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In this study, the authors describe a process that consistently identified sex based on differences in the length and characteristics of the urogenital papilla septum of Etelis carbunculus, a deep-water snapper (Lutjanidae, Etelinae). These characteristics, regardless of fish size, were found to be accurate for 96% of 157 specimens evaluated. The application of this external sex determination technique expedites the collection of sex-specific data and may perform well for other morphologically similar lutjanid snappers. The non-invasive method also minimizes damage to the fish, thereby allowing either its return to the ocean or landing as a valuable whole fish.

Measurements of life-history traits can reflect an organism’s response to environment. In wave-dominated rocky intertidal ecosystems, obtaining in-situ measurements of key grazing invertebrates are constrained by extreme conditions. Recent research demonstrates mollusc shells to be high-resolution sea-surface temperature proxies, as well as archival growth records. However, no prior molluscan climate proxy or life-history reconstruction has been demonstrated for the tropical rocky intertidal environment—a zone influenced by warmer waters, mixed tides, trade-wind patterns, and wave-action. Here, we show near-daily, spatiotemporal oxygen isotope signatures from the tropical rocky intertidal environment by coupling secondary ion mass spectrometry analysis of oxygen isotopes with the sclerochronology of an endemic Hawaiian intertidal limpet Cellana sandwicensis, that is a significant biocultural resource harvested for consumption. We also develop a method for reliable interpretation of seasonal growth patterns and longevity in limpets. This study provides a robust approach to explore tropical intertidal climatology and molluscan life-history. High-resolution rocky intertidal environment and life-history of tropical limpets, as determined by secondary ion mass spectrometry stable oxygen isotopic analysis of modern and historical mollusc shells.

Herbivorous fishes and urchins can contribute to reef resilience by removing algae that are competitive with corals, yet herbivorous fishes are frequently targeted by fishers. The deleterious effects of fishing on coral reef herbivore populations are thought to be decreased through the establishment of no-take marine protected areas (MPAs). We conducted surveys to compare the biomass, diversity, and size structure of herbivorous reef fish within three functional guilds (i.e., grazers, scrapers, and browsers) and herbivorous urchin populations inside and outside of four of O‘ahu’s current MPAs to determine if they were effectively protecting herbivorous fishes and assess any resulting effects on sea urchin competitors. We also characterized the benthos, including the identification of common taxa in algal turfs, to evaluate interactions between herbivory and benthic communities. Urchins and grazing fishes accounted for the majority of herbivore biomass across regions of O‘ahu, and the dominance of urchins suggests that they significantly contribute to herbivory. Coral cover was a significant predictor of urchin biomass, but urchins did not have a significant relationship with herbivorous fish biomass or MPA protection. MPA protection and depth had positive effects on herbivorous fish biomass when examined in aggregate. However, these results were largely influenced by a large MPA protection effect in the Hanauma Bay MPA, compared to weaker MPA effects in Kāne‘ohe Bay, Waikīkī, and Pūpūkea. Hanauma Bay had stark differences in the condition of reef habitats between the MPA and fished areas which may also confound the interpretation of a strongly significant protection effect. Depth and habitat complexity were significant predictors of both grazer biomass and aggregate herbivore community composition, suggesting that these bottom-up factors may have a greater impact on herbivorous fish biomass than protection. Turf communities were speciose and displayed similar trends to herbivore communities across regions, but within-region trends in the Hanauma Bay region suggest that turf species composition is not only dictated by top-down factors. Within-guild fish diversity was low across site and region, suggesting herbivory was dominated by a single or few species. The small size structure and densities of herbivorous fishes in MPAs across all regions limits their population-level functional and reproductive contributions. While MPAs serve as a popular fisheries management tool for coral reef environments, the limited benefits of MPAs for herbivorous fish and urchin populations around O‘ahu suggest a general need for improved fisheries management and enforcement, especially prior to the consideration of an expansion of the existing MPA network.

It is relatively well accepted that climate change can affect human pathogenic diseases; however, the full extent of this risk remains poorly quantified. Here we carried out a systematic search for empirical examples about the impacts of ten climatic hazards sensitive to greenhouse gas (GHG) emissions on each known human pathogenic disease. We found that 58% (that is, 218 out of 375) of infectious diseases confronted by humanity worldwide have been at some point aggravated by climatic hazards; 16% were at times diminished. Empirical cases revealed 1,006 unique pathways in which climatic hazards, via different transmission types, led to pathogenic diseases. The human pathogenic diseases and transmission pathways aggravated by climatic hazards are too numerous for comprehensive societal adaptations, highlighting the urgent need to work at the source of the problem: reducing GHG emissions.

Anthropogenic disturbances are posing unprecedented challenges to the persistence of ecosystems worldwide. The speed at which these disturbances reach an ecosystem’s tolerance thresholds will determine the time available for adaptation and conservation. Here, we aim to calculate the year after which a given environmental stressor permanently exceeds the bounds of an ecosystem’s tolerance. Ecosystem thresholds are here defined as limits in a given stressor beyond which ecosystems have showed considerable changes in community assembly and functioning, becoming remnants of what they once were, but not necessarily leading to species extirpation or extinction. Using the world’s coral reefs as a case example, we show that the projected effects of marine heatwaves, ocean acidification, storms, land-based pollution, and local human stressors are being underestimated considerably by looking at disturbances independently. Given the spatial complementarity in which numerous disturbances impact the world’s coral reefs, we show that the timelines of environmental suitability are halved when all disturbances are analyzed simultaneously, as opposed to independently. Under business-as-usual scenarios, the median year after which environmental conditions become unsuitable for the world’s remaining coral reefs was, at worse, 2050 for any one disturbance alone (28 years left); but when analyzed concurrently, this date was shortened to 2035 (13 years left). When analyzed together, disturbances reduced the date of environmental suitability because areas that may remain suitable under one disturbance could become unsuitable by any of several other variables. The significance of co-occurring disturbances at reducing timeframes of environmental suitability was evident even under optimistic scenarios. The best-case scenario, characterized by strong mitigation of greenhouse gas emissions and optimistic human development, resulted in 41% of global coral reefs with unsuitable conditions by 2100 under any one disturbance independently; yet when analyzed in combination up to 64% of the world’s coral reefs could face unsuitable environmental conditions by one disturbance or another. Under the worst-case scenario, nearly all coral reef ecosystems worldwide (approximately 99%) will permanently face unsuitable conditions by 2055 in at least one of the disturbances analyzed. Prior studies have indicated the projected dire effects of climate change on coral reefs by mid-century; by analyzing a multitude of projected disturbances, our study reveals a much more severe prognosis for the world’s coral reefs as they have significantly less time to adapt while highlighting the urgent need to tackle available solutions to human disturbances.

No-take marine reserves are common strategies used in spatial fisheries management. There are at least four general objectives for marine reserve design: (1) maximizing conservation, (2) minimizing total reserve area, (3) maximizing reserve compactness, and (4) minimizing socioeconomic opportunity cost (e.g., fisheries revenue). A spatial optimization model was developed to solve for reserve placements under those four objectives, while evaluating the bioeconomic tradeoffs and potential gaps of a subset of bottomfish restricted fishing areas (BRFAs) for the Hawaiian bottomfish fishery. Optimized reserve placements with minimal opportunity costs had little overlap (

The ongoing emission of greenhouse gases (GHGs) is triggering changes in many climate hazards that can impact humanity. We found traceable evidence for 467 pathways by which human health, water, food, economy, infrastructure and security have been recently impacted by climate hazards such as warming, heatwaves, precipitation, drought, floods, fires, storms, sea-level rise and changes in natural land cover and ocean chemistry. By 2100, the world’s population will be exposed concurrently to the equivalent of the largest magnitude in one of these hazards if emmisions are aggressively reduced, or three if they are not, with some tropical coastal areas facing up to six simultaneous hazards. These findings highlight the fact that GHG emissions pose a broad threat to humanity by intensifying multiple hazards to which humanity is vulnerable.

Most of the diversity on coral reefs is in the cryptofauna, the hidden organisms that inhabit the interstitial spaces of corals and other habitat-forming benthos. However, little is known about the patterns and drivers of diversity in cryptofauna. We investigated how the cryptofaunal community associated with the branching coral Pocillopora meandrina varies across spatial scales and environmental gradients. We performed nondestructive visual surveys of the cryptofaunal community on 751 P. meandrina colonies around the island of O‘ahu (30–73 colonies per site, 3–6 sites per region, five regions). We identified 91 species, including 48 fishes and 43 invertebrates. Most of these species were observed rarely, with only 19 species occurring on greater than 5% of surveyed colonies. Variation in community abundance and species richness was greatest at the scale of the coral colony and lowest at the site scale. Abundance and species richness increased with increasing colony size and maximum wave height, and decreased with increasing surface chlorophyll-a. In an analysis of species-specific responses, colony size, wave height, and chlorophyll-a were significant drivers of occurrence. Depth and percent live coral tissue were also identified as important correlates for community composition with distinct responses across taxa. Analyzing species-specific responses to environmental gradients documented a unique pattern for the guard crab Trapezia intermedia, which had a higher probability of occurring on smaller colonies (in contrast to 18 other common taxa). The results of a principal coordinates analysis on community composition and a co-occurrence analysis further supported T. intermedia as having a unique distribution across colonies, even in comparison with four other Trapezia species. Overall, these patterns emphasize the importance of host coral characteristics (i.e., colony size and percent live tissue) and physical characteristics of the surrounding habitat (i.e., wave energy, chlorophyll-a, and depth) in structuring cryptofaunal communities and characterize species-specific responses to environmental gradients.

Small unmanned aerial systems (sUAS) are an affordable, effective complement to existing coral reef monitoring and assessment tools. sUAS provide repeatable low-altitude, high-resolution photogrammetry to address fundamental questions of spatial ecology and community dynamics for shallow coral reef ecosystems. Here, we qualitatively describe the use of sUAS to survey the spatial characteristics of coral cover and the distribution of coral bleaching across patch reefs in Kāneʻohe Bay, Hawaii, and address limitations and anticipated technology advancements within the field of UAS. Overlapping sub-decimeter low-altitude aerial reef imagery collected during the 2015 coral bleaching event was used to construct high-resolution reef image mosaics of coral bleaching responses on four Kāneʻohe Bay patch reefs, totaling ~ 60,000 m2. Using sUAS imagery, we determined that paled, bleached and healthy corals on all four reefs were spatially clustered. Comparative analyses of data from sUAS imagery and in situ diver surveys found as much as 14% difference in coral cover values between survey methods, depending on the size of the reef and area surveyed. When comparing the abundance of unhealthy coral (paled and bleached) between sUAS and in situ diver surveys, we found differences in cover from 1 to 49%, depending on the depth of in situ surveys, the percent of reef area covered with sUAS surveys and patchiness of the bleaching response. This study demonstrates the effective use of sUAS surveys for assessing the spatial dynamics of coral bleaching at colony-scale resolutions across entire patch reefs and evaluates the complementarity of data from both sUAS and in situ diver surveys to more accurately characterize the spatial ecology of coral communities on reef flats and slopes.

We demonstrated a possible future wherein coral reefs shift to an algae-dominated state that retains low coral cover and a functional biomass of herbivorous fishes that sustains a reef fish fishery. We evaluate the effect of no-take marine protected areas (MPAs) and increased coastal nutrients under two Intergovernmental Panel on Climate Change climate scenarios for years 2000–2100, which are implemented as coral bleaching events. Coral mortality from bleaching events drove a lagged increase in herbivorous fish populations via a shift from coral-dominated to algae-dominated habitats. Biomass and catch of piscivorous fish declined significantly, with the fishery shifting to the harvest of herbivorous fish. No-take MPAs for 20% of reef areas represented a threshold that had a positive effect on herbivorous fishes but no influence on the steep declines of corals and piscivorous fishes. Contemporary no-take MPAs protect less than 1% of coral reef areas around the Hawaiian Islands; substantial management action would be required to approach the 20% area threshold.

Project funding was provided by the Colonel Willys E. Lord, DVM and Sandina L. Lord Endowed Scholarship (to ZSO), the Carol Ann and Myron K. Hayashida Scholarship (to ZSO), and the NMFS-Sea Grant Population Dynamics Fellowship (to ZSO). The BotCam data were collected, processed, organized, and provided by: V. Moriwake, C. Demarke, B. Alexander, C. Kelley, W. Misa, J. Friedman, D. Tokishi, B. Richards, D. Kobayashi, and A. Rollo. Funding for the BotCam work was provided by the State of Hawaii Division of Aquatic Resources and the Federal Aid in Sport Fish Restoration program (F17R35-study IX), NOAA Pacific Islands Regional Office, Kahoolawe Island Reserve Commission, NOAA Pacific Island Fisheries Science Center, the Joint Institute for Marine and Atmospheric Research at the University of Hawaii at Manoa, the NOAA Fisheries Office of Science and Technology, and the NOAA Fisheries Advanced Science at Technology Working Group. All funding sources had no involvement in the study design, collection, analysis, and interpretation of the data nor in the writing of this manuscript. This manuscript is SOEST contribution #10019 and HIMB contribution #1686.

The chevron butterflyfish Chaetodon trifascialis is an obligate corallivore found on Indo-Pacific coral reefs. The typical northern extent of the distributional range of the chevron butterflyfish overlaps with the occurrence of one of its preferred corals Acropora cytherea on reefs of French Frigate Shoals in the Northwestern Hawaiian Islands. Here I document the occurrence of a single C. trifascialis in Kaneohe Bay, Oahu outside its typical range and discuss the role of biogeographic vagrants as potential colonizers that provide direct evidence of inter-island larval connectivity in the Central Pacific Ocean.

Mesophotic coral ecosystems (MCEs) represent the lowest depth distribution inhabited by many coral reef-associated organisms. Research on fishes associated with MCEs is sparse, leading to a critical lack of knowledge of how reef fish found at mesophotic depths may vary from their shallow reef conspecifics. We investigated intraspecific variability in body condition and growth of three Hawaiian endemics collected from shallow, photic reefs (5–33 m deep) and MCEs (40–75 m) throughout the Hawaiian Archipelago and Johnston Atoll: the detritivorous goldring surgeonfish, Ctenochaetus strigosus, and the planktivorous threespot chromis, Chromis verater, and Hawaiian dascyllus, Dascyllus albisella. Estimates of body condition and size-at-age varied between shallow and mesophotic depths; however, these demographic differences were outweighed by the magnitude of variability found across the latitudinal gradient of locations sampled within the Central Pacific. Body condition and maximum body size were lowest in samples collected from shallow and mesophotic Johnston Atoll sites, with no difference occurring between depths. Samples from the Northwestern Hawaiian Islands tended to have the highest body condition and reached the largest body sizes, with differences between shallow and mesophotic sites highly variable among species. The findings of this study support newly emerging research demonstrating intraspecific variability in the life history of coral-reef fish species whose distributions span shallow and mesophotic reefs. This suggests not only that the conservation and fisheries management should take into consideration differences in the life histories of reef-fish populations across spatial scales, but also that information derived from studies of shallow fishes be applied with caution to conspecific populations in mesophotic coral environments.

Bitcoin is a power-hungry cryptocurrency that is increasingly used as an investment and payment system. Here we show that projected Bitcoin usage, should it follow the rate of adoption of other broadly adopted technologies, could alone produce enough CO2 emissions to push warming above 2 °C within less than three decades.

Este artículo contiene 10 páginas, 5 figuras., Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages—the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014–2017 global coral bleaching event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.

A diet analysis was conducted on 444 wahoo Acanthocybium solandri caught in the central North Pacific Ocean longline fishery and a nearshore troll fishery surrounding the Hawaiian Islands from June to December 2014. In addition to traditional observational methods of stomach contents, a DNA bar-coding approach was integrated into the analysis by sequencing the cytochrome c oxidase subunit 1 (COI) region of the mtDNA genome to taxonomically identify individual prey items that could not be classified visually to species. For nearshore-caught A. solandri, juvenile pre-settlement reef fish species from various families dominated the prey composition during the summer months, followed primarily by Carangidae in autumn months. Gempylidae, Echeneidae and Scombridae were dominant prey taxa from the offshore fishery. Molidae was a common prey family found in stomachs collected north-east of the Hawaiian Archipelago while tetraodontiform reef fishes, known to have extended pelagic stages, were prominent prey items south-west of the Hawaiian Islands. The diet composition of A. solandri was indicative of an adaptive feeder and thus revealed dominant geographic and seasonal abundances of certain taxa from various ecosystems in the marine environment. The addition of molecular bar-coding to the traditional visual method of prey identifications allowed for a more comprehensive range of the prey field of A. solandri to be identified and should be used as a standard component in future diet studies.

Pristipomoides filamentosus is an economically and culturally important species of deepwater snapper found throughout the tropical Indo-Pacific. From 1989–1993, the State of Hawaii initiated a tagging program with fish opportunistically recaptured by scientists and fishers to quantify growth and other life history parameters. Over approximately 10 years, 10.5 % of 4179 tagged P. filamentosus were recaptured. We used these data to compare von Bertalanffy growth parameters estimated using Bayesian and likelihood approaches. Next, we defined an objective cost function to estimate growth parameters that integrated the tagging data with direct aging and length frequency data used in previous regional growth studies. Our results reconcile 30+ years of effort from various methods to estimate growth parameters for P. filametosus in Hawaii ( L ∞ = 68.14 cm FL [95 % Confidence Interval (CI): 65.42–69.54] and K = 0.22 yr−1 [CI: 0.20–0.25]), demonstrate the importance of individual variability in the species due primarily to the asymptotic length parameter L ∞ , and suggest the effects of sexual dimorphism on growth as a focus of future inquiry. These results have direct management implications as growth is a critical input for age-based stock assessment models and often used as a proxy for other life history traits.

Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages-the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014-2017 global coral bleaching event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.

The structure and dynamics of coral reef environments vary across a range of spatial scales, with patterns of associated faunal assemblages often reflecting this variability. However, delineating drivers of biological variability in such complex environments has proved challenging. Here, we investigated the assemblage structure and diversity of parrotfishes&mdash, a common and ecologically important group&mdash, across 6&deg, of latitude on the Northern Great Barrier Reef (GBR), Australia. Parrotfish abundance and biomass were determined from stereo-video surveys across 82 sites spanning 31 reefs and assessed against geographic, biophysical, and management-related factors in a multivariate framework to determine major drivers and associated scales of assemblage structure. Large cross-shelf variation in parrotfish assemblages pervaded along the entire Northern GBR, with distinct assemblages associated with sheltered and exposed reefs. Species abundances and diversity generally decreased with decreasing latitude. The gradient of explicit predator biomass associated with management zoning had no effect on parrotfish assemblage structure, but was positively correlated with parrotfish diversity. Our results highlight the ubiquitous presence of cross-shelf variation, where the greatest differences in parrotfish community composition existed between sheltered (inner and mid shelf) and exposed (outer shelf) reef systems. Prior attempts to explain linkages between parrotfishes and fine-scale biophysical factors have demonstrated parrotfishes as habitat generalists, but recent developments in nutritional ecology suggest that their cross-shelf variation on the GBR is likely reflective of benthic resource distribution and species-specific feeding modes.

Fisheries surveys over broad spatial areas are crucial in defining and delineating appropriate fisheries management areas. Yet accurate mapping and tracking of fishing activities remain largely restricted to developed countries with sufficient resources to use automated identification systems and vessel monitoring systems. For many countries, the spatial extent and boundaries of fishing grounds are not completely known. We used satellite images at night to detect fishing grounds in the Philippines for fishing gears that use powerful lights to attract coastal pelagic fishes. We used nightly boat detection data, extracted by U.S. NOAA from the Visible Infrared Imaging Radiometer Suite (VIIRS), for the Philippines from 2012 to 2016, covering 1713 nights, to examine spatio-temporal patterns of fishing activities in the country. Using density-based clustering, we identified 134 core fishing areas (CFAs) ranging in size from 6 to 23,215 km2 within the Philippines’ contiguous maritime zone. The CFAs had different seasonal patterns and range of intensities in total light output, possibly reflecting differences in multi-gear and multi-species signatures of fishing activities in each fishing ground. Using maximum entropy modeling, we identified bathymetry and chlorophyll as the main environmental predictors of spatial occurrence of these CFAs when analyzed together, highlighting the multi-gear nature of the CFAs. Applications of the model to specific CFAs identified different environmental drivers of fishing distribution, coinciding with known oceanographic associations for a CFA’s dominant target species. This case study highlights nighttime satellite images as a useful source of spatial fishing effort information for fisheries, especially in Southeast Asia.

Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism's function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.

Analyzing tradeoffs among ecological, economic, and management goals with respect to marine reserve network design is an important facet of systematic conservation planning. We designed an integer linear programming model to quantify tradeoffs among five marine reserve network aspects: ecological conservation value, economic opportunity cost, geographic domain size, total reserve area, and reserve spatial compactness. Using ecological and economic data from the Hawaiian deepwater bottomfish fishery as a case study, an integer linear programming model was designed to choose areas that 1) maximize conservation value and 2) minimize opportunity cost, defined as foregone fisheries revenue. Compromise solutions that equally weighted conservation value and opportunity cost resulted in solutions with dramatically lower foregone fisheries revenue and a relatively small loss in conservation value compared to solutions with the maximum conservation value. When opportunity cost was assumed uniform across the spatial domain, solutions had considerably higher foregone revenue for a given level of conservation value, highlighting the drawback of not including a spatially explicit metric of opportunity cost in reserve selection models. Inclusion of only indicator species, rather than the entire species complex, in the optimization led to considerable representation gaps in conservation value for non-included species. We found that optimizations performed at the archipelago scale provided geographically disproportionate reserve allocations and thus disproportionate conservation benefits and socioeconomic impacts across geopolitically distinct island regions. We showed how reserve selection models can be used to support systematic conservation planning exercises characterized by many diverse and conflicting objectives and parties.

a b s t r a c t Commercial and recreational fisheries target hundreds of fish and shellfish species across the seascape of southern Florida including inshore coastal bays, the flats of barrier islands, coral reefs and offshore pelagic waters. The ecological dynamics and economic sustainability of these valuable fishery resources are key conservation concerns. This study examined two ecological indicators of fishing impacts on exploited populations: (1) the more traditional metric catch per unit of fishing effort (CPUE); and (2) the non-traditional metric average length (¯) in the exploited life stage of a population. We show that both indicators were closely related to stock productivity via fisheries population dynamics theory, and that either indicator could be used to estimate fishing mortality rates (F). Data requirements are much less stringent for estimating F from theindicator than CPUE, making it more practical for data-poor situations common to tropical marine fisheries. Using indicator-based estimates of ˆ F within a popula- tion dynamic modeling framework enabled an evaluation of fishing impacts on sustainability at both the species and community levels, an important step toward ecosystem-based fisheries assessment and management. A comparison of these approaches applied to the assessment of southern Florida coral reef fisheries suggested that fishing has fundamentally altered the ecological structure of the fish community by depleting the biomass of higher-trophic level carnivores to the extent that the stocks are unsustainable.

Aim To explore the spatial and temporal genetic structure of four tropical hermit crabs in the genus Calcinus with varying habitat use in order to test for impacts of sea-level change and demography in shaping contemporary population structure and to understand how this structure relates to the process of speciation in the genus. Location Central Pacific. Methods We sequenced 586 bp of the cytochrome c oxidase subunit I gene (COI) (n = 702) and analysed the data for population differentiation and demographic changes. We complemented the sequences with abundance surveys of targeted species and modelled potential habitat availability in response to sea-level change. Results Sequence data revealed high haplotype diversity (h = 0.685–0.983) and low nucleotide diversity (π = 0.002–0.018) for all species. There was little population differentiation and extensive geographical haplotype sharing within all species, despite dramatic shifts in the abundance of species among locations, which appear to result from ecological interactions rather than limits to contemporary larval dispersal. Population expansion occurred most recently in the subtidal species Calcinus haigae (30–70 ka), whereas the intertidal species showed earlier expansions: Calcinus seurati: 110–140 ka, and Calcinus laevimanus: 220–250 ka. Differences in timing can be linked to the prediction that subtidal habitat area is strongly affected by changing sea level, while intertidal habitat area is affected less strongly. Interestingly, unlike the West Pacific, habitat in the Central Pacific remains relatively equidistant. Main conclusions Habitat availability during sea-level fluctuations, rather than dispersal limitation per se, appears to be a potential force shaping the population genetic patterns of subtidal species, and perhaps speciation of tropical Calcinus hermit crabs. Insofar as this represents a general pattern, historical sea-level change may play a role in structuring Central Pacific reef species through alteration of habitat availability rather than isolation and vicariance.

Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism’s function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.

The risk of global extinction of reef-building coral species is increasing. We evaluated extinction risk using a biological trait-based resiliency index that was compared with Caribbean extinction during the Plio-Pleistocene, and with extinction risk determined by the International Union for Conservation of Nature (IUCN). Through the Plio-Pleistocene, the Caribbean supported more diverse coral assemblages than today and shared considerable overlap with contemporary Indo-Pacific reefs. A clear association was found between extant Plio-Pleistocene coral genera and our positive resilience scores. Regional extinction in the past and vulnerability in the present suggests that Pocillopora, Stylophora and foliose Pavona are among the most susceptible taxa to local and regional isolation. These same taxa were among the most abundant corals in the Caribbean Pliocene. Therefore, a widespread distribution did not equate with immunity to regional extinction. The strong relationship between past and present vulnerability suggests that regional extinction events are trait-based and not merely random episodes. We found several inconsistencies between our data and the IUCN scores, which suggest a need to critically re-examine what constitutes coral vulnerability.