ICB - Artigos publicados em periódicos

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Coupling environment and physiology to predict effects of climate change on the taxonomic and functional diversity of fish assemblages in the Murray-Darling Basin, Australia
(2019-11) Oliveira, Anielly Galego de; Fernandes, Dayani Bailly; Cassemiro, Fernanda Aparecida da Silva; Couto, Edivando Vitor do; Bond, Nick; Gilligan, Dean; Rangel, Thiago Fernando Lopes Valle de Britto; Agostinho, Angelo Antonio; Kennard, Mark J.
This study uses species distribution modeling and physiological and functional traits to predict the impacts of climate change on native freshwater fish in the Murray-Darling Basin, Australia. We modelled future changes in taxonomic and functional diversity in 2050 and 2080 for two scenarios of carbon emissions, identifying areas of great interest for conservation. Climatic-environmental variables were used to model the range of 23 species of native fish under each scenario. The consensus model, followed by the physiological filter of lethal temperature was retained for interpretation. Our study predicts a severe negative impact of climate change on both taxonomic and functional components of ichthyofauna of the Murray- Darling Basin. There was a predicted marked contraction of species ranges under both scenarios. The predictions showed loss of climatically suitable areas, species and functional characters. There was a decrease in areas with high values of functional richness, dispersion and uniqueness. Some traits are predicted to be extirpated, especially in the most pessimistic scenario. The climatic refuges for fish fauna are predicted to be in the southern portion of the basin, in the upper Murray catchment. Incorporating future predictions about the distribution of ichthyofauna in conservation management planning will enhance resilience to climate change.
Diel variation in the ascent of fishes up an experimental fish ladder at Itaipu Reservoir: fish size, reproductive stage and taxonomic group influences
(Sociedade Brasileira de Ictiologia, 2007-06) Fernandez, Domingo Rodriguez; Agostinho, Angelo Antonio; Bini, Luis Mauricio; Pelicice, Fernando Mayer
In this study, we evaluated the fish ascent in the experimental ladder at Itaipu Reservoir (Paraná State, Brazil), in relation to diel variation, fish size, reproductive stages and species composition. The study was carried out from October, 1995 to February, 1996 and from November, 1996 to January, 1997 at two points on the ladder (boxes at heights of 10 and 27 m). Twenty-two species were recorded, and Prochilodus lineatus, Pimelodus maculatus, Leporinus obtusidens, Schizodon borellii and Leporinus friderici accounted for 86.6 % of the total catch. Fish length did not differ between diel periods and boxes. On the other hand, fish abundance of the main species was significantly influenced by box position, reproductive stage and diel period. The higher box showed lower abundance, suggesting some selectivity in ascension. The ability to ascend the ladder did not show any relationship with reproductive migration, since non-reproductive adults comprised most of the catch. An interesting finding is that the major taxonomic groups showed specific diel preferences in ascending the ladder: Characiformes ascended the ladder predominantly during daylight, whereas Siluriformes migrated at night. These results emphasize how complex ladders are as management tools, and stress the need to acquire information on several aspects as a condition to achieve conservation goals.
Diversity gradients of Neotropical freshwater fish: evidence of multiple underlying factors in human-modified systems
(2016) Fernandes, Dayani Bailly; Cassemiro, Fernanda Aparecida da Silva; Winemiller, Kirk O.; Diniz Filho, José Alexandre Felizola; Agostinho, Angelo Antonio
Aim Contemporary patterns of species diversity are the result of a hierarchy of natural processes and modern anthropogenic influences. However, studies of these patterns in human-modified systems from a macroecological perspective are lacking. Considering that fish assemblages in reservoirs reflect both long-term evolutionary responses of species and shorter term responses to anthropogenic stressors, we employed a multi-hypothesis approach using different magnitudes of predictors to analyse the processes that drive fish diversity in reservoirs at a broad spatial scale. Location Brazil. Methods We derived species richness from an extensive database of fish inhabiting Neotropical reservoirs, and using multiple regression analysis, we tested seven hypotheses that link species richness to continuous variables associated with regional, local and population components. We analysed the spatial structure using Moran's I autocorrelation coefficients and used spatial eigenvector mapping to explicitly account for the spatial component when testing the hypotheses by multiple regressions. Partial regressions were performed to map the relative contributions of the different components in explaining species richness. Results Predictors related to six hypotheses were retained in the best-fit models, and our data supported the species–energy, metabolic, species–area, species–distance from the source and time of habitat alteration hypotheses. However, the predictions of the population abundance hypothesis (PAH) were not supported by the data. The shared effects of the different components explained the greatest proportion of the variation in species richness, indicating that distinct mechanisms related to these alternative hypotheses interact or are not spatially independent. Main conclusions Our findings indicate that the latitudinal diversity gradient typically displayed by freshwater fish is maintained in human-modified habitats, such as reservoirs, and that multiple mechanisms drive fish diversity in reservoirs over large spatial scales. The lack of support for the PAH implies that mechanisms structuring diversity patterns can be influenced by anthropogenic stressors.
Drivers and spatial patterns of population synchrony of fish species in a floodplain
(2022) Granzotti, Rafaela Vendrametto; Agostinho, Angelo Antonio; Bini, Luis Mauricio
Spatial synchrony is the correlation between the temporal dynamics of local populations. This pattern may be driven by spatially correlated environmental variation (i.e., Moran effect), dispersal and trophic interactions. Investigating geographic patterns of synchrony can help disentangle the relative importance of these drivers. Using fish abundance data from long-term ecological research (17 years) in the Upper Paraná River floodplain, we studied the relative roles of dispersal distance, density dependence differences, and environmental synchrony in determining spatial synchrony of the most common species in this floodplain. We also investigated the geography of spatial synchrony by estimating modularity and site-level contributions to synchrony and anti-synchrony networks. We found positive spatial synchrony for most species, but levels were relatively low. For most species, our explanatory matrices were poorly related to spatial synchrony. We detected modular structures in some species networks, which reflected complex spatial patterns in synchrony. We also detected sites with high importance to spatial synchrony patterns that could be managed to increase metapopulation stability. The variable levels of spatial synchrony for fish species in the Upper Paraná River floodplain implies the need to monitor several sites to understand their dynamics in this region. Also, some migratory species of high importance to regional fisheries, such as Prochilodus lineatus, may deserve special monitoring attention due to the increased regional extinction risk associated with their high levels of spatial synchrony. Finally, we speculate that hydrological manipulation from upstream reservoirs should consider the timing of water releases to avoid spatially correlated population declines.
Environmental factors related to entry into and ascent of fish in the experimental ladder located close to Itaipu Dam
(Sociedade Brasileira de Ictiologia, 2007-06) Fernandez, Domingo Rodriguez; Agostinho, Angelo Antonio; Bini, Luis Mauricio; Gomes, Luiz Carlos
We evaluated the seasonality of the ascent of fish in an experimental ladder located close to Itaipu Dam, and its relationships to reproduction, temperature, river level and discharge. Samplings of fish and measurements of abiotic factors were performed from February, 1995 through January, 1997, in two resting pools of the ladder. Pool A was located 10 m above the mean level of the Paraná River; Pool B was located at the upper end of the ladder, at a height of 27 m. Autoregressive models were used to remove the temporal dependence between observations. Residuals of the models were used to relate, using Pearson’s correlation coefficient, the densities of fish to the environmental variables. Clear patterns of seasonality were observed for temperature. River level, turbine discharge and spillway discharge, although they showed no clear seasonal dynamics, were timedependent, because the autocorrelation coefficients for different k values were significant. In the samples of larger-sized fish, 23 species were recorded during the two years of study. Most of the individuals were in a non reproductive state, and about 90% of the individuals belonged to only six species. The temporal variability in total abundance, considering all species, indicated a pattern of seasonal variation; high abundances occurred from October through February (75%) and in Pool A (61% of the 1343 individuals sampled). Low abundances were recorded during winter, with the correlogram of total density confirming this tendency. In the samples of smaller-sized species, six species were recorded, with all six present in both pools, but more frequent in the first pool (64%). Bryconamericus stramineus comprised 99% of the total numbers of smaller fish in the samples. The total abundance of small species showed different temporal patterns of seasonal variation in the two years of study.
Environmental filters predict the trait composition of fish communities in reservoir cascades
(2017) Santos, Natália Carneiro Lacerda dos; Santana, Herick Soares de; Gonçalves Ortega, Jean Carlo; Dias, Rosa Maria; Stegmann, Lis Fernandes; Araújo, Isabela Maria da Silva; Severi, William; Bini, Luis Mauricio; Gomes, Luiz Carlos; Agostinho, Angelo Antonio
Dam construction alters flow regimes and can change the composition of aquatic communities. Using data from three Brazilian hydrographic basins, we tested the hypothesis that reservoir cascades act as environmental filters for fish traits. This dataset included information on different environmental variables and fish traits (diet, migration, fecundation, parental care, position in the water column, and body size), and we used multivariate analysis (partial RLQ) to quantify the relationships between environmental variables, species abundance and traits. We found that the abundance of migratory species declined towards downstream reservoirs, which tend to be smaller and less turbid with a shorter water residence time than upstream reservoirs. We also found evidence of an association between reservoir age and the domination of fish communities by small-sized species with parental care, external fecundation, and benthic habits. Our findings suggest that particular fish traits are selected for across reservoir cascades.
Food spectrum and trophic structure of the ichthyofauna of Corumbá reservoir, Paraná river Basin, Brazil
(Sociedade Brasileira de Ictiologia, 2006-03) Agostinho, Karla Danielle Gaspar da Luz; Bini, Luis Mauricio; Fugi, Rosemara; Agostinho, Angelo Antonio; Júlio Júnior, Horácio Ferreira
In this paper we evaluate plasticity of fish concerning diet. We expect that sampling over a large temporal and spatial scale, including environmental changes such as impoundments, will allow us to cover most of the diet plasticity. We also evaluate the efficacy of ordination method in discriminating trophic groups based on fish species diet. Data were obtained from 17 sampling stations sampled monthly from March/96 to February/99 in the Corumbá river drainage, before and after the formation of the Corumba reservoir. Diet was determined analysing 9,177 stomach contents from 64 fish species. Trophic categories were discriminated by a non-hierarchic grouping analysis named k-means, applied to diet data. Most of the species presented great trophic plasticity, eating a great variety of food items. Resources availability, estimated from all fish stomach contents, was similar among environments, except in creeks, where it varied more with a large importance of terrestrial insects. K-means present satisfactory results, identifying nine trophic groups (detritivores, herbivore-piscivores, insectivore-herbivores, omnivores, invertivores, aquatic insectivores, piscivore-insectivores, piscivores and herbivores).
Host diversity, phylogenetic relationships and local environmental factors drive infection patterns of a non-native parasite in tropical floodplain fish assemblages
(2021) Lima Junior, Dilermando Pereira; Luz, Sybelle Bellay da; Hoeinghaus, David Joseph; Bini, Luis Mauricio; Lima, Luciano Benedito de; Yotoko, Karla Suemy Clemente; Agostinho, Angelo Antonio
Biodiversity, biological traits of potential host species, and environmental conditions may mediate the emergence of new diseases. We assessed the relative influence of such factors on patterns of infection by Austrodiplostomum compactum (Digenea, Diplostomidae) in fish assemblages of the Upper Paraná River floodplain, Brazil. Multiple infection parameters were modeled at the community and species levels using phylogenetic diversity (PD), abundance (total and for a main reservoir species Plagioscion squamosissimus), local environmental conditions and phylogenetic distance from P. squamosissimus (Dis_Plag). In total, 108 fish species were collected and 28 were infected. At the community level, mean parasite abundance and mean infection intensity were positively associated with PD and the interaction between PD and environmental conditions, whereas host richness was negatively associated with PD. The complementary results indicate a biodiversity sampling effect rather than dilution effect. Environmental conditions often had the strongest coefficients in community-level models and mediated associations between infection parameters and other factors. At the species level, consistent negative associations between infection parameters and Dis_Plag indicate phylogenetic niche conservatism of parasites. Integration of community and species-level analyses demonstrates that phylogenetic diversity can affect host–parasite interactions in multiple ways, but that the associations depend on phylogenetic relationships and environmental conditions.
Large-scale degradation of the Tocantins-Araguaia river basin
(2021) Pelicice, Fernando Mayer; Agostinho, Angelo Antonio; Akama, Alberto; Andrade Filho, José Dilermando; Santos, Valter Monteiro de Azevedo; Barbosa, Marcus Vinicius Moreira; Bini, Luis Mauricio; Brito, Marcelo Fulgêncio Guedes; Candeiro, Carlos Roberto dos Anjos; Caramaschi, Erica Maria Pellegrini; Carvalho, Priscilla; Diniz Filho, José Alexandre Felizola
The Tocantins-Araguaia Basin is one of the largest river systems in South America, located entirely within Brazilian territory. In the last decades, capital-concentrating activities such as agribusiness, mining, and hydropower promoted extensive changes in land cover, hydrology, and environmental conditions. These changes are jeopardizing the basin’s biodiversity and ecosystem services. Threats are escalating as poor environmental policies continue to be formulated, such as environmentally unsustainable hydropower plants, large-scale agriculture for commodity production, and aquaculture with non-native fish. If the current model persists, it will deepen the environmental crisis in the basin, compromising broad conservation goals and social development in the long term. Better policies will require thought and planning to minimize growing threats and ensure the basin’s sustainability for future generations.
Negative effect of turbidity on prey capture for both visual and non-visual aquatic predators
(2020) Gonçalves Ortega, Jean Carlo; Figueiredo, Bruno Renaly Souza; Graça, Weferson Júnio da; Agostinho, Angelo Antonio; Bini, Luis Mauricio
1. Turbidity plays an important role in aquatic predator–prey interactions. Increases in turbidity are expected to reduce prey capture rates, especially for visually oriented predators. However, there is also evidence indicating that turbidity may have little or no effect on predation rates. 2. Here, we conducted a systematic review and meta-analysis of the relationship between turbidity and capture rate. We explored possible sources of heterogeneity in the effect sizes (capture strategy, predator's body size, relative eye size and turbidity range in the experiments) while controlling for the dependence among effects sizes and phylogenetic relationships among predator species. 3. We found a consistent negative effect of turbidity on prey capture and that turbidity range (manipulated in the experiments) was the main factor accounting for between-study variation in effect sizes. Also, capture rates of both visually and non-visually oriented predators decreased with an increase in turbidity. In addition, for visually oriented fish predators, the relative eye size did not influence the effect sizes. 4. Despite the paucity of studies for some groups of aquatic predators (mainly in tropical regions), we provide corroborative evidence that turbidity is a critical environmental factor controlling predator–prey interactions. This result is especially relevant considering that changes in turbidity is a human-induced pervasive environmental alteration resulted from, among other mechanisms, runoff after deforestation, eutrophication or oligotrophication in reservoir cascades, which imply changes in predator–prey interactions.
Rescue effect drives local persistence of fish species in the upper Paraná river floodplain
(2021) Granzotti, Rafaela Vendrametto; Cassemiro, Fernanda Aparecida da Silva; Agostinho, Angelo Antonio; Bini, Luis Mauricio
The interspecific variation in spatial distribution has been frequently studied in macroecology, but cross-species differences in temporal occupancy (the number of times a species has been recorded in a site, i.e. local persistence) are seldom investigated. Here we aim to determine the relative importance of different predictors of species temporal occupancy, including local abundance, body size, range size, biological traits, environmental niche metrics, and proportion of the sites occupied (mean landscape occurrence). Using 17 years of data on 93 Neotropical fish species collected at the Upper Paraná River floodplain, we modelled temporal occupancy in six floodplain lakes, controlling for phylogenetic dependence, and investigated whether the relative importance of predictors was maintained across sites. Mean landscape occurrence and mean local abundance were the main predictors of temporal occupancy in all six lakes. Body size was also important in most lakes. The concordance in the ranks of predictors was high, indicating consistency in the mechanisms behind temporal occupancy across sites. Our results indicate the importance of metapopulation processes, especially the rescue effect, in determining long-term persistence of fish local populations in floodplains. The influence of spatial occupancy on local persistence implies that protecting a large number of habitats in the landscape might reduce the risk of local extinction of species, thus maintaining biodiversity levels in the system.
Similarities in correlates of native and introduced fish species richness distribution in Brazilian reservoirs
(2018) Gonçalves Ortega, Jean Carlo; Agostinho, Angelo Antonio; Santos, Natália Carneiro Lacerda dos; Agostinho, Karla Danielle Gaspar da Luz; Oda, Fabrício Hiroiuki; Severi, William; Bini, Luis Mauricio
We assessed the relationships among native and introduced fish species richness and a set of explanatory variables, including area, altitude, reservoir age, temperature, human influence index and fish abundance. We expected to find different relationships based on species origin (i.e., native or introduced). Based on compiled data from Brazilian reservoirs, we modeled the variation in the number of native and introduced fish species by generalized linear mixed models with different spatial autocorrelation structures. Reservoirs located in warmer regions and with higher fish abundance showed higher species richness of both native and introduced fish. Reservoir age tended to be negatively correlated with native species richness. Our results suggest that reservoir communities in warmer regions may be more resistant to local extinctions caused by impoundments, but they are more susceptible to species introductions. Our results also highlight that an extinction debt can be expected for native species because older reservoirs showed lower native species richness.
Spatial synchrony of a highly endemic fish assemblage (Segredo reservoir, Iguacu river, Paraná state, Brazil)
(Instituto Internacional de Ecologia, 2005-08) Domingues, Wladimir Marques; Agostinho, Angelo Antonio; Bini, Luis Mauricio
In this study, patterns of spatial synchrony in population fluctuations (cross-correlation) of an endemic fish assemblage of a Neotropical reservoir (Segredo Reservoir, Iguaçu River, Paraná State, Brazil) were reported. First, the level of population synchrony for 20 species was estimated. Second, population synchrony was correlated, using the Mantel test, with geographical distances among sites (n = 11) and also environmental synchrony (temperature). Nine species presented significant correlations between spatial synchrony and geographic distances (Astyanax sp. b, Astyanax sp. c, Pimelodus sp., Hoplias malabaricus, Crenicichla iguassuensis, Hypostomus derbyi, Hypostomus myersi, Rhamdia branneri, and R. voulezi). Considering the ecology of the species and the significant relationship between population and environmental synchronies, it seems that environmental stochasticity is the most plausible hypothesis in explaining the observed synchrony patterns.
The conservation of migratory fishes in the second largest river basin of South America depends on the creation of new protected areas
(2021) Fernandes, Dayani Bailly; Silva, Valéria Flávia Batista da; Cassemiro, Fernanda Aparecida da Silva; Silva, Priscila Lemes de Azevedo; Graça, Weferson Júnio da; Oliveira, Anielly Galego de; Couto, Edivando Vitor do; Ferreira, José Hilário Delconte; Ré, Reginaldo; Rangel, Thiago Fernando Lopes Valle de Britto; Agostinho, Angelo Antonio
Freshwater ecosystems, providing valuable goods and services to humans, have been subjected to multiple human impacts, among which climate change plays a central role in threats to species. It is expected that protected areas, the cornerstone of biodiversity conservation efforts, will assume a decisive role in protecting freshwater species from the impacts of climate change. This study assessed the effects of climate change on migratory fish of the second largest neotropical river basin, evaluating the effectiveness of protected areas in safeguarding fish species, and hence the ecological functions that they perform and the ecosystem resources that they provide. The present range of 23 migratory fish of economic interest in the Paraná–Paraguay basin was estimated and the responses to future climatic shifts projected to the middle and end of the 21st century were examined, quantifying predictive uncertainties. Changes and losses of climatically suitable areas will trigger severe contractions in range, with the greatest impact on the most valuable species in commercial fishing, where range losses are likely to surpass 65% in the future. The main channel of the Upper Paraná River and tributaries of its left margin are projected to serve as climatic refuges for many species, and such regions are not affected by high predictive uncertainty. The results revealed that protected areas do not sufficiently protect migratory fish at present, and that they will continue to offer negligible protection in the face of climate change. This study alerts decision makers to the potential damage to inland fishery resources from climate change and provides useful information to guide conservation strategies spatially. We advocate that the creation of new protected areas and the redesign of the existing network to encompass regions that maximize current and future occupancy of migratory fish are crucial to conserve the valuable ecological, societal, and economic benefits that they provide.
Two sides of a coin: effects of climate change on the native and non-native distribution of Colossoma macropomum in South America
(2017-06) Lopes, Taise Miranda; Fernandes, Dayani Bailly; Almeida, Bia de Arruda; Santos, Natália Carneiro Lacerda dos; Gimenez, Barbara Carolina Garcia; Landgraf, Guilherme Okuda; Sales, Paulo César Lima; Ribeiro, Matheus de Souza Lima; Cassemiro, Fernanda Aparecida da Silva; Rangel, Thiago Fernando Lopes Valle de Britto; Diniz Filho, José Alexandre Felizola; Agostinho, Angelo Antonio; Gomes, Luiz Carlos
Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in ParanaÂ River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions.

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