Biogeografia, ecologia e prioridades espaciais para a conservação de vertebrados marinhos brasileiros

Orientador : Prof. Dr. Henry Louis SpachOrientador : Prof. Dr. Jean-Christophe JoyeuxTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Ecologia e Conservação. Defesa: Curitiba, 17/03/2014Inclui referênciasResumo: Nesse estudo, foram investigadas as mudanças na estrutura da ictiofauna estuarina em diferentes escalas geográficas, os processos ecológicos subjacentes a essas mudanças, bem como a localização de áreas prioritárias para a conservação na zona marinha brasileira. No Capítulo 1, um desenho de amostragem hierárquico foi usado para comparar a variação na estrutura das assembleias de peixes entre duas escalas espaciais e para estimar os efeitos individuais e sinergéticos de alguns parâmetros ambientais e da distância geográfica na estruturação da fauna. Para isso, foram amostradas oito áreas separadas por 0,7-25 km (escala local) dentro de cada um dos cinco estuários separados por 970-600 km (escala regional). As análises revelaram diferenças significativas na estrutura das assembleias (em termos de biomassa relativa e presença/ausência das espécies) para ambas as escalas e que a variação regional foi comparativamente maior do que a variação local. Porém, os cinco estuários amostrados segregaram-se em dois grupos amplamente congruentes com as províncias biogeográficas Brasileira e Argentina. Três variáveis ambientais (temperatura média da água no mês mais frio, área de manguezal e precipitação média anual) e a distância entre os estuários explicaram, respectivamente, 44,8 e 16,3% da variabilidade regional na biomassa relativa das espécies. Em escala local, os resultados sugerem que as assembleias de diferentes estuários são estruturadas por fatores distintos. No Capítulo 2, os padrões geográficos de riqueza de espécies e raridade da ictiofauna estuarina foram mapeados e integrados para identificar regiões importantes para a conservação na costa brasileira. Além disso, também foi analisada a efetividade do sistema nacional de áreas protegidas para representar essas regiões. Quarenta e oito bandas, com 0,25° de latitude cada, foram consideradas prioritárias para a conservação, por possuírem simultaneamente uma alta riqueza de espécies e assembleias relativamente raras. Também foi verificado que o sistema atual de áreas protegidas é ineficiente para proteger essas bandas. Por fim, no Capítulo 3, foram elaboradas alternativas para a expansão das áreas marinhas protegidas (AMPs) em águas brasileiras, que maximizam a representação das espécies e evitam conflitos com atividades econômicas relevantes. Para isso, foram utilizados dados de distribuição de 750 espécies de vertebrados marinhos (incluindo mamíferos, aves, tartarugas e peixes), das AMPs existentes e das concessões para exploração/produção de petróleo e gás natural na Zona Econômica Exclusiva do País. As soluções elaboradas mostraram que uma rede de AMPs, abrangendo 10% da área de estudo com alta prioridade para a conservação, poderia proteger, em média, entre 85,8 e 86,5% da distribuição das espécies. Foi constatado que a inclusão das AMPs existentes e das concessões para exploração de petróleo e gás no processo de priorização causou somente uma pequena perda na representação de espécies em perigo e ameaçadas de extinção. Os resultados sugerem, no entanto, que é possível compatibilizar a produção atual de petróleo e gás com a expansão da rede nacional de AMPs. As informações apresentadas nesse estudo podem contribuir para a tomada de decisões vinculadas ao objetivo do Brasil, de proteger 10% da sua zona marinha e costeira até 2020. Palavras-chave: comunidade de peixes, biodiversidade, estuários, planejamento para conservação, áreas marinhas protegidas, raridade.Abstract: The present study aims to investigate changes in estuarine ichthyofauna across different spatial scales, the ecological process underlining these changes, as well as the localization of priority areas for conservation at Brazilian marine zone. In Chapter 1, a hierarchical sampling design was used to quantify variations in assemblage structures of Brazilian estuarine fish across two spatial scales and to estimate the individual and synergetic effects of selected environmental variables and of geographical distance on the ichthyofauna structure. For this analysis, eight areas separated by 0.7 to 25 km (local scale) were sampled in five estuaries separated by 970 to 6000 km (regional scale). Multivariate analysis revealed that assemblage structure varied significantly in terms of relative biomass and presence/absence of species on both scales, and that the regional variation was greater than the local variation for either dataset. However, the five estuaries sampled segregated into two major groups largely congruent with the Brazilian and Argentinian biogeographic provinces. Three environmental variables (mean temperature of the coldest month, mangrove area and mean annual precipitation) and distance between estuaries explained 44.8 and 16.3%, respectively, of the regional-scale variability in the species relative biomass. At the local scale, the importance of environmental predictors for the spatial structure of the assemblages differed between estuarine systems. In Chapter 2, geographic patterns of species richness and rarity of the estuarine ichthyofauna were mapped and integrated to identify important regions for biodiversity conservation across the Brazilian coast. Furthermore, also was analyzed the effectiveness of the national system of protected areas to represent these regions. Forty-eight bands of 0.25° latitude each were recognized as conservation priorities by harbor simultaneously high species richness and assemblages that are relatively rare. Also was found that the existing system of protected areas is inefficient to represent priority bands identified in this study. Lastly, in Chapter 3 were developed alternatives for the expansion of current marine protected areas (MPAs) in Brazilian waters that maximize species representation and reduce potential conflicts with relevant economic activities. For this were utilized distribution data of 750 marine vertebrate species (including mammals, birds, turtles and fishes), of established MPAs and of the areas concessioned for oil and gas exploitation. The results showed that a MPA network encompassing 10% of the study area with high conservation priority would protect, on average, between 85.8 and 86.5% of species distribution. It was found that incorporating existing MPAs and areas concessioned for oil and gas exploitation in the prioritization process caused only a small loss in representation of near-threatened and threatened species. The results highlight, therefore, that it is possible to reconcile current offshore oil and gas production with the expansion of the national MPA network, without significant losses in species' representation. The solutions presented here may be useful as scientific support in political negotiations about Brazil's commitment to protect 10% of its coastal and marine areas by 2020. Key-words: fish communities, biodiversity, estuaries, conservation planning, marine protected areas, rarity

Peixes do Complexo Estuarino de Paranaguá, Atlântico Sul Oeste

The objective of this work was to present an updated checklist of the currently known fishes in the Paranagua Estuarine Complex (PEC) and provides comments on conservation status for the treated species. We used a large dataset derived from a pool of studies which have been conducted within there along the last 30 years. Each study was based on monthly samplings and conducted in several estuarine habitat; thus, the pool covers practically all estuarine habitats and takes into account the seasonal cycle in the system. The PEC ichthyofauna represents a mixture between that fauna typical from the tropical Brazilian coast and that with affinities of temperate Argentinean and Uruguayan zones. The PEC harbors a rich fish fauna of 213 species, inserted in the families that are common along the Brazilian coast. Only a minor part (8%) of the PEC fish fauna was evaluated as regards the conservation status, mostly because of the lack of basic biological and ecological information for most species. Despite part of the among-estuaries differences are due to different and incomplete sampling efforts, the richness in the PEC is surprisingly higher than other systems in Brazil and around world, which emphasize the importance of the region for global biodiversity conservation.CAPES Foundatio

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http://dx.doi.org/10.5007/2175-7925.2008v21n4p73A densidade relativa (no de tocas/m2) e a distribuição espacial do caranguejo Ocypode quadrata foram avaliadas em três praias arenosas do município de Vila Velha-ES: Itaparica, Itapoã e Praia da Costa. Nas três praias, as amostragens foram conduzidas nos dias 25/05, 13/06, 26/06 e 11/07/2006. Em cada dia, foram distribuídos aleatoriamente por praia, dois transectos de 5m de largura perpendiculares a linha d’água, divididos em retângulos de 2 x 5m, abrangendo toda faixa de areia. Em cada transecto, todas as tocas foram contadas, os diâmetros da abertura foram medidos (mm) e a localização em relação à linha d’água de cada toca foi anotada. A praia de Itaparica apresentou a maior densidade média de tocas (média = 0,33, DP = ± 0,26), seguida pela Praia da Costa (0,16 ± 0,14) e Itapoã (0,08 ± 0,02). Com relação ao diâmetro das tocas, Itaparica e Itapoã possuíram as maiores médias (16,2 ± 8,88; 16,2 ± 8,91, respectivamente) e Praia da Costa a menor (12,6 ± 6,40). A densidade e o diâmetro das tocas diferiram signifi cativamente entre as praias. Foi observado que as tocas de menor diâmetro predominaram nas áreas próximas à linha d’água e as tocas com maiores diâmetros na parte superior da praia. O fluxo de pessoas e a passagem do veículo de limpeza parece influenciarem na densidade e nos padrões de distribuição espacial encontrados para O. quadrata.Density and spatial distribution of the crab Ocypode quadrata (Fabricius, 1787) (Crustacea, Ocypodidae) on three sandy beaches of Espírito Santo, Brazil. The relative density (number of burrows/m2) and spatial distribution of the crab Ocypode quadrata were evaluated on three sandy beaches of Vila Velha-ES: Itaparica, Itapoã and Praia da Costa. These beaches were sampled on 05/25, 06/13, 06/26 and 07/11/2006. On  each day, two 5m width transects were randomly distributed on each beach, perpendicular to the waterline anddivided into 2 x 5m rectangles. Within each transect, all burrows were counted, the diameters were measured (mm), and their locations in relation to the waterline were recorded. Itaparica beach presented a greater mean density of burrows (mean = 0.33, SD = ± 0.26), followed by Praia da Costa (0.16 ± 0.14) and Itapoã (0.08 ± 0.02). Regarding the burrow diameters, Itaparica and Itapoã showed greater values (16.2 ± 8.88 and 16.2 ± 8.91, respectively) than Praia da Costa (12.6 ± 6.40). The density of burrows and the burrow diameters differedsignifi cantly among the beaches. A greater abundance of small burrows occurred near the waterline and a greater abundance of large burrows were situated on the upper beach. The fl ux of people and the passage of the urban cleansing vehicles apparently had an infl uence on the density and spatial distribution standards found for the O. quadrata crabs

Density and spatial distribution of the crab Ocypode quadrata (Fabricius, 1787) (Crustacea, Ocypodidae) on three sandy beaches of Espírito Santo, Brazil

The relative density (number of burrows/m2) and spatial distribution of the crab Ocypode quadrata were evaluated on three sandy beaches of Vila Velha-ES: Itaparica, Itapoã and Praia da Costa. These beaches were sampled on 05/25, 06/13, 06/26 and 07/11/2006. On each day, two 5m width transects were randomly distributed on each beach, perpendicular to the waterline and divided into 2 x 5m rectangles. Within each transect, all burrows were counted, the diameters were measured (mm), and their locations in relation to the waterline were recorded. Itaparica beach presented a greater mean density of burrows (mean = 0.33, SD = ± 0.26), followed by Praia da Costa (0.16 ± 0.14) and Itapoã (0.08 ± 0.02). Regarding the burrow diameters, Itaparica and Itapoã showed greater values (16.2 ± 8.88 and 16.2 ± 8.91, respectively) than Praia da Costa (12.6 ± 6.40). The density of burrows and the burrow diameters differed significantly among the beaches. A greater abundance of small burrows occurred near the waterline and a greater abundance of large burrows were situated on the upper beach. The flux of people and the passage of the urban cleansing vehicles apparently had an influence on the density and spatial distribution standards found for the O. quadrata crabs

Decapod Community Composition is Seasonally Driven by Different Environmental Factors in an Estuarine-Coastal Gradient (Eastern Brazil)

Crustacean communities are shaped by a series of ecological processes, but the degree to which different spatial and environmental dimensions affect them in surrounding estuarine-coastal gradients remains unclear. Here we analyzed decapod community data from the Doce River estuary and its adjacent marine coast, to test and quantify the effects that spatial and environmental factors have had on these communities three years after the Fundão mining dam failure of November 2015. We sampled communities monthly from October 2018 to September 2019 in 18 sampling sites distributed in three zones (estuary, nearshore, and offshore), resulting in 216 samples and 29 recorded taxa. Spatial eigenvector-based methods and variation partitioning approaches were used to test and quantify the pure and joint effects of spatial and environmental processes on the communities over different seasons. The spatial structures of the community composition presented differences among the four studied seasons, being driven by environmental heterogeneity as well as spatial processes unrelated to our measured variables (temperature, salinity, depth, turbidity, dissolved oxygen and pH). Specifically, the species composition and species richness responded the most to turbidity, pH, and depth during the rainy seasons, as well as salinity during the dry seasons. The variability of decapod composition (crabs and shrimps) surrounding the Doce River mouth is seasonally affected by a different set of environmental and spatial factors, with low intrusions of saltwater in the estuarine sector impacting the distribution of stenohaline marine species. Our results both partly uncover and emphasize the complexity resulting from environmental heterogeneity and anthropic pressures, stressing the need for further studies on local spatio-temporal dynamics of decapod fauna and other organisms to inform conservation and management actions