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Abstract ObjectiveFisheries provide countless benefits to human populations but face many threats ranging from climate change to overfishing. Despite these threats and an increase in fishing pressure globally, most stocks remain unassessed and data limited. An abundance of data-limited assessment methods exists, but each has different data requirements, caveats, and limitations. Furthermore, developing informative model priors can be difficult when little is known about the stock, and uncertain model parameters could create misleading results about stock status. Our research illustrates an approach for rapidly creating robust initial assessments of unregulated and data-limited fisheries without the need for additional data collection. MethodsOur method uses stakeholder knowledge combined with a series of data-limited tools to identify an appropriate stock assessment method, conduct an assessment, and examine how model uncertainty influences the results. Our approach was applied to the unregulated and data-limited fishery for Crevalle Jack Caranx hippos in Florida. ResultResults suggested a steady increase in exploitation and a decline in stock biomass over time, with the stock currently overfished and undergoing overfishing. These findings highlight a need for management action to prevent continued stock depletion. ConclusionOur approach can help to streamline the initial assessment and management process for unregulated and data-limited stocks and serves as an additional tool for combating the many threats facing global fisheries.more » « less
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Abstract The restoration of urban estuaries is challenging due to the complexity of prioritizing sites in a context of social and biophysical unevenness. Site prioritization and selection are crucial components of ecological success and equity in restoration. In many cases, site prioritization is conducted according to simple opportunity or political expediency, but this needs to be investigated further in local contexts, with accompanying analysis of the impacts on urban environmental equity. Using a critical physical geography framework, I explore site selection processes in the restoration of Biscayne Bay through case studies of two urban streams. I use multiple data types to present an integrated perspective on urban restoration priority and the social context that produces restoration siting decisions. I find that the logics of restoration site selection in the Biscayne Bay watershed have produced ecologically questionable decisions and inequitable outcomes. Therefore, I argue that restoration decision making needs to include environmental justice criteria.more » « less
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Abstract The plastic ability for a range of phenotypes to be exhibited by the same genotype allows organisms to respond to environmental variation and may modulate fitness in novel environments. Differing capacities for phenotypic plasticity within a population, apparent as genotype by environment interactions (GxE), can therefore have both ecological and evolutionary implications. Epigenetic gene regulation alters gene function in response to environmental cues without changes to the underlying genetic sequence and likely mediates phenotypic variation. DNA methylation is currently the most well described epigenetic mechanism and is related to transcriptional homeostasis in invertebrates. However, evidence quantitatively linking variation in DNA methylation with that of phenotype is lacking in some taxa, including reef‐building corals. In this study, spatial and seasonal environmental variation in Bonaire, Caribbean Netherlands was utilized to assess relationships between physiology and DNA methylation profiles within genetic clones across different genotypes ofAcropora cervicornisandA. palmatacorals. The physiology of both species was highly influenced by environmental variation compared to the effect of genotype. GxE effects on phenotype were only apparent inA. cervicornis. DNA methylation in both species differed between genotypes and seasons and epigenetic variation was significantly related to coral physiological metrics. Furthermore, plastic shifts in physiology across seasons were significantly positively correlated with shifts in DNA methylation profiles in both species. These results highlight the dynamic influence of environmental conditions and genetic constraints on the physiology of two important Caribbean coral species. Additionally, this study provides quantitative support for the role of epigenetic DNA methylation in mediating phenotypic plasticity in invertebrates.more » « less
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Abstract Algal symbiont shuffling in favour of more thermotolerant species has been shown to enhance coral resistance to heat‐stress. Yet, the mechanistic underpinnings and long‐term implications of these changes are poorly understood. This work studied the modifications in coral DNA methylation, an epigenetic mechanism involved in coral acclimatization, in response to symbiont manipulation and subsequent heat stress exposure. Symbiont composition was manipulated in the great star coralMontastraea cavernosathrough controlled thermal bleaching and recovery, producing paired ramets of three genets dominated by either their native symbionts (genusCladocopium) or the thermotolerant species (Durusdinium trenchi). Single‐base genome‐wide analyses showed significant modifications in DNA methylation concentrated in intergenic regions, introns and transposable elements. Remarkably, DNA methylation changes in response to heat stress were dependent on the dominant symbiont, with twice as many differentially methylated regions found in heat‐stressed corals hosting different symbionts (Cladocopiumvs.D.trenchii) compared to all other comparisons. Interestingly, while differential gene body methylation was not correlated with gene expression, an enrichment in differentially methylated regions was evident in repetitive genome regions. Overall, these results suggest that changes in algal symbionts favouring heat tolerant associations are accompanied by changes in DNA methylation in the coral host. The implications of these results for coral adaptation, along with future avenues of research based on current knowledge gaps, are discussed in the present work.more » « less
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Most research on pharmaceutical presence in the environment to date has focused on smaller scale assessments of freshwater and riverine systems, relying mainly on assays of water samples, while studies in marine ecosystems and of exposed biota are sparse. This study investigated the pharmaceutical burden in bonefish (Albula vulpes), an important recreational and artisanal fishery, to quantify pharmaceutical exposure throughout the Caribbean Basin. We sampled 74 bonefish from five regions, and analyzed them for 102 pharmaceuticals. We assessed the influence of sampling region on the number of pharmaceuticals, pharmaceutical assemblage, and risk of pharmacological effects. To evaluate the risk of pharmacological effects at the scale of the individual, we proposed a metric based on the human therapeutic plasma concentration (HTPC), comparing measured concentrations to a threshold of 1/3 the HTPC for each pharmaceutical. Every bonefish had at least one pharmaceutical, with an average of 4.9 and a maximum of 16 pharmaceuticals in one individual. At least one pharmaceutical was detected in exceedance of the 1/3 HTPC threshold in 39% of bonefish, with an average of 0.6 and a maximum of 11 pharmaceuticals exceeding in a Key West individual. The number of pharmaceuticals (49 detected in total) differed across regions, but the risk of pharmacological effects did not (23 pharmaceuticals exceeded the 1/3 HTPC threshold). The most common pharmaceuticals were venlafaxine (43 bonefish), atenolol (36), naloxone (27), codeine (27), and trimethoprim (24). Findings suggest that pharmaceutical detections and concentration may be independent, emphasizing the need to monitor risk to biota regardless of exposure diversity, and to focus on risk quantified at the individual level. This study supports the widespread presence of pharmaceuticals in marine systems and shows the utility of applying the HTPC to assess the potential for pharmacological effects, and thus quantify impact of exposure at large spatial scales.more » « less
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Phenotypic plasticity is defined as a property of individual genotypes to produce different phenotypes when exposed to different environmental conditions. This ability may be expressed at behavioral, biochemical, physiological, and/or developmental levels, exerting direct influence over species' demographic performance. In reef-building corals, a group critically threatened by global change in the Anthropocene, non-genetic mechanisms (i.e., epigenetic and microbiome variation) have been shown to participate in plastic physiological responses to environmental change. Yet, the precise way in which these mechanisms interact, contribute to such responses, and their adaptive potential is still obscure. The present work aims to fill this gap by using a multi-omics approach to elucidate the contribution and interconnection of the mechanisms modulating phenotypic plasticity in staghorn coral (Acropora cervicornis) clones subject to different depth conditions. Results show changes in lipidome, epigenome and transcriptome, but not in symbiotic and microbial communities. In addition, a potential shift toward a more heterotrophic feeding behavior was evidenced in corals at the deeper site. These observations are consistent with a multi-mechanism modulation of rapid acclimation in corals, underscoring the complexity of this process and the importance of a multifactorial approach to inform potential intervention to enhance coral adaptive capacity.more » « less