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Integrated multi-trophic aquaculture has been considered as an alternative for the sustainable development of mariculture. This study evaluated the use of a multi-trophic system in mariculture in order to improve economic viability indices and reduce environmental impacts, leading to a sustainable production. To do so, the economic indicators of two monotrophic crops were considered: Perna perna mussels and Rachycentron canadum cobias, along with a multi-trophic system involving both species. The indices for the evaluation of profitability were the internal rate of return (IRR), the payback period (PP) and the net present value (NPV). Investment analyses were realized through cash flow and determination of economic viability indicators for a period of 10 years. The systems were evaluated in different scenarios. Each scenario was estimated by means of 20% and 40% variations of the values adopted for the following parameters: unit price of cobia juveniles, average price of the feed, cobia commercial price, mussel commercial price, cobia productivity, and mussel productivity. The multi-trophic system showed greater economic viability in the different scenarios evaluated. This system demonstrated greater resilience, which is more economically attractive to an entrepreneur. Production diversification is an alternative option with a lower associated investment, which can favor economic return and mitigate the risks of small-scale systems dedicated to monocultures.

The choice of suitable substrates has received special attention in aquaculture and fishkeeping ventures. The aim of this study was to evaluate the influence of different substrates on water quality and the development of lambari fish (Astyanax bimaculatus) and freshwater shrimp (Macrobrachium potiuna). Two experiments were performed sequentially, one with fish and the other with shrimp. In both experiments, three different substrates were evaluated (shell gravel, river gravel, and dolomite), and the control was without any substrate. The water parameters evaluated were as follows: dissolved oxygen, saturation, oxide-reduction potential, temperature, pH, alkalinity, conductivity, ammonia, nitrite, nitrate, and phosphorus. It was observed that both dolomite and shell gravel interfered with the parameters that are related to the acid-base balance of the water and the availability of calcium and magnesium. The productive performance of lambari fish was not affected considering the different substrates evaluated; however, the productive performance of freshwater shrimp was lower in the absence of substrates in relation to the other treatments.

Salt‐water recirculation systems using automatic feeders are a new frontier for marine aquaculture. The definition of the feed frequency is fundamental for the correct use of automatic feeders. Different feeding frequencies (1, 3, 6, 12 and 18 times a day) using automatic feeders were evaluated in two experiments on the performance of the dusky grouper (Epinephelus marginatus) in salt‐water recirculation system. In the first experiment, three feeding frequencies were evaluated: feeding once a day; three times a day and six times a day. In the second experiment, three feeding frequencies were evaluated: feeding six times a day; 12 times a day and 18 times a day. Waters parameters (temperature, salinity, oxygen level, total ammonia, pH and oxidation‐reduction potential) were maintained at specific ranges for the species. Among all the evaluated frequencies, 12 times a day provided the best productive performance, obtaining superior results for final weight, final biomass, specific growth rate and daily weight gain. For juveniles of the dusky grouper, the ideal feeding frequency is regular feedings every 2 hours, which is impractical to run without the use of automatic feeders.

According to apparent competition theory, the co-occurrence of two species that share the same predators appears to affect each other's population growth and abundance. However, due to habitat loss and over-hunting, top predators are being made rare worldwide. Considering that apparent competitors share similar resources, we would expect the absence of top predators to reflect in changes on prey realized trophic niches. To test our hypothesis, we developed a model to predict the abundance ratio of apparent competitor species based on changes in their realized trophic niches. We tested our model against field data on the Neotropical marsupials Didelphis aurita and Metachirus nudicaudatus. Our results revealed that D. aurita and M. nudicaudatus are two species under apparent competition and their realized trophic niche and diet overlap change according to the presence of top predators. The model was able to predict the actual relative abundances of D. aurita and M. nudicaudatus in the three empirical studies analyzed. Our study presents quantitative support to the apparent competition theory; however, the model's applications to other groups still need to be verified. Additionally, our study shows that the lack of top predators has consequences on the realized trophic niche of their prey, and therefore, we reinforce that conservation plans need to focus on the effects of top predator loss on ecosystems.

Due to the decline of fishing stocks, aquaculture has been expanding throughout the world. Taking into account the possibility of conflicts of aquacultural activities in areas of environmental protection, this study aims at assessing the effects of mariculture upon the local ichthyofauna of Itaguá Bay in Ubatuba, São Paulo state, Brazil, which is within a marine protection area. In order to do so, the fish community was analyzed in areas with mussels and macroalgae farms and in areas without any maricultural activities. After six months of sampling efforts, 230 individuals were captured from 19 different species and 15 families. There was no difference in catchability, richness, diversity, and evenness among the areas. Nevertheless, the species composition was distinct in areas where mussels were farmed. These areas have presented twice as much fish biomass than the others. Based on these results, we can observe that the environmental alterations caused by mussel farming, are sources of habitat complexity, hence able to enrich the marine fauna of the region. Thus, we conclude that mariculture, specifically mussel farming, has a positive impact on ichthyofauna, contributing to biodiversity maintenance in protected areas.

O enriquecimento ambiental pode ser uma ferramenta importante para melhorar o desempenho produtivo da garoupa-verdadeira Epinephelus marginatus (Lowe, 1834). O objetivo deste estudo foi avaliar a preferencia por abrigos e o efeito da disponibilidade de abrigos sobre o desempenho produtivo de juvenis de garoupa-verdadeira em sistema de recirculacao de agua salgada. Foram realizados dois ensaios, o primeiro para determinar a preferencia por diferentes tipos de abrigos (pedras, tijolos e tubos de PVC de diferentes cores) e o segundo sobre o uso de abrigos, com tres tratamentos (T1 = sem abrigo; T2 = um abrigo por peixe e T3 = dois abrigos por peixe). A garoupaverdadeira mostrou preferencia por abrigos de tubos de PVC de cor marrom. O uso de abrigos favoreceu um melhor desempenho produtivo da especie em sistemas de recirculacao de agua salgada.

Species coexistence depends mainly on the spatiotemporal distribution of resources, and, in extreme cases, results in direct competition (interference). In the present study, we report for the first time an agonistic interaction between marsupials and bats, and food defense behaviour in the black-eared opossum Didelphis aurita. We describe the agonistic interaction between the opossum and a bat of the species Artibeus lituratus while they foraged on the same infructescences of Cecropia glaziovii and C. hololeuca in an Atlantic Forest area. While competing for food, the bats foraged in group (of approximately six individuals) and apparently showed a synchronized and coordinated behaviour to pick the infructescences. Then, a male D. aurita showed an aggressive behaviour toward the bats, moving on branches and leaf petioles and vocalizing to the bats, apparently trying to scare them away. We conclude that D. aurita defends food in a way consistent with the concept of economic defendability. We know little about how Neotropical mammals share resources in time and space, so future studies on the foraging behaviour of the black-eared opossum should focus on agonistic interaction with competitive species.

Dung beetles feed and nest in mammal feces, are influenced by habitat quality and have limited dispersal ability. We hypothesized that dung beetle community structure is affected by mammal composition, habitat structure, and spatial distance, and that these predictors vary among the functional groups in communities. Dung beetles and mammals were sampled using pitfall traps and camera traps, respectively, at 15 Atlantic Forest sites between 2005 and 2013. Habitat structure was described using the point-quadrant method. We utilized descriptive ecological values and used variation partitioning to identify predictors of dung beetle community composition both as a whole, and after organizing the community into functional groups. We recorded 43 dung beetle species and 28 mammal species. Mammal and dung beetle species richness were positively correlated. Mammals and habitat explained the majority of the variation among dung beetle communities, and explanatory values varied substantially when using the functional group approach. Our results indicate that mammals are, indeed, important drivers of dung beetle community structure. Individually, or in combination with habitat structure, mammal composition explained 40 % of the total variation in dung beetle data, i.e., the abundance and species composition of dung beetles and mammals covary. However, herbivorous mammals, medium-sized mammals and omnivorous mammals numerically contributed more than did other groups to the explanation of variation in dung beetle guilds. Habitat structure was an important determinant for dung beetle functional group abundance, and spatial distance influenced covariation between dung beetles and mammals. Thus, the integrity and maintenance of ecological processes in the Atlantic Forest may be dependent on these groups, and further fragmentation, habitat loss and defaunation may increase the sensitivity of this already reduced and threatened biome.

Biofouling is one of the biggest challenges for mariculture in tropical waters. This study aims to evaluate different materials in control to biofouling in tropical waters through two experiments. For Experiment I, compared the accumulation of biofouling on different nylon panels and the use of antifouling (copper-base) paint that remained submerged for 8 weeks. In experiment II, evaluated multifilament nylon, monofilament nylon and copper alloy metal with and without the use of zinc anode. The experiment were carried for 150 days, in summer with water temperature of 26 °C. Significant biomass of biofouling was observed on nylon meshs, and those of monofilaments presented a lesser amount of diversity of organisms compared to the multifilament. The multifilament mesh painted with copper-based paint proved to be efficient in controlling biofouling. The copper alloy metal was maintained without the accumulation of biofouling throughout the experimental period (150 days). No differences were observed for copper alloy metal with or without a zinc anode. Copper alloy metal was effective as an antifouling agent even in a tropical waters. This data can open the way for a new system of fish farming in tropical seas using copper alloy metal for the construction of net cages.

Industrial fish processing generates a significant amount of wastes, which are high-value nutritional by product. Therefore, the use of fish residues could be a sustainable practice for fattening marine finfishes. In the present study, we have evaluated the benefits of feeding cobia juveniles with three different diets based on residues of salted sardine: (i) formulated with acid silage of salted sardine residue; (ii) formulated with salted residue combined with an acidity regulator; and (iii) pure salted sardine residue. Fishes that were feed with pure salted sardine residue had significant body weight gain and also expressed a lower feed conversion rate. Fishes feed with the other two diets presented a similarly lower zootechnic performance. Also, no significant changes indicating a harmful effect of salted sardine residue for cobia feed were observed in the digestive tract of any the fishes. However, the diet based only on salted sardine residue showed higher organosomatic indexes. That can be attributed to the rich lipid and fatty acid contents of pure residue and it can be an indicative that silage processing was unable to provide the same amount of fatty acids, as pure residue diet did. In conclusion, our results indicate that pure salted sardine residue was the best choice of feed for the cobia. The use of salted sardine residue as diet complementation should be further evaluated, since its use can improve aquaculture development as an instrument of fishery resources conservation.

The objective of this work was to evaluate different feeding rates on the productive performance of cobia (Rachycentron canadum) grown in brackish waters. For the experiment, 1,600 juveniles were distributed in 16 enclosures installed in an estuarine pond. Four different feeding rates were evaluated: 1, 3, 5, and 7% live weight (LW) per day. The following performance parameters were assessed: survival, final biomass, specific growth rate, daily weight gain, apparent feed conversion, protein efficiency rate, lipid efficiency rate, and hepatosomatic index. Survival was greater than 80% at all feeding rates. The most efficient feed conversion rate was obtained with the feeding rate of 5% LW per day, which also resulted in better values for the hepatosomatic index. The rate of 5% LW per day provides a better productive performance for cobia in brackish waters. Resumo: O objetivo deste trabalho foi avaliar diferentes taxas de arraçoamento no desempenho produtivo de bijupirá (Rachycentron canadum) criado em águas salobras. Para o experimento, 1.600 juvenis foram distribuídos em 16 cercados instalados em viveiro, em área estuarina. Foram avaliados quatro diferentes níveis de arraçoamento: 1, 3, 5 e 7% do peso vivo (PV) por dia. Avaliaram-se os seguintes parâmetros de desempenho: sobrevivência, biomassa final, taxa de crescimento específico, ganho de peso diário, conversão alimentar aparente, taxa de eficiência proteica, taxa de eficiência lipídica e índice hepatossomático. A sobrevivência foi superior a 80% em todos os níveis de arraçoamento. A conversão alimentar aparente mais eficiente foi obtida com a taxa de arraçoamento de 5% do PV por dia, que também resultou em melhores valores para o índice hepatossomático. A taxa de 5% do PV por dia proporciona melhor desempenho produtivo para o bijupirá em águas salobras.

Wild animals have been kept as pets for centuries, in Brazil companionship is one of the main reasons why wild species are legally bred and traded. This paper is an attempt to call the attention for problems concerning the welfare of wild pets involved in the trading system in Brazil. Some issues presented are: a) the significant increase in the number of wildlife breeders and traders and the difficulties faced by of the Brazilian government in controlling this activity; b) the main welfare issues faced by breeders and owners of wild pets; and c) the destination of wild pets no longer wanted. Finally, some recommendations are made having the welfare of the animals as a priority.

Species co-existence depends on how organisms utilize their environment and resources. When two sympatric species are similar in some ecological requirements, their coexistence may arise from differences in resource use over time and/or space. Interactions among coexisting marsupials remain poorly understood, especially in the Neotropics. Here we combine spatial niche measurements, individual-resource networks, and isotopic niche approaches, to investigate the ecological strategies used by the Neotropical marsupials Didelphis aurita and Metachirus nudicaudatus to co-occur in an area of Serra do Mar State Park (southeast of Brazil). Both individual-resource networks and isotopic niche approaches indicate similar patterns of omnivory for both species. Isotopic analysis showed the species' trophic niche to be similar, with 52% of overlap, and no differences between proportional contributions of each resource to their diets. Moreover, individual-resource network analysis found no evidence of diet nestedness or segregation. The trophic niche overlap observed was associated with spatial segregation between species. Despite using the same area over the year, D. aurita and M. nudicaudatus exhibited spatial segregation among seasons. These results illustrate that the detection of spatial segregation is scale-dependent and must be carefully considered. In conclusion, our findings provide a new perspective on the ecology of these two Neotropical marsupials by illustrating how the association of distinct but complementary methods can be applied to reach a more complete understanding of resource partitioning and species coexistence.

SummarySolitary TinamouTinamus solitariusis a threatened Brazilian bird, and very little is known about its ecology and behaviour. In this study we aimed to verify the use of habitats in different stages of plant succession and the circadian activity pattern of the species. The study was conducted in Santa Catarina state (27º43’S, 48º49’W). Six camera traps were used to record the species in three areas of different successional stages during a 12-month period. Traps remained at each sample site for two months, after which they were moved to a new site, a minimum distance of 100 m apart. A total of 76 independent records of Solitary Tinamou were obtained, and its habitat use was found to be different within the three successional stages (P= 0.02). The majority of 54 independent records were obtained in the secondary forest; not one photo of the species was taken in the most degraded area. Solitary Tinamou exhibited a crepuscular pattern of activity, with most records (n= 38) taken at 07h00 and 06h00, and it appears to be sensitive to forest clearance.

O Parque Estadual da Serra do Tabuleiro, situado no centro-leste do Estado de Santa Catarina, sul do Brasil, possui 85.000ha e abrange grande diversidade de ambientes (floresta ombrófila densa, incluindo manguezais e restingas, floresta ombrófila mista e estepe ombrófila). De 1991 a 2010 foram realizados 22 estudos sobre sua mastofauna, abrangendo os métodos de captura com armadilhas de arame, armadilhas de interceptação e queda, caixas de nidificação, redes-de-neblina, armadilhas fotográficas, observação direta e vestígios. Foram registradas 75 espécies autóctones (cerca de 54% das espécies de mamíferos terrestres confirmados para Santa Catarina) pertencentes a 8 ordens e 25 famílias. Quinze espécies são ameaçadas em nível estadual, nacional ou mundial. A possibilidade de ocorrência de outras espécies e aspectos gerais da conservação dos mamíferos no Parque são discutidos.

The first and only study on gastrointestinal parasites of wild rodents in the Island of Santa Catarina was done in 1987. The aim of this study was to identify intestinal parasites from wild rodents in Santo Amaro da Imperatriz and Santa Catariana Island, and to compare the richness and composition of the gastrointestinal parasite community of both areas. Rodents were captured with live traps, and feces were screened using the sedimentation method and optical microscopy. The following species of rodents were captured in the two areas: Akodon montensis, Euryoryzomys russatus, Oligoryzomys nigripes and Nectomys squamipes. In Santo Amaro da Impetratriz, prevalent parasites were: A. montensis (51%), E. russatus (62%), O. nigripes (53%) and N. squamipes (20%). From the Island of Santa Catarina the rodent prevalence rates were: A. montensis (43%), E. russatus (59%), O. nigripes (30%) and N. squamipes (33%) and the collected parasites were: Hymenolepis sp., Longistriata sp., Strongyloides sp., Hassalstrongylus sp., Syphacia sp., Trichomonas sp., Ancylostomidae, Trichuridae, Oxyuridae and Eucoccidiorida. The species richness (10.6 ± 0.7) of the endoparasite comunity in the area located on the continent was higher (p < 0.01) and different (p = 0.001) from that of the area located on the island (6.9 ± 0.5).

The wildlife trade is becoming increasingly more relevant in discussions concerning conservation biology and the sustainable management of natural resources. The aim of this study was to document the trade and breeding of wildlife in Santa Catarina state, in southern Brazil. Data was collected from annual reports (1996-2008) of wildlife breeders which were sent to IBAMA. By the end of 2008, there were 79 wildlife breeders and 11 wildlife traders distributed in Santa Catarina. Commercial breeding accounted for the highest number of breeders (51%). In total, there are 213 species of wild animals bred in the state: 177 birds, 19 mammals and 17 reptiles. Of these, 48% are native to Santa Catarina, 32% occur in other Brazilian states and 20% are exotic to Brazil. Nine percent of the species bred are vulnerable or endangered. It was observed that some breeders reported breeding unauthorized species. Altogether, 93 species are bred illegally by 19 breeders. Of these species, 48 are native to Santa Catarina and three are classified as vulnerable or in danger of extinction. We hope the data presented in this paper contributes to the development of conservation strategies and conscious use of wildlife resources in Brazil.