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result(s) for
"Morato, Ronaldo G."
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Impending anthropogenic threats and protected area prioritization for jaguars in the Brazilian Amazon
by
Peres, Carlos A.
,
Bogoni, Juliano A.
,
Oliveira-da-Costa, Marcelo
in
631/158/2450
,
631/158/851
,
Animals
2023
Jaguars (
Panthera onca
) exert critical top-down control over large vertebrates across the Neotropics. Yet, this iconic species have been declining due to multiple threats, such as habitat loss and hunting, which are rapidly increasing across the New World tropics. Based on geospatial layers, we extracted socio-environmental variables for 447 protected areas across the Brazilian Amazon to identify those that merit short-term high-priority efforts to maximize jaguar persistence. Data were analyzed using descriptive statistics and comparisons of measures of central tendency. Our results reveal that areas containing the largest jaguar densities and the largest estimated population sizes are precisely among those confronting most anthropogenic threats. Jaguars are threatened in the world’s largest tropical forest biome by deforestation associated with anthropogenic fires, and the subsequent establishment of pastures. By contrasting the highest threats with the highest jaguar population sizes in a bivariate plot, we provide a shortlist of the top-10 protected areas that should be prioritized for immediate jaguar conservation efforts and 74 for short-term action. Many of these are located at the deforestation frontier or in important boundaries with neighboring countries (e.g., Peruvian, Colombian and Venezuelan Amazon). The predicament of a safe future for jaguars can only be ensured if protected areas persist and resist downgrading and downsizing due to both external anthropogenic threats and geopolitical pressures (e.g., infrastructure development and frail law enforcement).
The most-at-risk habitats for jaguars in the Brazilian Amazon are identified and anthropogenic factors including deforestation and agriculture are highlighted as root causes of this habitat destruction.
Journal Article
Land Use Effects on the Space Use and Dispersal of an Apex Predator in an Ecotone Between Tropical Biodiversity Hotspots
by
Barban, Ananda de Barros
,
Vilalba, Ermeson A.
,
Alberico, Vanessa V.
in
Animals
,
Atlantic Forest
,
Behavior
2025
Assessing the ranging and dispersal behavior of apex predators and its consequences for landscape connectivity is of paramount importance for understanding population and ecosystem effects of anthropogenic land use change. Here, we synthesize ranging and dispersal ecological information on pumas (Puma concolor) and present estimates of how different land uses affect the space use and dispersal of pumas on fragmented landscapes in an ecotone between biodiversity hotspots in southeastern Brazil. Additionally, we evaluate the effect of animal translocations on dispersal and movement patterns. Using location data for 14 GPS-collared pumas and land use data, we assessed when, how long, and how far individuals dispersed; how forest loss and infrastructure influenced puma home range size; and how movement patterns changed according to land use and proximity to infrastructure, during ranging and dispersal, for residents, natural dispersers, and translocated individuals. We present the first detailed record on the dispersal of pumas in Brazil and in the tropics, including long-distance dispersals, and show that pumas moved faster and more linearly during dispersal than during ranging. Their movement was slower and their home ranges were smaller in more forested areas, underscoring the importance of forest as habitat. In contrast, movement rates were higher in open pastures, mainly during dispersal. Our study underscores the scarcity of research on puma space use and dispersal in South America and reveals partial divergences in dispersal behaviors compared to North America and temperate regions, especially concerning dispersal ages. Furthermore, we give the first steps in presenting how land cover and human infrastructure affect the movement of this apex predator in a tropical ecosystem, an important subsidy for land use management. We call for more comprehensive studies on the movement ecology of carnivores combined with long-term population monitoring, to allow linking individual behavior with metapopulation dynamics and landscape connectivity and drawing more effective measures to sustain their populations.
Journal Article
Deforestation, fires, and lack of governance are displacing thousands of jaguars in Brazilian Amazon
by
Menezes, Jorge F. S.
,
Oliveira‐Santos, Luiz G. R.
,
Tortato, Fernando R.
in
Agriculture
,
Biodiversity
,
Cattle
2021
The rate of deforestation and the number of large wildfires are increasing in the Amazon. Illegal loggers, miners, ranchers, and farmers all have contributed to this increase. Their activities have dramatic consequences for biodiversity, ecological services, and people. In this study, we estimated the number of jaguars affected by deforestation. We focused on the Brazilian Amazon from August 2016 to December 2019. Further, we analyzed the effects of socio‐geographic determinants of deforestation and state policies. To do so, we used deforestation data from DETER‐B satellite system. The number of jaguars within each deforested area was pulled from a previous study, which provided jaguar abundances for jaguar entire range. We assumed all jaguars within a deforested area were affected (displaced or killed). To determine the underlying causes of jaguar loss, we regressed the number of jaguars lost per state and year against the proportion of total forest area within reserves, distance to forest border, and monetary efficiency in cattle production. We estimate a total of 1,422 jaguars have been displaced/killed in recent years (2016: 488, 2017: 360, 2018: 268, 2019: 354). Only the proportion of protected area had an effect in reducing jaguar deforestation. We discuss how our work could result in near real‐time monitoring of jaguar displacement and how policies such as wood certification, more efficient cattle production, and centralizing governance may be solutions.
Journal Article
Extensive aquatic subsidies lead to territorial breakdown and high density of an apex predator
by
dos Santos-Filho, Manoel
,
Peres, Carlos A.
,
Ruprecht, Joel S.
in
allochthonous resources
,
Animals
,
Aquatic ecosystems
2022
Energetic subsidies between terrestrial and aquatic ecosystems can strongly influence food webs and population dynamics. Our objective was to study how aquatic subsidies affected jaguar (Panthera onca) diet, sociality, and population density in a seasonally flooded protected area in the Brazilian Pantanal. The diet (n = 138 scats) was dominated by fish (46%) and aquatic reptiles (55%), representing the first jaguar population known to feed extensively on fish and to minimally consume mammals (11%). These aquatic subsidies supported the highest jaguar population density estimate to date (12.4 jaguars/100 km²) derived from camera traps (8,065 trap nights) and GPS collars (n = 13). Contrary to their mostly solitary behavior elsewhere, we documented social interactions previously unobserved between same-sex adults including cooperative fishing, co-traveling, and play. Our study demonstrates that aquatic subsidies, frequently described in omnivores, can also transform the ecology and behavior of obligate carnivores.
Journal Article
Disturbance or propagule pressure? Unravelling the drivers and mapping the intensity of invasion of free-ranging dogs across the Atlantic forest hotspot
by
Metzger, Jean Paul
,
Pardini, Renata
,
Morato, Ronaldo G.
in
abundance models
,
Afforestation
,
Biodiversity
2019
Aim Identifying the drivers of biological invasions is crucial to predict the risk of invasion across broad spatial scales and to devise strategies to prevent invasion impacts. Here, we explore the relative importance and synergies between two key drivers—propagule pressure and landscape disturbance—in determining the invasion of native forest remnants by dogs, one of the most abundant, widely distributed, and harmful invasive species worldwide. Location Brazilian Atlantic Forest. Methods Combining a camera trap dataset (96 sites in forest remnants) and censuses of populations of dogs raised by humans across 12 landscapes (2,830 ha each), we used N‐mixture models that account for imperfect detection to confront alternative hypotheses of invasion drivers. We then used this empirical evidence to predict the intensity of dog invasion across the Atlantic Forest hotspot. Results Propagule pressure (density of raised dogs, positive effect) and landscape disturbance (forest cover, negative effect) were equally important drivers of dog invasion, presenting additive rather than synergistic effects. Dogs invade forest remnants far from their homes, making the density of raised dogs the key component of propagule pressure (relative to dog spatial distribution). Forest cover was more important than either the length or density of forest edges, suggesting that both reduced area of forested barriers to long‐distance movements and increased proximity of forests to edges facilitate dog access to forests. Across the Atlantic Forest, the combination of high human population density and extensive deforestation makes dog invasion an additional and widespread threat. Main conclusion Combined with available maps of priority areas for biodiversity conservation, our spatial prediction of dog invasion can help target areas for integrated management actions. These actions should go beyond measures to control dog populations and encompass the maintenance and restoration of native forests and strategic planning of afforestation through planted forests.
Journal Article
The bush dog Speothos venaticus: area requirement and habitat use in cultivated lands
by
Jorge, Maria Luisa S. P.
,
Morato, Ronaldo G.
,
Jorge, Rodrigo S. P.
in
Animals
,
Biotelemetry
,
Brazil
2015
We radio-tracked a pack of bush dogs Speothos venaticus (7–10 individuals) near Água Boa in Mato Grosso, Brazil, for 18 months to investigate their use of habitat in cultivated land. The pack's home range was 709 km2 (fixed-kernel 95%), which exceeds estimates of home range for the largest Neotropical carnivore, the jaguar Panthera onca. Of the 245 locations where the dogs were recorded 95% were within native vegetation (savannah and forest), even though these habitats comprised only 34% of the pack's home range. This indicates a preference for native vegetation, and this was reinforced by composition analysis of habitat use, which showed that the pack used savannah and forest more than expected and cultivated areas less than expected. Analysis of activity showed that the bush dogs were moving quickly in more than half of the locations in cultivated areas, foraging in most savannah locations and resting in most forest locations. Our results indicate that bush dogs can live in areas with a high proportion of cultivated land (66%), possibly because of the structural connectivity of the landscape (80% of the native habitat is within a single patch). However, their home range appears to be inflated compared to that of other carnivores, which may have a negative effect on the species in the long term.
Journal Article
A biodiversity hotspot losing its top predator: The challenge of jaguar conservation in the Atlantic Forest of South America
by
Paviolo, Agustin
,
Lima, Fernando
,
Xavier da Silva, Marina
in
631/158/2450
,
631/158/670
,
631/158/672
2016
The jaguar is the top predator of the Atlantic Forest (AF), which is a highly threatened biodiversity hotspot that occurs in Brazil, Paraguay and Argentina. By combining data sets from 14 research groups across the region, we determine the population status of the jaguar and propose a spatial prioritization for conservation actions. About 85% of the jaguar’s habitat in the AF has been lost and only 7% remains in good condition. Jaguars persist in around 2.8% of the region, and live in very low densities in most of the areas. The population of jaguars in the AF is probably lower than 300 individuals scattered in small sub-populations. We identified seven Jaguar Conservation Units (JCUs) and seven potential JCUs, and only three of these areas may have ≥50 individuals. A connectivity analysis shows that most of the JCUs are isolated. Habitat loss and fragmentation were the major causes for jaguar decline, but human induced mortality is the main threat for the remaining population. We classified areas according to their contribution to jaguar conservation and we recommend management actions for each of them. The methodology in this study could be used for conservation planning of other carnivore species.
Journal Article