Explore the vast range of titles available.

Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40-64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.

Declining natural resources have led to a cultural renaissance across the Pacific that seeks to revive customary ridge-to-reef management approaches to protect freshwater and restore abundant coral reef fisheries. Effective ridge-to-reef management requires improved understanding of land-sea linkages and decision-support tools to simultaneously evaluate the effects of terrestrial and marine drivers on coral reefs, mediated by anthropogenic activities. Although a few applications have linked the effects of land cover to coral reefs, these are too coarse in resolution to inform watershed-scale management for Pacific Islands. To address this gap, we developed a novel linked land-sea modeling framework based on local data, which coupled groundwater and coral reef models at fine spatial resolution, to determine the effects of terrestrial drivers (groundwater and nutrients), mediated by human activities (land cover/use), and marine drivers (waves, geography, and habitat) on coral reefs. We applied this framework in two 'ridge-to-reef' systems (Hā'ena and Ka'ūpūlehu) subject to different natural disturbance regimes, located in the Hawaiian Archipelago. Our results indicated that coral reefs in Ka'ūpūlehu are coral-dominated with many grazers and scrapers due to low rainfall and wave power. While coral reefs in Hā'ena are dominated by crustose coralline algae with many grazers and less scrapers due to high rainfall and wave power. In general, Ka'ūpūlehu is more vulnerable to land-based nutrients and coral bleaching than Hā'ena due to high coral cover and limited dilution and mixing from low rainfall and wave power. However, the shallow and wave sheltered back-reef areas of Hā'ena, which support high coral cover and act as nursery habitat for fishes, are also vulnerable to land-based nutrients and coral bleaching. Anthropogenic sources of nutrients located upstream from these vulnerable areas are relevant locations for nutrient mitigation, such as cesspool upgrades. In this study, we located coral reefs vulnerable to land-based nutrients and linked them to priority areas to manage sources of human-derived nutrients, thereby demonstrating how this framework can inform place-based ridge-to-reef management.

Resource managers in the United States and worldwide are tasked with identifying and mitigating trade-offs between human activities in the deep sea (e.g., fishing, energy development, and mining) and their impacts on habitat-forming invertebrates, including deep-sea corals and sponges (DSCS). Related management decisions require information about where DSCS occur and in what densities. Species distribution modeling (SDM) provides a cost-effective means of identifying potential DSCS habitat over large areas to inform these management decisions and data collection. Here we describe good practices for DSCS SDM, especially in the context of data collection and management applications. Managers typically need information regarding DSCS encounter probabilities, densities, and sizes, defined at sub-regional to basin-wide scales and validated using subsequent, targeted data collections. To realistically achieve these goals, analysts should integrate available data sources in SDMs including fine-scale visual sampling and broad-scale resource surveys (e.g., fisheries trawl surveys), include environmental predictor variables representing multiple spatial scales, model residual spatial autocorrelation, and quantify prediction uncertainty. When possible, models fitted to presence-absence and density data are preferred over models fitted only to presence data, which are difficult to validate and can confound estimated probability of occurrence or density with sampling effort. Ensembles of models can provide robust predictions, while multi-species models leverage information across taxa and facilitate community inference. To facilitate the use of models by managers, predictions should be expressed in units that are widely understood and validated at an appropriate spatial scale using a sampling design that provides strong statistical inference. We present three case studies for the Pacific Ocean that illustrate good practices with respect to data collection, modeling, and validation; these case studies demonstrate it is possible to implement our good practices in real-world settings.

Identifying transport pathways and sources of reef larvae is an essential component of ecosystem science. Ocean drifters tracked by satellite around the Mariana Archipelago were used to evaluate the possible pathways of transport among islands for passive larvae of reef organisms present in the surface layer. Reef taxa vary in their minimum and maximum larval duration from several days to a few months. Drifters leaving the Marianas required more than 16 days of transport prior to arriving near any adjacent island groups. Drifters arriving at the Marianas required more than 35 days of transport before being tracked back to any adjacent island groups. All arrived from the east or southeast via the North Equatorial Current. Roughly 27 % of the drifters that began in the Marianas returned. The majority of returning drifters (65 %) ended to the north of their starting point. Over 70 % of the drifters that returned to the Marianas after starting there did so in less than 40 days. Overall, this suggests that self-seeding may be of great importance to sustaining Mariana reef populations and that position within the archipelago affects connectivity among islands.

Aim Abundant species distribution models (SDMs) of deep‐sea corals and sponges (DSCS) allow one to make community‐level predictions about DSCS. Pairing that with the conservation information of Vulnerable Marine Ecosystems (VMEs) due to their sensitivity to seafloor trawling, one can assess the efficacy of established seafloor protections, known as Essential Fish Habitat and Conservation Areas (trawl closure areas), in the United States West Coast on a multi‐taxon basis. From this, we seek to answer the following questions: (1) can accurate multi‐taxon, trawl‐sensitive DSCS distribution predictions be made for the US West Coast and (2) to what extent do current trawl protections overlap with multi‐taxon distribution predictions and what are the conservation and management implications? Location United States West Coast marine waters. Methods A cluster analysis was run on 40 SDMs of DSCS, identifiable as VME indicators and assigned a VME indicator score based on criteria used by regional fisheries management organisations. SDMs of taxa in clusters were stacked and averaged to produce stacked SDM (S‐SDM) prediction maps. All prediction maps were classified into five habitat suitability classes to facilitate interpretation. The total area within benthic ecoregion‐bathymetric boundaries and the percentage overlap with the bottom trawl closure zone were computed for spatial contextualization and to determine protection coverage for S‐SDMs, respectively. Results Cluster analysis identified 10 groups that represent unique S‐SDMs for the region. Taxa clustered together have previously been documented together in surveys but some novel associations are reported. Geographically, the predicted occurrences can range along the entire western continental margin, be highly restricted, or constrained by recognised biogeographic boundaries. VME indicator metrics ranged from low to moderate. When trawl coverage was computed relative to the suitability's prevalence in the modelling domain, trawl protection was shown to be large for the highest suitability classes for most of the S‐SDMs. Main Conclusions Results indicate the clustering approach has some strengths in identifying known and documented associations between DSCS taxa but some are problematic and produce low to moderate VME indicator scores for S‐SDMs, undercutting the conservation information the metric should convey. Coupled with the small predicted areas of the highest suitability classes, the wholesale recommendation for this approach for management purposes is difficult. We discuss avenues for methodological improvements.

To design effective marine reserves and support fisheries, more information on fishing patterns and impacts for targeted species is needed, as well as better understanding of their key habitats. However, fishing impacts vary geographically and are difficult to disentangle from other factors that influence targeted fish distributions. We developed a set of fishing effort and habitat layers at high resolution and employed machine learning techniques to create regional-scale seascape models and predictive maps of biomass and body length of targeted reef fishes for the main Hawaiian Islands. Spatial patterns of fishing effort were shown to be highly variable and seascape models indicated a low threshold beyond which targeted fish assemblages were severely impacted. Topographic complexity, exposure, depth, and wave power were identified as key habitat variables that influenced targeted fish distributions and defined productive habitats for reef fisheries. High targeted reef fish biomass and body length were found in areas not easily accessed by humans, while model predictions when fishing effort was set to zero showed these high values to be more widely dispersed among suitable habitats. By comparing current targeted fish distributions with those predicted when fishing effort was removed, areas with high recovery potential on each island were revealed, with average biomass recovery of 517% and mean body length increases of 59% on Oahu, the most heavily fished island. Spatial protection of these areas would aid recovery of nearshore coral reef fisheries.

Orbicellid corals are threatened primary reef-building corals throughout the Caribbean in shallow and mesophotic coral ecosystems (MCEs), yet a poor understanding of where they occur limits population monitoring and management. The goals of this study were to predict suitable habitat for orbicellid coral species and to identify how abiotic environmental factors constrain that habitat on the eastern Puerto Rico Shelf. The probability of occurrence for Orbicella annularis and O. faveolata/O. franksi (combined) from shallow to mesophotic depths on the eastern Puerto Rico Shelf was predicted using maximum entropy models. Contributions of abiotic predictors, including bathymetry, seafloor topography, temperature, wave exposure, and bottom velocity, were assessed. Model performance was assessed using area under the receiver operating characteristic curve, standard error of the replicate model runs, and mean absolute error. Both O. annularis and O. faveolata/O. franksi distributions were best predicted by rugosity, temperature, and wave exposure. O. faveolata/O. franksi occurred at shallow and mesophotic depths, and acted as a proxy for identifying the spatial extent of MCEs, contrary to O. annularis, which was predicted at shallow depths. Results for O. faveolata/O. franksi in mesophotic depths indicated potential for large areas of unexplored and unmonitored MCEs along the southeast shelf of St. Thomas, US Virgin Islands and within the Virgin Passage. These spatial predictions of potential mesophotic reef habitats will provide direction for future MCE exploration efforts.

Many coral reef organisms possess a pelagic larval phase during which some larvae are retained near spawning sites and others are dispersed to more distant locations via ocean currents. Planktonic duration, distances traveled, and recruitment success can vary due to natural development rate, mortality rate, and sensory and swimming capabilities of particular taxa. Elevated water temperatures and acidification due to climate change can also influence recruitment by generally accelerating metabolism and growth, raising mortality rate, impairing development of calcified structures, and reducing sensory capabilities. We used hydrodynamic models and drifter data to investigate these various life history and climate-related influences on larval connectivity in and around the Samoan Archipelago. In general, virtual larvae spawned in the Samoan Archipelago seeded their natal reefs with relatively short-lived larvae, and their island neighbors to the west with longer-lived larvae. Larval duration, mortality rate, and sensory zone variables all had a significant effect on connectivity. Effect size was largest for mortality rate followed by larval duration. Shortened larval longevity due to climate change reduced interisland connectivity and changed the life history traits (and therefore taxa) that result in successful connections. Islands will generally become increasingly more reliant on self-seeding as the ocean warms, although the role of most islands primarily as a source or destination was robust to climate change.

Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40-64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.

Cethromycin combines a quinoline nucleus and a macrolide for broad spectrum antibacterial and antiprotozoan activity. Here we characterized the murine pharmacokinetics and lifecycle stage pharmacodynamics for the cethromycin base. Liver pharmacokinetic studies in mice show peak mM drug levels in the liver with 20 hour sustained levels above 10 μM. Peak concentrations in the liver were double the lung and about 440 times that of plasma. Immunofluorescence imaging of cethromycin-treated infected hepatocytes shows complete ablation of the apicoplast. We observed complete cure of liver stage infection by single oral dose of 60 mg/kg in mice which is equivalent to the 5 mg/kg human dose of 300 mg a day used in bacterial pneumonia studies. Cethromycin at 60 mg/kg daily for 7 days was curative in the high parasitemic mouse model. Both mosquito membrane feeding of gametocytes incubated with 20 μM cethromycin and oral dosing in mice demonstrated no decrease in oocyst numbers. Cethromycin has been evaluated for efficacy against bacterial pneumonia in more than 5,000 patients with good safety profiles. Cethromycin has potential for rapid clinical development for casual malaria prophylaxis and possibly radical cure of dormant liver .