Fabio Cop Ferreira

Assessing the importance of the riparian zone for stream fish communities in a sugarcane dominated landscape (Piracicaba River Basin, Southeast Brazil)

In the Neotropics, the effect of agriculture on freshwater habitats is still poorly understood, particularly with respect to sugarcane expansion to meet increased ethanol demands. The variation in taxonomic composition, community attributes and trophic structure of fish assemblages from streams under different riparian zone preservation conditions were studied. Nine stream reaches under the following riparian vegetation conditions were selected: Native Forest (NF), with mostly primary forest; Secondary Forest (SF), which included sites with vegetation in an advanced stage of regeneration surrounded by sugarcane plantations; and Sugarcane sites (SC), located in areas without riparian vegetation, adjacent to sugarcane crops. Forty-one species were collected. The variance partitioning and partial Redundancy Analysis (pRDA) indicated that community composition and trophic structure were significantly explained by riparian condition and spatial variations, while diversity, richness, abundance and biomass were only explained by season and space, with higher diversity and richness at the SF sites. Abundance-Biomass curves (ABC curves) suggested that sugarcane plantations destabilized fish assemblages, especially at the more intensively managed sites, which seem to influence stream integrity and associated fish fauna. We concluded that both physical conditions of streams and some attributes of fish communities reflected the different levels of preservation of the riparian buffers, but given the influence of regional processes which have a pervasive role in shaping local assemblages, land use at the watershed scale seemed to be important especially to explain the higher richness and diversity found at the SF sites.

Headwater stream fish fauna from the Upper Paranapanema River basin

The Parana River basin has about 600 fish species. In the Upper Parana, 310 fish species were recorded, with 52 species were registered in the streams and headwaters of the Paranapanema River. The aim of this study was to characterize the stream fish communities in the Upper Paranapanema River basin. Samplings were conducted with electrofishing during the dry season in the year of 2014. The collection effort consisted of 30 streams stretches. As a result, 41 species of stream fish were recorded in the Upper Paranapanema River basin, distributed in 26 genera, 11 families and 7 orders. Thirty-nine percent of the species can be considered rare, 41% intermediate and 20% common. We captured approximately eight species by stream stretch and the estimated richness (Schao2) was 40 ± 6 species. Around 40% of the individuals had less than 50 mm in length.

Feeding and reproductive patterns of Astyanax intermedius in a headwater stream of Atlantic Rainforest

In this paper, we determined diet composition, reproductive periodicity and fecundity of Astyanax intermedius in a headwater stream of a State Park of an Atlantic rainforest. We also evaluated the influence of rainfall, water temperature and fish size on niche width and niche overlap. Sampling was conducted monthly throughout one year in the Ribeirão Grande stream, southeastern Brazil. Diet consisted of 31 food items with equal contribution of allochthonous and autochthonous items. Females were larger than males, and the mean sizes at first maturation were 4.44 cm and 3.92 cm, respectively. Based on 212 pairs of mature ovaries, the number of oocytes per female ranged from 538 to 6,727 (mean = 2,688.7). Niche width and niche overlap were not related to rainfall nor water temperature and only niche width increased with fish size, suggesting that as fish grow, more items are included in diet. Our results suggested that A. intermedius fit as a typical opportunistic strategist which may explain the prevalence of this species in several isolated headwater basins of vegetated Atlantic forested streams where food resources are abundant and distributed throughout the year.

Anuran Communities in Different Riparian Habitats: Native Forest, Secondary Forest, and Sugarcane

Abstract. This study aimed to test the influence of different riparian habitats on the structure of anuran communities in southeastern Brazil. Nine stream stretches were selected representing three different riparian habitat types: Native Forest, Secondary Forest, and Sugarcane. A total of 223 individuals of 17 species and five families were captured. The Chao1 richness index indicated that after standardizing the sampling effort the Native Forest sites had higher richness than the Secondary Forests and Sugarcane sites, which presented similar richness. The Abundance and Biomass Curves for the Native Forest sites showed an overlap of the weight and abundance curves, suggesting that these sites presented lower disturbance levels. A disturbance gradient from Native Forest towards Sugarcane sites was observed. The Bray-Curtis similarity index showed a significant effect of riparian condition on species composition. Our results suggest that Sugarcane and Secondary Forest sites limit the distribution of certain species, such as those from the family Hylidae species related to litterfall, and enable colonization by open-habitat species that are capable of resisting anthropic pressure.

Presence of riparian vegetation increases biotic condition of fish assemblages in two Brazilian reservoirs

Abstract The riparian vegetation in lakes and reservoirs is source of course wood structures such as trunks and branches and is used as sheltering, spawning and foraging habitats for fishes. The reduction of these submerged structures can thus, affect the composition and structure of fish assemblages in reservoirs. Aim To evaluate the influence of riparian vegetation on the biotic condition of fish assemblage by adapting the Reservoir Fish Assemblage Index (RFAI) to two reservoirs in the Upper Paranapanema river basin, Sao Paulo State, Brazil. Methods The RFAI was adapted from metrics related to the functional characteristics and composition of fish assemblages through a protocol of metric selection and validation, and to its response to the presence of riparian vegetation. Results The final RFAI was composed by nine metrics, been lower in sites without riparian vegetation as consequence of the predominance of larger individuals and the percent of piscivorous and detritivorous fishes. Conclusions These results suggest that increasing shore habitat complexity in reservoirs by maintaining riparian vegetation increases fish biotic integrity.

The protected areas system in Brazil as a baseline condition for wetlands management and fish conservancy: the example of the Pantanal National Park

E iminente que o Brasil desenvolva ferramentas para monitorar o sistema de areas protegidas do pais, formado especialmente pelas Unidades de Conservacao e tendo como foco a protecao efetiva da biodiversidade. Nesse contexto, esse trabalho discute metricas de referencia (ou linhas de base) para compor um Indice de Integridade Biotica (IIB) baseado nas comunidades de peixes, tendo como area de estudo o Parque Nacional do Pantanal Matogrossense. Os habitats encontrados no Parque foram agrupados em quatro estratos ambientais: rios, corixos (cursos d´agua que se conectam a planicie de inundacao) e baias permanentes e temporarias. As coletas de peixes foram realizadas em 12 pontos amostrais durante o periodo seco (out/nov de 2010 e 2011). Foram identificadas 146 especies de peixes, totalizando 18.954 exemplares coletados em amostragens padronizadas. Nao houve associacao entre a estrutura da comunidade e os estratos ambientais, sugerindo homogeneidade de habitats. O IIB final foi composto por nove metricas, a maior parte alocada na classe excelente de integridade biotica, poucas na classe regular e nenhuma na classe pobre. Nao houve diferenca significativa no IIB entre os dois anos consecutivos. Esses resultados oferecem subsidios tecnicos para a tomada de decisao sobre a gestao das areas alagaveis no Pantanal brasileiro.

Fish-based Index of Biotic Integrity for wadeable streams from Atlantic Forest of south São Paulo State, Brazil

Understanding the relationship between environmental quality of streams and biological integrity of fish assemblages is critical to successful ecosystem management. Aim We adapted the Index of Biotic Integrity (IBI) using ecological data of the fish assemblages that occur in headwater streams from the Atlantic Forest in southern Sao Paulo State. Methods We sampled the ichthyofauna and collected environmental data in 27 streams stretches during the dry season of 2010. The fish species were categorized into trophic group, position in the water column and preference for rapid meso-habitats. Candidate metrics were screened for range, responsiveness and redundancy. Results Of the 17 metrics tested, four metrics were included in the IBI. They belonged to attributes species diversity: percentage of individuals as Loricariidae family; habitat use: percentage of individuals as benthic riffles; and trophic function: percentage of individuals as omnivores and percentage of individuals as herbivores/detritivores. Eight streams (30%) were classified as excellent or good and fourteen (50%) as poor or very poor. Conclusions On a regional scale, many aspects of biological integrity were altered but there are streams that can be used as biological reference.

Landscape effects on the occurrence of ichthyofauna in first-order streams of southeastern Brazil

Objective In this study we aimed to understand how extrinsic environmental factors measured in the watercourses and the surrounding landscape influence the ichthyofauna of first-order streams. Methods Data were collected within the Corumbatai River Basin, Sao Paulo, southeastern Brazil, during the dry season of 2012. We sampled the ichthyofauna in 13 stretches of streams distributed across four river sub-basins. The stretches differed in relation to the presence/absence of riparian forest, the predominant type of matrix and the percentage of forest. Response variables were species richness and the occurrence of functional groups and explanatory variables include both local and landscape structures from the surrounding environment. Local variables comprised the following water quality and structural attributes: pH, temperature, conductivity, turbidity, flow rate, depth, width, type of substrate. Landscape variables included presence/absence of riparian vegetation, type of vegetation, type of matrix, percentage of forest and canopy cover. Results A total of 268 individuals were recorded, which were distributed among 12 species. The landscape structure influenced the occurrence of functional groups in first-order streams, especially allochthonous-feeders, nektonic and hypoxia-intolerant species. The presence of riparian forest was the most important predictor. Species richness was negatively related to the presence of riparian vegetation, supporting the hypothesis that degraded landscapes lead to a reduction in diversity. Conclusion The protection of riparian vegetation is critical to the maintenance of ichthyofauna diversity in first-order streams. The presence or absence of riparian vegetation differently affected the occurrence of species depending on their functional characteristics, particularly those related to the tolerance to hypoxia, source of alimentary items and the position in the water column.