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In a natural context, many avian species exhibit the ability to assess and balance factors such as food availability, food quality, and energy expenditure when making foraging decisions. However, avian behaviours can also diverge from the predictions, influenced by a range of variables, including social behaviours, predation pressures, and individual personalities. Chilean flamingos, popular social birds native to South America, remain relatively underexplored in terms of their foraging ecology and the interplay between environmental conditions and foraging behaviours, especially within the context of conservation. To address this knowledge gap, we conducted a comprehensive study, collecting monthly physical and biological data from foraging flocks of Chilean flamingos at Lagoa do Peixe National Park, a vital contra-nuptial site located in southern Brazil, spanning from October 2021 to September 2022. We employed Generalized Linear Mixed Models to establish correlations between this dataset and the relative frequency and duration of four identified foraging behaviours: Pecking up, Head-dipping, Feet-trembling, and Dredging. Our findings substantiate that the foraging patterns exhibited by Chilean flamingos in this region are intricately linked to the trade-off between energy expenditure and the rewards obtained, primarily influenced by factors such as lagoon depth and the availability of food resources. Moreover, our results unveil a parabolic pattern in the distances maintained between individual flamingos in the flock, potentially attributed to facilitate foraging dynamics within larger groups, despite the concurrent increase in aggressive interactions. In summary, our study underscores the multifaceted variables that influence the foraging strategies of Chilean flamingos in a significant contra-nuptial area in southern Brazil. It sheds light on the behavioural adaptability of these birds and underscores the potential repercussions of this dynamic on individual and population performance and fitness. • Water depth, food type and food availability are the main variables influencing the foraging behaviors of Chilean flamingo in a natural environment; • There are a trade-off between energetic reward and energetic expenditure while performing different foraging behaviors; • The intra-flock distance also influence the foraging behaviors characteristics, with a balance between intraspecific competition and foraging facilitation; [ABSTRACT FROM AUTHOR]

The discretion of public agents has been gaining importance as an object of study because it is a relevant issue in the management and implementation of policies. Public servants face discretionary decisions in various ways, ranging from the construction of creative ways to generate good social impacts to, at the extreme limit, inaction for fear of subsequent blame for conduct considered improper. This study sought to understand how the experience of discretionary public servants in management careers takes place and their dilemmas. Qualitative research was carried out with specialists in public policies from the state of São Paulo and government managers from the state of Pernambuco. Field research included data collection through 5 focus groups and content analysis. The results show that the main dilemma faced by bureaucrats refers to decision-making based on their competence and current knowledge or inaction for fear of punishment if the decision is judged as illegal or in bad faith. Consequently, there is the so-called "apagão das canetas," i.e., a decision paralysis. There is a constant trade-off between discretion and blame, and public servants develop strategies to mitigate the risks of being sanctioned. [ABSTRACT FROM AUTHOR]

Habitats with spatial variation in food availability, predation risk, and hunting pressure allow us to study how animals resolve the trade‐off between food searching and predator avoidance. We investigated the influence of food availability, predation risk, and the perceived predation risk on habitat use by a primate living under high hunting pressure, the yellow‐breasted capuchin monkeys, Sapajus xanthosternos, at Una Biological Reserve (ReBio Una). We hypothesized that the hunting pressure occurring in the capuchins' home range would favor predator avoidance to the detriment of searching for food. We characterized a set of covariates related to resource availability (fruit and invertebrate biomasses, feeding on dispersed and clumped food items, sleeping sites), perceived predation risk (alarm calls given to terrestrial and aerial predators, silent group movement, and vigilance behavior), and actual predation risk (evidence of hunting) and estimated their effects on how one group of capuchin monkeys uses its habitat. The group divides its time among three major forest types within their home range: agroforest, mature, and secondary. Our results suggest that the actual and perceived risk of hunting by humans, as well as the perceived predation risk by both terrestrial and aerial predators, were significant determinants of capuchin monkeys' space use. Yellow‐breasted capuchin monkeys' space use was negatively related to the risk of hunting by humans (actual evidence and silent behavior), the perceived risk of predation by both aerial and terrestrial predators, and the presence of sleeping sites. Capuchin monkeys' use of space was not related to the biomass of fruits in the habitat, and the biomass of invertebrates had a very low positive effect. We confirmed our prediction that in a habitat with high hunting pressure, the risk of predation, both perceived and actual, had a more significant impact on how yellow‐breasted capuchins used space than did food availability. Research Highlights: Hunting by humans increases the perceived risk of predation by capuchins.Landscape of fear, mainly of hunting, affected the habitat use by capuchins.Habitat choices were influenced more by perceived predation risk than by food availability. [ABSTRACT FROM AUTHOR]

Context: Land use and land cover (LULC) changes may affect the provision of ecosystem services. However, little is known how LULC changes influence the spatio-temporal variation in ecosystem service and their interactions along altitudinal gradients. Objectives: Here we assessed the spatio-temporal variation of eight ecosystem services in an altitudinal gradient between the year of 1986 and 2015, and quantified the effect of LULC transitions on the provision and interactions of ecosystems services. Methods: We modelled and mapped eight ecosystem services in an altitudinal gradient characterized by low (< 600 m), middle (600–1200) and high altitudes (> 1200) in Zona da Mata, Minas Gerais state, Brazil. We quantified changes in ecosystem services by contrasting ecosystem service maps between 1986 and 2015, and explored how four common LULC transitions affected the variation and the interactions between the eight ecosystem services. Results: The spatio-temporal analysis indicated that six out of eight ecosystem services increased from 1986 to 2015, while soil erosion control and water flow regulation decreased. In areas above 1200 m, regulating services dominated, while in areas below 1200 m provisioning service were most evidenced. LULC transitions from forest to agricultural areas, and vice versa, resulted in trade-offs between provisioning and regulating ecosystem services. Conclusions: LULC changes drive the spatio-temporal variation of ecosystem services along an altitudinal gradient with contrasting biophysical conditions. Future management of ecosystem services in the landscapes should take into the account the biophysical conditions and the consequences of specific LULC transitions. [ABSTRACT FROM AUTHOR]

Non-indigenous fouling species (NIS) often dominate coastal facilities, such as harbors and marinas. Along the subtropical Coast of Brazil, sessile communities from artificial habitats are mostly dominated by the NIS ascidian Didemnum perlucidum and the bryozoan Schizoporella errata, which show contrasting life-history traits. To understand the dynamics between these species and better predict the identity of the dominant NIS in the sessile community, we conducted an experiment where colonies of S. errata, D. perlucidum and the cryptogenic ascidian Botrylloides niger were submitted to the following three interaction scenarios: colonies growing without competition, under intraspecific competition and under interspecific competition. All competition treatments were crossed with the following two predation treatments: exposed or protected to predators. The experiment was repeated in two different seasons (Winter and Summer). When released from predation and competition, the three species grew at least 10 times faster in the Summer than in the Winter, and S. errata always grew slower than the ascidian species. Predation reduced D. perlucidum survival in the Winter but not during the Summer, when the fast colony growth seemed to buffer partial colony removal by predation. Colonial growth of B. niger was affected by competition only in treatments without predators, growing almost 50% more without competition than when competing, regardless of the competitors' identity. When exposed to predation, D. perlucidum was more limited by interspecific than intraspecific competition. S. errata growth was not affected by biotic interactions and was linked to intrinsic seasonal variation. Mineralized clonal organisms, such as bryozoans, were less predated than most of the ascidians species but they grew slower. Ascidians were more often predated but were also strong competitors that were able to overgrow several taxa. The contrasting growth strategies resulted in different successes of NIS and cryptogenic species at the studied locality. Ascidians were favored under low predation pressure while bryozoans were survivors when predation was intense. [ABSTRACT FROM AUTHOR]

Plant strategies against herbivores are classically divided into chemical, physical, biotic defences. However, little is known about the relative importance of each type of plant defence, especially in the same species. Using the myrmecophyte Triplaris americana (both with and without ants), and the congeneric non-myrmecophyte T. gardneriana, we tested whether ant defence is more effective than other defences of naturally ant-free myrmecophytes and the non-myrmecophyte congeneric species, all spatially co-occurring. In addition, we investigated how plant traits vary among plant groups, and how these traits modulate herbivory. We sampled data on leaf area loss and plant traits from these tree groups in the Brazilian Pantanal floodplain, and found that herbivory is sixfold lower in plants with ants than in ant-free plants, supporting a major role of biotic defences against herbivory. Whereas ant-free plants had more physical defences (sclerophylly and trichomes), they had little effect on herbivory-only sclerophylly modulated herbivory, but with opposite effects depending on ants' presence and species identity. Despite little variation in the chemicals among plant groups, tannin concentrations and δ 13 C signatures negatively affected herbivory in T. americana plants with ants and in T. gardneriana, respectively. We showed that ant defence in myrmecophytic systems is the most effective against herbivory, as the studied plants could not fully compensate the lack of this biotic defence. We highlight the importance of positive insect-plant interactions in limiting herbivory, and therefore potentially plant fitness., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

One of the unresolved issues in the ecology of parasites is the relationship between host specificity and performance. Previous studies tested this relationship in different systems and obtained all possible outcomes. This led to the proposal of two hypotheses to explain conflicting results: the trade-off and resource breadth hypotheses, which are treated as mutually exclusive in the literature and were corroborated by different studies. In the present study, we used an extensive database on avian malaria from Brazil and combined analyses based on specificity indices and network theory, in order to test which of those hypotheses might best explain our model system. Contrary to our expectations, there was no correlation between specificity and prevalence, which contradicts both hypotheses. In addition, we detected a strong modular structure in our host–parasite network and found that its modules were not composed of geographically close, but of phylogenetically close, host species. Based on our results, we reached the conclusion that trade-off and resource breadth hypotheses are not really mutually exclusive. As a conceptual solution we propose “The Integrative Hypothesis of Parasite Specialization”, a novel theoretical model that explains the contradictory results found in our study and reported to date in the literature. [ABSTRACT FROM AUTHOR]

Plants have traits against herbivory that may occur together and increase defense efficiency. We tested whether there are defense syndromes in a cerrado community and, if so, whether there is a phylogenetic signal in them. We measured nine defense traits from a woodland cerrado community in southeastern Brazil. We tested the correlation between all pairs of traits and grouped the species into defense syndromes according to their traits. Most pairwise correlations of traits were complementary. Plants with lower specific leaf area also presented tougher leaves, with low nitrogen, more trichomes, and tannins. We found five syndromes: two with low defenses and high nutritional quality, two with high defenses and low nutritional quality, and one with traits compensating each other. There were two predominant strategies against herbivory in cerrado: 'tolerance' and 'low nutritional quality' syndromes. Phylogeny did not determine the suite of traits species presented. We argue that herbivory exerts significant selection pressure on these plant defense traits. [ABSTRACT FROM AUTHOR]

This study has as reference the works by Fama and French (2002) accomplished with data of North American companies and by Brito and Silva (2003) accomplished with data of Brazilian companies. This work tested the forecasts of the tradeoff and pecking order theories on indebtedness and payout, using the methodology by Fama and McBeth (1973). The results demonstrated that Brazilian companies increased the remuneration goal, however they still distribute a small proportion of the profits, if compared to the American pattern, in spite of the Brazilian legislation to be quite favorable. The results indicate that the payout is negatively related with the investment opportunities and that the dividends don't suffer variation of short period to accommodate the investments, as it defends the theory of the pecking order. The profitability demonstrated to be relevant in the determination of the indebtedness politics, what indicates that the most profitable companies are less indebted confirming the pecking order. Besides, the variable "size" demonstrated to be significant in the indebted politics, corroborating pecking order and trade-off theories. [ABSTRACT FROM AUTHOR]

Organisms acquire energy from environment and must allocate it among different life traits (growth, maintenance and reproduction). Social insects must manage the energy allocation to various levels such as colony growth and caste functions. Here, we addressed the question of whether resource density affects the energy allocation to the number of individuals and caste functions as well as nest's growth rate in the Neotropical termite Nasutitermes aff. coxipoensis (Homgren) (Termitidae: Nasutitermitinae). In a manipulative field experiment, colonies of N. aff. coxipoensis, with known volume, were maintained in plots with three different resource's density (0.32, 0.64 and 1.92 baits/m 2 ) over 3 months. After this period, the number of individuals as well as the caste identity and nest volume were measured. Surprisingly, our results showed that colonies reared in the extremes of resource's density (0.32 and 1.92 baits/m 2 ) produced a higher number of individuals compared with colonies reared with intermediate resource density (0. 64 baits/m 2 ). The mean number of workers increased linearly with resource density; however, the average number of immature was higher in colonies reared with 0.32 baits/m 2 compared with colonies reared with 0.64 and 1.92 baits/m 2 . No significant differences of resource density were observed in the mean number of soldiers, worker/soldier ratio as well as in the nest's growth rate. In conclusion, the resource's density seems to play an important role in determining the investment of energy in the number of individuals and caste in N. aff. coxipoensis colonies.

Faster growth in tropical trees is usually associated with higher mortality rates, but the mechanisms underlying this relationship are poorly understood. In this study, we investigate how tree growth patterns are linked with environmental conditions and hydraulic traits, by monitoring the cambial growth of 9 tropical cloud forest tree species coupled with numerical simulations using an optimization model. We find that fast-growing trees have lower xylem safety margins than slow-growing trees and this pattern is not necessarily linked to differences in stomatal behaviour or environmental conditions when growth occurs. Instead, fast-growing trees have xylem vessels that are more vulnerable to cavitation and lower density wood. We propose the growth - xylem vulnerability trade-off represents a wood hydraulic economics spectrum similar to the classic leaf economic spectrum, and show through numerical simulations that this trade-off can emerge from the coordination between growth rates, wood density, and xylem vulnerability to cavitation. Our results suggest that vulnerability to hydraulic failure might be related with the growth-mortality trade-off in tropical trees, determining important life history differences. These findings are important in furthering our understanding of xylem hydraulic functioning and its implications on plant carbon economy., (© 2017 John Wiley & Sons Ltd.)