Juarez Carlos Brito Pezzuti

Amazonian people are highly dependent on fishing, which provides their main source of protein. Fishing in the middle Caeté, Eastern Amazon, Pará, Brazil, was described in terms of the sociodemographic profile of fishers, gear, and strategies used in catches. Semi-structured interviews were conducted with fishers in the region. Fishing occurs throughout the year, and to a lesser extent during the closed season. It is characterized as subsistence fishing, although a small percentage (20%) sell part of their catch to supplement their income. Fishing gear is diverse and varies according to the seasons, with gillnets and set longlines being the most common. Transportation is carried out aboard small canoes powered by oars or outboard motors. The most important commercialized species are the giant Malaysian prawn, dourada, and piramutaba, while traíra, mandií, tuvi, anujá, aracu, piranha, among others, are intended for family consumption. A change in fishers’ habits is expected in terms of increasing the mesh size of gillnets to be more selective and to comply with fishing regulations.

The Xingu River is facing impacts from the recently built Belo Monte Hydropower Plant (HPP), which is jeopardizing the pacus (herbivorous fish of the family Serrasalmidae and primary food source for the Yudjá people) derived from the Big Bend of Xingu (BBX). Part of the water volume in the BBX was redirected to an artificial canal as part of the Belo Monte HPP project. Thus, this study aims to analyze the trophic ecology of pacus through diet analysis and the Local Ecological Knowledge (LEK) of the Yudjá people using a qualitative-quantitative approach on the diet of those fish and check potential changes in fish welfare (mass/total legth3) in the BBX after the construction of the Belo Monte HPP. Overall, 133 specimens of eight herbivorous serrasalmid species were sampled after the damming, and previous data on 107 fish specimens of five species were gathered from landings. Terrestrial plants, fruits, and aquatic plants have the highest dietary importance for these fish, indicating the great importance of floodplains and rapids for herbivorous serrasalmids. Well-being, body size, and total mass show that these fish are already being negatively affected by the damming. The Yudjá are thus already feeling these impacts. The current water flow in the BBX is meagre for fish maintenance, and consequently, for the Yudjá people in BBX. Therefore, the amount of water flow to the BBX needs revision to avoid irreversible impacts.

The identification of animals at an individual-level is the key for studies of wildlife abundance, density, and population dynamics parameters, such as reproduction and survival. The Wildbook is an online and free database employed to identify a wide range of species at the individual-level by comparing their individual marks in photographs, provided either by citizen science endeavors or passive monitoring. Here, we present the first record of the use of the Whiskerbook platform to identify spotted species in South America. The data was obtained by the camera trap monitoring performed at the Ecological Station Terra do Meio in Brazil throughout five years, with an average of 60 cameras/year and a total of 20.668 days of records. We identified at least 78 ocelots along the five years of monitoring, from a total of 810 camera trap records. Recaptures were recorded from four years and occurred always within one year from the first capture. Recaptures were also recorded within the same year and place for 17 ocelot individuals and co-occurrences suggested that a mean of 3.7 individuals were recorded sharing 14 cameras over the years. Despite Whiskerbook’s limitations, it has demonstrated to be a promising tool for conservation issues, and its potential should be further explored by wildlife researchers.

Coloration is crucial for mammalian adaptation, influencing predator defense and social behavior. In recent decades, chromatic anomalies have been documented in Neotropical mammals, including albinism, leucism, and piebaldism, affecting several species. Piebaldism is a rare autosomal disorder characterized by asymmetric depigmented patches on the body. This study presents the first record of piebaldism in the collared peccary (Dicotyles tajacu Linnaeus, 1758) throughout its distribution. The record was obtained using camera traps at the Estação Ecológica (ESEC) da Terra do Meio in 2023. Observations showed that the affected peccary coexisted normally with other peccaries and engaged in typical feeding and social behaviors, suggesting that piebaldism does not affect individual social interactions. This finding is consistent with the literature indicating that chemical signals are more important than visual signals in Tayassuidae. This finding highlights the need to understand the frequency and distribution of chromatic anomalies to assess their implications for conservation plans over time.

Summary: The Neotropics have vast river catchments with untapped hydroelectric potential, but there are multiple expected negative impacts of dams, including those on local food security and livelihoods. Yet, monitoring of dam effects on subsistence is rare, particularly during initial implementation. Our study assessed changes in human fish consumption near the Belo Monte Dam in the Brazilian Amazon during the period 2012–2021, which covers construction, operation and a severe El Niño-induced drought. Over time, fish became less common and were consumed in smaller amounts, even though fewer people shared meals. The largest changes occurred between 2013 and 2016 (post-construction but prior to full operation), resulting in a downward trend in fish consumption, particularly during the drought season. Adding more fish species to the diet did not increase consumption per person. These changes in fish consumption suggest that they stem from environmental impacts of the project (e.g., reduced river level), despite secondary effects from climatic events. These findings underscore the urgent need for comprehensive assessments of the social and ecological impacts of large infrastructure projects in the Amazon, along with sustainable and equitable management strategies to ensure food security and meet the needs of local communities.

Polycystic Echinococcosis (PE), a neglected life-threatening zoonotic disease caused by the cestodeEchinococcus vogeli,is endemic in the Amazon. Despite being treatable, PE reaches a case fatality rate of around 29% due to late or missed diagnosis. PE is sustained in Pan-Amazonia by a complex sylvatic cycle. The hunting of its infected intermediate hosts (especially the lowland pacaCuniculus paca) enables the disease to further transmit to humans, when their viscera are improperly handled. In this study, we compiled a unique dataset of host occurrences (~86000 records) and disease infections (~400 cases) covering the entire Pan-Amazonia and employed different modeling and statistical tools to unveil the spatial distribution of PE’s key animal hosts. Subsequently, we derived a set of ecological, environmental, climatic, and hunting covariates that potentially act as transmission risk factors and used them as predictors of two independent Maximum Entropy models, one for animal infections and one for human infections. Our findings indicate that temperature stability promotes the sylvatic circulation of the disease. Additionally, we show how El Niño-Southern Oscillation (ENSO) extreme events disrupt hunting patterns throughout Pan-Amazonia, ultimately affecting the probability of spillover. In a scenario where climate extremes are projected to intensify, climate change at regional level appears to be indirectly driving the spillover ofE. vogeli. These results hold substantial implications for a wide range of zoonoses acquired at the wildlife-human interface for which transmission is related to the manipulation and consumption of wild meat, underscoring the pressing need for enhanced awareness and intervention strategies.

Context: Waterfalls and rapids of Amazon basin have been suggested as causing the speciation and genetic structure of many freshwater species, including turtles. The species behavior affects the way waterfalls and rapids limit gene flow. The Yellow-spotted River Turtle ( Podocnemis unifilis ), a widely distributed and endangered Amazonian turtle, does not show the habit to migrate long distances for breeding or eating, but has a complex geographic pattern of genetic variation. Objectives: Here, we investigate isolation by distance and by resistance of P. unifilis . We analyzed if the species ecological niche and waterfalls explain the genetic distance in Brazilian Amazonia. Methods: We evaluated the P. unifilis spatial distribution of genetic variability and diversity using the control region of mitochondrial DNA. We tested the hypotheses of isolation either by distance and resistance through an integrative approach using genetic, geographic, and ecological data. We created a resistance matrix using species niche modeling. We compared the explanation power of geographical distance (both linear and in-water distance) and resistance distance on genetic distance (ΦST fixation index) using multiple regressions and Mantel tests. Results: We found a high genetic diversity and pattern of genetic structure proved to be geographically complex. The population structure followed some watersheds but also showed structuring within different rivers. We found that landscape resistance better explains genetic distance than linear and in-water distance. Conclusions: The resistance of the landscape influences the displacement of individuals by aquatic, vegetational, biological, and geomorphological variables, and efforts to species conservation need to be applied throughout its distribution considering landscape genetics.

Freshwater turtles are a valuable food resource for riverine human communities and have been historically overharvested throughout all major tropical large river basins, with consequent gradual population decreases. Even species considered to be abundant are declining, and in many cases were brought to a condition of near extinction. The collection of adult females during breeding season on nesting beaches is considered a major factor in population decline and subsequent loss of food sources for humans. There is growing consensus that adult females constitute the category which turtle populations can least afford to lose. In the Negro River Basin, the podocnemidid big-headed Amazon River turtle,Peltocephalus dumerilianus, is heavily exploited for consumption and poached for illegal trade among riverine communities and cities. Between 1997 and 2002 and in 2019, we measured live turtles and carapaces of big-headed turtles in the city of Barcelos and its surroundings, and among the riverine families living in the Jaú National Park. We compared body sizes and sex ratios between areas, periods, and between consumed and traded individuals. We found no differences between areas, even those close to Barcelos and the ones belonging to remote areas where pressure levels are lower. The individuals consumed in Jaú National Park are larger than those poached for illegal trade in both areas. There was an increase in average size between 1997 and 2002. Sex ratio was slightly skewed toward males, which were larger, and did not differ between areas and periods. Results indicate stability on size of harvested populations, which may be supporting current extraction levels. Data suggest this could be related to the absence of adult female capture during nesting for this species. We recommend protection strategies for other Amazon Podocnemidid species that focus on the protection of nesting beaches and surrounding areas where adults occupy, specifically in areas under communal protection.