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This research investigated the reproductive biology (sex ratio, hermaphroditic pattern, size and age at maturity) of Cephalopholis argus, known locally in Hawaii by its Tahitian name roi. The results suggest that C. argus exhibits monandric protogyny (female gonad differentiation with female to male sex change) with females reaching sexual maturity at 1.2 years (95% c.i.: 0.6, 1.6) and 20.0 cm total length (LT ; 95% c.i.: 19.6, 21.2). The female to male sex ratio was 3.9:1. The average age and LT at sex change was 11.5 years (95% c.i.: 11.1, 12.9) and 39.9 cm (95% c.i.: 39.5, 41.2), respectively. Current information on spawning seasonality of this species is incomplete, but based on the occurrence of spawning capable and actively spawning females, spawning probably takes place from May to October. Evidence of lunar spawning periodicity was found, with an increased proportion of spawning capable and actively spawning females, and an increased female gonado-somatic index during first quarter and full-moon phases. This information fills a valuable information gap in Hawaii and across the species' native range.

Coral reefs are among the most species-rich and threatened ecosystems on Earth, yet the extent to which human stressors determine species occurrences, compared with biogeography or environmental conditions, remains largely unknown. With ever-increasing human-mediated disturbances on these ecosystems, an important question is not only how many species can inhabit local communities, but also which biological traits determine species that can persist (or not) above particular disturbance thresholds. Here we show that human pressure and seasonal climate variability are disproportionately and negatively associated with the occurrence of large-bodied and geographically small-ranging fishes within local coral reef communities. These species are 67% less likely to occur where human impact and temperature seasonality exceed critical thresholds, such as in the marine biodiversity hotspot: the Coral Triangle. Our results identify the most sensitive species and critical thresholds of human and climatic stressors, providing opportunity for targeted conservation intervention to prevent local extinctions., Knowing which species traits may confer resilience to human-mediated stressors will help predict future impacts on biodiversity. Here, Mellin et al. show that large bodied fish with small geographic ranges are disproportionately affected by the negative impacts of human disturbance and climate variability.

Phytoplankton production drives marine ecosystem trophic-structure and global fisheries yields. Phytoplankton biomass is particularly influential near coral reef islands and atolls that span the oligotrophic tropical oceans. The paradoxical enhancement in phytoplankton near an island-reef ecosystem—Island Mass Effect (IME)—was first documented 60 years ago, yet much remains unknown about the prevalence and drivers of this ecologically important phenomenon. Here we provide the first basin-scale investigation of IME. We show that IME is a near-ubiquitous feature among a majority (91%) of coral reef ecosystems surveyed, creating near-island ‘hotspots' of phytoplankton biomass throughout the upper water column. Variations in IME strength are governed by geomorphic type (atoll vs island), bathymetric slope, reef area and local human impacts (for example, human-derived nutrient input). These ocean oases increase nearshore phytoplankton biomass by up to 86% over oceanic conditions, providing basal energetic resources to higher trophic levels that support subsistence-based human populations., The Island Mass Effect (IME), where island proximity enhances phytoplankton biomass, remains a poorly understood phenomenon. Here, the authors show the IME is a common feature among Pacific reefs, driving increased production that creates biological hotspots in otherwise barren ocean basins.

Pacific Island nations and territories must build their capacity to harvest pelagic fishes to ensure domestic food security into the future. The Republic of Palau recently created the Palau National Marine Sanctuary, a Marine Managed Area that was intended to conserve marine resources and enhance local pelagic fisheries. However, the capacity of the nation’s domestic fishery to exploit pelagic species must be built to meet these objectives and, to this aim, the development of a coastal network of Fish Attracting Devices (FADs) has been proposed. To inform the development of the nation’s FAD program, we used acoustic telemetry to study the movements of yellowfin tuna (Thunnus albacares) within Palau’s existing FAD network. Subadult yellowfin tuna (50−79 cm FL) remained within the FAD network for up to 175 days and young-of-the-year yellowfin tuna spent significantly more time in association with FADs in comparison to year-1 fish. A network analysis suggests that the Ngardmau and Peleliu FADs were the most important components of the current FAD network, and a mixed effects Poisson generalized linear model indicated that the residency of yellowfin tuna to these FADs was significantly related to mooring depth and distance from the reef. These results provide a description of yellowfin tuna movements within Palau’s FAD network and recommendations to improve the nation’s FAD program that are also applicable to other Pacific Island nations and territories that desire to improve domestic access to pelagic fish stocks.

Este artículo contiene 23 páginas, 6 figuras, 6 tablas., The kelp forests of southern South America are some of the least disturbed on the planet. The remoteness of this region has, until recently, spared it from many of the direct anthropogenic stressors that have negatively affected these ecosystems elsewhere. Re-surveys of 11 locations at the easternmost extent of Tierra del Fuego originally conducted in 1973 showed no significant differences in the densities of adult and juvenile Macrocystis pyrifera kelp or kelp holdfast diameter between the two survey periods. Additionally, sea urchin assemblage structure at the same sites were not significantly different between the two time periods, with the dominant species Loxechinus albus accounting for 66.3% of total sea urchin abundance in 2018 and 61.1% in 1973. Time series of Landsat imagery of the region from 1998 to 2018 showed no long-term trends in kelp canopy over the past 20 years. However, ~ 4-year oscillations in canopy fraction were observed and were strongly and negatively correlated with the NOAA Multivariate ENSO index and sea surface temperature. More extensive surveying in 2018 showed significant differences in benthic community structure between exposed and sheltered locations. Fish species endemic to the Magellanic Province accounted for 73% of all nearshore species observed and from 98–100% of the numerical abundance enumerated at sites. Fish assemblage structure varied significantly among locations and wave exposures. The recent creation of the Yaganes Marine Park is an important step in protecting this unique and biologically rich region; however, the nearshore waters of the region are currently not included in this protection. There is a general lack of information on changes in kelp forests over long time periods, making a global assessment difficult. A complete picture of how these ecosystems are responding to human pressures must also include remote locations and locations with little to no impact., We received fundingfrom The Brooks Foundation,The Keith CampbellFoundationfor the Environment, The Case Foundation,Leonardo DiCaprio Foundation,Davidoff, The Don Quixote Foundation,Roger and Rosemary Enrico Foundation,HelmsleyCharitable Trust, Lindblad Expeditions-National Geographic Fund,Philip Stephenson Foundation,Vicki and Roger Sant, The Waitt Foundation,and The National Geographic Society.

Through research, restoration of agro-ecological sites, and a renaissance of cultural awareness in Hawaiʻi, there has been a growing recognition of the ingenuity of the Hawaiian biocultural resource management system. The contemporary term for this system, &ldquo, the ahupuaʻa system&rdquo, does not accurately convey the nuances of system function, and it inhibits an understanding about the complexity of the system&rsquo, s management. We examined six aspects of the Hawaiian biocultural resource management system to understand its framework for systematic management. Based on a more holistic understanding of this system&rsquo, s structure and function, we introduce the term, &ldquo, the moku system&rdquo, to describe the Hawaiian biocultural resource management system, which divided large islands into social-ecological regions and further into interrelated social-ecological communities. This system had several social-ecological zones running horizontally across each region, which divided individual communities vertically while connecting them to adjacent communities horizontally, and, thus, created a mosaic that contained forested landscapes, cultural landscapes, and seascapes, which synergistically harnessed a diversity of ecosystem services to facilitate an abundance of biocultural resources. &ldquo, The moku system&rdquo, is a term that is more conducive to large-scale biocultural restoration in the contemporary period, while being inclusive of the smaller-scale divisions that allowed for a highly functional system.

The people of Oceania have long relied on the ocean for sustenance, commerce, and cultural identity, which promulgated a sophisticated understanding of the marine environment and its conservation. Global declines in ocean health now require innovative solutions that can benefit from customary knowledge and practices, which in the past led to sustainable marine resource use. The resurgence of local stewardship, which incorporates customary practices and governance, has shown promise in many locations throughout the Pacific, although a complete return to past practices is not fully implementable owing to the loss of traditional knowledge, centralized governmental structures, economic development, and globalization. Hybrid systems that incorporate elements of customary and contemporary management can overcome some of these limitations to implementation of successful local management, and lead to greater food security, social cohesion, and the creation of an adaptive system that can potentially mitigate the effects of climate change and other stressors.

Designated large-scale marine protected areas (LSMPAs, 100,000 or more square kilometers) constitute over two-thirds of the approximately 6.6% of the ocean and approximately 14.5% of the exclusive economic zones within marine protected areas. Although LSMPAs have received support among scientists and conservation bodies for wilderness protection, regional ecological connectivity, and improving resilience to climate change, there are also concerns. We identified 10 common criticisms of LSMPAs along three themes: (1) placement, governance, and management; (2) political expediency; and (3) social ecological value and cost. Through critical evaluation of scientific evidence, we discuss the value, achievements, challenges, and potential of LSMPAs in these arenas. We conclude that although some criticisms are valid and need addressing, none pertain exclusively to LSMPAs, and many involve challenges ubiquitous in management. We argue that LSMPAs are an important component of a diversified management portfolio that tempers potential losses, hedges against uncertainty, and enhances the probability of achieving sustainably managed oceans. Fil: O'Leary, Bethan C. University Of York; Reino Unido Fil: Ban, Natalie C. University of Victoria; Canadá Fil: Fernandez, Miriam. Pontificia Universidad Católica de Chile; Chile. Universidad Católica de Chile; Chile Fil: Friedlander, Alan M. University of Hawaii at Manoa; Estados Unidos Fil: Garcia Borboroglu, Jorge Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Golbuu, Yimnang. Palau International Coral Reef Center; Palaos Fil: Guidetti, Paolo. Universite Nice; Francia Fil: Harris, Jean M. Ezemvelo Kzn Wildlife; Sudáfrica Fil: Hawkins, Julie P. University Of York; Reino Unido Fil: Langlois, Tim. University of Western Australia; Australia Fil: McCauley, Douglas J. University of California; Estados Unidos Fil: Pikitch, Ellen K. Stony Brook University; Estados Unidos. University Of York; Reino Unido Fil: Richmond, Robert H. University Of York; Reino Unido Fil: Roberts, Callum M. University of Hawaii at Manoa; Estados Unidos

Coral reefs sustain millions of people worldwide, yet in recent years, social, environmental, and climate change have caused major declines in coral reef fisheries. Small-scale coral reef fisheries research has largely focused on community-level drivers of fishing, ignoring the heterogeneities that exist within communities. We used social-ecological indicators from 20 coastal villages in Fiji to identify potential fine-scale, context-appropriate drivers of estimated household fish catch. Indicators were developed based on a review of the literature, discussions with local experts, and a pilot study. Using structural equation models, we found that importance of fishing to income, household fish consumption, livelihood diversity, travel time to market, and coral reef area all positively affect estimated household-level fish catch. Our results contrast with findings from other larger scale studies by identifying that households further from markets had higher fishing frequency. We highlight the role of middlemen in these small-scale fisheries, who have been largely overlooked as drivers of fisheries catch. Our findings emphasize the need for household-level analyses to better understand the complexities in coral reef social-ecological systems to more effectively manage small-scale fisheries in communities.

Estimating population sizes and genetic diversity are key factors to understand and predict population dynamics. Marine species have been a difficult challenge in that respect, due to the difficulty in assessing population sizes and the open nature of such populations. Small, isolated islands with endemic species offer an opportunity to groundtruth population size estimates with empirical data and investigate the genetic consequences of such small populations. Here we focus on two endemic species of reef fish, the Clipperton damselfish, Stegastes baldwini, and the Clipperton angelfish, Holacanthus limbaughi, on Clipperton Atoll, tropical eastern Pacific. Visual surveys, performed over almost two decades and four expeditions, and genetic surveys based on genomic RAD sequences, allowed us to estimate kinship and genetic diversity, as well as to compare population size estimates based on visual surveys with effective population sizes based on genetics. We found that genetic and visual estimates of population numbers were remarkably similar. S. baldwini and H. limbaughi had population sizes of approximately 800,000 and 60,000, respectively. Relatively small population sizes resulted in low genetic diversity and the presence of apparent kinship. This study emphasizes the importance of small isolated islands as models to study population dynamics of marine organisms.

International audience; Coral reefs provide ecosystem goods and services for millions of people in the tropics, but reef conditions are declining worldwide. Effective solutions to the crisis facing coral reefs depend in part on understanding the context under which different types of conservation benefits can be maximized. Our global analysis of nearly 1,800 tropical reefs reveals how the intensity of human impacts in the surrounding seascape, measured as a function of human population size and accessibility to reefs ("gravity"), diminishes the effectiveness of marine reserves at sustaining reef fish biomass and the presence of top predators, even where compliance with reserve rules is high. Critically, fish biomass in high-compliance marine reserves located where human impacts were intensive tended to be less than a quarter that of reserves where human impacts were low. Similarly, the probability of encountering top predators on reefs with high human impacts was close to zero, even in high-compliance marine reserves. However, we find that the relative difference between openly fished sites and reserves (what we refer to as conservation gains) are highest for fish biomass (excluding predators) where human impacts are moderate and for top predators where human impacts are low. Our results illustrate critical ecological trade-offs in meeting key conservation objectives: reserves placed where there are moderate-to-high human impacts can provide substantial conservation gains for fish biomass, yet they are unlikely to support key ecosystem functions like higher-order predation, which is more prevalent in reserve locations with low human impacts. marine reserves | fisheries | coral reefs | social-ecological | socioeconomic T he world's coral reefs are rapidly degrading (1-3), which is diminishing ecological functioning and potentially affecting the well-being of the millions of people with reef-dependent livelihoods (4). Global climate change and local human impacts (such as fishing) are pervasive drivers of reef degradation (1, 5). In Significance Marine reserves that prohibit fishing are a critical tool for sustaining coral reef ecosystems, yet it remains unclear how human impacts in surrounding areas affect the capacity of marine reserves to deliver key conservation benefits. Our global study found that only marine reserves in areas of low human impact consistently sustained top predators. Fish biomass inside marine reserves declined along a gradient of human impacts in surrounding areas; however, reserves located where human impacts are moderate had the greatest difference in fish biomass compared with openly fished areas. Reserves in low human-impact areas are required for sustaining ecological functions like high-order predation, but reserves in high-impact areas can provide substantial conservation gains in fish biomass.

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

Here we report on two new reef fish species from the remote and isolated Easter Island—the striped boarfish Evistias acutirostris and the ornate butterflyfish Chaetodon ornatissimus were observed during scuba dives and underwater video around Easter Island, as well as at nearby Apolo Seamount. These observations are the first records of these species for the southeastern Pacific, which represents a major extension to their distributions and raises questions about the origins and persistence of reef fishes in remote subtropical locations.

Bonefishes are a cryptic species complex that are a prized sportfish in many places around the world. In Hawai‘i they have a long history of use and today have important recreational, and cultural value. In the early 1980s, two distinct species of bonefishes were determined to inhabit Hawaiian waters (Albula glossodonta “round jaw”, and A. virgata “sharp jaw”). Little is known about the life histories of these two species, hindering population assessments and relevant fisheries management guidelines. In addition, no ecological studies have been conducted to examine interactions or separation between these species. This research assesses how differences in size, abundance, diet, growth, reproduction, and habitat preference of the two bonefish species in Hawai‘i can explain the coexistence and persistence of these two closely related species. Differences in size structure, growth rates, and spawning patterns for each species provides species-specific life history information that differentiates them ecologically and is useful for population assessments and in developing species-specific management strategies. We found that the wide-ranging species, A. glossodonta had a larger mean size, length at a given weight, and size at maturity than the endemic, A. virgata. We found differences in prey preferences between the two species that support our hypothesis that differences in jaw morphologies and habitat preferences translate to dissimilarities in diet. This study contributes to our knowledge about these species and provides an example of niche specialization in two closely related and cohabiting species.

Bonefishes in Hawai’i have had a cultural and subsistence importance since the early Hawaiians harvested and raised them. Today, the recreational fishery for bonefishes in Hawai’i continues to expand while the commercial fishery has witnessed a 99 % decline in landings over the past century. The ‘Ō‛io Tagging Project arose with a consensus that collecting biological and fisheries data on bonefishes is essential for properly managed resources, but engaging and disseminating this knowledge back to resource users is equally as important. Since 2003, 770 anglers have recorded >10,600 fishing hours, while tagging 3420 and recapturing 67 bonefishes. Tagged bonefishes exhibited extremely high site fidelity, with the majority recaptured

Continuing degradation of coral reef ecosystems has generated substantial interest in how management can support reef resilience(1,2). Fishing is the primary source of diminished reef function globally(3-5), leading to widespread calls for additional marine reserves to recover fish biomass and restore key ecosystem functions(6). Yet there are no established baselines for determining when these conservation objectives have been met or whether alternative management strategies provide similar ecosystem benefits. Here we establish empirical conservation benchmarks and fish biomass recovery timelines against which coral reefs can be assessed and managed by studying the recovery potential of more than 800 coral reefs along an exploitation gradient. We show that resident reef fish biomass in the absence of fishing (B-0) averages similar to 1,000 kg ha(-1), and that the vast majority (83%) of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions such as predation. Given protection from fishing, reef fish biomass has the potential to recover within 35 years on average and less than 60 years when heavily depleted. Notably, alternative fisheries restrictions are largely (64%) successful at maintaining biomass above 50% of B-0, sustaining key functions such as herbivory. Our results demonstrate that crucial ecosystem functions can be maintained through a range of fisheries restrictions, allowing coral reef managers to develop recovery plans that meet conservation and livelihood objectives in areas where marine reserves are not socially or politically feasible solutions.

Sustainable fisheries management is key to restoring and maintaining ecological function and benefits to people, but it requires accurate information about patterns in resource use, particularly fishing pressure. In most coral reef fisheries and other data-poor contexts, obtaining such information is challenging and remains an impediment to effective management. We developed the most comprehensive regional view of shore-based fishing effort and catch for the Hawaiian Islands to show detailed fishing patterns from across the main Hawaiian Islands (MHI). We reveal these regional patterns through fisher “creel” surveys conducted through collaborative efforts by local communities, state agencies, academics, and environmental organizations, at 18 sites and comprising >10,000 hr of monitoring across a range of habitats and human influences throughout the MHI. Here, we document spatial patterns in nearshore fisheries catch, effort, catch rates (i.e., catch-per-unit-effort [CPUE]), and catch disposition (i.e., use of fish after catch is landed). Line fishing was consistently the most commonly employed gear type (94%), followed by net fishing. The most efficient gear types (i.e., higher CPUE) were spear (0.64 kg hr-1), followed closely by net (0.61 kg hr-1), with CPUE for line (0.16 kg hr-1) 3.9 times lower than spear and 3.7 times lower than net. Creel surveys also reveal rampant illegal fishing activity across the studied locations. Surprisingly, overall, most of the catch was not sold, but rather retained for home consumption or given away to extended family, which indicates that cultural and food security may be stronger drivers of fishing effort than commercial exploitation for nearshore coral reef fisheries in Hawai‘i. Increased monitoring of spatial patterns in nearshore fisheries can inform targeted management, in order to maintain these fisheries for local communities’ food security, cultural, and ecological value.

Blooms of alien invasive marine algae have become common, greatly altering the health and stability of nearshore marine ecosystems. Concurrently, herbivorous fishes have been severely overfished in many locations worldwide, contributing to increases in macroalgal cover. We used a multi-pronged, interdisciplinary approach to test if higher biomass of herbivorous fishes inside a no-take marine reserve makes this area more resistant to invasive algal overgrowth. Over a two year time period, we (1) compared fish biomass and algal cover between two fished and one unfished patch reef in Hawai’i, (2) used acoustic telemetry to determine fidelity of herbivorous fishes to the unfished reef, and (3) used metabarcoding and next-generation sequencing to determine diet composition of herbivorous fishes. Herbivore fish biomass was significantly higher in the marine reserve compared to adjacent fished reefs, whereas invasive algal cover differed by species. Herbivorous fish movements were largely confined to the unfished patch reef where they were captured. Diet analysis indicated that the consumption of invasive algae varied among fish species, with a high prevalence of comparatively rare native algal species. Together these findings demonstrate that the contribution of herbivores to coral reef resilience, via resistance to invasive algae invasion, is complex and species-specific.

Este artículo contiene 24 páginas, 10 figuras, 6 tablas., The islands of Madeira and Selvagens are less than 300 km apart but offer a clear contrast between a densely populated and highly developed island (Madeira), and a largely uninhabited and remote archipelago (Selvagens) within Macaronesia in the eastern Atlantic. The Madeira Archipelago has ~260,000 inhabitants and receives over six million visitor days annually. The Selvagens Islands Reserve is one of the oldest nature reserves in Portugal and comprises two islands and several islets, including the surrounding shelf to a depth of 200 m. Only reserve rangers and a small unit of the maritime police inhabit these islands. The benthic community around Selvagens was dominated by erect and turf algae, while the community at Madeira was comprised of crustose coralline and turf algae, sessile invertebrates, and sea urchin barrens. The sea urchin Diadema africanum was 65% more abundant at Madeira than at Selvagens. Total fish biomass was 3.2 times larger at Selvagens than at Madeira, and biomass of top predators was more than 10 times larger at Selvagens. Several commercially important species (e.g., groupers, jacks), which have been overfished throughout the region, were more common and of larger size at Selvagens than at Madeira. Important sea urchin predators (e.g., hogfishes, triggerfishes) were also in higher abundance at Selvagens compared to Madeira. The effects of fishing and other anthropogenic influences are evident around Madeira. This is in stark contrast to Selvagens, which harbors healthy benthic communities with diverse algal assemblages and high fish biomass, including an abundance of large commercially important species. The clear differences between these two island groups highlights the importance of expanding and strengthening the protection around Selvagens, which harbors one of the last intact marine ecosystems in the North Atlantic, and the need to increase management and protection around Madeira., Fundação para a Ciência e a Tecnologia (FCT) supported this work under the strategic project UID/MAR/04292/2013.

1. Despite increasing policies of protection, few localities in the Caribbean remain spared from human impacts. These lightly affected areas can better reflect the past composition of reef fish assemblages and provide baseline information about the natural factors driving fish distributions in the region. 2. Reef fish assemblage structures were analysed in 21 Caribbean fished areas and marine protected areas (MPAs) along a gradient of distance to the nearest major market place. Assemblage structures by size and by trophic group were significantly related to the distance to market. 3. Relationships of reef fish life-history traits, families, and vulnerability indicators were examined with the seascape and the benthic composition at Los Roques Archipelago, the most isolated MPA in the analysis. Factors linked to seascape features were more important than benthic composition or human activities in explaining fish assemblage structure. 4. Wave exposure was the most influential seascape metric. Exposed habitats were dominated by octocorals and sponges. More sheltered habitats were characterized by high coral cover, while leeward sites were characterized by steep slopes with close proximity to deeper water. 5. Exposed habitats were mostly occupied by unspecialized fish species. Piscivore densities were high at south and south-west sites, and were likely related to the large concentrations of planktivorous fishes found there. South and south-west sites experience full oceanic conditions, and supported the highest species richness and densities within the archipelago. 6. Los Roques National Park is one of the oldest and most remote Caribbean MPAs. Its fish assemblage structure is healthier than other fished or protected areas, with higher species richness, higher density of piscivores, and an abundance of large species. Predator–prey relationships provided additional evidence that Los Roques reef fish assemblage presented specific characteristics. 7. The main patterns observed in this study represent a baseline for assessing reef fish assemblages elsewhere in the southern Caribbean.

Este artículo contiene 18 páginas, 3 tablas, 7 figuras., Palau has a rich heritage of conservation that has evolved from the traditional moratoria on fishing, or ªbulº, to more western Marine Protected Areas (MPAs), while still retaining elements of customary management and tenure. In 2003, the Palau Protected Areas Network (PAN) was created to conserve Palau's unique biodiversity and culture, and is the country's mechanism for achieving the goals of the Micronesia Challenge (MC), an initiative to conserve 30% of near-shore marine resources within the region by 2020. The PAN comprises a network of numerous MPAs within Palau that vary in age, size, level of management, and habitat, which provide an excellent opportunity to test hypotheses concerning MPA design and function using multiple discreet sampling units. Our sampling design provided a robust space for time comparison to evaluate the relative influence of potential drivers of MPA efficacy. Our results showed that no-take MPAs had, on average, nearly twice the biomass of resource fishes (i.e. those important commercially, culturally, or for subsistence) compared to nearby unprotected areas. Biomass of non-resource fishes showed no differences between no-take areas and areas open to fishing. The most striking difference between notake MPAs and unprotected areas was the more than 5-fold greater biomass of piscivorous fishes in the MPAs compared to fished areas. The most important determinates of no-take MPA success in conserving resource fish biomass were MPA size and years of protection. Habitat and distance from shore had little effect on resource fish biomass. The extensive network of MPAs in Palau likely provides important conservation and tourism benefits to the Republic, and may also provide fisheries benefits by protecting spawning aggregation sites, and potentially through adult spillover., This work was supported by the National Geographic Society, www.nationalgeographic.com, ES; Blancpain, http://www.blancpain.com/, ES; Davidoff Cool Water, http://www.zinodavidoff. com/, ES; Jynwel Foundation, jynwelfoundation. org, ES; The Leona M. and Harry B. Helmsley Charitable Trust, www.helmsleytrust.org, ES; Lindblad Expeditions, www.expeditions.com, ES.

When tropical systems lose species, they are often assumed to be buffered against declines in functional diversity by the ability of the species-rich biota to display high functional redundancy: i.e., a high number of species performing similar functions. We tested this hypothesis using a ninefold richness gradient in global fish faunas on tropical reefs encompassing 6,316 species distributed among 646 functional entities (FEs): i.e., unique combinations of functional traits. We found that the highest functional redundancy is located in the Central Indo-Pacific with a mean of 7.9 species per FE. However, this overall level of redundancy is disproportionately packed into few FEs, a pattern termed functional over-redundancy (FOR). For instance, the most speciose FE in the Central Indo-Pacific contains 222 species (out of 3,689) whereas 38% of FEs (180 out of 468) have no functional insurance with only one species. Surprisingly, the level of FOR is consistent across the six fish faunas, meaning that, whatever the richness, over a third of the species may still be in overrepresented FEs whereas more than one third of the FEs are left without insurance, these levels all being significantly higher than expected by chance. Thus, our study shows that, even in high-diversity systems, such as tropical reefs, functional diversity remains highly vulnerable to species loss. Although further investigations are needed to specifically address the influence of redundant vs. vulnerable FEs on ecosystem functioning, our results suggest that the promised benefits from tropical biodiversity may not be as strong as previously thought.

Fishes contribute substantially to energy and nutrient fluxes in reef ecosystems, but quantifying these roles is challenging. Here, we do so by synthesising a large compilation of fish metabolic-rate data with a comprehensive database on reef-fish community abundance and biomass. Individual-level analyses support predictions of Metabolic Theory after accounting for significant family-level variation, and indicate that some tropical reef fishes may already be experiencing thermal regimes at or near their temperature optima. Community-level analyses indicate that total estimated respiratory fluxes of reef-fish communities increase on average ~2-fold from 22 to 28 °C. Comparisons of estimated fluxes among trophic groups highlight striking differences in resource use by communities in different regions, perhaps partly reflecting distinct evolutionary histories, and support the hypothesis that piscivores receive substantial energy subsidies from outside reefs. Our study demonstrates one approach to synthesising individual- and community-level data to establish broad-scale trends in contributions of biota to ecosystem dynamics.

Although ambient biological underwater sound was first characterized more than 60 years ago, attributing specific components of ambient sound to their creators remains a challenge. Noise produced by snapping shrimp typically dominates the ambient spectra near tropical coasts, but significant unexplained spectral variation exists. Here, evidence is presented indicating that a discernible contribution to the ambient sound field over coral reef ecosystems in the Line Islands archipelago originates from the interaction of hard-shelled benthic macro-organisms with the coral substrate. Recordings show a broad spectral peak centered between 14.30 and 14.63 kHz, incoherently added to a noise floor typically associated with relatively "white" snapping shrimp sounds. A 4.6 to 6.2 dB increase of pressure spectral density level in the 11 to 17 kHz band occurs simultaneously with an increase in benthic invertebrate activity at night, quantified through time-lapse underwater photography. Spectral-level-filtered recordings of hermit crabs Clibanarius diugeti in quiet aquarium conditions reveal that transient sounds produced by the interaction between the crustaceans' carapace, shell, and coral substrate are spectrally consistent with Line Islands recordings. Coral reef ecosystems are highly interconnected and subtle yet important ecological changes may be detected quantitatively through passive monitoring that utilizes the acoustic byproducts of biological activity.

Reef-fish management and conservation is hindered by a lack of information on fish populations prior to large-scale contemporary human impacts. As a result, relatively pristine sites are often used as conservation baselines for populations near sites affected by humans. This space-for-time approach can only be validated by sampling assemblages through time. We used archaeological remains to evaluate whether the remote, uninhabited Northwestern Hawaiian Islands (NWHI) might provide a reasonable proxy for a lightly exploited baseline in the Main Hawaiian Islands (MHI). We used molecular and morphological techniques to describe the taxonomic and size composition of the scarine parrotfish catches present in 2 archaeological assemblages from the MHI, compared metrics of these catches with modern estimates of reproductive parameters to evaluate whether catches represented by the archaeological material were consistent with sustainable fishing, and evaluated overlap between size structures represented by the archaeological material and modern survey data from the MHI and the NWHI to assess whether a space-for-time substitution is reasonable. The parrotfish catches represented by archaeological remains were consistent with sustainable fishing because they were dominated by large, mature individuals whose average size remained stable from prehistoric (AD approximately 1400-1700) through historic (AD 1700-1960) periods. The ancient catches were unlike populations in the MHI today. Overlap between the size structure of ancient MHI catches and modern survey data from the NWHI or the MHI was an order of magnitude greater for the NWHI comparison, a result that supports the validity of using the NWHI parrotfish data as a proxy for the MHI before accelerated, heavy human impacts in modern times.

International audience; High species richness is thought to support the delivery of multiple ecosystem functions and services under changing environments. Yet, some species might perform unique functional roles while others are redundant. Thus, the benefits of high species richness in maintaining ecosystem functioning are uncertain if functions have little redundancy, potentially leading to high vulnerability of functions. We studied the natural propensity of assemblages to be functionally buffered against loss prior to fishing activities, using functional trait combinations, in coral reef fish assemblages across unfished wilderness areas of the Indo-Pacific: Chagos Archipelago, New Caledonia and French Polynesia. Fish functional diversity in these wilderness areas is highly vulnerable to fishing, explained by species- and abundance-based redundancy packed into a small combination of traits, leaving most other trait combinations (60%) sensitive to fishing, with no redundancy. Functional vulnerability peaks for mobile and sedentary top predators, and large species in general. Functional vulnerability decreases for certain functional entities in New Caledonia, where overall functional redundancy was higher. Uncovering these baseline patterns of functional vulnerability can offer early warning signals of the damaging effects from fishing, and may serve as baselines to guide precautionary and even proactive conservation actions.

Small-scale fisheries across the globe provide critical food security, livelihoods, and human well-being, but are threatened by a combination of local and global stressors, including overexploitation, pollution, and climate change. Participatory approaches to management, especially those that incorporate local communities and customary knowledge can provide meaningful biological information that supports sustainable fisheries management and builds local adaptive capacity to changing ocean conditions. Through a collaboration between fishers, scientists, NGOs, and regulating agencies, we developed a low-cost, low-tech method to assess the seasonal spawning peaks, lunar spawning cycles, and size at maturity (L50) for key targeted reef fish, combining traditional knowledge and practice with modern scientific approaches, including gonadosomatic index (GSI) and histology. Two years of community-based monitoring resulted in data from 57 species and 15 families of reef and nearshore fishes (n = 2595), with detailed information for 10 species at 4 locations across the Hawaiian Islands. Comparisons between community-collected GSI data and scientifically (histologically) assessed spawning cycles and size at reproductive maturity produced similar results suggesting that these approaches can be applied in data-poor fisheries to assess spawning seasons and size at maturity (L50), both of which are critical needs for effective fisheries management. Semistructured surveys revealed a large body of local knowledge on spawning times and harvest practices based on allowing spawning to occur before harvesting and protecting small and large size classes, but little evidence that fishers understand temporal patterns of spawning. This suggests that monitoring methods that fill key gaps such as this and are congruent with these local knowledge systems and customary harvest practices may be key for local stewardship and adaptive management.

Este artículo contiene 24 páginas, 10 figuras, 1 tabla., Clipperton Atoll (Île de La Passion) is the only atoll in the Tropical Eastern Pacific (TEP) ecoregion and, owing to its isolation, possesses several endemic species and is likely an important stepping stone between Oceania, the remainder of the TEP, including other oceanic islands and the west coast of Central America. We describe the biodiversity at this remote atoll from shallow water to depths greater than one thousand meters using a mixture of technologies (SCUBA, stereo baited remote underwater video stations, manned submersible, and deep-sea drop cameras). Seventy-four unique taxa of invertebrates were identified during our expedition. The majority (70%) of these taxa were confined to the top 400 m and consisted mostly of sessile organisms. Decapod crustaceans and black corals (Antipatharia) had the broadest depth ranges, 100 1,497 mand 58 967 m, respectively. Decapods were correlated with the deepest depths, while hard corals were correlated with the shallow depths. There were 96 different fish taxa from 41 families and 15 orders, of which 70% were restricted to depths, This work was supported with funding from The Brooks Foundation, The Keith Campbell Foundation for the Environment, The Case Foundation, Leonardo DiCaprio Foundation, Davidoff, The Don Quixote Foundation, Roger and Rosemary Enrico Foundation, Helmsley Charitable Trust, Lindblad Expeditions-National Geographic Fund, Philip Stephenson Foundation, Vicki and Roger Sant, The Waitt Foundation, and The National Geographic Society.

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

The Hawaiians of old depended on the sea for survival and, as a result, developed a sophisticated understanding of the natural processes regulating resource abundance and effective strategies to manage those resources. After Western contact, sociopolitical upheaval led to the breakdown of the traditional Hawaiian fisheries management system, though practice and knowledge continued. Even today, subsistence fishing is culturally and economically important to many communities throughout Hawai‘i, but declining resources over the past century have raised concerns about their sustainability. To confront this issue, a number of communities are currently strengthening local influence and accountability for local marine resources through revitalization of local traditions and resource knowledge. This renaissance of traditional community-based management and rediscovery of traditional techniques offers great promise for improving the condition of Hawai‘i's coastal marine environment and the management of its fisheries.

Marine protected areas (MPAs) can benefit fisheries through export of pelagic eggs and larvae and the net emigration of adults and juveniles (spillover). Spillover was investigated for a marine protected area on the north shore of Oahu, Hawai‘i utilizing a seascape approach. This study incorporated habitat variables and underwater visual surveys of fishes and benthos measured at two distinct scales (125 m 2 and 1000 m 2 ) inside and outside the protected area at varying distance from the boundary. The relationship between fish biomass from fine-scale surveys and key habitat variables was found to account for a large portion of the variability for both resource (targeted) fish species (15%) and non-resource fish (28%). The remaining variation in resource fish biomass was significantly correlated with distance from the MPA boundary showing a decreasing gradient from inside to outside ( r 2 = 0.46, p = 0.001), indicating fish spillover at a local scale ( p = 0.45). The evidence of spillover based on the fine-scale surveys was corroborated by results from broad-scale surveys, which also showed a significant relationship ( r 2 = 0.19, p

In the marine realm, the tropics host an extraordinary diversity of taxa but the drivers underlying the global distribution of marine organisms are still under scrutiny and we still lack an accurate global predictive model. Using a spatial database for 6336 tropical reef fishes, we attempted to predict species richness according to geometric, biogeographical and environmental explanatory variables. In particular, we aimed to evaluate and disentangle the predictive performances of temperature, habitat area, connectivity, mid-domain effect and biogeographical region on reef fish species richness. We used boosted regression trees, a flexible machine-learning technique, to build our predictive model and structural equation modeling to test for potential 'mediation effects' among predictors. Our model proved to be accurate, explaining 80% of the total deviance in fish richness using a cross-validated procedure. Coral reef area and biogeographical region were the primary predictors of reef fish species richness, followed by coast length, connectivity, mid-domain effect and sea surface temperature, with interactions between the region and other predictors. Important indirect effects of water temperature on reef fish richness, mediated by coral reef area, were also identified. The relationship between environmental predictors and species richness varied markedly among biogeographical regions. Our analysis revealed that a few easily accessible variables can accurately predict reef fish species richness. They also highlight concerns regarding ongoing environmental declines, with region-specific responses to variation in environmental conditions predicting a variable response to anthropogenic impacts.

An expedition to Salas y Gomez and Easter islands was conducted to develop a comprehensive baseline of the nearshore marine ecosystem, to survey seamounts of the recently created Motu Motiro Hiva Marine Park (MMHMP) – a no-take marine reserve of 150 000 km2 – and to compare these results with Easter Island where the marine ecosystem is similar but has no marine protection. Live coral cover was surprisingly high at both Easter Island (53%) and Salas y Gomez (44%), especially considering their sub-tropical location, high wave energy environments, and geographic isolation. Endemic and regionally-endemic species comprised 77% of the fish abundance at Easter Island and 73% at Salas y Gomez. Fish biomass at Salas y Gomez was relatively high (1.2 t ha-1) and included a large proportion of apex predators (43%), whereas at Easter Island it was almost three times lower (0.45 t ha-1) with large predators accounting for less than 2% of the biomass, despite good habitat quality. The large cohort of small sharks and the absence of larger sharks at Salas y Gomez suggest mesopredator release consistent with recent shark fishing. The fish fauna at the seamounts between Easter Island and Salas y Gomez, outside of MMHMP, harboured 46% endemic species, including a new species of damselfish (Chromis sp. nov.) and probably a new species of Chimaera (Hydrolagus). Numerous seamounts adjacent to Salas y Gomez are currently not included in the MMHMP. This expedition highlights the high biodiversity value of this remote part of the Pacific owing to the uniqueness (endemicity) of the fauna, large apex predator biomass, and geographic isolation. Copyright © 2013 John Wiley & Sons, Ltd.

This study took advantage of a unique opportunity to collect large sample sizes of a coral reef fish species across a range of physical and biological features of the Hawaiian Archipelago to investigate variability in the demography of an invasive predatory coral reef fish, Cephalopholis argus (Family: Epinephelidae). Age-based demographic analyses were conducted at 10 locations in the main Hawaiian Islands and estimates of weight-at-length, size-at-age, and longevity were compared among locations. Each metric differed among locations, although patterns were not consistent across metrics. Length-weight relationships for C. argus differed among locations and individuals weighed less at a given length at Hilo, the southernmost location studied. Longevity differed among and within islands and was greater at locations on Maui and Hawaii compared to the more northern locations on Oahu and Kauai. Within-island growth patterns differed at Kauai, Oahu, and Hawaii. This work provides a case study of fundamental life history information from distant and/or spatially limited locations that are critical for developing robust fishery models. The differences observed both among and within islands indicate that variability may be driven by cross-scale mechanisms that need to be considered in fisheries stock assessments and ecosystem-based management.

A process-orientated understanding of ecosystems usually starts with an exploratory analysis of empirical relationships among potential drivers and state variables. While relationships among herbivory, algal cover, and coral recruitment, have been explored in the Caribbean, the nature of such relationships in the Pacific appears to be variable or unclear. Here, we examine potential drivers structuring the benthos and herbivorous fish assemblages of outer-shelf reefs in Micronesia (Palau, Guam and Pohnpei). Surveys were stratified by wave exposure and protection from fishing. High biomass of most herbivores was favoured by high wave exposure. High abundance of large-bodied scarids was associated with low turf abundance, high coral cover, and marine reserves. The remaining herbivores were more abundant in reefs with low coral cover, possibly because space and hence food limitation occur in high-coral-cover reefs. Rugosity had no detectable effect on herbivorous fish abundance once differences in exposure and coral cover were accounted for. At identical depths, high wave exposure was associated with greater volumes (cover × canopy height) of macroalgae and algal turfs, which most likely resulted from high primary productivity driven by flow. In exposed areas, macroalgal cover declined as the acanthurid biomass increased. The volume of algal turfs was negatively associated with coral cover and herbivore biomass. In turn, high coral cover and herbivore biomass are likely to intensify grazing. The density of juvenile corals was variable where macroalgal cover was low but was confined to lower densities where macroalgal cover was high. High coral cover and density of juvenile corals were favoured in sheltered habitats. While a weak positive relationship was found between scarid biomass and juvenile coral density, we hypothesise that high scarid densities may hinder juvenile density through increased corallivory. New hypotheses emerged that will help clarify the role of acanthurids, wave exposure, and corallivory in driving the recovery of Pacific coral communities.

18 páginas, 7 figuras, 5 tablas, [EN]Fishes at Isla del Coco National Park, Costa Rica, were surveyed as part of a larger scientific expedition to the area in September 2009. The average total biomass of nearshore fishes was 7.8 tonnes per ha, among the largest observed in the tropics, with apex predators such as sharks, jacks, and groupers accounting for nearly 40% of the total biomass. The abundance of reef and pelagic sharks, particularly large aggregations of threatened species such as the scalloped hammerhead shark (up to 42 hammerheads ha-1) and large schools of jacks and snappers show the capacity for high biomass in unfished ecosystems in the Eastern Tropical Pacific. However, the abundance of hammerhead and reef whitetip sharks appears to have been declining since the late 1990s, and likely causes may include increasing fishing pressure on sharks in the region and illegal fishing inside the Park. One Galapagos shark tagged on September 20, 2009 in the Isla del Coco National Park moved 255km southeast towards Malpelo Island in Colombia, when it stopped transmitting. These results contribute to the evidence that sharks conduct large-scale movements between marine protected areas (Isla del Coco, Malpelo, Galápagos) in the Eastern tropical Pacific and emphasize the need for regional-scale management. More than half of the species and 90% of the individuals observed were endemic to the tropical eastern Pacific. These high biomass and endemicity values highlight the uniqueness of the fish assemblage at Isla del Coco and its importance as a global biodiversity hotspot.[ES]La biomasa promedio de peces costeros en el Parque Nacional Isla del Coco en septiembre de 2010 fue de 7,8 toneladas por hectárea, entre las más elevadas halladas jamás en zonas tropicales. Los grandes depredadores representaron el 40% de la biomasa total. La abundancia de tiburones costeros y pelágicos, particularmente las enormes agregaciones de tiburón martillo (hasta 42 individuos por hectárea) y los extensos bancos de carángidos y lutjánidos, muestran la capacidad que tienen los ecosistemas marinos no pescados para albergar elevadas biomasas de peces, y hacen de la Isla del Coco un lugar único en el mundo. No obstante, la abundancia de tiburones parece estar decreciendo desde 1999, probablemente a causa de la creciente presión pesquera en la región y la pesca ilegal en el interior del Parque. Un tiburón de Galápagos marcado se dirigió 255km en dirección a la Isla de Malpelo, Colombia. Estos resultados sugieren que los tiburones realizan importantes movimientos entre áreas marinas protegidas (Isla del Coco, Malpelo, Galápagos) en el Pacífico Tropical Oriental y remarcan la necesidad de una gestión regional de estos animales. Más del 50% de las especies y el 90% de individuos observados en los contajes eran endémicos del Pacífico Tropical Oriental.

© 2016 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Ongoing declines in the structure and function of the world's coral reefs require novel approaches to sustain these ecosystems and the millions of people who depend on them. A presently unexplored approach that draws on theory and practice in human health and rural development is to systematically identify and learn from the 'outliers' - places where ecosystems are substantially better ('bright spots') or worse ('dark spots') than expected, given the environmental conditions and socioeconomic drivers they are exposed to. Here we compile data from more than 2,500 reefs worldwide and develop a Bayesian hierarchical model to generate expectations of how standing stocks of reef fish biomass are related to 18 socioeconomic drivers and environmental conditions. We identify 15 bright spots and 35 dark spots among our global survey of coral reefs, defined as sites that have biomass levels more than two standard deviations from expectations. Importantly, bright spots are not simply comprised of remote areas with low fishing pressure; they include localities where human populations and use of ecosystem resources is high, potentially providing insights into how communities have successfully confronted strong drivers of change. Conversely, dark spots are not necessarily the sites with the lowest absolute biomass and even include some remote, uninhabited locations often considered near pristine. We surveyed local experts about social, institutional, and environmental conditions at these sites to reveal that bright spots are characterized by strong sociocultural institutions such as customary taboos and marine tenure, high levels of local engagement in management, high dependence on marine resources, and beneficial environmental conditions such as deep-water refuges. Alternatively, dark spots are characterized by intensive capture and storage technology and a recent history of environmental shocks. Our results suggest that investments in strengthening fisheries governance, particularly aspects such as participation and property rights, could facilitate innovative conservation actions that help communities defy expectations of global reef degradation.

In 2007, due to growing concerns of declines in nearshore fisheries in Hawai‘i, a ban on gillnets was implemented in designated areas around the island of O‘ahu in the main Hawaiian Islands. Utilizing a 17 year time-series of juvenile fish abundance beginning prior to the implementation of the gillnet ban, we examined the effects of the ban on the abundance of juveniles of soft-bottom associated fish species. Using a Before-After-Control-Impact (BACI) sampling design, we compared the abundance of targeted fishery species in a bay where gillnet fishing was banned (Kailua, O‘ahu), and an adjacent bay where fishing is still permitted (Waimānalo, O‘ahu). Our results show that when multiple juvenile fish species were combined, abundance declined over time in both locations, but the pattern varied for each of the four species groups examined. Bonefishes were the only species group with a significant BACI effect, with higher abundance in Kailua in the period after the gillnet ban. This study addressed a need for scientific assessment of a fisheries regulation that is rarely possible due to lack of quality data before enactment of such restrictions. Thus, we developed a baseline status of juveniles of an important fishery species, and found effects of a fishery management regulation in Hawai‘i.

Overfishing has dramatically depleted sharks and other large predatory fishes worldwide except for a few remote and/or well-protected areas. The islands of Darwin and Wolf in the far north of the Galapagos Marine Reserve (GMR) are known for their large shark abundance, making them a global scuba diving and conservation hotspot. Here we report quantitative estimates of fish abundance at Darwin and Wolf over two consecutive years using stereo-video surveys, which reveal the largest reef fish biomass ever reported (17.5 t \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}${\mathrm{ha}}^{-1}$\end{document}ha−1 on average), consisting largely of sharks. Despite this, the abundance of reef fishes around the GMR, such as groupers, has been severely reduced because of unsustainable fishing practices. Although Darwin and Wolf are within the GMR, they were not fully protected from fishing until March 2016. Given the ecological value and the economic importance of Darwin and Wolf for the dive tourism industry, the current protection should ensure the long-term conservation of this hotspot of unique global value.

22 páginas, 6 figuras, 1 tabla., We examined diatom assemblages from 18 stream and pond samples in the Franz Josef Land Archipelago (FJL), the most northern land of Eurasia. More than 216 taxa were observed, revealing a rich circumpolar diatom flora, including many undescribed taxa. Widely distributed taxa were the most abundant by cell densities, while circumpolar taxa were the most species rich. Stream and pond habitats hosted different assemblages, and varied along a pH gradient. Diatoma tenuis was the most abundant and ubiquitous taxon. However, several circumpolar taxa such as Chamaepinnularia gandrupii, Cymbella botellus, Psammothidium sp. and Humidophila laevissima were also found in relatively high abundances. Aerophilic taxa were an important component of FJL diatom assemblages (Humidophila spp., Caloneis spp. and Pinnularia spp.), reflecting the large and extreme seasonal changes in Arctic conditions.Wepredict a decrease in the abundance of circumpolar taxa, an increase in local ( -) freshwater diatom diversity, but a decrease in regional diversity (circumpolar homogenization) as a result of current warming trends and to a lesser extent the increasing human footprint in the region., Funding for this work was provided by National Geographic, Blancpain, Davidoff Cool Water, the Russian Arctic National Park, the Russian Geographical Society, and the State Nature Reserve Franz Josef Land. A supporting Canadian RAC (2015 2017) grant to PBH was used to complete taxonomic SEM and LM investigations. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

The regionally endemic Galapagos Grouper, locally known as bacalao, is one of the most highly prized finfish species within the Galapagos Marine Reserve (GMR). Concerns of overfishing, coupled with a lack of fishing regulations aimed at this species raises concerns about the current population health. We assessed changes in population health over a 30-year period using three simple indicators: (1) percentage of fish below reproductive size (Lm); (2) percentage of fish within the optimum length interval (Lopt); and (3) percentage of mega-spawners in the catch. Over the assessed period, none of the indicators reached values associated with healthy populations, with all indicators declining over time. Furthermore, the most recent landings data show that the vast majority of the bacalao caught (95.7%,) were below Lm, the number of fish within the Lopt interval was extremely low (4.7%), and there were virtually no mega-spawners (0.2%). Bacalao fully recruit to the fishery 15 cm below the size at which 50% of the population matures. The Spawning Potential Ratio is currently 5% of potential unfished fecundity, strongly suggesting severe overfishing. Our results suggest the need for bacalao-specific management regulations that should include minimum (65 cm TL) and maximum (78 cm TL) landing sizes, slot limits (64–78 cm TL), as well as a closed season during spawning from October to January. It is recognized that these regulations are harsh and will certainly have negative impacts on the livelihoods of fishers in the short term, however, continued inaction will likely result in a collapse of this economically and culturally valuable species. Alternative sources of income should be developed in parallel with the establishment of fishing regulations to limit the socio-economic disruption to the fishing community during the transition to a more sustainable management regime.

Group incidence and size are described for recruit parrotfishes, wrasses, and damselfishes on Hawaiian reefs over 3 years (2006–2008) at sites spanning the archipelago (20–28°N, 155–177°W). Coral-poor and coral-rich areas were surveyed at sites with both low (Hawaii Island) and high (Midway Atoll) predator densities, facilitating examination of relations among predator and recruit densities, habitat, and group metrics. Predator and recruit densities varied spatially and temporally, with a sixfold range in total recruit densities among years. Group (≥2 recruits) metrics varied with time and tracked predator and recruit densities and the proportion of schooling species. Groups often included heterospecifics whose proportion increased with group size. A non-saturating relationship between group size and recruit density suggests that the anti-predator benefits of aggregation exceeded competitive costs. Grouping behavior may have overarching importance for recruit survival–even at high recruit densities–and merits further study on Hawaiian reefs and elsewhere.

Spatial pattern metrics have routinely been applied to characterize and quantify structural features of terrestrial landscapes and have demonstrated great utility in landscape ecology and conservation planning. The important role of spatial structure in ecology and management is now commonly recognized, and recent advances in marine remote sensing technology have facilitated the application of spatial pattern metrics to the marine environment. However, it is not yet clear whether concepts, metrics, and statistical techniques developed for terrestrial ecosystems are relevant for marine species and seascapes. To address this gap in our knowledge, we reviewed, synthesized, and evaluated the utility and application of spatial pattern metrics in the marine science literature over the past 30 yr (1980 to 2010). In total, 23 studies characterized seascape structure, of which 17 quantified spatial patterns using a 2-dimensional patch-mosaic model and 5 used a continuously varying 3-dimensional surface model. Most seascape studies followed terrestrial-based studies in their search for ecological patterns and applied or modified existing metrics. Only 1 truly unique metric was found (hydrodynamic aperture applied to Pacific atolls). While there are still relatively few studies using spatial pattern metrics in the marine environment, they have suffered from similar misuse as reported for terrestrial studies, such as the lack of a priori considerations or the problem of collinearity between metrics. Spatial pattern metrics offer great potential for ecological research and environmental management in marine systems, and future studies should focus on (1) the dynamic boundary between the land and sea; (2) quantifying 3-dimensional spatial patterns; and (3) assessing and monitoring seascape change. Included in theme section, "Seascape ecology: application of landscape ecology to the marine environment"

In Palau, Ngerumekaol and Ebiil Channels are spawning aggregation sites that have been protected from fishing since 1976 and 2000, respectively. Groupers and other targeted fisheries species were monitored monthly over a 1.5 year period at these two spawning aggregations and two nearby exploited reference sites where grouper formerly aggregated to spawn. At the protected aggregation sites, three grouper species (Plectropomus areolatus, Epinephelus polyphekadion, and Epinephelus fuscoguttatus) accounted for 78% of the abundance and 85% of the biomass of all resource species surveyed but comprised