Tropical landscape and seascape systems are intimately linked by complex ecological relationships... more Tropical landscape and seascape systems are intimately linked by complex ecological relationships that provide environmental services to human societies located in coastal areas and beyond. Paradoxically, nonsustainable activities from these human societies are threatening the functions and benefits of these systems. Anthropogenic processes that damage tropical seascapes are rapidly increasing as a result of coastal and tourism development, increasing human population, unsustainable economic growth, and extensive transformations of natural landscapes. In addition to this overwhelming trend, tropical coastal seascapes are threatened by global climate change. Thus, to address this problem, it is essential to understand the complex ecological relationships between the components of coastal seascape systems and their links to land ecosystems, including the positive and negative effects of humans. The physical and ecological relationships between tropical landscapes and seascapes often define the energy and matter fluxes through which human activities exert their influence on coastal ecosystems. We illustrate these relationships by presenting a case study and conceptual model of coastal and tourism development in the Yucatan Peninsula, Mexico. Scientific knowledge and proposals for better governance practices are available to guide management actions and to protect the connectivity of seascape systems. Nonetheless, political will, coupled with the implementation of local and regional integrated management schemes of coastal zones, is urgent. More examples are needed of inland and coastal human societies that successfully integrate scientific knowledge of the links among ecosystems and their decision-making processes in order to achieve sustainable development based on the services provided by their surrounding seascapes.
As the impact of anthropogenic activity and climate change continue to accelerate rates of degrad... more As the impact of anthropogenic activity and climate change continue to accelerate rates of degradation on Caribbean coral reefs, conservation and restoration faces greater challenges. At this stage, it is of particular importance in coral reefs to recognize and to understand the structural spatial patterns of benthic assemblages. We developed a field-based framework of a Caribbean reefscape benthic structure by using hermatypic corals as an indicator group of global biodiversity and bio-construction patterns in 11 reefs of the northern sector of the mesoamerican barrier reef system (nsMBRS). Four hundred and seventy four video-transects (50 m long by 0.4 m wide) were performed throughout a gradient of reef complexity from north to south (∼400 km) to identify coral species, families and ensembles of corals. Composition and abundance of species, families and ensembles showed differences among reefs. In the northern zone, the reefs had shallow, partial reef developments with low diversities, dominated by Acropora palmata, Siderastrea spp., Pseudodiploria strigosa, and Agaricia tenuifolia. In the central and southern zones, reefs presented extensive developments, high habitat heterogeneity, and the greatest diversity and dominance of Orbicella annularis and Orbicella faveolata. These two species determined the structure and diversity of corals in the central and southern zones of the nsMBRS and their bio-construction in these zones is unique in the Caribbean. Their abundance and distribution depended on the reef habitat area, topographic complexity and species richness. Orbicella species complex were crucial for maintaining the biodiversity and bio-construction of the central and southern zones while A. palmata in the northern zones of the nsMBRS.
ABSTRACT Global climate change and local anthropogenic pressures are among the primary factors le... more ABSTRACT Global climate change and local anthropogenic pressures are among the primary factors leading to the decline of functional biodiversity and critical habitats in coral reefs. Coral bleaching, the potential decreases in dissolved oxygen concentration (deoxygenation) and pH (acidification) in the oceans can induce severe changes in coral reef ecosystem biodiversity and functionality. The main objective of this study was to apply four Ecopath with Ecosim models of a Caribbean coral reef system to individually and collectively model the effects of coral bleaching on the trophic web, deoxygenation on fish, and acidification on calcifying organisms. These three sources of stress were used as forcing functions on several trophic groups depending on the model. The forcing functions were scaled according to the species’ responses achieved in previously tested climate change marine models. For the bleaching model, a mediation function was also considered that represents the degree of coral reef protection on small and intermediate fish groups. The dynamic models were constructed from an extensive database of 171 reef fish species (abundance and biomass) and benthic communities from 13 coral reefs that were evenly distributed parallel to approximately 400 km of the Mexican Caribbean coast as well as fishery landings in this area. Simulations driven with these different forcing and mediation functions predicted different changes in the biomasses of fish and non-fish functional groups as well as the biomass of the functional groups of fished species. Coral bleaching and pH reduction caused a phase shift to a decrease in coral biomass and an increase in primary producer biomass. This shift produced a cascading decrease in the biomass of small and intermediate fish groups. Additionally, the fished functional group biomass increased with coral bleaching but decreased with the effects of decreased oxygen on fish and pH on calcifying organisms. The biomasses of certain macroinvertebrate functional groups were predicted to respond favourably to the combined effect of the sources of stress. However, when all the sources of stress were combined, we found a general decrease of biomass in fish, non-fish, and some commercially valuable fish and macroinvertebrate functional groups, suggesting that the combined effects of stress induced synergistic effects as a result of global climate change and overfishing, which can result in a potential loss of biodiversity and ecosystem services in coral reefs.
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory...
... 3 Laboratorio de Ecosistemas Marinos y Acuicultura (LEMA), Departamento de Ecología, CUCBA, U... more ... 3 Laboratorio de Ecosistemas Marinos y Acuicultura (LEMA), Departamento de Ecología, CUCBA, Universidad de Guadalajara, Carretera Guadalajara–Nogales Km 15.5, AP ... en influir sobre la composición local de las especies y la diversidad en peces y corales: (a) el área del ...
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (
The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious imp... more The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious impacts on coral reef food-webs. We have used an Ecopath-with-Ecosim model to predict the impacts of lionfish invasion on a coral reef community based on pre-invasion fish community data. Forty-six groups were defined, and an initial Ecopath model was balanced with a near-zero biomass of lionfish. In Ecosim, the near-zero biomass was eradicated by applying a very high fishing pressure in the first year of simulation. We subsequently (re-)introduced lionfish with a very low biomass, and allowed them to increase to very high abundance. With a near-zero lionfish biomass, the great majority of mesocarnivorous/omnivorous coral reef fish were predicted to be dominant while sharks were predicted to be the apex predators. Different management scenarios were established in the ecosystem to explore the eradication and resilience of lionfish. The management scenarios showed that if all adult lionfish were exploitable it will in theory be possible to fish the lionfish to a very low level, but the fishing pressure will have to be maintained, or the lionfish will recover. If the largest individuals are unexploitable it will be much more difficult to control the lionfish population.
The structural patterns and trophodynamics of the different fish species in the reef complex of P... more The structural patterns and trophodynamics of the different fish species in the reef complex of Palancar-Chunchakaab, located in the South of Cozumel Island, Mexican Caribbean, were studied. A total of 166 species were identified for the whole reef complex. The analysis of 19,636 recorded and 2291 fish collected allowed the populations to be characterized in terms of diversity, distribution, abundance, dominant species and habitat-fish interactions. Using these parameters, three well defined reef-fish communities were described in relation to three zones: (1) Thalassia zone (THZ), (2) Lagoon (LA) and (3) Shelf-Edge Reef (SER). These communities included 64 species (39% of the total number) that were restricted to a single zone,. The remaining 61% consisted of migratory species that interacted between the defined zones (interdependence of habitat): (1) THZ-LA, (2) THZ-LA-SER, and (3) LA-SER. Diversity was highest in the rainy season in SER (H′ n = 3.3). Analysis of distribution and frequency of 42 of the recorded species revealed that for 25%, life cycle and THZ-SER were closely related. The remaining 75% were more associated with SER or THZ and they used these habitats for feeding, breeding and/or protection. In THZ, > 70% of the total number of species were juveniles; in LA, 40% were preadults-adults; and in SER 80% were adults. The obvious interdependence between habitats suggested a distinct use of the resources by means of migration patterns. By decreasing the order of importance, the major diet types can be ranked as follows: (1) type I carnivores, mainly active by day, preying on small organisms such as crustaceans, polychaetes, mollusks, echinoderms; (2) type II carnivores, nocturnal species consuming larger crustaceans and fish; (3) strict piscivores species; (4) herbivores species; (5) planktivores species; (6) omnivores species; and (7) sessile invertebrate browsers. With the exception of SER, 14%–44% of the type II invertebrate feeders were restricted to the three defined habitats. Of the migratory species, the large invertebrate feeders were the dominant group (21%–41%). The present study suggests that the variation of species diversity patterns and trophic structure are associated with sequential habitat use according to the life cycle. This type of study allowed us to compare the diversity and trophic community of reef fish of the same system and to recognize the energetic interdependence that exists between the habitats.
Journal of Experimental Marine Biology and Ecology, 2008
This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory variables for the observed biogeographic patterns of fish and coral biodiversity than they were singly. Coral and fish species richness were strongly correlated. Indicators of functional diversity (fish trophic groups and coral morphofunctional groups) followed the same biogeographic patterns as species richness. Reefscape attributes (RA, LCC, and HC) were shown to be good proxies for critical coral reef biodiversity values. This means that simple reefscape attributes can be used to predict more complex biodiversity values of different reef areas. Such predictions can provide an invaluable guide for regional biodiversity assessments, the extrapolation of these results to unsurveyed areas, and guidance for ecoregionalization within large reef tracts where data are sparse.
A comparison was made using general trophic models of three coral reef slopes in the Mexican Cari... more A comparison was made using general trophic models of three coral reef slopes in the Mexican Caribbean. Two reef slopes are in semi-protected areas (Boca Paila, Tampalam) and the third is subject to more intense exploitation (Mahahual). The mass-balanced models of the three reef slopes were derived from fish biomass density data obtained directly from field measurements (fish census). Other trophic groups were derived from published sources. Initial parameters for the three reef slopes were calculated using the Ecopath with Ecosim software. Comparisons of model outputs were done to establish differences between reef slope systems that are semi-protected and unprotected from fishing activities. The most significant results include: partition of production was always lowest for the unprotected reef slope; net primary production was three times higher for the semi-protected slopes than for the unprotected one; total catch in the unprotected reef slope was three and eight times higher than the two semi-protected reef slopes; food chain length increased as total catch increased; the calculated trophic level of the catch was relatively lower in the unprotected reef slope; and catch per net primary production (gross efficiency) was higher in the unprotected reef slope than the semi-protected reef slopes. It is concluded that trophic macrodescriptors can serve as a guide to the hard-to-detect negative effects of coral reef management, aid in decision-making, and emphasize the effects that structural descriptors, (e.g. total fish biomass, diversity indices) do not detect.
In 1999 Montastraea faveolata and M. annularis were the most numerous "large" (≥25 cm diameter) s... more In 1999 Montastraea faveolata and M. annularis were the most numerous "large" (≥25 cm diameter) stony corals at ~10 m on fore reefs in the central and southern areas, respectively, of Quintana Roo, México. Reductions in live stony coral cover (from ~25% to ~12% in <10 years) and high recent partial-colony mortality (7-27.5%) are indications of declining reef conditions. Diseases in the five more northerly reefs, as well as tissue loss from the 1998 El Nino Southern Oscillation (ENSO) bleaching event and/or from on-going bleaching during June-July 1999 in the three southernmost reefs, appeared responsible for much of the recent mortality. Although turf algae predominated everywhere, macroalgae were relatively more abundant in the five more northerly reefs (four of which are in a reserve where herbivorous fishes currently are less numerous than further south). Additional perturbations associated with tourism development in the southern area could result in a loss of resilience of these coastal reefs.
Increases of fishing and tourism threaten the natural relationships between reef fish communities... more Increases of fishing and tourism threaten the natural relationships between reef fish communities and their environments. All species of reef fishes were visually assessed in the central and southern Mexican Caribbean in eight fringing reefs, four of which are in a protected biosphere reserve. The sampling design included three spatial scales from tens of meters to tens of kilometers. A total of 9,908 individuals belonging to 128 species and 43 families were identified in 144 belt transects. Zooplankton feeders were the most important trophic group by number of individuals; plant and detritus feeders dominated by number of species. Herbivores were larger in unprotected reefs than in the reserve. Regression analyses showed significant inverse relationships between total fish species density and macroalgal index (a proxy for macroalgal biomass) and, for "large" (≥25 cm diameter) stony corals, partial-colony mortality and live/dead ratio. Significant inverse relationships were also found between mean abundance of the plant and detritus feeders guild and macroalgal index and macroalgae abundance. Geomorphological factors and anthropogenic impacts, both positive (protection) in the reserve and negative (fishing and tourism) in unprotected areas, may explain these spatial patterns in reef-fish community structure.
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (. Spatial analysis within and between the GUs indicated that the c-diversity was primarily related to higher b-diversity. Throughout the six study years, there were losses of a, b and c-diversity associated spatially with the shallow (reef slope) and deeper (reef terrace) GUs and temporally with the transition in cover from mound corals to fleshy macroalgae and boulder corals. Despite a drastic reduction in the number of species over time, b-diversity continues to be the highest component of c-diversity. The shift transition had a negative effect on a, b and c-diversity, primarily by impacting rare species, leading a group of small and less vulnerable fish species to become common and an important group of rare species to become locally extinct. The maintenance of fish heterogeneity (b-diversity) over time may imply the abetment of vulnerability in the face of local and global changes.
As the impact of anthropogenic activity and climate change continue to accelerate rates of degrad... more As the impact of anthropogenic activity and climate change continue to accelerate rates of degradation on Caribbean coral reefs, conservation and restoration faces greater challenges. At this stage, it is of particular importance in coral reefs to recognize and to understand the structural spatial patterns of benthic assemblages. We developed a field-based framework of a Caribbean reefscape benthic structure by using hermatypic corals as an indicator group of global biodiversity and bio-construction patterns in 11 reefs of the northern sector of the Mesoamerican barrier reef system (nsMBRS). Four hundred and seventy four video-transects (50 m long by 0.4 m wide) were performed throughout a gradient of reef complexity from north to south (∼400 km) to identify coral species, families and ensembles of corals. Composition and abundance of species, families and ensemble showed differences among reefs. In the northern zone, the reefs had shallow, partial reef developments with low diversities, dominated by Acropora palmata, Siderastrea spp., Pseudodiploria strigosa, and Agaricia tenuifolia. In the central and southern zones, reefs presented extensive developments, high habitat heterogeneity, and the greatest diversity and dominance of Orbicella annularis and Orbicella faveolata. These two species determined the structure and diversity of corals in the central and southern zones of the nsMBRS and their bio-construction in these zones is unique in the Caribbean. Their abundance and distribution depended on the reef habitat area, topographic complexity and species richness. Orbicella species complex were crucial for maintaining the biodiversity and bio-construction of the central and southern zones while A. palmate in the northern zones of then sMBRS.
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory variables for the observed biogeographic patterns of fish and coral biodiversity than they were singly. Coral and fish species richness were strongly correlated. Indicators of functional diversity (fish trophic groups and coral morphofunctional groups) followed the same biogeographic patterns as species richness. Reefscape attributes (RA, LCC, and HC) were shown to be good proxies for critical coral reef biodiversity values. This means that simple reefscape attributes can be used to predict more complex biodiversity values of different reef areas. Such predictions can provide an invaluable guide for regional biodiversity assessments, the extrapolation of these results to unsurveyed areas, and guidance for ecoregionalization within large reef tracts where data are sparse.
a b s t r a c t a r t i c l e i n f o Keywords: Beta diversity Caribbean Sea Coral reefs Coral re... more a b s t r a c t a r t i c l e i n f o Keywords: Beta diversity Caribbean Sea Coral reefs Coral reef fish MesoAmerican Reef System (MAR) Spatial patterns Yucatan Peninsula
Additive partitioning was applied to variation in reef fish spatial diversity at Isla Isabel Nati... more Additive partitioning was applied to variation in reef fish spatial diversity at Isla Isabel National Park, Nayarit state, Mexico, and to identify the environmental and spatial variables that best explains it. Analyses included expected and observed species curves, rare species analysis, additive partitioning of alpha-and beta-diversity, and canonical redundancy analysis. A total of 10,517 individuals were recorded from 75 species and 33 reef fish families, representing 85% of expected richness. Species richness beta-diversity was dependent on the site scale, while the alpha-diversity of the Shannon diversity was most significant at the transect scale. Canonical partitioning showed species richness and Shannon diversity was explained by spatially-structured environmental components. Variation in species composition and abundance was explained by a purely environmental component. Therefore, elements of habitat structure (especially corals), topographic complexity, and refuge availability determine fish species diversity. Our results suggest that greater emphasis is required to conserve sites that promote b-diversity, increasing fish spatial diversity. In Isla Isabel, these sites would be mostly those located at eastern and southern of protected sides, where coral reef patches are well represented. The
Tropical landscape and seascape systems are intimately linked by complex ecological relationships... more Tropical landscape and seascape systems are intimately linked by complex ecological relationships that provide environmental services to human societies located in coastal areas and beyond. Paradoxically, nonsustainable activities from these human societies are threatening the functions and benefits of these systems. Anthropogenic processes that damage tropical seascapes are rapidly increasing as a result of coastal and tourism development, increasing human population, unsustainable economic growth, and extensive transformations of natural landscapes. In addition to this overwhelming trend, tropical coastal seascapes are threatened by global climate change. Thus, to address this problem, it is essential to understand the complex ecological relationships between the components of coastal seascape systems and their links to land ecosystems, including the positive and negative effects of humans. The physical and ecological relationships between tropical landscapes and seascapes often define the energy and matter fluxes through which human activities exert their influence on coastal ecosystems. We illustrate these relationships by presenting a case study and conceptual model of coastal and tourism development in the Yucatan Peninsula, Mexico. Scientific knowledge and proposals for better governance practices are available to guide management actions and to protect the connectivity of seascape systems. Nonetheless, political will, coupled with the implementation of local and regional integrated management schemes of coastal zones, is urgent. More examples are needed of inland and coastal human societies that successfully integrate scientific knowledge of the links among ecosystems and their decision-making processes in order to achieve sustainable development based on the services provided by their surrounding seascapes.
As the impact of anthropogenic activity and climate change continue to accelerate rates of degrad... more As the impact of anthropogenic activity and climate change continue to accelerate rates of degradation on Caribbean coral reefs, conservation and restoration faces greater challenges. At this stage, it is of particular importance in coral reefs to recognize and to understand the structural spatial patterns of benthic assemblages. We developed a field-based framework of a Caribbean reefscape benthic structure by using hermatypic corals as an indicator group of global biodiversity and bio-construction patterns in 11 reefs of the northern sector of the mesoamerican barrier reef system (nsMBRS). Four hundred and seventy four video-transects (50 m long by 0.4 m wide) were performed throughout a gradient of reef complexity from north to south (∼400 km) to identify coral species, families and ensembles of corals. Composition and abundance of species, families and ensembles showed differences among reefs. In the northern zone, the reefs had shallow, partial reef developments with low diversities, dominated by Acropora palmata, Siderastrea spp., Pseudodiploria strigosa, and Agaricia tenuifolia. In the central and southern zones, reefs presented extensive developments, high habitat heterogeneity, and the greatest diversity and dominance of Orbicella annularis and Orbicella faveolata. These two species determined the structure and diversity of corals in the central and southern zones of the nsMBRS and their bio-construction in these zones is unique in the Caribbean. Their abundance and distribution depended on the reef habitat area, topographic complexity and species richness. Orbicella species complex were crucial for maintaining the biodiversity and bio-construction of the central and southern zones while A. palmata in the northern zones of the nsMBRS.
ABSTRACT Global climate change and local anthropogenic pressures are among the primary factors le... more ABSTRACT Global climate change and local anthropogenic pressures are among the primary factors leading to the decline of functional biodiversity and critical habitats in coral reefs. Coral bleaching, the potential decreases in dissolved oxygen concentration (deoxygenation) and pH (acidification) in the oceans can induce severe changes in coral reef ecosystem biodiversity and functionality. The main objective of this study was to apply four Ecopath with Ecosim models of a Caribbean coral reef system to individually and collectively model the effects of coral bleaching on the trophic web, deoxygenation on fish, and acidification on calcifying organisms. These three sources of stress were used as forcing functions on several trophic groups depending on the model. The forcing functions were scaled according to the species’ responses achieved in previously tested climate change marine models. For the bleaching model, a mediation function was also considered that represents the degree of coral reef protection on small and intermediate fish groups. The dynamic models were constructed from an extensive database of 171 reef fish species (abundance and biomass) and benthic communities from 13 coral reefs that were evenly distributed parallel to approximately 400 km of the Mexican Caribbean coast as well as fishery landings in this area. Simulations driven with these different forcing and mediation functions predicted different changes in the biomasses of fish and non-fish functional groups as well as the biomass of the functional groups of fished species. Coral bleaching and pH reduction caused a phase shift to a decrease in coral biomass and an increase in primary producer biomass. This shift produced a cascading decrease in the biomass of small and intermediate fish groups. Additionally, the fished functional group biomass increased with coral bleaching but decreased with the effects of decreased oxygen on fish and pH on calcifying organisms. The biomasses of certain macroinvertebrate functional groups were predicted to respond favourably to the combined effect of the sources of stress. However, when all the sources of stress were combined, we found a general decrease of biomass in fish, non-fish, and some commercially valuable fish and macroinvertebrate functional groups, suggesting that the combined effects of stress induced synergistic effects as a result of global climate change and overfishing, which can result in a potential loss of biodiversity and ecosystem services in coral reefs.
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory...
... 3 Laboratorio de Ecosistemas Marinos y Acuicultura (LEMA), Departamento de Ecología, CUCBA, U... more ... 3 Laboratorio de Ecosistemas Marinos y Acuicultura (LEMA), Departamento de Ecología, CUCBA, Universidad de Guadalajara, Carretera Guadalajara–Nogales Km 15.5, AP ... en influir sobre la composición local de las especies y la diversidad en peces y corales: (a) el área del ...
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (
The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious imp... more The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious impacts on coral reef food-webs. We have used an Ecopath-with-Ecosim model to predict the impacts of lionfish invasion on a coral reef community based on pre-invasion fish community data. Forty-six groups were defined, and an initial Ecopath model was balanced with a near-zero biomass of lionfish. In Ecosim, the near-zero biomass was eradicated by applying a very high fishing pressure in the first year of simulation. We subsequently (re-)introduced lionfish with a very low biomass, and allowed them to increase to very high abundance. With a near-zero lionfish biomass, the great majority of mesocarnivorous/omnivorous coral reef fish were predicted to be dominant while sharks were predicted to be the apex predators. Different management scenarios were established in the ecosystem to explore the eradication and resilience of lionfish. The management scenarios showed that if all adult lionfish were exploitable it will in theory be possible to fish the lionfish to a very low level, but the fishing pressure will have to be maintained, or the lionfish will recover. If the largest individuals are unexploitable it will be much more difficult to control the lionfish population.
The structural patterns and trophodynamics of the different fish species in the reef complex of P... more The structural patterns and trophodynamics of the different fish species in the reef complex of Palancar-Chunchakaab, located in the South of Cozumel Island, Mexican Caribbean, were studied. A total of 166 species were identified for the whole reef complex. The analysis of 19,636 recorded and 2291 fish collected allowed the populations to be characterized in terms of diversity, distribution, abundance, dominant species and habitat-fish interactions. Using these parameters, three well defined reef-fish communities were described in relation to three zones: (1) Thalassia zone (THZ), (2) Lagoon (LA) and (3) Shelf-Edge Reef (SER). These communities included 64 species (39% of the total number) that were restricted to a single zone,. The remaining 61% consisted of migratory species that interacted between the defined zones (interdependence of habitat): (1) THZ-LA, (2) THZ-LA-SER, and (3) LA-SER. Diversity was highest in the rainy season in SER (H′ n = 3.3). Analysis of distribution and frequency of 42 of the recorded species revealed that for 25%, life cycle and THZ-SER were closely related. The remaining 75% were more associated with SER or THZ and they used these habitats for feeding, breeding and/or protection. In THZ, > 70% of the total number of species were juveniles; in LA, 40% were preadults-adults; and in SER 80% were adults. The obvious interdependence between habitats suggested a distinct use of the resources by means of migration patterns. By decreasing the order of importance, the major diet types can be ranked as follows: (1) type I carnivores, mainly active by day, preying on small organisms such as crustaceans, polychaetes, mollusks, echinoderms; (2) type II carnivores, nocturnal species consuming larger crustaceans and fish; (3) strict piscivores species; (4) herbivores species; (5) planktivores species; (6) omnivores species; and (7) sessile invertebrate browsers. With the exception of SER, 14%–44% of the type II invertebrate feeders were restricted to the three defined habitats. Of the migratory species, the large invertebrate feeders were the dominant group (21%–41%). The present study suggests that the variation of species diversity patterns and trophic structure are associated with sequential habitat use according to the life cycle. This type of study allowed us to compare the diversity and trophic community of reef fish of the same system and to recognize the energetic interdependence that exists between the habitats.
Journal of Experimental Marine Biology and Ecology, 2008
This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory variables for the observed biogeographic patterns of fish and coral biodiversity than they were singly. Coral and fish species richness were strongly correlated. Indicators of functional diversity (fish trophic groups and coral morphofunctional groups) followed the same biogeographic patterns as species richness. Reefscape attributes (RA, LCC, and HC) were shown to be good proxies for critical coral reef biodiversity values. This means that simple reefscape attributes can be used to predict more complex biodiversity values of different reef areas. Such predictions can provide an invaluable guide for regional biodiversity assessments, the extrapolation of these results to unsurveyed areas, and guidance for ecoregionalization within large reef tracts where data are sparse.
A comparison was made using general trophic models of three coral reef slopes in the Mexican Cari... more A comparison was made using general trophic models of three coral reef slopes in the Mexican Caribbean. Two reef slopes are in semi-protected areas (Boca Paila, Tampalam) and the third is subject to more intense exploitation (Mahahual). The mass-balanced models of the three reef slopes were derived from fish biomass density data obtained directly from field measurements (fish census). Other trophic groups were derived from published sources. Initial parameters for the three reef slopes were calculated using the Ecopath with Ecosim software. Comparisons of model outputs were done to establish differences between reef slope systems that are semi-protected and unprotected from fishing activities. The most significant results include: partition of production was always lowest for the unprotected reef slope; net primary production was three times higher for the semi-protected slopes than for the unprotected one; total catch in the unprotected reef slope was three and eight times higher than the two semi-protected reef slopes; food chain length increased as total catch increased; the calculated trophic level of the catch was relatively lower in the unprotected reef slope; and catch per net primary production (gross efficiency) was higher in the unprotected reef slope than the semi-protected reef slopes. It is concluded that trophic macrodescriptors can serve as a guide to the hard-to-detect negative effects of coral reef management, aid in decision-making, and emphasize the effects that structural descriptors, (e.g. total fish biomass, diversity indices) do not detect.
In 1999 Montastraea faveolata and M. annularis were the most numerous "large" (≥25 cm diameter) s... more In 1999 Montastraea faveolata and M. annularis were the most numerous "large" (≥25 cm diameter) stony corals at ~10 m on fore reefs in the central and southern areas, respectively, of Quintana Roo, México. Reductions in live stony coral cover (from ~25% to ~12% in <10 years) and high recent partial-colony mortality (7-27.5%) are indications of declining reef conditions. Diseases in the five more northerly reefs, as well as tissue loss from the 1998 El Nino Southern Oscillation (ENSO) bleaching event and/or from on-going bleaching during June-July 1999 in the three southernmost reefs, appeared responsible for much of the recent mortality. Although turf algae predominated everywhere, macroalgae were relatively more abundant in the five more northerly reefs (four of which are in a reserve where herbivorous fishes currently are less numerous than further south). Additional perturbations associated with tourism development in the southern area could result in a loss of resilience of these coastal reefs.
Increases of fishing and tourism threaten the natural relationships between reef fish communities... more Increases of fishing and tourism threaten the natural relationships between reef fish communities and their environments. All species of reef fishes were visually assessed in the central and southern Mexican Caribbean in eight fringing reefs, four of which are in a protected biosphere reserve. The sampling design included three spatial scales from tens of meters to tens of kilometers. A total of 9,908 individuals belonging to 128 species and 43 families were identified in 144 belt transects. Zooplankton feeders were the most important trophic group by number of individuals; plant and detritus feeders dominated by number of species. Herbivores were larger in unprotected reefs than in the reserve. Regression analyses showed significant inverse relationships between total fish species density and macroalgal index (a proxy for macroalgal biomass) and, for "large" (≥25 cm diameter) stony corals, partial-colony mortality and live/dead ratio. Significant inverse relationships were also found between mean abundance of the plant and detritus feeders guild and macroalgal index and macroalgae abundance. Geomorphological factors and anthropogenic impacts, both positive (protection) in the reserve and negative (fishing and tourism) in unprotected areas, may explain these spatial patterns in reef-fish community structure.
Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are havi... more Shift transitions in dominance on coral reefs from hard coral cover to fleshy macroalgae are having negative effects on Caribbean coral reef communities. Data on spatiotemporal changes in biodiversity during these modifications are important for decision support for coral reef biodiversity protection. The main objective of this study is to detect the spatiotemporal patterns of coral reef fish diversity during this transition using additive diversity-partitioning analysis. We examined a, b and c fish diversity from 2000 to 2010, during which time a shift transition occurred at Mahahual Reef, located in Quintana Roo, Mexico. Data on coral reef fish and benthic communities were obtained from 12 transects per geomorphological unit (GU) in two GUs (reef slope and terrace) over six years (. Spatial analysis within and between the GUs indicated that the c-diversity was primarily related to higher b-diversity. Throughout the six study years, there were losses of a, b and c-diversity associated spatially with the shallow (reef slope) and deeper (reef terrace) GUs and temporally with the transition in cover from mound corals to fleshy macroalgae and boulder corals. Despite a drastic reduction in the number of species over time, b-diversity continues to be the highest component of c-diversity. The shift transition had a negative effect on a, b and c-diversity, primarily by impacting rare species, leading a group of small and less vulnerable fish species to become common and an important group of rare species to become locally extinct. The maintenance of fish heterogeneity (b-diversity) over time may imply the abetment of vulnerability in the face of local and global changes.
As the impact of anthropogenic activity and climate change continue to accelerate rates of degrad... more As the impact of anthropogenic activity and climate change continue to accelerate rates of degradation on Caribbean coral reefs, conservation and restoration faces greater challenges. At this stage, it is of particular importance in coral reefs to recognize and to understand the structural spatial patterns of benthic assemblages. We developed a field-based framework of a Caribbean reefscape benthic structure by using hermatypic corals as an indicator group of global biodiversity and bio-construction patterns in 11 reefs of the northern sector of the Mesoamerican barrier reef system (nsMBRS). Four hundred and seventy four video-transects (50 m long by 0.4 m wide) were performed throughout a gradient of reef complexity from north to south (∼400 km) to identify coral species, families and ensembles of corals. Composition and abundance of species, families and ensemble showed differences among reefs. In the northern zone, the reefs had shallow, partial reef developments with low diversities, dominated by Acropora palmata, Siderastrea spp., Pseudodiploria strigosa, and Agaricia tenuifolia. In the central and southern zones, reefs presented extensive developments, high habitat heterogeneity, and the greatest diversity and dominance of Orbicella annularis and Orbicella faveolata. These two species determined the structure and diversity of corals in the central and southern zones of the nsMBRS and their bio-construction in these zones is unique in the Caribbean. Their abundance and distribution depended on the reef habitat area, topographic complexity and species richness. Orbicella species complex were crucial for maintaining the biodiversity and bio-construction of the central and southern zones while A. palmate in the northern zones of then sMBRS.
The explanatory value of four hypotheses for geographic variation in total species richness and s... more The explanatory value of four hypotheses for geographic variation in total species richness and species richness was evaluated per family in coral and fish communities in the North Sector of the Mesoamerican Barrier Reef System (NS-MBRS). The four hypotheses emphasize different reefscape attributes that are important for coral and fish: reef area (RA), live coral cover (LCC), habitat complexity (HC), and coral richness itself and for fish. For both coral and fish communities, we estimated the total number of species and number of species per family on 11 coral reefs along a 400-km section of NS-MBRS. Hard coral cover and HC were quantified using line and chain transects, respectively, and RA was estimated using Landsat TM images and a geographic information system. We used multiple regression and canonical redundancy analysis to study the fish-environment and coral-environment relationships. The three reefscape features (RA, LCC, and HC) in combination were much stronger explanatory variables for the observed biogeographic patterns of fish and coral biodiversity than they were singly. Coral and fish species richness were strongly correlated. Indicators of functional diversity (fish trophic groups and coral morphofunctional groups) followed the same biogeographic patterns as species richness. Reefscape attributes (RA, LCC, and HC) were shown to be good proxies for critical coral reef biodiversity values. This means that simple reefscape attributes can be used to predict more complex biodiversity values of different reef areas. Such predictions can provide an invaluable guide for regional biodiversity assessments, the extrapolation of these results to unsurveyed areas, and guidance for ecoregionalization within large reef tracts where data are sparse.
a b s t r a c t a r t i c l e i n f o Keywords: Beta diversity Caribbean Sea Coral reefs Coral re... more a b s t r a c t a r t i c l e i n f o Keywords: Beta diversity Caribbean Sea Coral reefs Coral reef fish MesoAmerican Reef System (MAR) Spatial patterns Yucatan Peninsula
Additive partitioning was applied to variation in reef fish spatial diversity at Isla Isabel Nati... more Additive partitioning was applied to variation in reef fish spatial diversity at Isla Isabel National Park, Nayarit state, Mexico, and to identify the environmental and spatial variables that best explains it. Analyses included expected and observed species curves, rare species analysis, additive partitioning of alpha-and beta-diversity, and canonical redundancy analysis. A total of 10,517 individuals were recorded from 75 species and 33 reef fish families, representing 85% of expected richness. Species richness beta-diversity was dependent on the site scale, while the alpha-diversity of the Shannon diversity was most significant at the transect scale. Canonical partitioning showed species richness and Shannon diversity was explained by spatially-structured environmental components. Variation in species composition and abundance was explained by a purely environmental component. Therefore, elements of habitat structure (especially corals), topographic complexity, and refuge availability determine fish species diversity. Our results suggest that greater emphasis is required to conserve sites that promote b-diversity, increasing fish spatial diversity. In Isla Isabel, these sites would be mostly those located at eastern and southern of protected sides, where coral reef patches are well represented. The
Tropical landscape and seascape systems are intimately linked by complex ecological relationships... more Tropical landscape and seascape systems are intimately linked by complex ecological relationships that provide environmental services to human societies located in coastal areas and beyond. Paradoxically, nonsustainable activities from these human societies are threatening the functions and benefits of these systems. Anthropogenic processes that damage tropical seascapes are rapidly increasing as a result of coastal and tourism development, increasing human population, unsustainable economic growth, and extensive transformations of natural landscapes. In addition to this overwhelming trend, tropical coastal seascapes are threatened by global climate change. Thus, to address this problem, it is essential to understand the complex ecological relationships between the components of coastal seascape systems and their links to land ecosystems, including the positive and negative effects of humans. The physical and ecological relationships between tropical landscapes and seascapes often define the energy and matter fluxes through which human activities exert their influence on coastal ecosystems. We illustrate these relationships by presenting a case study and conceptual model of coastal and tourism development in the Yucatan Peninsula, Mexico. Scientific knowledge and proposals for better governance practices are available to guide management actions and to protect the connectivity of seascape systems. Nonetheless, political will, coupled with the implementation of local and regional integrated management schemes of coastal zones, is urgent. More examples are needed of inland and coastal human societies that successfully integrate scientific knowledge of the links among ecosystems and their decision-making processes in order to achieve sustainable development based on the services provided by their surrounding seascapes.
Uploads
Papers by Jesus Arias