Instituto de Pesquisas Cananéia

Abstract Mangroves are a critical coastal habitat that provides a suite of ecosystem services and supports livelihoods. We undertake the first global analysis to estimate density and abundance of 37 commercially important fish and invertebrates that are known to extensively use mangroves. Geomorphic mangrove type, sea surface salinity and temperature, and length of mangrove forest edge were important in predicting the density of commercial fish and invertebrates, with deltaic systems supporting the highest densities. The model predicted high densities throughout parts of southeast Asia, the northern coast of South America, the Red Sea, and the Caribbean and Central America. Application of our model onto the global mangrove extent, estimates that mangroves support the annual abundance of nearly 800 billion young-of-year fish and invertebrates contained in our model. Our results confirm the critical role of mangroves globally in supporting fish and fisheries, and further builds the case for their conservation and restoration.

Understanding environmental and anthropogenic variables that influence the presence of dolphins in coastal areas is fundamental for conservation planning and forecasting. In this study, we applied generalized additive models to identify areas of high probability of occurrence of Guiana dolphins in Mucuripe embayment, a heavily urbanized area in northeastern Brazil. Sighting and effort data were collected during systematic, boat-based surveys between 2009 and 2011. Models were built using 70% of the data to test the model and 30% to evaluate its predictive performance. Variables investigated included depth, slope, seabed complexity, and distance to the coast, breakwaters, and the fishing grounds. The best model explained 40.8% of the total deviance. Seabed complexity, distance to the breakwaters and distance to the fishing grounds were the most important variables, with dolphins showing a preference for areas with a less complex seabed immediately adjacent to the breakwaters (<500 m, decreasing with distance) as well as a preference for fishing grounds (again decreasing with distance). Using the validation data, the model showed excellent performance. The habitat use and preference of Guiana dolphins in the study area seem to be mainly influenced by foraging opportunities, with dolphins concentrating in areas with higher prey abundance and where foraging success is higher because of a strategy called ‘barrier-feeding’, in which animals herd fish against piers, breakwaters, and the coast.

The compositions of bacterial communities and populations during aerobic stabilization of livestock manure have been investigated, focusing on how the aging of feedstock affected the bacterial diversity of the composting mass.The livestock manure was divided into two groups -aged and fresh, and then used to prepare the feedstock with additives.Composting experiments were carried out for 15 days using a pilot-scale batch reactor with vacuum-induced aeration.Two different aeration rates were applied to the batch reactor, and their effectiveness was evaluated.Changes in total heterotrophic bacteria count and moisture content were monitored.The associated changes in bacterial community compositions were characterized using 16S ribosomal ribonucleic acid (rRNA) gene sequencing.The Firmicutes in the fresh manure decreased from 48 to 13% for the first ten days, and the dominant phylum shifted to the Proteobacteria (29%), Bacteroidetes (23%), Actinobacteria (20%), and others (15%).Under the given conditions, the use of relatively fresh manure was essential to preserve the diverse bacterial populations in the feedstock and enhance the bacterial diversity during aerobic stabilization.More research should be performed to investigate the degradability of emerging contaminants (e.g., antibiotics) in livestock manure using an engineered composting system providing well-controlled environmental conditions.

Abstract This study used models to assess how the type of prey caught by artisanal fishermen influenced the occurrence of Guiana dolphins (Sotalia guianensis) in the region of the estuarine lagunar comple.x of Cananéia (São Paulo, Brazil). The data were collected from January 2012 to November 2014, during three fieldwork expeditions per season (spring, summer, autumn, winter). Mullets (Mugil liza) were the fish with the highest association to dolphins, followed by Oligoplites spp. and Lobotes spp.; Mugil curema and shrimp, on the other hand, negatively influenced their distribution. The presence of fish‐weir fisheries in the estuary also had a positive influence on the occurrence of dolphins, since this fishing gear is used as a barrier, minimizing the potential for their prey to escape.

Terrestrial animals are negatively affected by habitat loss, which is assessed on a landscape scale, whereas secondary effects of habitat loss, such as crowding, are usually disregarded. Such impacts are inherently hard to address and poorly understood, and there is a growing concern that they could have dire consequences. We sampled birds throughout a deforestation process to assess crowding stress in an adjacent habitat remnant in the southern Brazilian Atlantic Forest. Crowding is expected of highly mobile taxa, especially given the microhabitat heterogeneity of Neotropical forests, and we hypothesized that the arrival of new individuals or species in refuges shifts assemblage patterns. We used point counts to obtain bird abundances in a before-after-control-impact design sampling of a deforestation event. Temporal changes in taxonomic and functional diversity were examined with metrics used to assess alpha and beta diversity, turnover of taxonomic and functional similarity, and taxonomic and functional composition. Over time increased abundance of some species altered the Simpson index and affected the abundance-distribution of traits in the habitat remnant. Taxonomic composition and functional composition changed in the remnant, and thus bird assemblages changed over time. Taxonomic and functional metrics indicated that fugitives affected resident assemblages in refuges, and effects endured >2 years after the deforestation processes had ceased. Dissimilarity of taxonomic composition between pre- and postdeforestation assemblages increased, whereas functional composition reverted to preimpact conditions. We found that ecological disruptions resulted from crowding and escalated into disruptions of species' assemblages and potentially compromising ecosystem functioning. It is important to consider crowding effects of highly mobile taxa during impact assessments, especially in large-scale infrastructure projects that may affect larger areas than is assumed.

An extended period of parental care is fundamental for survival of cetacean offspring. Although qualitative descriptions of parental care and mother-calf spatial relationships are available for several species, studies using a quantitative approach throughout development of offspring are scarce. Here, we analyzed how strategies of parental care occur during the ontogeny of the Guiana dolphin, Sotalia guianensis, in the Cananeia estuarine system, Sao Paulo, Brazil. We tested the hypothesis that both the strategy and frequency of parental care vary according to the development of the offspring and assessed whether such changes are associated with the life stage of the calves. The frequency of parental care did not decrease according to the age of the calves. However, parental care strategies directed at infants were more diversified than those directed at neonates and juveniles. Increasing maternal-calf separation can expose older calves to new and risky situations and may demand different strategies of care. We conclude that there is a shift in the strategy adopted by the S. guianensis mothers according to the requirements of each age class, with parental care being dispensed until calves become fully independent.

The domestic cat (Felis silvestris catus) is indicated as a threat to several native species in different regions where they occur, especially seabirds in insular environments.In this study, we present the results obtained through fecal analysis and identification of the remains of prey killed by domestic cats in a fishing village in an insular area of the Brazilian Atlantic Forest.Although several species of seabirds use the island either as a migratory route, residence, or for nesting, we did not detect their presence among the identified items.However, other species of birds, mainly Passeriformes, were found.This corresponded to less than 10% of the total of items identified as predated by domestic cats during the sampling period.We emphasize the importance of carrying out new studies, as well as evaluating measures to identify more sensitive species and preventing potential impacts caused by felines in forest remnants in Neotropical regions.