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Recent policy recommendations have highlighted the nutritional benefits of fisheries that capture small finfish species. Small fish, particularly those that feed in the pelagic zone, tend to be more nutrient dense than larger species, with increased concentrations of calcium, zinc, and omega-3 fatty acids. However, capturing fish below some recommended size limit (i.e., length at first maturity = L mat) in coral reefs is frequently considered to be unsustainable and associated with reduced yields and losses of ecosystem functions. To evaluate the potential effects of fish body size, we analyzed nutrient concentrations of 424 demersal and pelagic finfish species reported from Western Indian Ocean artisanal fisheries. We found that length and food source are associated with only small differences in nutrient density in the artisanal catches of this region (≤7% of a child's daily requirement in most cases). We also analyzed 20 years of catch monitoring data from Kenya, where many of the common species have L mat ∼20–25 cm, to test the potential benefits and tradeoffs of capturing small fishes. Small capture sizes were associated with low yields and sexually immature catches with a mean length of 15 cm resulting in 38% lower catch per unit effort, 37% lower nutrient yield, and a 22% lower maturity index compared to a mean body length of 30 cm. Catches of undersized fish were not associated with substantial increases or decreases in nutrient content relative to human nutritional requirements. Thus, coral reef artisanal fisheries should target moderate to large fishes (>20 cm) to maximize overall yield, nutrient yield, and sustainability. [Display omitted] • On coral reefs, small fishes are not always more nutritious than large ones. • Small capture sizes are not associated with increased nutrient density. • Large capture sizes are associated with increased yields and nutrient production. • Managers should balance quantity, quality, and sustainability of harvest strategies. [ABSTRACT FROM AUTHOR]

The gamma-ray spectrometer onboard the Near Earth Asteroid Rendezvous spacecraft will measure gamma rays from the surface of 433 Eros in the 100-keV to 10-MeV energy region. Detection of characteristic gamma-ray emissions from such elements as O, Si, Fe, Ca, Ti, Mg, Al, H, K, Th, and U will allow the determination of abundances of these geologically important elements. Spatial resolution will be large, but the emission detected will originate from a volume of material down to depths of 10-20 cm below the surface. These measurements will make it possible to relate Eros to known meteorite classes and to relate these to geological processes on Eros. The calibration measurements and analysis procedures that are described will be needed for the reduction and analysis of gamma-ray data collected during the mission. In addition to geochemical measurements, the gamma-ray detector is used to detect gamma-ray bursts and forms part of the interplanetary network of gamma-ray detectors used to determine the source positions of gamma-ray bursts. [C] 2000 Academic Press Key Words: asteroids; instrumentation; gamma rays; geochemistry; NEAR mission.

Many tropical reef fisheries are underperforming relative to maximum sustained yields despite their importance for the economies and food security of natural resource dependent people. Assessments of fisheries in tropical reefs have been hampered by the logistic difficulty and costs of making empirical estimates of sustainable yields in multi-species fisheries. To overcome this limitation, we used empirical fish biomass recovery data in high-compliance closures to create a production curve estimate that established biomass and yields at maximum sustained yield (B msy). A multivariate machine learning model using environmental and human influence proxies made biomass and yield estimates in 10,815 ∼6.25 km2 Indian Ocean cells. Subsequent analyses determined the national over- and under-fishing status. Identified proxies of travel time from markets, depth, and fisheries management were the main drivers of biomass and subsequent status. The East African countries of Kenya, Tanzania, and Mozambique had 18,500 km2 of reef and the lowest regional estimated biomass - losing 17,600 tons of commercial target fish per year. Therefore, the estimated loss is between US$ 50–150 million per year depending on the worth in the fisheries trade's value chain The more populated islands of Reunion, Mauritius, Mayotte, and Comoros have smaller areas (5000 km2) and losing 3000 tons/year, and >US$ 9 million per year. Madagascar has many reefs (13,700 km2) and larger variation in yields with an estimated loss of ∼6000 tons/y. Increased restrictions could greatly increase the value of Indian Ocean fisheries by promoting the recovery of target biomass and recovering lost income. • A stock biomass and yield model created for 10,815 ∼6.25 km2 reef cells of the Indian Ocean. • Seven environmental variables were highly predictive of fish stock biomass. • Depth, travel time, fisheries restrictions, and governance were key manageable variables. • 55% of the 70,000 km2 of reef were losing 27,000 tons/year due to overfishing. • Estimated lost annual income was > 80–270 million US$ depending on value chain position. [ABSTRACT FROM AUTHOR]

Many political ecology debates hinge on the roles and outcomes of resource user regulation versus those arising from governance rules. Because of the difficulties of empirically testing theories of resource regulation, we evaluated the alternatives using a simulation modeling approach developed for East African coral reef fisheries where four scenarios of fisheries regulation on fish catch rates and resource ecology were evaluated. These scenarios were (1) a control simulation where fishing practices were held constant, (2) fishing that gradually incorporates fishers’ self-reported behavioral responses to declining resources, (3) rapid change where illegal gears were not allowed and effort was equally partitioned among the legal gears, and (4) gradual change where legal gears or exiting were adopted as yields decline. The model indicates that at moderate fishing effort (5 fishers/km 2 ), the gradual behavioral change scenarios two and four produced the highest per fisher yields and maintained the highest fish biomass compared to the other two strict-control options. At high fisher numbers (10 fishers/km 2 ), the rapid ban of illegal gear in scenario 3 had more similar ecological outcomes to gradual behavioral response scenarios 2 and 4. The model assumed no changes in behavior coming from outside the system or over longer periods of time that could potentially undermine or change the stated behavioral responses. The simulations show the difficulty of developing resource use regulations because of the complex interactions between numbers of fishers, behavioral responses, management decisions, and feedbacks to the resource. Nevertheless, the simulations indicate that at moderate fisher densities, governance strategies that allow resource users to respond to changing resources can produce better yield and resource outcomes than rigid control. Ecosystem models that do not incorporate fisher’s behavioral choices may overestimate their detrimental impacts. [ABSTRACT FROM AUTHOR]

Highlights: [•] We describe a process-based holistic coral reef ecosystem simulation model, CAFFEE. [•] CAFFEE links reef cover, production, metabolism, detritus, reef formation processes. [•] CAFFEE is validated with a 40 year time series of coral field data from Kenyan reefs. [•] We tested scenarios of reef responses to fisheries closures and bleaching events. [•] CAFFEE simulations successfully replicated general patterns seen in empirical data. [Copyright &y& Elsevier]

Abstract: Measuring the vulnerability of human populations to environmental change is increasingly being used to develop appropriate adaptation policies and management plans for different economic sectors. We developed a national-level vulnerability index that is specific to food security policies by measuring nations’ relative vulnerabilities to a decline in their coral reef fisheries. Coral reef fisheries are expected to decline with climate and anthropogenic disturbances, which may have significant consequences for food security. The vulnerability measure was composed of exposure, sensitivity, and adaptive capacity indicators specific to fisheries, reef management, and food security. The vulnerability index was used to evaluate 27 countries, as data required to fully populate the theoretical framework was limited. Of these, Indonesia and Liberia were identified as most and Malaysia and Sri Lanka as least vulnerable nations. Our analysis revealed two common national vulnerability characterizations: low income countries with low adaptive capacity and middle-income countries with higher adaptive capacity but high sensitivity. These results suggest developing context-specific policies and actions to build adaptive capacity in the low-income countries, and to decrease sensitivity in middle-income countries. Comparing our food security evaluation to a more general vulnerability approach shows that they produce different priority countries and associated policies. [Copyright &y& Elsevier]

Conservation and management policies rely on the perceived status of marine ecosystems, which are influenced by proxies and estimation methods. These include the number of protected areas, the percent coverage of nearshore areas, frequency or area relative to other ecosystems, and a diverse set of possible but often poorly evaluated impacts. Based on the emerging studies of the geographic distribution of reef fish biomass, I used two metrics of travel time to human settlements (>4-h) and major markets (>9-h) to estimate the percentage of passive conservation as remote wilderness in 99 tropical ecoregions. Randomly selecting >25,000 tropical coral reefs from a current coral reef map, 2.5% of the random reefs were classified as active conservation or high compliance marine reserves. Passive conservation was considerably larger at ~12% using the >4-h and 48% by the >9-h travel time thresholds. Marine reserves were more frequently located >4-h than <4-h travel times, indicating their inadequate usage as fisheries management tools. Therefore, travel distance or passive conservation and possibly fishing restrictions are the main mechanisms protecting coral reefs. Evaluating the distribution of an active plus passive conservation threshold of 30% protection indicated that 35% of the ecoregions did not achieve this level while 15% had a 100% deficit. When human dependency on fisheries was evaluated, most of Africa, Asia, and Caribbean ecoregions lacked significant refuge and therefore vulnerable to fisheries collapses. Estimates of passive plus active conservation deficits provides a path to prioritize actions to increase active conservation and restricting human and market demands. • Reef status evaluated using high resolution maps and random sampling. • Most reef conservation achieved through travel and fisheries restrictions. • High compliance closures ~2.5% of randomly selected reefs. • The ratio of remote reefs to human dependence is highly variable. • Passive plus active conservation deficits a priority for policy actions. [ABSTRACT FROM AUTHOR]

There is a need to develop methods and a decision support system to establish marine protected areas that harbour coral reefs that are resilient to climate change. This requires understanding patterns of coral''s susceptibility to thermal stress and how coral communities will change with the environmental variables associated with climate change. This study combined surface currents, wind velocity, sea surface temperature (SST), UV radiation, photosynthetically active radiation (PAR), and chlorophyll-a concentration for the western Indian Ocean and known relationships with coral bleaching and mortality to derive predictor variables that correlate with thermal stress. SST variability, UV, maximum temperature and wind speed had the highest influence on susceptibility estimates. Two susceptibility models were developed using Spatial Principal Component Analysis (SPCA) and cosine amplitude-AHP methods and a fuzzy logic technique for integrating environmental variables into a measure of susceptibility. Susceptibility models identified regional gradients in environmental stress, with the north-western Indian Ocean and some central Indian Ocean Islands as high and the southern African coastline and islands east of Madagascar as low vulnerability regions. Half of the strictly no take zones in the region are situated in locations with medium to high susceptibility. Future studies using high-resolution data can better estimate the vulnerability of specific locations and the establishment of marine protected areas where coral reef diversity is more likely to persist through climate change. [Copyright &y& Elsevier]

Abstract Analysis of Lunar Exploration Neutron Detector (LEND) neutron count rates for a large set of mid-latitude craters provides evidence for lower hydrogen content in the crater interiors compared to typical highland values. Epithermal neutron count rates for crater interiors measured by the LEND Sensor for Epithermal Neutrons (SETN) were compared to crater exteriors for 301 craters and displayed an increase in mean count rate at the ∼9-σ confidence level, consistent with a lower hydrogen content. A smaller subset of 31 craters also shows a significant increase in Optical Maturity parameter implying an immature regolith. The increase in SETN count rate for these craters is greater than the increase for the full set of craters by more than a factor of two. Highlights • SETN count rates for a large set of mid-latitude craters provides evidence for lower hydrogen content in crater interiors. • Increase in mean count rate for 301 craters is significant at the ∼9-σ confidence level, implying lower hydrogen content. • A smaller subset of 31 craters also shows a significant increase in OMAT implying an immature regolith. • The increase in count rate for the 31 craters is greater than the increase for the full set of craters by a factor of ∼2. [ABSTRACT FROM AUTHOR]