximise adaptive potential under the uncertainty of climate change [94]. The diverse characteristics of reef safe haven locations supports a broad set of protective services that have seen them identified as having disproportionately high conservation value worthy of targeted protection [15,36,58] and inclusion within protected networks [95,96]. ...
... Safe havens that promote innate coral tolerance (e.g. hotspots of resilience) are habitats identified as well suited for inclusion in adaptive networks; a regional system of managed areas with attributes that promote adaption [93]. Adaptive networks are constructed to allow nature to determine the winners of climate change [93]. ...
... hotspots of resilience) are habitats identified as well suited for inclusion in adaptive networks; a regional system of managed areas with attributes that promote adaption [93]. Adaptive networks are constructed to allow nature to determine the winners of climate change [93]. Identifying and learning from coral reef bright spots that account for social and environmental interactions can facilitate innovative conservation efforts in the face of climate change [16], while contemporary near-pristine reefs are considered important to help establish management targets [47]. ...
Reducing the global reliance on fossil fuels is essential to ensure the long-term survival of coral reefs, but until this happens, alternative tools are required to safeguard their future. One emerging tool is to locate areas where corals are surviving well despite the changing climate. Such locations include refuges, refugia, hotspots of resilience, bright spots, contemporary near-pristine reefs, and hope spots that are collectively named reef ‘safe havens' in this mini-review. Safe havens have intrinsic value for reefs through services such as environmental buffering, maintaining near-pristine reef conditions, or housing corals naturally adapted to future environmental conditions. Spatial and temporal variance in physicochemical conditions and exposure to stress however preclude certainty over the ubiquitous long-term capacity of reef safe havens to maintain protective service provision. To effectively integrate reef safe havens into proactive reef management and contingency planning for climate change scenarios, thus requires an understanding of their differences, potential values, and predispositions to stress. To this purpose, I provide a high-level review on the defining characteristics of different coral reef safe havens, how they are being utilised in proactive reef management and what risk and susceptibilities they inherently have. The mini-review concludes with an outline of the potential for reef safe haven habitats to support contingency planning of coral reefs under an uncertain future from intensifying climate change.
... In a world increasingly affected by anthropogenic disturbances and large changes in species abundance (Parmesan 2006, Walther 2010, searches for species that are resistant to future conditions are intensifying (Webster et al. 2017). The objectives of these efforts include obtaining a better understanding of ecosystems of the future, directing restoration efforts to effect beneficial outcomes, and enhancing food security under novel environmental conditions (Webster et al. 2017, Tyczewska et al. 2018. ...
... In a world increasingly affected by anthropogenic disturbances and large changes in species abundance (Parmesan 2006, Walther 2010, searches for species that are resistant to future conditions are intensifying (Webster et al. 2017). The objectives of these efforts include obtaining a better understanding of ecosystems of the future, directing restoration efforts to effect beneficial outcomes, and enhancing food security under novel environmental conditions (Webster et al. 2017, Tyczewska et al. 2018. Organisms effectively are being sought that have high fitness under specified conditions (Hoffmann and Sgro 2011), but the task often is described as a search for winners (Loya et al. 2001, Somero 2010. ...
... Together, these disturbances are causing changes in coral reefs that sum to the coral reef crisis (Hughes et al. 2010, Bellwood et al. 2019, and they have motivated research to identify corals with the capacity to thrive in future seas (van Oppen et al. 2015) and to find reef oases that might facilitate reef regeneration (Guest et al. 2018). Emerging from these efforts has been consideration of the ability of humans vs. nature to accurately select winners among the present-day coral fauna (Webster et al. 2017). ...
The biological world is rapidly changing following decades of anthropogenic disturbances. Under these conditions, species with stable or increasing abundances have been described as winners with the potential for future success, but this assertion is unreliable without knowledge of the selective basis of winning. The incentive to find winners is acute for reef corals, for which large declines in abundance have motivated restoration efforts targeting winning corals. On Caribbean reefs, Porites astreoides has emerged as a potential winner, but the demographic basis of this categorization is poorly known. Here we test for demographic benchmarks of winning in this species by quantifying abundances and sizes of colonies over 28 yr on the south coast of St. John, US Virgin Islands. From 1992 to 2001, the density of colonies of P. astreoides showed little variation while colonies increased in size by 58%, but from 2002 to 2019, population density increased 2.7‐fold, and colony size declined by 41%; accompanying these trends, the mean absolute cover of Porites spp. declined by 46% from 2010 to 2019. Low recruitment and rising abundances of colonies ≤4 cm diameter suggest that partial mortality and fission depressed colony sizes. The reversal over three decades of a positive demographic trend for a ubiquitous coral underscores the challenges of identifying winners from short‐term population performance. Without a mechanistic understanding of fitness, the search for winners based on demographic trends may be futile.
... Rapid human-induced climate change has led to an urgent need to identify the genetic, species, and trait diversity associated with the ability of ecosystems to avoid regime shifts (Webster et al. 2017). An important element of diversity that maintains ecosystem states is response diversity (sensu Elmqvist et al. 2003), where species sharing similar ecological functions differ in their response to perturbations (Chapin et al. 1997, Yachi andLoreau 1999). ...
... 6 cover at coarse taxonomic levels. The results presented here have important implications for identifying ecological portfolios (Webster et al. 2017) at Moorea and surrounding islands, where diversity in environmental conditions, habitat types, phenotypes, and genotypes would buffer the capacity for Pocillopora to absorb impacts of climate change (van Woesik 2017, Webster et al. 2017). Since at least the 1970s, coral cover at Moorea has seen large declines and recovery on multiple occasions, where coral cover has become increasingly dominated by corals in the genus Pocillopora after each recovery period (Berumen and Pratchett 2006, Adjeroud et al. 2018, Holbrook et al. 2018, McWilliam et al. 2020. ...
... 6 cover at coarse taxonomic levels. The results presented here have important implications for identifying ecological portfolios (Webster et al. 2017) at Moorea and surrounding islands, where diversity in environmental conditions, habitat types, phenotypes, and genotypes would buffer the capacity for Pocillopora to absorb impacts of climate change (van Woesik 2017, Webster et al. 2017). Since at least the 1970s, coral cover at Moorea has seen large declines and recovery on multiple occasions, where coral cover has become increasingly dominated by corals in the genus Pocillopora after each recovery period (Berumen and Pratchett 2006, Adjeroud et al. 2018, Holbrook et al. 2018, McWilliam et al. 2020. ...
Variation among functionally similar species in their response to environmental stress buffers ecosystems from changing states. Functionally similar species may often be cryptic species representing evolutionarily distinct genetic lineages that are morphologically indistinguishable. However, the extent to which cryptic species differ in their response to stress, and could therefore provide a source of response diversity, remains unclear because they are often not identified or are assumed to be ecologically equivalent. Here, we uncover differences in the bleaching response between sympatric cryptic species of the common Indo‐Pacific coral, Pocillopora. In April 2019, prolonged ocean heating occurred at Moorea, French Polynesia. 72% of pocilloporid colonies bleached after 22 days of severe heating (>8°C‐days) at 10 m depth on the north shore fore reef. Colony mortality ranged from 11% to 42% around the island four months after heating subsided. The majority (86%) of pocilloporids that died from bleaching belonged to a single haplotype, despite twelve haplotypes, representing at least five species, being sampled. Mitochondrial (open reading frame) sequence variation was greater between the haplotypes that experienced mortality versus haplotypes that all survived than it was between nominal species that all survived. Colonies >30 cm in diameter were identified as the haplotype experiencing the most mortality, and in 1125 colonies that were not genetically identified, bleaching and mortality increased with colony size. Mortality did not increase with colony size within the haplotype suffering the highest mortality, suggesting that size‐dependent bleaching and mortality at the genus level was caused instead by differences among cryptic species. The relative abundance of haplotypes shifted between February and August, driven by declines in the same common haplotype for which mortality was estimated directly, at sites where heat accumulation was greatest, and where larger colony sizes occurred. The identification of morphologically indistinguishable species that differ in their response to thermal stress, but share a similar ecological function in terms of maintaining a coral‐dominated state, has important consequences for uncovering response diversity that drives resilience, especially in systems with low or declining functional diversity.
... When combined with other localmanagement actions, they can also help buffer global climatic impacts and compensate for critical ecosystem services that are impaired (Duarte et al., 2013;Possingham et al., 2015;Abelson et al., 2016a;Anthony et al., 2017;Darling and Côté, 2018;He and Silliman, 2019). Nevertheless, as climatechange mitigation (reduction of greenhouse gases emission) can take at least decades to affect the Earth's climate (Solomon et al., 2009), there is a growing recognition of the need to identify practical tools to promote adaptation to climate change, so that coastal marine ecosystems can continue to function and provide ecosystem services under a range of future environmental conditions (Webster et al., 2017;Darling and Côté, 2018;Abelson, 2020). We suggest that beyond fostering the services and ecosystem health of degraded coastal marine ecosystems, restoration tools be used to promote adaptation management to cope with future climate-change conditions. ...
... Promoted adaptation can be implemented via two potential directions: "Predict-and-Prescribe" approaches (e.g., "assisted evolution" and "designer reefs;" Mascarelli, 2014;Webster et al., 2017;Darling and Côté, 2018), which attempt to foresee future conditions; and the "Portfolio" approach, which considers the range of uncertainty of future conditions (Schindler et al., 2015;Webster et al., 2017; Figure 2). Although the two strategies are distinct, they may serve as complementary tools. ...
... Promoted adaptation can be implemented via two potential directions: "Predict-and-Prescribe" approaches (e.g., "assisted evolution" and "designer reefs;" Mascarelli, 2014;Webster et al., 2017;Darling and Côté, 2018), which attempt to foresee future conditions; and the "Portfolio" approach, which considers the range of uncertainty of future conditions (Schindler et al., 2015;Webster et al., 2017; Figure 2). Although the two strategies are distinct, they may serve as complementary tools. ...
Coastal marine ecosystems provide critical goods and services to humanity but many are experiencing rapid degradation. The need for effective restoration tools capable of promoting large-scale recovery of coastal ecosystems in the face of intensifying climatic stress has never been greater. We identify four major challenges for more effective implementation of coastal marine ecosystem restoration (MER): (1) development of effective, scalable restoration methods, (2) incorporation of innovative tools that promote climate adaptation, (3) integration of social and ecological restoration priorities, and (4) promotion of the perception and use of coastal MER as a scientifically credible management approach. Tackling these challenges should improve restoration success rates, heighten their recognition, and accelerate investment in and promotion of coastal MER. To reverse the accelerating decline of marine ecosystems, we discuss potential directions for meeting these challenges by applying coastal MER tools that are science-based and actionable. For coastal restoration to have a global impact, it must incorporate social science, technological and conceptual advances, and plan for future climate scenarios.
... predict-and-prescribe strategy). In fact, scientists and managers are now more aware that these approaches do not explicitly address species' long-term persistence because of the inadequate niche representation of the species and the lack of targets that contribute to their adaptive potential by protecting evolutionary processes in wild populations (Hanson et al., 2020;Sgrò et al., 2011;Webster et al., 2017). The limited understanding and articulation of evolutionary principles and processes in conservation efforts can reduce the success of human-mediated interventions Taft et al., 2020). ...
... Here, evolutionary principles have been used to accelerate or slow evolutionary outcomes (Box 1). Thus, it is not surprising that conservation biology should also consider enhancing adaptation (Webster et al., 2017), through the acceleration of naturally occurring processes (i.e. assisted evolution; sensu van Oppen et al., 2015). ...
... genetic manipulation) are potential mechanisms to produce organisms with superior phenotypes (i.e. higher fitness) that promote population persistence under future environmental conditions (e.g. stress-tolerant super corals for warmer and more acidic oceans; van Oppen et al., 2015;Webster et al., 2017). However, the implementation of these approaches require the assessment of risks and the development of monitoring programmes for early warning indicators (e.g. ...
Impacts of climate change are apparent in natural systems around the world. Many species are and will continue to struggle to persist in their current location as their preferred environment changes. Traditional conservation efforts aiming to prevent local extinctions have focused on two aspects that theoretically enhance genetic diversity - population connectivity and population size - through "passive interventions" (such as protected areas and connectivity corridors). However, the exceptionally rapid loss of biodiversity that we are experiencing as result of anthropogenic climate change, has shifted conservation approaches to more "active interventions" (such as rewilding, assisted gene flow, assisted evolution, artificial selection, genetic engineering). We integrate genetic/genomic approaches into an evolutionary biology framework in order to discuss with scientists, conservation managers and decision-makers about the opportunities and risks of interventions that need careful consideration in order to avoid unwanted evolutionary outcomes.
... Climate-relevant conservation for coral reefs requires global climate-change mitigation along with the establishment of marine protected areas that control local-scale threats and consequently reduce the combined impact of global-scale stressors (Tittensor et al. 2019). The dismal outlook for the future of coral reefs has forced conservation efforts into two general approaches: protect the least exposed areas (Beyer et al. 2018) or protect a range of areas subjected to varying exposure regimes (Webster et al. 2017). Identifying a range of areas minimizes uncertainty associated with ecological responses to historical warming and bleaching events (Mumby et al. 2011), and incorporates multiple habitat types subjected to varying levels of exploitation (Webster et al. 2017). ...
... The dismal outlook for the future of coral reefs has forced conservation efforts into two general approaches: protect the least exposed areas (Beyer et al. 2018) or protect a range of areas subjected to varying exposure regimes (Webster et al. 2017). Identifying a range of areas minimizes uncertainty associated with ecological responses to historical warming and bleaching events (Mumby et al. 2011), and incorporates multiple habitat types subjected to varying levels of exploitation (Webster et al. 2017). However, climate conditions are projected to render large areas uninhabitable to corals, and -in light of limited conservation resources -protecting low climate exposure areas will be considered most efficient because they are more likely to survive (Beyer et al. 2018;Mcleod et al. 2019). ...
... However, climate conditions are projected to render large areas uninhabitable to corals, and -in light of limited conservation resources -protecting low climate exposure areas will be considered most efficient because they are more likely to survive (Beyer et al. 2018;Mcleod et al. 2019). This selective identification of the least-exposed sites can be successful only if exposure estimates prove to be correct (Webster et al. 2017) and if exposure is a valid predictor of reef vulnerability. ...
Climate‐driven changes to environmental conditions are driving severe declines of coral reef ecosystems. Current climate vulnerability estimates commonly focus on ocean warming and typically overlook ecological responses or use broad proxies to represent responses, leading to management decisions based on incomplete views of coral reef futures. We explore four underdeveloped aspects of climate vulnerability assessments and make the following recommendations: (1) use climate projections based on changes in global warming as future scenarios in place of the more common emissions scenarios; (2) include available high‐resolution projections for climate variables in addition to thermal stress; (3) combine projected climate stressors accounting for uncertainty in future outcomes; and (4) quantitatively assess historical and project future ecological sensitivity and adaptive capacity of corals to multiple stressors. We demonstrate how this framework can be used to reduce uncertainty in projected climate vulnerability and facilitate targeted investment in managing reefs most likely to endure climatic disturbances.
... Human influence on the biosphere defines the Anthropocene [1] through perturbation of biological resources [2]. Faced with the subsequent ecological crises [3], attention is focusing on the taxa that might persist and the traits promoting success [4][5][6]. Identifying 'winners' [4,7] has become a priority [4,6], but without an historic analogue of biological responses to future conditions with which such determinations can be informed [8], the task is daunting. ...
... Faced with the subsequent ecological crises [3], attention is focusing on the taxa that might persist and the traits promoting success [4][5][6]. Identifying 'winners' [4,7] has become a priority [4,6], but without an historic analogue of biological responses to future conditions with which such determinations can be informed [8], the task is daunting. ...
... Faced with the subsequent ecological crises [3], attention is focusing on the taxa that might persist and the traits promoting success [4][5][6]. Identifying 'winners' [4,7] has become a priority [4,6], but without an historic analogue of biological responses to future conditions with which such determinations can be informed [8], the task is daunting. ...
One response to the coral reef crisis has been human intervention to enhance selection on the fittest corals through cultivation. This requires genotypes to be identified for intervention, with a primary basis for this choice being growth: corals that quickly grow on contemporary reefs might be future winners. To test for temporal stability of growth as a predictor of future performance, genotypes of the coral Porites spp. were grown in common gardens in Mo'orea, French Polynesia. Growth was measured every two to four months throughout 2018, and each period was used as a predictor of growth over the subsequent period. Area-normalized growth explained less than 29% of the variance in subsequent growth, but for biomass-normalized growth this increased to 45-60%, and was highest when summer growth was used to predict autumn growth. The capacity of initial growth to predict future performance is dependent on the units of measurement and the time of year in which it is measured. The final choice of traits to quantify performance must be informed through consideration of the species and the normalization that best capture the information inherent in the biological processes mediating variation in traits values.
... Advocates of evolutionary conservation may have a shorter temporality in mind, more in tune with human action. In addi- In a similar vein, Webster et al. (2017) propose the more holistic approach of "adaptation networks" to tackle uncertainty around future environmental conditions, which, they insist, is poorly addressed by the "predict-and-prescribe paradigm whereby conservation priorities are based on predictors of the responses of species and communities to projected future environmental conditions." They emphasize that a "pick the winners" strategy, which consists in favouring the genotypes and phenotypes anticipated to do best in the future, is risky considering our limited capacity to predict the future, namely to assess the likelihood of each of the many potential outcomes. ...
... Seen under our 4-dimensional framework, their proposal relies on a composite measurement of EP, integrating the maintenance of a diversity of biological options (genes, phenotypes, communities, etc.), the scale and level of connectivity among habitats, and the extent to which the structuring of metapopulations can buffer ecological risks. Here, the vehicles are whole ecosystems or communities, as the authors recognize that "adaptation network explicitly assumes that some aspects of biological diversity will be lost" and that "although individual communities or system elements might be extirpated, the metacommunity and the overall system remain viable" (Webster et al., 2017). While these authors do not explicitly discuss the temporal dimension, a relatively short timescale appears to be involved because their proposal aims to be an alternative to the actions undertaken under the predict-and-prescribe paradigm; these actions are usually set on short timescales (a few generations or decades). ...
... This is because dispersers have better opportunities to track habitat changes and optimal environmental conditions. For the same reason, connectivity between populations can be an indicator of EP (Crooks & Sanjayan, 2006;Ladle & Whittaker, 2011;Webster et al., 2017) even though gene flow can hamper local adaptation (Bridle, Polechová, Kawata, & Butlin, 2010). ...
It is now well admitted among ecologists that the conservation of biodiversity should imply preserving evolutionary processes that will permit its adaptation to ongoing and future environmental changes. This is attested by the ever‐growing reference to the conservation of evolutionary potential in the scientific literature. The impression that one may have when reading papers is that conserving evolutionary potential can only be a good thing, whatever biological system is under scrutiny. However, different objectives, such as maintaining species richness vs. ecosystem services, may express different, when not conflicting, underlying values attributed to biodiversity. For instance, biodiversity can be intrinsically valued, as worth it to be conserved per se, or it can be conserved as a means for human flourishing. Consequently, both the concept of evolutionary potential and the prescriptions derived from the commitment to conserve it remain problematic, due to a lack of explicit mention of the norms associated with different conservation visions. Here we contend that those who advocate for the conservation of evolutionary potential should position their conception along four dimensions: what ‘vehicles’ instantiate the evolutionary potential relevant to their normative commitment; what temporality is involved; how measurable is evolutionary potential, and what degree of human influence is tolerated. We need to address these dimensions if we are to determine why and when the maintenance of evolutionary potential is an appropriate target for the conservation of biodiversity.
... After evaluating the impacts of climate disturbances and the processes that influence thermally stressed corals, West and Salm (2003) recognized 3 major categories of refugia for reefs: avoidance, resistance, and recovery (Figures 1a & 2). Moreover, they and others recognize that this diversity of responses and associated locations creates a potential for strategic conservation science and interventions (Anthony et al., 2020;Camp, 2022;Chollett et al., 2022;Hoegh-Guldberg, Kennedy, et al., 2018;McClanahan & Azali, 2021;McClanahan & Muthiga, 2017;Webster et al., 2017). Therefore, we reviewed the applied work that has evaluated progress toward promoting the diversified portfolio approach recommended to improve the chances for coral adaptation and persistence under rapidly warming ocean conditions. ...
... avoidance to resistance and recovery refugia may not necessarily improve the predictions of specific models, but the process should reduce risk and avoid failures by creating a broader portfolio of models and refugia types that can be actively evaluated to ensure diverse attributes and outcomes (Webster et al., 2017). Another option is to create ensemble models of refugia prediction. ...
Identifying locations of refugia to the thermal stresses of climate change for coral reefs and better managing them is one of the key recommendations for climate change adaptation. Here, we summarize 30 years of applied research and conservation and conclude that currently proposed refugia are highly reliant on excess heat avoidance metrics. A more diverse set of environmental, ecological, and life history variables can identify other types of refugia and lead to the desired diversified portfolio for coral reef conservation. To improve prioritization and site selection decisions, there is a need to: evaluate and validate the predictions of this approach with long-term field data on coral abundance, diversity, and functioning; and identify and safeguard locations displaying resistance to climate exposure or the ability to recover quickly after thermal exposure. We recommend building a portfolio that includes more local ecological and evolutionary context information to identify and conserve a more equal proportion of the three major types of refugia (avoidance, resistance, and recovery); thereby shifting past efforts focused on avoidance towards a diversified risk-spreading portfolio that better manages biodiversity and ecosystem services. Article Impact Statement: Use of environmental and coral life history metrics to identify climate refugia portfolio has yet to diversify sufficiently. This article is protected by copyright. All rights reserved.
... Although the mechanisms contributing to community persistence in an anthropogenically disturbed world are not fully understood, there is growing interest in such 'bright spots' (Cinner et al. 2016;O'Leary et al. 2017) or 'oases' (Guest et al. 2018). There is an urgent need to identify these areas, and to determine the conditions favoring their occurrence in order to prioritize areas for human intervention, an approach known as "predict-and-prescribe" management (Webster et al. 2017). ...
... Under a predict-and-prescribe approach to reef management (sensu Webster et al. 2017), our framework could be used to identify and protect areas where sites are likely to maintain high coral cover despite ongoing anthropogenic disturbances. For example, at regional spatial extents, grid cells with high SST variability and strong light attenuation were more likely to harbor coral oases. ...
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 3,766 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 ten 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 sub‐region. 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 sub‐regional extents. At the regional and sub‐regional 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.
... Likewise, the Farasan Banks were across-basin genetic connectivity, protecting some reefs in all thermal regions is essential to maximize the potential for reefs to help one another recover from future bleaching events, wherever they may strike. Similar strategies emphasizing the importance of linking connectivity and climate heterogeneity in MPA design have been proposed for Belize (Mumby et al., 2011) to develop "adaptation networks" that maximize adaptive capacity and phenotypic acclimatization (Webster et al., 2017). ...
... In addition to the information contained in these databases, we also suggest to include drivers other than thermal stress such as changes in nutrient regimes, which can further exacerbate bleaching responses. Future trajectories of warming over the next decades and century should also be projected to determine whether the proposed MPAs would be located in warming refugia (i.e., projected stable SST) or in areas that may facilitate adaptation (sensu Webster et al., 2017). Following efforts to map coral resilience to thermal stress (e.g., Mumby et al., 2011), mapping the drivers and patterns of coral bleaching over time (such as our Figure 3) as well as including climate projections would guide practitioners in the creation of a bleaching-resilient MPA network. ...
Intensified coastal development is compromising the health and functioning of marine ecosystems. A key example of this is the Red Sea, a biodiversity hotspot subjected to increasing local human pressures. While some marine protected areas (MPAs) were placed to alleviate these stressors, it is unclear whether these MPAs are managed or enforced, thus providing limited protection. Yet, most importantly, MPAs in the Red Sea were not designed using climate considerations, which likely diminish their effectiveness against global stressors. Here, we propose to tailor the design of MPAs in the Red Sea by integrating approaches to enhance climate change mitigation and adaptation. First, including coral bleaching susceptibility could produce a more resilient network of MPAs by safeguarding reefs from different thermal regions that vary in spatiotemporal bleaching responses, reducing the risk that all protected reefs will bleach simultaneously. Second, preserving the mesoscale-eddy-assisted and basin-wide genetic connectivity patterns could further ensure recovery of sensitive populations and maintain species potential to adapt to environmental changes. Finally, protecting mangrove forests in the northern and southern Red Sea that act as major carbon sinks could help offset greenhouse gas emissions. If implemented with multinational cooperation and concerted effort among stakeholders, our portfolio of climate-tailored approaches may help build a network of MPAs in the Red Sea that protects more effectively its coastal resources against escalating coastal development and climate instability. Beyond the Red Sea, we anticipate this study to serve as an example of how to improve the utility of tropical MPAs as climate-informed conservation tools.
... Most attributes of organisms are encoded within their genomes, which determine much of their morphology, biology, behaviour and physiology. High levels of genetic variability and the presence of multiple genotypes within a species can result in functional redundancy that supports species resilience and adaptive capacity under environmental pressures and anomalous conditions 14,15 . Within the context of complex and dynamic systems, genetic diversity is therefore a crucial stabilizing factor. ...
... Such MPA adaptation networks are relevant for instance in coral reef systems 71 , which have been the focus of empirical work to map their adaptation potential 72 . The capacity for a single coral species to inhabit a range of environments characterized by high genetic diversity and on scales of less than 100 m underscores the need for protected areas to be designed with a consideration not only for potential shifts in species distribution across latitudes, but also different water depths 14,73 (Fig. 1). ...
Life has evolved in the ocean for 3.7 billion years, resulting in a rich ‘ocean genome’, the ensemble of genetic material present in all marine biodiversity, including both the physical genes and the information they encode. Rapid advances in sequencing technologies and bioinformatics have enabled exploration of the ocean genome and are informing innovative approaches to conservation and a growing number of commercial biotechnology applications. However, the capacity to undertake genomic research and to access and use sequence data is inequitably distributed among countries, highlighting an urgent need to build capacity, promote inclusive innovation and increase access to affordable technologies.
... This could be done through genomic identification of heritable loci under selection for certain stressors combined with manipulative stress experiments using multiple stressors that test the resilience of genotypes possessing such loci and assess potential trade-offs. Genotypes that perform well can then be cultured for enhanced seeding into restored populations (Figure 2; Weeks et al., 2011;Webster et al., 2017;Fredriksen et al., 2020). Given that such approaches, however, could lead to detrimental trade-offs (maladaptation) and decreased resilience to non-target stressors (Hereford, 2009;Anderson et al., 2014), a portfolio approach whereby assisted adaptation is paired with other approaches including enhancing diversity or connectivity, protecting a wide range of seascapes and minimizing stressors (Webster et al., 2017) may provide more security in uncertain futures. ...
... Genotypes that perform well can then be cultured for enhanced seeding into restored populations (Figure 2; Weeks et al., 2011;Webster et al., 2017;Fredriksen et al., 2020). Given that such approaches, however, could lead to detrimental trade-offs (maladaptation) and decreased resilience to non-target stressors (Hereford, 2009;Anderson et al., 2014), a portfolio approach whereby assisted adaptation is paired with other approaches including enhancing diversity or connectivity, protecting a wide range of seascapes and minimizing stressors (Webster et al., 2017) may provide more security in uncertain futures. ...
Global habitat deterioration of marine ecosystems has led to a need for active interventions to halt or reverse the loss of ecological function. Restoration has historically been a key tool to reverse habitat loss and restore functions, but the extent to which this will be sufficient under future climates is uncertain. Emerging genetic technologies now provide the ability for restoration to proactively match adaptability of target species to predicted future environmental conditions, which opens up the possibility of boosting resistance to future stress in degraded and threatened habitats. As such, the choice of whether to restore to historical baselines or anticipate the future remains a key decision that will influence restoration success in the face of environmental and climate change. Here, we present an overview of the different motives for restoration – to recover or revive lost or degraded habitats to extant or historical states, or to reinforce or redefine for future conditions. We focus on the genetic and adaptive choices that underpin each option and subsequent consequences for restoration success. These options span a range of possible trajectories, technological advances and societal acceptability, and represent a framework for progressing restoration of marine habitat forming species into the future.
... First, persistence in extreme environmental conditions makes them ideal natural laboratories to investigate responses to future ocean conditions as well as resilience hotspots where naturally stress-resistant coral communities can occur. Identifying areas in which populations, species and functional groups are known to be resistant or sensitive to environmental disturbance is critical for designing adaptive marine protected networks (Bates et al., 2019;Webster et al., 2017). Stressresistant coral populations possess traits favourable for survival and persistence under future ocean conditions (Burt et al., 2020;Camp et al., 2018a) and can thus provide opportunities for genetic rescue to coral populations maladapted to various climate change stressors (e.g., Bay et al., 2017;Matz et al., 2018). ...
The worldwide decline of coral reefs has renewed interest in coral communities at the edge of environmental limits because they have the potential to serve as resilience hotspots and climate change refugia, and can provide insights into how coral reefs might function in future ocean conditions. These coral communities are often referred to as marginal or extreme but few definitions exist and usage of these terms has therefore been inconsistent. This creates significant challenges for categorising these often poorly studied communities and synthesising data across locations. Furthermore, this impedes our understanding of how coral communities can persist at the edge of their environmental limits and the lessons they provide for future coral reef survival. Here, we propose that marginal and extreme coral communities are related but distinct and provide a novel conceptual framework to redefine them. Specifically, we define coral reef extremeness solely based on environmental conditions (i.e., large deviations from optimal conditions in terms of mean and/or variance) and marginality solely based on ecological criteria (i.e., altered community composition and/or ecosystem functioning). This joint but independent assessment of environmental and ecological criteria is critical to avoid common pitfalls where coral communities existing outside the presumed optimal conditions for coral reef development are automatically considered inferior to coral reefs in more traditional settings. We further evaluate the differential potential of marginal and extreme coral communities to serve as natural laboratories, resilience hotspots and climate change refugia, and discuss strategies for their conservation and management as well as priorities for future research. Our new classification framework provides an important tool to improve our understanding of how corals can persist at the edge of their environmental limits and how we can leverage this knowledge to optimise strategies for coral reef conservation, restoration and management in a rapidly changing ocean.
... As mentioned above, economically optimal harvest rates could be achieved through input controls, output controls, area-based management, or other measures, depending on each country's unique fishery regulatory frameworks. Ecological connectivity and genetic rescue across coral reefs may boost climate resilience in some reefs that could support fish populations, but diverse and large adaptation networks are necessary to maximize the adaptive capacity of fish and coral species [25]. ...
Small island nations are highly dependent on food from aquatic environments, or blue food, and vulnerable to climate change and global food market price volatility. By 2050, rising populations will demand more food through various protein sources, including from the sea. This study identifies which small island nations can improve food self-sufficiency from the sea by implementing tailored climate-adaptive fisheries governance strategies that adapt to shifting marine resources. We combined projections of seafood demand and local catch under different future scenarios of global carbon emissions and local adaptive fisheries management to estimate potential seafood surpluses or deficits from by 2050 for 31 small island nations worldwide. We find that adapting fisheries management every 10 years could mitigate even worst-case projections of climate change impacts on locally available seafood, building a seafood surplus by 2050 in the Seychelles, Maldives, Cabo Verde, Bahamas, Antigua and Barbuda, Kiribati, PNG, Fiji, FSM, Tuvalu, and Marshall Islands. Strategic financial and capacity investments by the international community could help realize the full potential of food security from the sea for those nations. However, we project deficits in locally caught seafood by 2050 in Comoros, Sao Tome and Principe, and the Grenadines, Trinidad and Tobago, Haiti, Palau, Samoa, Nauru, and the Solomon Islands, regardless of adapting fisheries management. For those nations, we recommend international collaboration that strengthens food security from sources other than the sea coupled with investments in locally sustainable aquaculture. Overall, we find that climate-adaptive fisheries management can benefit a range of the studied small island nations, by supporting both food security goals as well as economic goals of productive fisheries for international trade
... First, persistence in extreme environmental conditions makes them ideal natural laboratories to investigate responses to future ocean conditions as well as resilience hotspots where naturally stress-resistant coral communities can occur. Identifying areas in which populations, species and functional groups are known to be resistant or sensitive to environmental disturbance is critical for designing adaptive marine protected networks (Bates et al., 2019;Webster et al., 2017). Stressresistant coral populations possess traits favourable for survival and persistence under future ocean conditions (Burt et al., 2020;Camp et al., 2018a) and can thus provide opportunities for genetic rescue to coral populations maladapted to various climate change stressors (e.g., Bay et al., 2017;Matz et al., 2018). ...
... Flows of energy (e.g., carbon) and matter (e.g., detrital subsidies) that are critical for the persistence of ecosystems can be achieved by connectivity via animal movement and habitat linkages [41,42]. The flow of genes amongst populations enhances their persistence by promoting genetic diversity that often underpins adaptive potential [6,43,44]. It is important to note that connectivity can also impede conservation goals through the flow of pollutants or the spread of invasive species. ...
Connectivity underpins the persistence of life; it needs to inform biodiversity conservation decisions. Yet, when prioritising conservation areas and developing actions, connectivity is not being operationalised in spatial planning. The challenge is the translation of flows associated with connectivity into conservation objectives that lead to actions. Connectivity is nebulous, it can be abstract and mean different things to different people, making it difficult to include in conservation problems. Here, we show how connectivity can be included in mathematically defining conservation planning objectives. We provide a path forward for linking connectivity to high-level conservation goals, such as increasing species’ persistence. We propose ways to design spatial management areas that gain biodiversity benefit from connectivity.
... This is important for species ability to cope with climate change and diseases (Hoffmann and Sgrò 2011;Carlson et al. 2014;Van Oppen et Al. 2015;Hagedorn and Carter 2016;Webster et al. 2017). The identification of more surviving colonies as potential sperm and egg donors is essential to save D. labyrinthiformis from local extinction. ...
In this study, we evaluated the efficacy of sperm cryopreservation for use in larval-based propagation of Diploria labyrinthiformis and produced offspring that were maintained under controlled conditions. Gametes were collected from colonies in situ in July and August 2017 and 2018. The four largest colonies out of a total of nine appear to be senescent or produce low-quality sperm or eggs. Sperm was cryopreserved for comparison of the effects of storage time on sperm viability. We determined that cry-opreserved sperm from D. labyrinthiformis is viable for at least 13 months for use in in vitro crosses, though their motility is reduced on average by 24% in comparison with fresh sperm. Using frozen sperm to fertilize freshly collected eggs led to successful fertilization, larval yields, settlement and post-settlement survival. In general, these were lower by 23%, 23%, 14% and 8%, respectively, when compared to controls fertilized with fresh sperm. Our results suggest that motility of fresh sperm is not a good indicator of the future fate of larvae because in some cases low motility led to successful settlement. We also found that not all crosses were successful, and that the direction of the cross significantly affects larval yields and settlement. Once symbionts were noticeable within the primary polyps the cryo-recruits were maintained in an ex situ nursery for observation and showed similar survival with respect to recruits produced with fresh sperm. Prior to the 2018 spawning event, Stony Coral Tissue Loss Disease (SCTLD) was detected in the studied colonies and by February 2020 seven of the nine colonies (78%) had succumbed to the disease. The sperm from these colonies was banked in a repository and since then has been used in genetic rescue projects for this species. Thus, we show that cryopreservation is a useful tool in actions designed to recover D. labyrinthiformis and can potentially be applied to other species of corals severely affected by SCTLD or in need of genetic rescue.
... Artificial selection for a single trait also risks creating genetic bottlenecks that erode adaptive capacity (Baums et al., 2019;Sgrò et al., 2011;Shearer et al., 2009). Moreover, selecting genotypes that are better suited to future conditions requires a level of certainty about ecosystem-level responses to warming that may be unrealistic (Schindler & Hilborn, 2015;Webster et al., 2017). However, supplementation activities may also offer other conservation advantages that our analysis did not consider, such as community engagement (Hein et al., 2017;Kittinger et al., 2016), restoration of reefs degraded from non-climate stressors, and a means to augment genetic diversity (Baums et al., 2019). ...
Interest is growing in developing conservation strategies to restore and maintain coral reef ecosystems in the face of mounting anthropogenic stressors, particularly climate warming and associated mass bleaching events. One such approach is to propagate coral colonies ex situ and transplant them to degraded reef areas to augment habitat for reef‐dependent fauna, prevent colonization from spatial competitors, and enhance coral reproductive output. In addition to such ‘demographic restoration’ efforts, manipulating the thermal tolerance of outplanted colonies through assisted relocation, selective breeding, or genetic engineering is being considered for enhancing rates of evolutionary adaptation to warming. While research into such ‘assisted evolution’ strategies has been growing, their expected performance remains unclear. We evaluated potential outcomes of demographic restoration and assisted evolution in climate change scenarios using an eco‐evolutionary simulation model. We found that supplementing reefs with preexisting genotypes (demographic restoration) offers little climate resilience benefits unless input levels are large and maintained for centuries. Supplementation with thermally resistant colonies was successful at improving coral cover at lower input levels, but only if maintained for at least a century. Overall, we found that while demographic restoration and assisted evolution have the potential to improve long‐term coral cover, both approaches had limited impact in preventing severe declines under climate change scenarios. Conversely, with sufficient natural genetic variance and time, corals could readily adapt to warming temperatures, suggesting that restoration approaches focused on building genetic variance may outperform those based solely on introducing heat‐tolerant genotypes.
... Representation and long-term persistence of biodiversity are central to conservation (Margules & Pressey, 2000;Moilanen et al., 2009), but such goals can only be achieved if organisms are able to respond to global changes with geographic range shifts, acclimatization or adaptation (Chevin et al., 2010). As such, conservation plans need to account for the processes shaping biological variability and species' adaptive potential, from ecosystems to genes Wagner & Fortin, 2013;Webster et al., 2017). As humanity enters the UN Decade of Ocean Science for Sustainable Development (2021)(2022)(2023)(2024)(2025)(2026)(2027)(2028)(2029)(2030), the importance of monitoring and maintaining genetic diversity within species to protect the adaptive capacity, community function and resilience within populations is widely acknowledged Thomson et al., 2021), although not necessarily fully accounted for at both national and international scales (Hillebrand et al., 2020). ...
Aim
Intraspecific genetic variation is a key component of biodiversity, with higher diversity indicating greater resilience and population substructuring suggesting unique evolutionary histories. Comparative approaches, in which intraspecific genetic variation is assessed across multiple species, are powerful tools to identify evolutionary hotspots, but are still rarely applied at spatial scales relevant to conservation planning. Here, we use comparative phylogeography to understand patterns and potential drivers of genetic variation within a biodiversity and ocean warming hotspot.
Location
The South African coastline, Indian/Atlantic Oceans.
Methods
A literature search was conducted to obtain mitochondrial DNA cytochrome oxidase c subunit I and cytochrome b sequence data for 17 marine fish and invertebrate species. From these data, we compared averages of haplotype and nucleotide diversity, and within‐region ΦST between four biogeographic provinces in the region. Mixed linear models tested whether environmental variability, habitat preference, or geographic location significantly influence genetic variation.
Results
Average diversity values differed between haplotype and nucleotide diversity, but both broadly displayed highest diversity levels within the South‐West bioregion, which is also a region of high levels of within‐region ΦST. Range in sea surface temperatures (SSTs) was the only significant fixed‐effect term in the haplotype diversity mixed linear models. Mean SST, stability in SSTs since the Mid‐Holocene and position within the species' geographic distribution all had no significant effect on genetic variation.
Main conclusions
Along this coastline characterized by high environmental heterogeneity, we find that variation in temperature is a prominent source of intraspecific variation. Genetic diversity differs between bioregions, but does not display higher levels within the core of each species’ range when assessed across multiple species. With elevated levels of genetic diversity, the South‐West region of the South African coast is highlighted as a conservation priority area, representing both high genetic diversity and differentiation across taxa.
... Biodiversity loss in reef ecosystems associated with environmental (El Niño events and marine heat waves) and anthropogenic (overfishing, pollution or increase in tourism activities) drivers can result in loss of ecological functions and services (Miller et al., 2011;Mouillot et al., 2013). To cope with these disturbances, biological systems respond to new conditions at individual (physiological acclimatization), population (changes in distribution ranges and demography), and community (ecological reorganization) organization levels (Webster et al., 2017). ...
Conservation strategies, such as the establishment of Marine Protected Areas (MPAs), aim to safeguard biodiversity and to promote resilience of ecosystems by increasing their capacity to maintain key functions and processes following disturbance. However, the extent to which ecosystems in MPAs exhibit resilience remains debated. To address this question, we evaluated changes in reef fish species and functional diversity over time in relation to environmental and anthropogenic disturbances at multiple locations in the Gulf of California, Mexico. From 2005 to 2017, we assessed reef fish species richness and abundance in three MPAs: one no-take marine reserve (Cabo Pulmo) and two multi-use marine protected areas (MUMPAs: Espíritu Santo and Loreto). To examine change in functional diversity and composition, we calculated three functional diversity indices – functional richness, functional dispersion and functional originality – using six functional traits (size, mobility, activity, gregariousness, water column position, and diet). Species richness, density and functional diversity were maintained over time (resilience) in the no-take marine reserve. In contrast, MUMPAs showed temporal decline in species richness, which translated into decreases in functional richness and increases in functional dispersion. These differences were also observed at the species level: in Cabo Pulmo, only two ‘loser’ species declined in density, while Espíritu Santo and Loreto showed declines of 12 and 17 species, respectively. The two MUMPAs also shared 9 of the total 22 ‘loser’ species, which are generally abundant and common in the Gulf of California. Density declines were attributed to the combined effect of environmental (sea surface temperature and chlorophyll anomalies) and anthropogenic (fishing, tourism and coastal population density) disturbances. Given the regional decline and the ecological importance of dominant species, long-term decreases in their populations can profoundly modify processes and reef ecosystem services in this region. Thus, local management strategies should be implemented to try to reverse the observed recent decline in fish diversity in MUMPAs.
... This is further aligned with theory, whereby coastal ecosystems facing extreme levels of climate stress-like coral reefs-can have the most successful outcomes from local conservation in climate change refugia, although managing local stressors outside of refugia can also help buffer essential recovery following climate disturbances ( 2019). Here, we show that the occurrence of local pressures is similar between refugia and nonrefugia locations, providing an opportunity for efforts to mitigate local pressures to scale up beyond climate refugia and to include nonrefugia locations or disturbed reefs in a broader seascape approach to adaptation and resilience (Darling et al., 2019;Webster et al., 2017). From local to global scales, our results provide information that can be quickly integrated into ongoing coral reef conservation efforts, for example to prioritize threat mitigation efforts for reefs facing high pressures, or to maintain sustainable use through precautionary management for reefs with lower pressures (Campbell et al., 2020). ...
As human activities on the world's oceans intensify, mapping human pressure is essential to develop appropriate conservation strategies and prioritize investments with limited resources. Here, we map six human (nonclimatic) pressures on coral reefs using the latest quantitative data on fishing, water pollution (nitrogen and sediments), coastal population, industrial development, and tourism. Using a percentile approach to rank different stressors, we identify the top‐ranked local pressure and estimate a cumulative pressure index for 54,596 global coral reef pixels at 0.05° (∼5 km) resolution. We find that coral reefs are exposed to multiple intense local pressures: fishing and water pollution (nutrients and sediments) are the most common top‐ranked pressures worldwide (in 30.8% and 32.3% of reef cells, respectively), although each pressure was ranked as a top pressure in some locations. We also find that local pressures are similar inside and outside a proposed global portfolio of coral reef climate refugia, suggesting that even potential climate refugia have high levels of local human pressure that require effective management. Our findings and datasets provide the best available information that can ensure local pressures are effectively managed across the world's coral reefs.
... Overall, these results illustrate how genomic tools can be used to inform conservation, and that species-specific differentiation and local adaptation patterns require appropriate management strategies (Nielsen et al. 2021). In a general framework, the representativity of spatially defined populations subject to different local adaptation could be included in MPA coverage targets to preserve a portfolio of potential adaptations and maximize the preservation of genetic diversity (Webster et al. 2017, Xuereb et al. 2020). ...
Human activities and their resulting pressures on natural ecosystems are altering biodiversity and induce a loss of species, population and genetic diversity. Across the marine realm, networks of marine protected areas (MPAs) are increasingly established to alleviate pressures and restore biodiversity and ecosystem processes. Yet, the mechanisms by which MPAs can preserve biodiversity and sustain fisheries are still unclear, though they are essential to ensure the success and implementation of MPAS in order to reach the 30% protection target. My PhD uses Next-Generation Sequencing (NGS) tools to study biodiversity patterns of Mediterranean fishes at three levels – communities, populations and genes – and to better guide their conservation under increasing climate warming and fishing pressure.Understanding the effect of MPAs on fish communities requires the detection of a wide range of species. Yet, visual censuses only detect a fraction of biodiversity. I apply environmental DNA (eDNA) metabarcoding to study the diversity of fish communities in six Mediterranean MPAs. This approach allows the detection and identification of species from the thousands of sequences found in a single water sample. The results highlight a new conservation paradox: MPAs are less species-rich than their surroundings. However, they host different species assemblages compared to fished areas thus increasing regional diversity. This difference is mainly driven by species often overlooked by conventional visual methods but detected with eDNA: cryptobenthic, pelagic, and rare fishes.Biodiversity also depends on the connectivity between populations through the successful dispersal of propagules and individuals, leading to gene flow. I investigate the Mediterranean-wide connectivity of two fishes, the striped red mullet (Mullus surmuletus) and white seabream (Diplodus sargus). I develop a spatial graph approach that extends propagule dispersal networks over multiple generations to better match the spatio-temporal scale of genetic connectivity. Comparing these new estimates with the analysis of 1,153 neutral SNPs from 47 putative populations reveals how mullet populations achieve high levels of gene flow through multi-generational stepping-stone dispersal. Kinship estimations also reveal that seabream is capable of exceptional long-distance dispersal (about 2,000km) in only two or three generations.Such high levels of gene flow however can diminish population structure and impede local adaptation. To better understand these mechanisms, I analyse 823 individuals genotyped for 704 highly differentiated (i.e. outlier) SNPs potentially under selection. I can thus disentangle the relative influence of spatial distance, larval dispersal and environmental conditions - which are expected to change under climate change - on the genomic structure of both species. These analyses reveal that temperature plays a significant role in the genomic structure of mullet and seabream, allowing the detection of genes potentially involved in local adaptation.By combining powerful genomic and statistical tools, this thesis deciphers new patterns of biodiversity with novel implications for conservation. The results highlight how MPAs can preserve fish biodiversity and community structure in the face of fishing pressure. They also suggest how networks of well-connected MPAs could ensure the persistence and adaptive potential of populations facing climate change.
... However, although data on current and future ecological processes are critical when identifying protected areas, climate change and its impacts are rarely incorporated into spatial conservation prioritizations(Álvarez-Romero et al., 2018;Jones et al., 2016;Reside et al., 2018;.Although marine protected areas help species within their boundaries adapt to a changing climateMicheli et al., 2012;C. M. Roberts et al., 2017;Webster et al., 2017), species shift their biogeographic distributions to track their preferred thermal niches as climate changes ...
Species are rapidly shifting poleward as the climate warms, presenting a key challenge in ocean conservation. This thesis tackles a central question in marine ecology: how can climate change be included in conservation science, especially considering the three-dimensional nature of the ocean? To this end, this thesis presents novel research on the impacts of climate change on biodiversity at different depths in the ocean and how this can be included in marine spatial planning. With the building momentum towards protecting 30% of the ocean by 2030, this thesis helps to advance climate-smart conservation science.
... Furthermore, in situ nursery sites that promote faster growth would provide obvious logistical benefits, leading to shorter residence times for individuals and greater yields for outplanting. Assisted gene flow using climate change-resistant genets could complement traditional conservation measures such as marine protected areas, which could provide favorable habitat for stress-resistant outplants, and in coordination with less directed approaches [e.g., adaptation networks (71)] to preserve genetic diversity. Restoration targets may include reefs damaged directly by human activity (e.g., ship groundings, dredging, etc.) or indirectly via bleaching-related mortality. ...
Significance
Ocean warming has caused catastrophic losses of corals on reefs worldwide and is intensifying faster than the adaptive rate of most coral populations that remain. Human interventions, such as propagation of heat-resistant corals, may help maintain reef function and delay further devastation of these valuable ecosystems as society confronts the climate crisis. However, exposing adult corals to a complex suite of new environmental conditions could lead to tradeoffs that alter their heat stress responses, and empirical data are needed to test the utility of this approach. Here, we show that corals transplanted to novel reef conditions did not exhibit changes in their heat stress response or negative fitness tradeoffs, supporting the inclusion of this approach in our management arsenal.
... Nevertheless, promoting natural adaptation becomes one critical management objective under climate change that echoes those preferring to rely on the inherent adaptive capacity of ecosystems to shape adapted forests. Areas originally devoted to biodiversity conservation would be candidates for a natural adaptation approach (sensu Bolte et al. [54]) that intentionally refrains from active control over adaptive processes [54,55]. In some cases, this approach may have a greater social acceptability than proactive interventions [51], but acceptability may quickly change if climate change threatens the provisioning of ecosystem services or social security, such as, for example, the increasing frequency and intensity of wildland fires [56]. ...
Climate change is threatening our ability to manage forest ecosystems sustainably. Despite strong consensus on the need for a broad portfolio of options to face this challenge, diversified management options have yet to be widely implemented. Inspired by functional zoning, a concept aimed at optimizing biodiversity conservation and wood production in multiple-use forest landscapes , we present a portfolio of management options that intersects management objectives with forest vulnerability to better address the wide range of goals inherent to forest management under climate change. Using this approach, we illustrate how different adaptation options could be implemented when faced with impacts related to climate change and its uncertainty. These options range from establishing ecological reserves in climatic refuges, where self-organizing ecological processes can result in resilient forests, to intensive plantation silviculture that could ensure a stable wood supply in an uncertain future. While adaptation measures in forests that are less vulnerable correspond to the traditional functional zoning management objectives, forests with higher vulnerability might be candidates for transformative measures as they may be more susceptible to abrupt changes in structure and composition. To illustrate how this portfolio of management options could be applied, we present a theoretical case study for the eastern boreal forest of Canada. Even if these options are supported by solid evidence, their implementation across the landscape may present some challenges and will require good communication among stakeholders and with the public.
... Critically for conservation, this indicates that adaptive divergence of small populations can occur quickly following fragmentation (Brauer et al., 2017) and that even very recently isolated populations may harbour novel adaptive diversity. It is therefore important to build evolutionary resilience by facilitating genetic exchange among isolated populations to restore natural evolutionary processes and maintain species-level genetic variation, potentially valuable under a range of future selection regimes (Webster et al., 2017;Weeks et al., 2016). ...
Anthropogenic habitat fragmentation is often implicated as driving the current global
extinction crisis, particularly in freshwater ecosystems. The genetic signal of recent population isolation can be confounded by the complex spatial arrangement
of dendritic river systems. Consequently, many populations may presently be managed separately based on an incorrect assumption that they have evolved in isolation. Integrating landscape genomics data with models of connectivity that account
for landscape structure, we show that the cumulative effects of multiple in-stream
barriers have contributed to the recent decline of a freshwater fish from the Murray–
Darling Basin, Australia. In addition, individual-based eco-evolutionary simulations
further demonstrate that contemporary inferences about population isolation are
consistent with the 160-year time frame since construction of in-stream barriers
began in the region. Our findings suggest that the impact of very recent fragmentation may be often underestimated for freshwater biodiversity. We argue that proactive conservation measures to reconnect many riverine populations are urgently
needed.
... At the same time, the number of species in the Persian Gulf is limited (about 70 in total). Hence, by choosing a relatively narrow set of expected "winners", this approach risks eroding global biodiversity [60]. It is therefore essential to take a balanced approach to species selection, which includes first, broad genetic diversity, and second, corals with a variety of specific traits (for example, thermal tolerance, high fecundity, disease tolerance) and from a variety of habitats, shown to contribute to coral performance [61]. ...
Global change causes widespread decline of coral reefs. In order to counter the anticipated disappearance of coral reefs by the end of this century, many initiatives are emerging, including creation of marine protected areas (MPAs), reef restoration projects, and assisted evolution initiatives. Such efforts, although critically important, are locally constrained. We propose to build a "Noah's Ark" biological repository for corals that taps into the network of the world's public aquaria and coral reef scientists. Public aquaria will serve not only as a reservoir for the purpose of conservation, restoration, and research of reef-building corals but also as a laboratory for the implementation of operations for the selection of stress-resilient and resistant genotypes. The proposed project will provide a global dimension to coral reef education and protection as a result of the involvement of a network of public and private aquaria.
... Erõs et al. (2018) provide an example of how spatial prioritization may allow planners to effectively resolve tradeoffs between biodiversity conservation and other ecosystem services during landscape planning. In light of the uncertainty contained within projections of which species may win or lose, Webster et al. (2017) argue for taking a portfolio-based approach to conservation planning that emphasizes developing large, diverse networks that maximize the adaptive capacity of the species and system. Ultimately, this collective set of findings highlights the need to consider both the direct and indirect effects of any management strategy to the broader ecosystem. ...
How anticipated climate change might affect long-term outcomes of present-day agricultural conservation practices remains a key uncertainty that could benefit water quality and biodiversity conservation planning. To explore this issue, we forecasted how the stream fish communities in the Western Lake Erie Basin (WLEB) would respond to increasing amounts of agricultural conservation practice (ACP) implementation under two IPCC future greenhouse gas emission scenarios (RCP4.5: moderate reductions; RCP8.5: business-as-usual conditions) during 2020–2065. We used output from 19 General Circulation Models to drive linked agricultural land use (APEX), watershed hydrology (SWAT), and stream fish distribution (boosted regression tree) models, subsequently analyzing how projected changes in habitat would influence fish community composition and functional trait diversity. Our models predicted both positive and negative effects of climate change and ACP implementation on WLEB stream fishes. For most species, climate and ACPs influenced species in the same direction, with climate effects outweighing those of ACP implementation. Functional trait analysis helped clarify the varied responses among species, indicating that more extreme climate change would reduce available habitat for large-bodied, cool-water species with equilibrium life-histories, many of which also are of importance to recreational fishing (e.g., northern pike, smallmouth bass). By contrast, available habitat for warm-water, benthic species with more periodic or opportunistic life-histories (e.g., northern hogsucker, greater redhorse, greenside darter) was predicted to increase. Further, ACP implementation was projected to hasten these shifts, suggesting that efforts to improve water quality could come with costs to other ecosystem services (e.g., recreational fishing opportunities). Collectively, our findings demonstrate the need to consider biological outcomes when developing strategies to mitigate water quality impairment and highlight the value of physical-biological modeling approaches to agricultural and biological conservation planning in a changing climate.
... Advocates of assisted migration argue that humans have been translocating plants and animals throughout history (Vitt et al. 2010) and point out that assisted migration has been successfully applied in the past without negative repercussions (Schlaepfer et al. 2009;Willis et al. 2009). Despite its proponents, assisted migration remains a contentious conservation action (e.g., McLachlan et al. 2007;Gallagher et al. 2015;Webster et al. 2017). Experts identify 3 primary risks. ...
Assisted migration is a controversial conservation measure that aims to protect threatened species by moving part of their population outside its natural range. Although this could save species from extinction, it also introduces a range of risks. The magnitude of the threat to recipient ecosystems has not been investigated quantitatively, despite being the most common criticism leveled at the action. We used an ensemble modeling framework to estimate the risks of assisted migration to existing species within ecosystems. With this approach, we calculated the consequences of an assisted migration project across a very large combination of translocated species and recipient ecosystems. We predicted the probability of a successful assisted migration and the number of local extinctions would result from establishment of the translocated species. Using an ensemble of
1.5
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simulated 15-species recipient ecosystems, we estimated that translocated species will successfully establish in 83% of cases if introduced to stable, high-quality habitats. However, assisted migration projects were estimated to cause an average of 0.6 extinctions and 5% of successful translocations triggered 4 or more local extinctions. Quantifying the impacts to species within recipient ecosystems is critical to help managers weigh the benefits and negative consequences of assisted migration.
... Sacrificing the Future of Coral Reefs 2016b; He and Silliman, 2019); (iii) Restoration of degraded and damaged reefs Abelson et al., 2016b); and (iv) Promotion of reef resilience and adaptation to the changing conditions (from regional to global), notably climate change effects (e.g. Mumby and Anthony, 2015;Webster et al., 2017;Anthony et al., 2017;Mumby, 2017b;Roberts et al., 2017;Cinner et al., 2018;Darling et al., 2019;He and Silliman, 2019;NAP, 2019a, b;Walsworth et al., 2019). For management efforts to produce tangible results, the human dimension needs to be integrated into all four management directions to establish adaptive social-ecological systems (Kittinger et al., 2012;Abelson et al., 2016a;Bodin, 2017;Darling et al., 2019). ...
Following a series of mass-bleaching events that have seriously degraded coral reefs, notably the Great Barrier Reef of Australia, a common narrative is now dominating the discourse, according to which "the only sure way to save the world's coral reefs is climate change mitigation". However, climate change is not a sole stressor. Most coral reefs around the world are threatened by a myriad of local stressors, including overfishing, destructive fishing, untreated sewage, agriculture effluents (nutrients and pesticides), and siltation due to deforestation. Reefs will not survive the severe effects of this plethora of stressors while waiting until we mitigate climate change. In order to safeguard reefs, we need to adopt a new narrative - "there are diverse ways in which we can improve the chances of saving coral reefs" - by acting now to: (i) improve their local protection and marine protected area networks, (ii) alleviate their critical local stressors, (iii) restore degraded and damaged reefs, and (iv) promote reef resilience and adaptation (e.g. adaptation networks, assisted evolution) to the changing conditions, notably climate change effects. It is time for us to move on from the impractical goals of the climate change narrative ("interventions beyond our field of expertise") to building up resilience and adaptation of social-ecological systems of coral reefs. © 2019 International Council for the Exploration of the Sea 2019. All rights reserved. For permissions, please email: [email protected]
... As such, basal and phenotypic plasticity traits play a pivotal role in invasive species' successful spread and establishment in new environments. Indeed, fitness and survival may be dependent on adjusting to novel environmental conditions through physiological acclimatisation/acclimation and genetic adaptation (Webster et al., 2017;Castañeda et al., 2019;Griffith et al., 2019). It is increasingly being documented that invasive species may particularly have flexible life history traits (Agosta et al., 2018), and this potentially explains their success under heterogeneous environments. ...
South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating invasive global insect pest of tomato, Solanum lycopersicum (Solanaceae). In nature, pests face multiple overlapping environmental stressors, which may significantly influence survival. To cope with rapidly changing environments, insects often employ a suite of mechanisms at both acute and chronic time-scales, thereby improving fitness at sub-optimal thermal environments. For T. absoluta, physiological responses to transient thermal variability remain under explored. Moreso, environmental effects and physiological responses may differ across insect life stages and this can have implications for population dynamics. Against this background, we investigated short and long term plastic responses to temperature of T. absoluta larvae (4th instar) and adults (24–48 h old) field populations. We measured traits of temperature tolerance vis critical thermal limits [critical thermal minima (CTmin) and maxima (CTmax)], heat knockdown time (HKDT), chill coma recovery time (CCRT) and supercooling points (SCP). Our results showed that at the larval stage, Rapid Cold Hardening (RCH) significantly improved CTmin and HKDT but impaired SCP and CCRT. Heat hardening in larvae impaired CTmin, CCRT, SCP, CTmax but not HKDT. In adults, both heat and cold hardening generally impaired CTmin and CTmax, but had no effects on HKDT, SCP and CCRT. Low temperature acclimation significantly improved CTmin and HKDT while marginally compromising CCRT and CTmax, whereas high temperature acclimation had no significant effects on any traits except for HKDT in larvae. Similarly, low and high temperature acclimation had no effects on CTmin, SCPs and CTmax, while high temperature acclimation significantly compromised adult CCRT. Our results show that larvae are more thermally plastic than adults and can shift their thermal tolerance in short and long timescales. Larval plasticity advantage over adults reported here suggest asymmetrical ecological role of the larva relative to adults in facilitating T. absoluta invasion.
Despite great promise for understanding the impacts and extent of climate change on aquatic animals, their species, and ecological communities, it is surprising that tracking tools, like biotelemetry and biologging devices, have not been extensively used to understand climate change or develop and evaluate potential interventions that may forestall or mitigate its effects. In this review, we provide an overview of methodologies and study designs that leverage available tracking tools to investigate aspects of climate change on aquatic ecosystems. Key interventions to protect aquatic life from the impacts of climate change, including habitat restoration, protected areas, conservation translocations, mitigations against interactive effects of climate change, and simulation of future scenarios can all be greatly facilitated by using electronic tagging and tracking. We anticipate that adapting study designs (e.g. use of replicated ponds, randomized control trials, physiologging) to effectively use tracking will greatly enhance our understanding of climate change and its impacts on aquatic ecosystems, hopefully also facilitating research into effective solutions and interventions against the most extreme and acute impacts.
Over recent years the number of studies on the assisted evolution of corals has increased dramatically, with most able to demonstrate enhanced tolerance of the coral holobiont (that is, the cnidarian host, the photosynthetic symbionts and other microbes), (Drury et al., 2022 and more). Yet significant knowledge gaps exist in our fundamental understanding of how coral heat tolerance evolves and the efficacy or effect size of interventions that aim to improve this process. Further, the technologies or strategies to implement these approaches at scale are largely absent in both restoration and adaptation contexts. As a result, resources including funding and time cannot be applied effectively and strategically. To address these issues, we evaluated gaps in knowledge about coral thermal adaptation and the interventions used to enhance their tolerance and adaptation to global heating.
A R T I C L E I N F O ey ords Multispecies livelihoods Wildlife-human conflict Ecosystem-based fisheries management Posthumanism Animal ethics A B S T R A C T The sustainability paradigm in fisheries management is held legitimate to ensure food security and the ability for future generations. Conventional management principles and scientific methods may objectify data and nonhuman subjects in these practices. This paper introduces posthuman philosophies to Ecosystem-Based Fisheries Management (EBFM), and it explore the case of the Columbia sea lion in the Pacific Northwest United States. We offer a multispecies livelihoods perspective as an applied approach to wildlife-human conflict by adhering to the biocultural hierarchies of the region. An era of ecological rehabilitation should focus on coadaptation between human and nonhuman peoples, including that of the Columbia sea lion. Our findings are supported by a 12-month multispecies ethnographic design. They provide robust insight to the phenomenology of salmon-sea lion-human relations. A posthuman multispecies livelihoods approach offers a way forward for fisheries governance and contends that the rights, welfare, and agency of nonhuman individuals and their habitats must be foregrounded.
The real‐world application of climate change adaptation practices in terrestrial wildlife conservation has been slowed by a lack of practical guidance for wildlife managers. Although there is a rapidly growing body of literature on the topic of climate change adaptation and wildlife management, the literature is weighted towards a narrow range of adaptation actions and administrative or policy recommendations that are typically beyond the decision space and influence of wildlife professionals. We developed a menu of tiered adaptation actions for terrestrial wildlife management to translate broad concepts into actionable approaches to help managers respond to climate change risks and meet desired management goals. The menu includes actions related to managing wildlife populations as well as managing wildlife habitat. We designed this resource to be used with the Adaptation Workbook, a structured decision‐support tool for climate adaptation. We describe real‐world examples in which managers have used the Wildlife Adaptation Menu to integrate climate adaptation considerations into wildlife management and conservation projects. Our examples illustrate how a comprehensive and structured menu of adaptation approaches can help managers brainstorm specific actions and more easily and clearly communicate the intent of their climate adaptation efforts. We present a structured, comprehensive menu of climate change adaptation strategies and approaches for managers of terrestrial wildlife. This menu can help managers define specific actions to implement and communicate the intent of their actions.
Climate change and ENSO have triggered five mass coral bleaching events on Australia’s Great Barrier Reef (GBR), three of which occurred in the last 5 years.1, 2, 3, 4, 5 Here, we explore the cumulative nature of recent impacts and how they fragment the reef’s connectivity. The coverage and intensity of thermal stress have increased steadily over time. Cumulative bleaching in 2016, 2017, and 2020 is predicted to have reduced systemic larval supply by 26%, 50%, and 71%, respectively. Larval disruption is patchy and can guide interventions. The majority of severely bleached reefs (75%) are predicted to have experienced an 80%–100% loss of larval supply. Yet restoration would not be cost-effective in the 2% of such reefs (∼30) that still experience high larval supply. Managing such climate change impacts will benefit from emerging theory on the facilitation of genetic adaptation,⁶,⁷ which requires the existence of regions with predictably high or low thermal stress. We find that a third of reefs constitute warm spots that have consistently experienced bleaching stress. Moreover, 13% of the GBR are potential refugia that avoid significant warming more than expected by chance, with a modest proportion (14%) within highly protected areas. Coral connectivity is likely to become increasingly disrupted given the predicted escalation of climate-driven disturbances,⁸ but the existence of thermal refugia, potentially capable of delivering larvae to 58% of the GBR, may provide pockets of systemic resilience in the near-term. Theories of conservation planning for climate change will need to consider a shifting portfolio of thermal environments over time.
Okyanus ve denizlerinizdeki en hızlı büyüyen çevresel tehdit haline gelen plastik kirliliği
gezegenimizin iklimi için de ciddi bir tehdit oluşturmaktadır. Çok büyük bir kısmı fosil
yakıtlardan yapılan plastikler ham maddenin çıkarılmasından, rafinerizasyonuna, geri
dönüşümünden doğada son bulmasına kadar yaşam döngüsünün her aşamasında sera gazı
emisyonuna yol açmaktadır. Plastik üretiminin önümüzdeki yıllarda katlanarak artacağı
göz önünde bulundurulduğunda, plastikten kaynaklanan sera gazı emisyonlarının küresel
sıcaklık artışını 1,5℃'nin altında tutma kabiliyetimizi tehlikeye attığı düşünülmektedir.
Küresel ölçekte plastiklerin üretiminin kontrol altına alınması, plastik atıkların işlenmesi
ve bertarafının iyileştirilmesi ve (mikro) plastiklerin iklim üzerindeki etkisinin
değerlendirilmesi önem arz etmektedir.
O objetivo deste trabalho foi apresentar uma revisão bibliográfica sobre os principais impactos que os ecossistemas agrícolas e naturais vêm sofrendo com a ocorrência das mudanças climáticas, e então expor algumas estratégias de mitigação dos impactos e da adaptação destes ecossistemas às mudanças. Dentre as estratégias, podem-se citar o uso de modelos de simulação de culturas como suporte ao conhecimento e tomadas de decisão, o uso de genes de plantas adaptadas às alterações climáticas no melhoramento genético, e o uso de políticas públicas voltadas ao desenvolvimento sustentável.
Global biodiversity is in unprecedented decline and on‐the‐ground solutions are imperative for conservation. Although there is a large volume of evidence related to climate change effects on wildlife, research on climate adaptation strategies is lagging. To assess the current state of knowledge in climate adaptation, we conducted a comprehensive literature review and evaluated 1,346 peer‐reviewed publications for management recommendations designed to address the consequences of climate change on wildlife populations. From 509 publications, we identified 2,306 recommendations and employed both qualitative and quantitative methods for data analysis. Although we found an increase in the volume and diversity of recommendations since 2007, a focus on protected areas (26%, 596 of 2,306 recommendations) and the non‐reserve matrix (12%, 276 of 2,306 recommendations) remained prominent in the climate adaptation literature. Common concepts include protected areas, invasive species, ecosystem services, adaptive management, stepping stones, assisted migration, and conservation easements. In contrast, only 1% of recommendations focused on reproduction (n = 26), survival (n = 14), disease (n = 26), or human‐wildlife conflict (n = 24). Few recommendations reflected the potential for local‐scale management interventions. We demonstrate limited advancement in preparing natural resource managers in climate adaptation at local, management‐relevant scales. Additional research is needed to identify and evaluate climate adaptation strategies aimed at reducing the vulnerability of wildlife to contemporary climate change. © 2020 The Wildlife Society. Although peer‐reviewed recommendations to inform climate adaptation are rapidly increasing, protected area management remains the prominent focus in the scientific literature. Researchers need to address the deficit of local‐scale, population‐based recommendations for climate adaptation for terrestrial wildlife.
Urgent action is needed to prevent the demise of coral reefs as the climate crisis leads to an increasingly warmer and more acidic ocean. Propagating climate change resistant corals to restore degraded reefs is one promising strategy; however, empirical evidence is needed to determine if resistance is retained following transplantation within or beyond a coral’s natal reef. Here we assessed the performance of bleaching-resistant individuals of two coral species following reciprocal transplantation between environmentally distinct reefs (low vs high diel variability) to determine if stress resistance is retained following transplantation. Critically, transplantation to either environment had no influence on coral bleaching resistance, indicating that this trait was relatively fixed and is thus a useful metric for selecting corals for reef restoration within their native range. In contrast, growth was highly plastic, and native performance was not predictive of performance in the novel environment. Coral metabolism was also plastic, with cross transplants of both species matching the performance of native corals at both reefs within three months. Coral physiology (autotrophy, heterotrophy, and metabolism) and overall fitness (survival, growth, and reproduction) were higher at the reef with higher flow and fluctuations in diel pH and dissolved oxygen, and did not differ between native corals and cross-transplants. Conversely, cross-transplants at the low-variability reef had higher fitness than native corals, thus increasing overall fitness of the recipient population. This experiment was conducted during a non-bleaching year, which suggests that introduction of these bleaching-resistant individuals will provide even greater fitness benefits to recipient populations during bleaching years. In summary, this study demonstrates that propagating and transplanting bleaching-resistant corals can elevate the resistance of coral populations to ocean warming while simultaneously maintaining reef function as the climate crisis worsens.
The availability of genomic data for an increasing number of species makes it possible to incorporate evolutionary processes into conservation plans. Recent studies have demonstrated how genetic data can inform spatial conservation prioritization (SCP), but focused on metrics of diversity and distinctness derived primarily from neutral genetic datasets. Identifying adaptive genetic markers can provide important information regarding the capacity for populations to adapt to environmental change. Yet, the effect of including metrics based on adaptive genetic data into SCP, and how they compare to more widely‐used neutral genetic metrics, has not been explored. We performed SCP for the coastal region of British Columbia (BC), Canada using existing genomic data on a commercially exploited species, the California sea cucumber (Parastichopus californicus). Using a RAD‐seq dataset for 717 P. californicus individuals across 24 sampling locations, we identified putatively adaptive (i.e., ‘candidate’) single nucleotide polymorphisms (SNPs) based on genotype‐environment associations with seafloor temperature. We calculated various metrics for both neutral and candidate SNPs and compared SCP outcomes using independent metrics and combinations of metrics. Priority areas varied depending on whether neutral or candidate SNPs were used, and also depending on the specific metric used. For example, targeting sites with a high frequency of warm temperature‐associated alleles to support persistence under future warming prioritized areas in the southern coastal region. In contrast, targeting sites with high expected heterozygosity at candidate loci to support persistence under future environmental uncertainty prioritized areas in the north. When combining metrics, all scenarios generated intermediate solutions, protecting sites that span latitudinal and thermal gradients. Our results demonstrate that distinguishing between neutral and adaptive markers can affect conservation solutions and emphasize the importance of defining objectives when choosing among various genomic metrics for SCP. Article Impact Statement: Genomic metrics derived from neutral and adaptive genomic data result in different spatial conservation prioritization solutions. This article is protected by copyright. All rights reserved
Climate change is redistributing terrestrial and marine biodiversity and altering fundamental ecological interactions. To adequately conserve biodiversity and promote its long-term persistence, protected areas should account for the ecological implications of species redistribution. Data paucity across many systems means that achieving this goal requires generic metrics that represent likely responses of multiple taxa to climate change. Climate velocity is one such metric, reflecting potential species range shifts at a generic level. Here, we explore four approaches to incorporating climate velocity metrics into the design of protected areas using the Mediterranean Sea as an illustrative example. Our methods are designed to meet two climate-smart planning objectives: 1) protect climate refugia by selecting slow-moving climate velocity areas, and 2) maintain the capacity of ecological systems to adapt by representing a suite of climate-velocity trajectory classes. We found that incorporating climate velocity as a cost measure in Marxan is the best approach for selecting slower-moving areas, which are good indicators of climate refugia. However, this approach fails to accommodate socio-economic cost data, and is probably impractical. Incorporating climate velocity as a boundary or as a feature provides both selection of slower-moving areas and solutions with lower socio-economic cost. Finally, we were able to design cost-effective networks of protected areas representing a suite of climate-velocity trajectories classes, which have the potential to help species adapt to a changing climate. This work presents simple and practical ways of including climate velocity in conservation plans on land and in the ocean to achieve the key climate-smart objectives of protecting climate refugia and enhancing ecological resilience.
This study aimed at analyzing the current status and further needs of ecological
information which is provided with the civil servants in the process of climate change adaptation planning in ecosystem sector and at providing suggestions for future development of ecological knowledge on climate change. Therefore, we conducted a questionary survey titled as “the knowledge-base and information needs for climate change adaptation in ecosystem sector” with the civil servants who are engaged with adaptation practices in the ecology related divisions in 17 regional local governments (RLG) and the affiliated basic local governments (BLG) in Korea. As a result, the characteristics of ecological information which is applied in public practices was analyzed and strategies for improved utilization was suggested. 75% of the respondents (RLG 85% and BLG 72%) were aware of the relativeness between the existence and utilization of ecological information and the execution of climate adaptation practices in ecosystem sector. They were agreed with the necessity of ecological information not only in adaptation practices but also overall affairs in the ecological related division in the local government (RLG 82% and BLG 72%). The current situation of utilizing ecological information which is produced from central or local government to civil affairs were only represented as 64 persons (28%) in RLG and 42 persons (18%) in BLG. One of the major obstacles that the respondents confront with when applying ecological information to public practices was deficit of prior knowledge on the ecological information itself, such as awareness of the characteristics of ecological information and the link with public affairs for adaptation plans.
Therefore, delivering current knowledge and ecological information on climate change by
educational and promotional method is an urgent priority to the civil servant. The future needs on ecological information for local government servants were deduced as basic information on local ecosystem and applied knowledge on local development to meet the biodiversity conservation and ecosystem services at the same time. The respondents expected not only the specific guidelines for using ecological information to apply on the adaptation plans in the relevant divisions of the local governments but also the institution where the usage activation of ecological information would be operated and managed to enhance the information utilizing structure in the local government. In the nation-wide, the capacity of local governments should be enhanced with adaptation knowledge and the application of appropriate information to the public practices by central government’s aiding with the better quality of information, its public promotion, and the applicability to civil affairs.
Coral bleaching caused by rising sea temperature is a primary cause of coral reef degradation. However, bleaching patterns often show significant spatial variability, therefore identifying locations where local conditions may provide thermal refuges is a high conservation priority. Coral bleaching mortality often diminishes with increasing depth, but clear depth zonation of coral communities and putative limited overlap in species composition between deep and shallow reef habitats has led to the conclusion that deeper reef habitats will provide limited refuge from bleaching for most species. Here, we show that coral mortality following a severe bleaching event diminished sharply with depth. Bleaching-induced mortality of Acropora was approximately 90% at 0-2m, 60% at 3-4 m, yet at 6-8m there was negligible mortality. Importantly, at least two-thirds of the shallow-water (2-3 m) Acropora assemblage had a depth range that straddled the transition from high to low mortality. Cold-water upwelling may have contributed to the lower mortality observed in all but the shallowest depths. Our results demonstrate that, in this instance, depth provided a refuge for individuals from a high proportion of species in this Acropora-dominated assemblage. The persistence of deeper populations may provide a critical source of propagules to assist recovery of adjacent shallow-water reefs.
Bleaching of the Great Barrier Reef
The Australian Great Barrier Reef (GBR) is one of Earth's most extraordinary natural wonders, but it is vulnerable to climate change. Ainsworth et al. have tracked the effects of three decades of increasing heat stress on coral organisms. In the past, pulses of elevated temperatures that presaged hot seasons stimulated the acclimation of coral organisms and resilience to thermal stress. More recently, temperature hikes have been severe and precluded acclimation. The result has been increasing bleaching and death; notably extreme during 2016 in the wake of El Niño.
Science , this issue p. 338
Multinational conservation initiatives that prioritize investment across a region invariably navigate trade-offs among multiple objectives. It seems logical to focus where several objectives can be achieved efficiently, but such multi-objective hotspots may be ecologically inappropriate, or politically inequitable. Here we devise a framework to facilitate a regionally cohesive set of marine-protected areas driven by national preferences and supported by quantitative conservation prioritization analyses, and illustrate it using the Coral Triangle Initiative. We identify areas important for achieving six objectives to address ecosystem representation, threatened fauna, connectivity and climate change. We expose trade-offs between areas that contribute substantially to several objectives and those meeting one or two objectives extremely well. Hence there are two strategies to guide countries choosing to implement regional goals nationally: multi-objective hotspots and complementary sets of single-objective priorities. This novel framework is applicable to any multilateral or global initiative seeking to apply quantitative information in decision making.
http://dx.doi.org/10.1038/ncomms9208
Multinational conservation initiatives that prioritize investment across a region invariably navigate trade-offs among multiple objectives. It seems logical to focus where several objectives can be achieved efficiently, but such multi-objective hotspots may be ecologically inappropriate, or politically inequitable. Here we devise a framework to facilitate a regionally cohesive set of marine-protected areas driven by national preferences and supported by quantitative conservation prioritization analyses, and illustrate it using the Coral Triangle Initiative. We identify areas important for achieving six objectives to address ecosystem representation, threatened fauna, connectivity and climate change. We expose trade-offs between areas that contribute substantially to several objectives and those meeting one or two objectives extremely well. Hence there are two strategies to guide countries choosing to implement regional goals nationally: multi-objective hotspots and complementary sets of single-objective priorities. This novel framework is applicable to any multilateral or global initiative seeking to apply quantitative information in decision making.
As global warming continues, reef-building corals could avoid local population declines through “genetic rescue” involving
exchange of heat-tolerant genotypes across latitudes, but only if latitudinal variation in thermal tolerance is heritable.
Here, we show an up–to–10-fold increase in odds of survival of coral larvae under heat stress when their parents come from
a warmer lower-latitude location. Elevated thermal tolerance was associated with heritable differences in expression of oxidative,
extracellular, transport, and mitochondrial functions that indicated a lack of prior stress. Moreover, two genomic regions
strongly responded to selection for thermal tolerance in interlatitudinal crosses. These results demonstrate that variation
in coral thermal tolerance across latitudes has a strong genetic basis and could serve as raw material for natural selection.
Biological systems have similarities to efficient financial portfolios; the emergent properties of aggregate systems are often less volatile than their components. These portfolio effects derive from statistical averaging across the dynamics of system components, which often correlate weakly or negatively with each other through time and space. The "portfolio" concept when applied to ecological research provides important insights into how ecosystems are organized, how species interact, and how evolutionary strategies develop. It also helps identify appropriate scales for developing robust management and conservation schemes, and offers an approach that does not rely on prescriptive predictions about threats in an uncertain future. Rather, it presents a framework for managing risk from inevitable perturbations, many of which we will not be able to understand or anticipate.
An analysis of present-day global depth distributions of reef-building corals and underlying environmental drivers contradicts a commonly held belief that ocean warming will promote tropical coral expansion into temperate latitudes. Using a global data set of a major group of reef corals, we found that corals were confined to shallower depths at higher latitudes (up to 0.6 meters of predicted shallowing per additional degree of latitude). Latitudinal attenuation of the most important driver of this phenomenon-the dose of photosynthetically available radiation over winter-would severely constrain latitudinal coral range extension in response to ocean warming. Latitudinal gradients in species richness for the group also suggest that higher winter irradiance at depth in low latitudes allowed a deep-water fauna that was not viable at higher latitudes.
Copyright © 2015, American Association for the Advancement of Science.
Climate change is likely to lead to increasing population variability and extinction risk. Theoretically, greater population diversity should buffer against rising climate variability, and this theory is often invoked as a reason for greater conservation. However, this has rarely been quantified. Here we show how a portfolio approach to managing population diversity can inform metapopulation conservation priorities in a changing world. We develop a salmon metapopulation model in which productivity is driven by spatially distributed thermal tolerance and patterns of short- and long-term climate change. We then implement spatial conservation scenarios that control population carrying capacities and evaluate the metapopulation portfolios as a financial manager might: along axes of conservation risk and return. We show that preserving a diversity of thermal tolerances minimizes risk, given environmental stochasticity, and ensures persistence, given long-term environmental change. When the thermal tolerances of populations are unknown, doubling the number of populations conserved may nearly halve expected metapopulation variability. However, this reduction in variability can come at the expense of long-term persistence if climate change increasingly restricts available habitat, forcing ecological managers to balance society's desire for short-term stability and long-term viability. Our findings suggest the importance of conserving the processes that promote thermal-tolerance diversity, such as genetic diversity, habitat heterogeneity, and natural disturbance regimes, and demonstrate that diverse natural portfolios may be critical for metapopulation conservation in the face of increasing climate variability and change.
A great deal of research to inform environmental conservation and management takes a predict-and-prescribe strategy in which improving forecasts about future states of ecosystems is the primary goal. But sufficiently thorough understanding of ecosystems needed to reduce deep uncertainties is probably not achievable, seriously limiting the potential effectiveness of the predict-and-prescribe approach. Instead, research should integrate more closely with policy development to identify the range of alternative plausible futures and develop strategies that are robust across these scenarios and responsive to unpredictable ecosystem dynamics.
The genetic enhancement of wild animals and plants for characteristics that benefit human populations has been practiced for thousands of years, resulting in impressive improvements in commercially valuable species. Despite these benefits, genetic manipulations are rarely considered for noncommercial purposes, such as conservation and restoration initiatives. Over the last century, humans have driven global climate change through industrialization and the release of increasing amounts of CO2, resulting in shifts in ocean temperature, ocean chemistry, and sea level, as well as increasing frequency of storms, all of which can profoundly impact marine ecosystems. Coral reefs are highly diverse ecosystems that have suffered massive declines in health and abundance as a result of these and other direct anthropogenic disturbances. There is great concern that the high rates, magnitudes, and complexity of environmental change are overwhelming the intrinsic capacity of corals to adapt and survive. Although it is important to address the root causes of changing climate, it is also prudent to explore the potential to augment the capacity of reef organisms to tolerate stress and to facilitate recovery after disturbances. Here, we review the risks and benefits of the improvement of natural and commercial stocks in noncoral reef systems and advocate a series of experiments to determine the feasibility of developing coral stocks with enhanced stress tolerance through the acceleration of naturally occurring processes, an approach known as (human)-assisted evolution, while at the same time initiating a public dialogue on the risks and benefits of this approach.
Genetic rescue can increase the fitness of small, imperiled populations via immigration. A suite of studies from the past decade highlights the value of genetic rescue in increasing population fitness. Nonetheless, genetic rescue has not been widely applied to conserve many of the threatened populations that it could benefit. In this review, we highlight recent studies of genetic rescue and place it in the larger context of theoretical and empirical developments in evolutionary and conservation biology. We also propose directions to help shape future research on genetic rescue. Genetic rescue is a tool that can stem biodiversity loss more than has been appreciated, provides population resilience, and will become increasingly useful if integrated with molecular advances in population genomics.
Copyright © 2014 Elsevier Ltd. All rights reserved.
Climate change will alter many aspects of the ecology of organisms, including dispersal patterns and population connectivity. Understanding these changes is essential to predict future species distributions, estimate potential for adaptation, and design effective networks of protected areas. In marine environments, dispersal is often accomplished by larvae. At higher temperatures, larvae develop faster, but suffer higher mortality, making the effect of temperature on dispersal difficult to predict. Here, we experimentally calibrate the effect of temperature on larval survival and settlement in a dynamic model of coral dispersal. Our findings imply that most reefs globally will experience several-fold increases in local retention of larvae due to ocean warming. This increase will be particularly pronounced for reefs with mean water residence times comparable to the time required for species to become competent to settle. Higher local retention rates strengthen the link between abundance and recruitment at the reef scale, suggesting that populations will be more responsive to local conservation actions. Higher rates of local retention and mortality will weaken connectivity between populations, and thus potentially retard recovery following severe disturbances that substantially deplete local populations. Conversely, on isolated reefs that are dependent on replenishment from local broodstock, increases in local retention may hasten recovery.
Reef corals are highly sensitive to heat, yet populations resistant to climate change have recently been identified. To determine
the mechanisms of temperature tolerance, we reciprocally transplanted corals between reef sites experiencing distinct temperature
regimes and tested subsequent physiological and gene expression profiles. Local acclimatization and fixed effects, such as
adaptation, contributed about equally to heat tolerance and are reflected in patterns of gene expression. In less than 2 years,
acclimatization achieves the same heat tolerance that we would expect from strong natural selection over many generations
for these long-lived organisms. Our results show both short-term acclimatory and longer-term adaptive acquisition of climate
resistance. Adding these adaptive abilities to ecosystem models is likely to slow predictions of demise for coral reef ecosystems.
Coral bleaching caused by rising sea temperature is a primary cause of coral reef degradation. However, bleaching patterns often show significant spatial variability, therefore identifying locations where local conditions may provide thermal refuges is a high conservation priority. Coral bleaching mortality often diminishes with increasing depth, but clear depth zonation of coral communities and putative limited overlap in species composition between deep and shallow reef habitats has led to the conclusion that deeper reef habitats will provide limited refuge from bleaching for most species. Here, we show that coral mortality following a severe bleaching event diminished sharply with depth.
Bleaching-induced mortality of
Acropora was approximately 90% at 0-2m, 60% at 3-4 m, yet at 6-8m there was negligible mortality. Importantly, at least two-thirds of the shallow-water (2-3 m)
Acropora assemblage had a depth range that straddled the transition from high to low mortality. Cold-water upwelling may have contributed to the lower mortality observed in all but the shallowest depths. Our results demonstrate that, in this instance, depth provided a refuge for individuals from a high proportion of species in this
Acropora-dominated assemblage. The persistence of deeper populations may provide a critical source of propagules to assist recovery of adjacent shallow-water reefs.
Increased concern over climate change is demonstrated by the many efforts to assess climate effects and develop adaptation strategies. Scientists, resource managers, and decision makers are increasingly expected to use climate information, but they struggle with its uncertainty. With the current proliferation of climate simulations and downscaling methods, scientifically credible strategies for selecting a subset for analysis and decision making are needed. Drawing on a rich literature in climate science and impact assessment and on experience working with natural resource scientists and decision makers, we devised guidelines for choosing climate‐change scenarios for ecological impact assessment that recognize irreducible uncertainty in climate projections and address common misconceptions about this uncertainty. This approach involves identifying primary local climate drivers by climate sensitivity of the biological system of interest; determining appropriate sources of information for future changes in those drivers; considering how well processes controlling local climate are spatially resolved; and selecting scenarios based on considering observed emission trends, relative importance of natural climate variability, and risk tolerance and time horizon of the associated decision. The most appropriate scenarios for a particular analysis will not necessarily be the most appropriate for another due to differences in local climate drivers, biophysical linkages to climate, decision characteristics, and how well a model simulates the climate parameters and processes of interest. Given these complexities, we recommend interaction among climate scientists, natural and physical scientists, and decision makers throughout the process of choosing and using climate‐change scenarios for ecological impact assessment.
Selección y Uso de Escenarios de Cambio Climático para Estudios de Impacto Ecológico y Decisiones de Conservación
An increasing number of short-term experimental studies show significant effects of projected ocean warming and ocean acidification on the performance on marine organisms. Yet, it remains unclear if we can reliably predict the impact of climate change on marine populations and ecosystems, because we lack sufficient understanding of the capacity for marine organisms to adapt to rapid climate change. In this review, we emphasise why an evolutionary perspective is crucial to understanding climate change impacts in the sea and examine the approaches that may be useful for addressing this challenge. We first consider what the geological record and present-day analogues of future climate conditions can tell us about the potential for adaptation to climate change. We also examine evidence that phenotypic plasticity may assist marine species to persist in a rapidly changing climate. We then outline the various experimental approaches that can be used to estimate evolutionary potential, focusing on molecular tools, quantitative genetics, and experimental evolution, and we describe the benefits of combining different approaches to gain a deeper understanding of evolutionary potential. Our goal is to provide a platform for future research addressing the evolutionary potential for marine organisms to cope with climate change.
Projected effects of climate change on animal distributions primarily focus on consequences of temperature and largely ignore impacts of altered precipitation. While much evidence supports temperature‐driven range shifts, there is substantial heterogeneity in species' responses that remains poorly understood. We resampled breeding ranges of birds across three elevational transects in the Sierra Nevada Mountains, USA, that were extensively surveyed in the early 20th century. Presence–absence comparisons were made at 77 sites and occupancy models were used to separate significant range shifts from artifacts of false absences. Over the past century, rising temperature pushed species upslope while increased precipitation pulled them downslope, resulting in range shifts that were heterogeneous within species and among regions. While 84% of species shifted their elevational distribution, only 51% of upper or lower range boundary shifts were upslope. By comparison, 82% of range shifts were in a direction predicted by changes in either temperature or precipitation. Species were significantly more likely to shift elevational ranges than their ecological counterparts if they had small clutch sizes, defended all‐purpose territories, and were year‐round residents, results that were in opposition to a priori predictions from dispersal‐related hypotheses. Our results illustrate the complex interplay between species‐specific and region‐specific factors that structure patterns of breeding range change over long time periods. Future projections of increasing temperature and highly variable precipitation regimes create a strong potential for heterogeneous responses by species at range margins.
Climate change poses a challenge to the conventional approach to biodiversity conservation, which relies on fixed protected areas, because the changing climate is expected to shift the distribution of suitable areas for many species. Some species will persist only if they can colonize new areas, although in some cases their dispersal abilities may be very limited. To address this problem we devised a quantitative method for identifying multiple corridors of connectivity through shifting habitat suitabilities that seeks to minimize dispersal demands first and then the area of land required. We applied the method to Proteaceae mapped on a 1-minute grid for the western part of the Cape Floristic Region of South Africa, to supplement the existing protected areas, using Worldmap software. Our goal was to represent each species in at least 35 grid cells (approximately 100 km2 )a tall times between 2000 and 2050 despite climate change. Although it was possible to achieve the goal at reasonable cost, caution will be needed in applying our method to reserves or other conservation investments until there is further information to support or refine the climate-change models and the species' habitat-suitability and dispersal models.
Rising temperatures caused by climatic warming may cause poleward range shifts and/or expansions in species distribution. Tropical reef corals (hereafter corals) are some of the world's most important species, being not only primary producers, but also habitat-forming species, and thus fundamental ecosystem modification is expected according to changes in their distribution. Although most studies of climate change effects on corals have focused on temperature-induced coral bleaching in tropical areas, poleward range shifts and/or expansions may also occur in temperate areas. We show the first large-scale evidence of the poleward range expansion of modern corals, based on 80 years of national records from the temperate areas of Japan, where century-long measurements of in situ sea-surface temperatures have shown statistically significant rises. Four major coral species categories, including two key species for reef formation in tropical areas, showed poleward range expansions since the 1930s, whereas no species demonstrated southward range shrinkage or local extinction. The speed of these expansions reached up to 14 km/year, which is far greater than that for other species. Our results, in combination with recent findings suggesting range expansions of tropical coral-reef associated organisms, strongly suggest that rapid, fundamental modifications of temperate coastal ecosystems could be in progress.
No-analog communities (communities that are compositionally unlike any found today) occurred frequently in the past and will develop in the greenhouse world of the future. The well documented no-analog plant communities of late-glacial North America are closely linked to "novel" climates also lacking modern analogs, characterized by high seasonality of temperature. In climate simulations for the Intergovernmental Panel on Climate Change A2 and B1 emission scenarios, novel climates arise by 2100 AD, primarily in tropical and subtropical regions. These future novel climates are wanner than any present climates globally, with spatially variable shifts in precipitation, and increase the risk of species reshuffling into future no-analog communities and other ecological surprises. Most ecological models are at least partially parameterized from modern observations and so may fail to accurately predict ecological responses to these novel climates. There is an urgent need to test the robustness of ecological models to climate conditions outside modern experience.
Recent advances in DNA-sequencing technologies now allow for in-depth characterization of the genomic stress responses of many organisms beyond model taxa. They are especially appropriate for organisms such as reef-building corals, for which dramatic declines in abundance are expected to worsen as anthropogenic climate change intensifies. Different corals differ substantially in physiological resilience to environmental stress, but the molecular mechanisms behind enhanced coral resilience remain unclear. Here, we compare transcriptome-wide gene expression (via RNA-Seq using Illumina sequencing) among conspecific thermally sensitive and thermally resilient corals to identify the molecular pathways contributing to coral resilience. Under simulated bleaching stress, sensitive and resilient corals change expression of hundreds of genes, but the resilient corals had higher expression under control conditions across 60 of these genes. These "frontloaded" transcripts were less up-regulated in resilient corals during heat stress and included thermal tolerance genes such as heat shock proteins and antioxidant enzymes, as well as a broad array of genes involved in apoptosis regulation, tumor suppression, innate immune response, and cell adhesion. We propose that constitutive frontloading enables an individual to maintain physiological resilience during frequently encountered environmental stress, an idea that has strong parallels in model systems such as yeast. Our study provides broad insight into the fundamental cellular processes responsible for enhanced stress tolerances that may enable some organisms to better persist into the future in an era of global climate change.