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Identifying relatively intact areas within ecosystems, and determining the conditions favoring their existence, is necessary for effective management in the context of widespread environmental degradation. In this study, we used 3,766 surveys of randomly selected sites in the United States and U.S. Territories to identify the correlates of sites categorized as ‘oases’ (defined as sites with relatively high total coral cover). We used occupancy models to evaluate the influence of ten environmental predictors on the probability that an area (21.2 km2 cell) would harbor coral oases defined at four spatial extents: cross-basin, basin, region, and sub-region. Across all four spatial extents, oases were more likely to occur in habitats with high light attenuation. The influence of the other environmental predictors on the probability of oasis occurrence were less consistent and varied with the scale of observation. Oases were most likely in areas of low human population density, but this effect was evident only at the cross-basin and sub-regional extents. At the regional and sub-regional extents oases were more likely where sea-surface temperature was more variable, whereas at the larger spatial extents the opposite was true. By identifying the correlates of oasis occurrence, the model can inform the prioritization of reef areas for management. Areas with biophysical conditions that confer corals with physiological resilience, as well as limited human impacts, likely support coral reef oases across spatial extents. Our approach is widely applicable to the development of conservation strategies to protect biodiversity and ecosystems in an era of magnified human disturbance.

Methodology and Discussion - Table 1(SADIE outputs, describing the indices for evaluating the spatial distribution of each observed SymbiodiniumITS2 type), Table 2(Cluster indices generated by SADIE analysis for symbionts at each site), Table 3(Summary of DISTLM population-scale outputs), Table 4 (Genotype data for the coral host, Orbicella annularis, by site.)

Reef managers cannot fight global warming through mitigation at local scale, but they can use information on thermal patterns to plan for reserve networks that maximize the probability of persistence of their reef system. Here we assess previous methods for the design of reserves for climate change and present a new approach to prioritize areas for conservation that leverages the most desirable properties of previous approaches. The new method moves the science of reserve design for climate change a step forwards by: (1) recognizing the role of seasonal acclimation in increasing the limits of environmental tolerance of corals and ameliorating the bleaching response; (2) using the best proxy for acclimatization currently available; (3) including information from several bleaching events, which frequency is likely to increase in the future; (4) assessing relevant variability at country scales, where most management plans are carried out. We demonstrate the method in Honduras, where a reassessment of the marine spatial plan is in progress.

En Venezuela, los estudios del bentos marino se han concentrado en zonas costeras someras. La presente investigación ha permitido conocer y cuantificar, por vez primera, la macrofauna bentónica de aguas profundas, ubicadas en la zona noreste del Delta del Orinoco. Muestras de sedimento fueron tomadas con el empleo de una draga tipo box-core (0,25m² de área) en 81 estaciones comprendidas entre los 50 y 1500m de profundidad. Se colectaron 1673 organismos pertenecientes a 11 phyla, siendo los anélidos los más abundantes (63,56%) y de ellos los poliquetos representaron el 60,73%. Siguen en abundancia los crustáceos (15,42%), nemátodos (9,26%) y bivalvos (7,11%). El 70,47% de la fauna fue retenido en el tamiz de 0,5mm de apertura de malla. En general, esta comunidad bentónica se caracterizó por una elevada diversidad biológica, pero con una muy baja densidad de organismos (20,65 ±25,87ind/estación). Los mayores valores promedio (129 individuos) se obtuvieron en la zona somera de la plataforma, entre 0-200m, mientras que los valores más bajos se registraron a grandes profundidades (0-37 individuos). The studies on marine benthos performed in Venezuela have concentrated on shallow coastal waters. The present study was focalized in the identification and quantification, for the first time, of the benthic macrofauna of deep waters. The study area is located at the Atlantic coast, northeast from the Orinoco River delta coast-line. Sediment samples were collected by means of a box-core type grab (0.25m² area) in a total of 81 stations, which ranged 50-1500m deep. A total of 1673 individuals were collected, representing 11 phyla, with annelids as the most abundant (63.56%). Within this group, polychaetes represented 60.73%. Thereafter, crustaceans (15.42%), nematodes (9.26%) and bivalves (7.11%) represented the other main groups. Most of the fauna (70.49%) was retained in the 0.5mm sieve. The benthic community was characterized by a high biodiversity, but with a very low density (20.65 ±25.87ind/station). The greatest mean abundance (129 individuals) was found in the shallow zones, at 0-200m depth and the lowest value was recoded at greater depths (0-37 individuals). Na Venezuela, os estudos do Bentos Marinho têm se concentrado em zonas costeiras rasas. A presente investigação tem permitido conhecer e quantificar, por primeira vez, a macro fauna bentônica de águas profundas, localizadas na zona nordeste do Delta do rio Orinoco. Amostras de sedimento foram tomadas mediante o uso de uma draga tipo box-core (0,25m2 de área) em 81 estações compreendidas entre os 50 e 1.500m de profundidade. Recolheram-se 1.673 organismos pertencentes a 11 phyla, sendo os anelídeos os mais abundantes (63,56%) e deles os poliquetos representaram 60,73%. Seguem em abundância os crustáceos (15,42%), nematódeos (9,26%) e bivalves (7,11%). 70,47% da fauna foi retida no tamis de 0,5mm de abertura de malha. Em geral, esta comunidade bentônica se caracterizou por uma elevada diversidade biológica, mas com uma muito baixa densidade de organismos (20,65 ±25,87ind/estação). Os maiores valores médios (0-129 indivíduos) se obtiveram na zona rasa da plataforma, entre 0-200m, enquanto que os valores mais baixos se registraram a grandes profundidades (0-37 indivíduos).