Reef fish communities were assessed using visual census techniques across 100 reefs spanning over... more Reef fish communities were assessed using visual census techniques across 100 reefs spanning over 2.000 km of coastline. Each reef was considered a sample unit and species densities per 100 m² was used for calculating true diversity measures. Diversity patterns were investigated using "true diversity" measures (sensu Jost 2006), considering the effective number of species equal to Hill numbers (qD). Values in dataset correspond to number of effective species per reef (α diversity, Dα), for q = 0, 1 and 2, using sampled area as weights. Each line represents a reef, labeled by a Code, followed by Brazilian State, Location name, Latitude, Longitude and Source of the species data. Predictors used for adjusting GLMs are presented next: Reef morphotype (categorical predictor), with five levels corresponding to Brazilian reef morphological structures (cemented terraces, fringing, patch, bank and pinnacle reefs, see Appendix S1 for a detailed description). Depth, as the average depth of the reef in meters, measured in situ, isolation, as the linear distance between the reef to the nearest point in mainland, are also presented.
Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching an... more Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef surveys during 2014-2017 revealed that 80% of surveyed reefs experienced significant coral bleaching and 35% experienced significant coral mortality. The global extent of significant coral bleaching and mortality was assessed by extrapolating results from reef surveys using comprehensive remote-sensing data of regional heat stress. This model predicted that 51% of the world’s coral reefs suffered significant bleaching and 15% significant mortality, surpassing damage from any prior global bleaching event. These observations demonstrate that global warming’s widespread damage to coral reefs is accelerating and underscores the threat anthropo...
Intertidal environments are boundaries between marine and terrestrial ecosystems that are subject... more Intertidal environments are boundaries between marine and terrestrial ecosystems that are subject to rapid fluctuations across tidal cycles. This study investigates, for the first time, the photobiology of symbiotic zoanthids inhabiting different tidal environments: subtidal, intertidal pools and intertidal areas exposed to air during low tide. More specifically, we assessed the photochemical efficiency, Symbiodinium density and photosynthetic pigments profile of Zoanthus sociatus during low tide. Photochemical efficiency was lower and cell density higher in air exposed zoanthids. The profile of photosynthetic pigments also varied significantly among tidal habitats, particularly photoprotective pigments such as dinoxanthin and diadinoxanthin. Differences were also observed for the pigment content per cell, but the proportion of particular pigments (peridinin/chlorophyll-a and diatoxanthin+diadinoxanthin/chlorophyll-a) remained stable. Results suggest that aerial exposure conditions ...
An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (O... more An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (OA) during the Brazilian OA Network/Surface Ocean-Lower Atmosphere Study (BrOA/SOLAS) Workshop. Fifteen members of the BrOA Network ( www.broa.furg.br ) authored this review. The group concluded that identifying and evaluating the regional effects of OA is impossible without understanding the natural variability of seawater carbonate systems in marine ecosystems through a series of long-term observations. Here, we show that the western South Atlantic Ocean (WSAO) lacks appropriate observations for determining regional OA effects, including the effects of OA on key sensitive Brazilian ecosystems in this area. The impacts of OA likely affect marine life in coastal and oceanic ecosystems, with further social and economic consequences for Brazil and neighboring countries. Thus, we present (i) the diversity of coastal and open ocean ecosystems in the WSAO and emphasize their roles in the marin...
Abstract Climate change and other types of environmental stress are known to increase corals’ vul... more Abstract Climate change and other types of environmental stress are known to increase corals’ vulnerability to bleaching, a process whereby colonies lose their colour either due to the loss of photosynthetic symbionts or their pigments. Although bleaching leaves the coral skeleton visible under its transparent tissue, not all white coral colonies display this feature. This raises the question as to whether all ‘white’-shaded colonies are indeed bleached. Within this context, Montastraea cavernosa colonies of different colour types (dark brown, light brown, bleached and white) were sampled for photobiological evaluation. Here, we show that, while the conventional spectral reflectance techniques failed to discriminate white from bleached colonies, chlorophyll fluorescence, photosynthetic pigment profile and Symbiodinium density enabled a clear distinction between these shades. Subsequently, video transects from reef monitoring surveys at Todos os Santos Bay (Brazil) revealed that the proportion of bleached and white colonies is similar, thus suggesting that current coral reef surveys may be overestimating the bleaching of M. cavernosa by nearly twofold.
Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the ca... more Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the causes, effects and consequences of phase shifts on reef fish communities have only been considered for coral-to-macroalgae shifts. Therefore, there is a large information gap regarding the consequences of novel phase shifts and how these kinds of phase shifts impact on fish assemblages. This study aimed to compare the fish assemblages on reefs under normal conditions (relatively high cover of corals) to those which have shifted to a dominance of the zoantharian Palythoa cf. variabilis on coral reefs in Todos os Santos Bay (TSB), Brazilian eastern coast. We examined eight reefs, where we estimated cover of corals and P. cf. variabilis and coral reef fish richness, abundance and body size. Fish richness differed significantly between normal reefs (48 species) and phase-shift reefs (38 species), a 20% reduction in species. However there was no difference in fish abundance between normal and ...
Extensive degradation of coral reefs makes it imperative to create functional models that demonst... more Extensive degradation of coral reefs makes it imperative to create functional models that demonstrate ecological processes which occur in alternative states that persist over time. These models provide important information that can help in decision making regarding management measures for both the prevention of further degradation and the recovery of these ecosystems. Development of these models requires identifying and testing the ecological processes that will impose the reduction of coral cover and, preferably, identifying the disturbance that triggers this phenomenon. For this reason, research programs are a useful tool which allows a focus on the production of information for modeling. It should start with survey investigations and tests of hypotheses concerning the cause of the reduction of coral cover. Subsequently, projects should be guided by the most probable hypotheses, focusing on one guild or functional group at a time until the "trigger" process which unleashed the disturbance is identified. Even if incomplete, these models already provide information for focusing management steps.
Rodríguez-Ramírez, A., Bastidas, C., Rodríguez, S., Leão, Z., Kikuchi, R., Oliveira, M., Gil, D.,... more Rodríguez-Ramírez, A., Bastidas, C., Rodríguez, S., Leão, Z., Kikuchi, R., Oliveira, M., Gil, D., Garzón-Ferreira, J., Reyes-Nivia, MC, Navas-Camacho, R., Santodomingo, N., Diaz-Pulido, G., Venera-Ponton, D., Florez-Leiva, L., Rangel-Campo, A., Orozco, C., Márquez, JCZS, López-Victoria, M., Sánchez, JA and Hurtado, MC (2008). The Effects of Coral Bleaching in Southern Tropical America: Brazil, Colombia, and Venezuela. In C. Wilkinson and D. Souter (Ed.), Status of Caribbean Coral Reefs after Bleaching and Hurricanes in 2005 (pp. 105-114) ...
Brazilian reefs comprise the largest and the richest reefs of the Southwestern Atlantic Ocean. In... more Brazilian reefs comprise the largest and the richest reefs of the Southwestern Atlantic Ocean. Indicators of reef vitality reveal that reefs located less than 5 km from the coastline, the inshore reefs, are in poorer conditions than those located more than 5 km off the coast, the offshore reefs. The inshore reefs are the most impacted by the effects of eutrophic waters associated with sewage pollution, high sedimentation rates and water turbidity, and the most exposed to the effects of bleaching and infectious diseases. From 1998 to 2005, long-term sea water thermal anomaly events, equal or higher than 1oC, were responsible for more than 30% of bleached corals in the inshore reefs. In the offshore reefs of the Abrolhos area, bleaching was milder, but the reefs are strongly threatened by the incidence of diseases that have escalated in prevalence from negligible to alarmingly high levels in recent years. Although bleaching and coral disease have not yet caused mass mortality in the B...
Todos os Santos Bay is a Brazilian Environmental Protection Area equivalent to Category V of the ... more Todos os Santos Bay is a Brazilian Environmental Protection Area equivalent to Category V of the International Union for Conservation of Nature, which encloses two groups of coral reefs in the region of the greatest biodiversity in the Western South Atlantic Ocean, the coast of the state of Bahia. This type of Protected Area aims the sustainable use of the natural resources and the biodiversity conservation. The Todos os Santos Bay Environmental Protection Area does not have a management plan, yet, that is a tool for restricting the use of natural resources in order to promote conservation of the environment. In Todos os Santos Bay there are two regions of reefs with different hydrodynamic regimes and human impacts: the reefs located at the entrance of the bay, the outside reefs, which are directly exposed to the wave’s action, and the largest group of reefs that is located inside the bay in a lower hydrodynamic regime. These later reefs are located near Salvador, a city with 2.8 mi...
Reef fish communities were assessed using visual census techniques across 100 reefs spanning over... more Reef fish communities were assessed using visual census techniques across 100 reefs spanning over 2.000 km of coastline. Each reef was considered a sample unit and species densities per 100 m² was used for calculating true diversity measures. Diversity patterns were investigated using "true diversity" measures (sensu Jost 2006), considering the effective number of species equal to Hill numbers (qD). Values in dataset correspond to number of effective species per reef (α diversity, Dα), for q = 0, 1 and 2, using sampled area as weights. Each line represents a reef, labeled by a Code, followed by Brazilian State, Location name, Latitude, Longitude and Source of the species data. Predictors used for adjusting GLMs are presented next: Reef morphotype (categorical predictor), with five levels corresponding to Brazilian reef morphological structures (cemented terraces, fringing, patch, bank and pinnacle reefs, see Appendix S1 for a detailed description). Depth, as the average depth of the reef in meters, measured in situ, isolation, as the linear distance between the reef to the nearest point in mainland, are also presented.
Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching an... more Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef surveys during 2014-2017 revealed that 80% of surveyed reefs experienced significant coral bleaching and 35% experienced significant coral mortality. The global extent of significant coral bleaching and mortality was assessed by extrapolating results from reef surveys using comprehensive remote-sensing data of regional heat stress. This model predicted that 51% of the world’s coral reefs suffered significant bleaching and 15% significant mortality, surpassing damage from any prior global bleaching event. These observations demonstrate that global warming’s widespread damage to coral reefs is accelerating and underscores the threat anthropo...
Intertidal environments are boundaries between marine and terrestrial ecosystems that are subject... more Intertidal environments are boundaries between marine and terrestrial ecosystems that are subject to rapid fluctuations across tidal cycles. This study investigates, for the first time, the photobiology of symbiotic zoanthids inhabiting different tidal environments: subtidal, intertidal pools and intertidal areas exposed to air during low tide. More specifically, we assessed the photochemical efficiency, Symbiodinium density and photosynthetic pigments profile of Zoanthus sociatus during low tide. Photochemical efficiency was lower and cell density higher in air exposed zoanthids. The profile of photosynthetic pigments also varied significantly among tidal habitats, particularly photoprotective pigments such as dinoxanthin and diadinoxanthin. Differences were also observed for the pigment content per cell, but the proportion of particular pigments (peridinin/chlorophyll-a and diatoxanthin+diadinoxanthin/chlorophyll-a) remained stable. Results suggest that aerial exposure conditions ...
An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (O... more An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (OA) during the Brazilian OA Network/Surface Ocean-Lower Atmosphere Study (BrOA/SOLAS) Workshop. Fifteen members of the BrOA Network ( www.broa.furg.br ) authored this review. The group concluded that identifying and evaluating the regional effects of OA is impossible without understanding the natural variability of seawater carbonate systems in marine ecosystems through a series of long-term observations. Here, we show that the western South Atlantic Ocean (WSAO) lacks appropriate observations for determining regional OA effects, including the effects of OA on key sensitive Brazilian ecosystems in this area. The impacts of OA likely affect marine life in coastal and oceanic ecosystems, with further social and economic consequences for Brazil and neighboring countries. Thus, we present (i) the diversity of coastal and open ocean ecosystems in the WSAO and emphasize their roles in the marin...
Abstract Climate change and other types of environmental stress are known to increase corals’ vul... more Abstract Climate change and other types of environmental stress are known to increase corals’ vulnerability to bleaching, a process whereby colonies lose their colour either due to the loss of photosynthetic symbionts or their pigments. Although bleaching leaves the coral skeleton visible under its transparent tissue, not all white coral colonies display this feature. This raises the question as to whether all ‘white’-shaded colonies are indeed bleached. Within this context, Montastraea cavernosa colonies of different colour types (dark brown, light brown, bleached and white) were sampled for photobiological evaluation. Here, we show that, while the conventional spectral reflectance techniques failed to discriminate white from bleached colonies, chlorophyll fluorescence, photosynthetic pigment profile and Symbiodinium density enabled a clear distinction between these shades. Subsequently, video transects from reef monitoring surveys at Todos os Santos Bay (Brazil) revealed that the proportion of bleached and white colonies is similar, thus suggesting that current coral reef surveys may be overestimating the bleaching of M. cavernosa by nearly twofold.
Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the ca... more Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the causes, effects and consequences of phase shifts on reef fish communities have only been considered for coral-to-macroalgae shifts. Therefore, there is a large information gap regarding the consequences of novel phase shifts and how these kinds of phase shifts impact on fish assemblages. This study aimed to compare the fish assemblages on reefs under normal conditions (relatively high cover of corals) to those which have shifted to a dominance of the zoantharian Palythoa cf. variabilis on coral reefs in Todos os Santos Bay (TSB), Brazilian eastern coast. We examined eight reefs, where we estimated cover of corals and P. cf. variabilis and coral reef fish richness, abundance and body size. Fish richness differed significantly between normal reefs (48 species) and phase-shift reefs (38 species), a 20% reduction in species. However there was no difference in fish abundance between normal and ...
Extensive degradation of coral reefs makes it imperative to create functional models that demonst... more Extensive degradation of coral reefs makes it imperative to create functional models that demonstrate ecological processes which occur in alternative states that persist over time. These models provide important information that can help in decision making regarding management measures for both the prevention of further degradation and the recovery of these ecosystems. Development of these models requires identifying and testing the ecological processes that will impose the reduction of coral cover and, preferably, identifying the disturbance that triggers this phenomenon. For this reason, research programs are a useful tool which allows a focus on the production of information for modeling. It should start with survey investigations and tests of hypotheses concerning the cause of the reduction of coral cover. Subsequently, projects should be guided by the most probable hypotheses, focusing on one guild or functional group at a time until the "trigger" process which unleashed the disturbance is identified. Even if incomplete, these models already provide information for focusing management steps.
Rodríguez-Ramírez, A., Bastidas, C., Rodríguez, S., Leão, Z., Kikuchi, R., Oliveira, M., Gil, D.,... more Rodríguez-Ramírez, A., Bastidas, C., Rodríguez, S., Leão, Z., Kikuchi, R., Oliveira, M., Gil, D., Garzón-Ferreira, J., Reyes-Nivia, MC, Navas-Camacho, R., Santodomingo, N., Diaz-Pulido, G., Venera-Ponton, D., Florez-Leiva, L., Rangel-Campo, A., Orozco, C., Márquez, JCZS, López-Victoria, M., Sánchez, JA and Hurtado, MC (2008). The Effects of Coral Bleaching in Southern Tropical America: Brazil, Colombia, and Venezuela. In C. Wilkinson and D. Souter (Ed.), Status of Caribbean Coral Reefs after Bleaching and Hurricanes in 2005 (pp. 105-114) ...
Brazilian reefs comprise the largest and the richest reefs of the Southwestern Atlantic Ocean. In... more Brazilian reefs comprise the largest and the richest reefs of the Southwestern Atlantic Ocean. Indicators of reef vitality reveal that reefs located less than 5 km from the coastline, the inshore reefs, are in poorer conditions than those located more than 5 km off the coast, the offshore reefs. The inshore reefs are the most impacted by the effects of eutrophic waters associated with sewage pollution, high sedimentation rates and water turbidity, and the most exposed to the effects of bleaching and infectious diseases. From 1998 to 2005, long-term sea water thermal anomaly events, equal or higher than 1oC, were responsible for more than 30% of bleached corals in the inshore reefs. In the offshore reefs of the Abrolhos area, bleaching was milder, but the reefs are strongly threatened by the incidence of diseases that have escalated in prevalence from negligible to alarmingly high levels in recent years. Although bleaching and coral disease have not yet caused mass mortality in the B...
Todos os Santos Bay is a Brazilian Environmental Protection Area equivalent to Category V of the ... more Todos os Santos Bay is a Brazilian Environmental Protection Area equivalent to Category V of the International Union for Conservation of Nature, which encloses two groups of coral reefs in the region of the greatest biodiversity in the Western South Atlantic Ocean, the coast of the state of Bahia. This type of Protected Area aims the sustainable use of the natural resources and the biodiversity conservation. The Todos os Santos Bay Environmental Protection Area does not have a management plan, yet, that is a tool for restricting the use of natural resources in order to promote conservation of the environment. In Todos os Santos Bay there are two regions of reefs with different hydrodynamic regimes and human impacts: the reefs located at the entrance of the bay, the outside reefs, which are directly exposed to the wave’s action, and the largest group of reefs that is located inside the bay in a lower hydrodynamic regime. These later reefs are located near Salvador, a city with 2.8 mi...
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