A study that monitored 54 jaguars (Panthera onca) in forests, agricultural areas, and along roads and watercourses in different regions of South America indicated that the felines frequently leave the dense forest and return to its edges and farming areas. “Jaguars behaving like this are probably hunting, but they prefer larger forest fragments, which is where they spend more time,” says Bolivian biologist Vanesa Bejarano Alegre, who carried out the study as part of her PhD, concluded in 2023 at São Paulo State University (UNESP), Rio Claro campus.
The researcher is the lead author of an article published in December in the Journal Perspectives in Ecology and Conservation. “The jaguar plays an important role in ecosystem balance; its presence helps to regulate the reproduction of certain species,” explains Alegre. “Where there are jaguars there are clean waters, plants, insects, and a functional ecological chain.”
The animals were monitored by GPS collars, with data recorded every four hours, across twelve areas of study, and Alegre recorded the time period in which the animals moved within a 250-meter (m) radius of each site, how often they revisited sites, their speed of movement, and the time of the last visit. For their welfare, the collars do not weigh more than 3% of the animals’ weight (in the Pantanal, an adult jaguar may weigh up to 140 kilograms). “The problem is capturing the animals, because they have vast territories, the smallest of which can measure up to 40 square kilometers (km),” explains vet Ronaldo Morato, director of feline conservation NGO Panthera, and coauthor of the article.
Loop snares are used to fit the animals with the collars. “They trap the animal’s foot and activate an alarm,” explains Morato. “We immediately subdue them with anesthetic, install the collar, and take blood samples or collect other information, depending on the study.” The installed equipment then sends information via satellite at a frequency set by the researchers. From the data collected, speed of movement, acceleration, and direction can be calculated, enabling us to understand different behaviors among these felines. The collars are programmed to fall off after a certain period of time to obviate the need for recapture.
Morato coordinated the National Center for Carnivorous Mammal Research and Conservation (CENAP) for 18 years to 2023, and in 2018 published an article in the journal Ecology, presenting a public database with 134,690 localizations of 117 jaguars monitored by GPS across five South American countries. From these data, Alegre selected 54 animals whose movement allowed more regular monitoring.
Scrutinized wanderings
The time spent in each forest area demonstrates that, whether for feeding or shelter for themselves or their prey, the forests are paramount for jaguar conservation. “We have seen this animal increasingly cornered due to the loss of vegetation caused by urban expansion and farming,” points out biologist Rogério Cunha de Paula, who coordinates CENAP, an arm of the Chico Mendes Biodiversity Conservation Institute (ICMBio). “Hence the importance of studies like this, which combine satellite image data with data from GPS, and demonstrate the jaguar’s significant dependence on habitats of better quality.”
Brazil is home to the world’s biggest population of jaguars, once found in all other biomes; it is not currently seen in the Pampa region. An article published in 2018 in the journal PLOS ONE, a reference for studies on the geographical distribution of these animals in Brazil, indicates concentrated presence in the Pantanal and Amazonia. Only isolated traces can be found in other biomes.
One issue with regions only providing restricted swathes of forest is that the fragments may not be sufficient in size to house males that migrate away from their birth groups, who in some cases end up alone in distant, significantly reduced areas. “They go in search of a new territory and live there until they die, because they are unable to reproduce,” warns De Paula. “This is a big risk because we have few suitable areas, and for some decades now populations have been declining and heading toward local extinction.”
To prevent this scenario being multiplied, ecological corridors are needed to connect forest fragments, including those on rural properties, along with the formulation of conflict mitigation strategies. According to Alegre, the mapping of priority conservation areas requires the inclusion of buffer zones installed with sustainable resources, such as agroforests, and careful management of roads, including unpaved, within the boundaries of the properties. “What I perceive from this study and others that we have conducted is that one of the greatest impacts for jaguars is the road system, because jaguars use these routes, whether for more efficient movement, or because they can find prey killed by vehicle collisions.”
Ecological corridors would also prevent collisions with the jaguars themselves. Though it is difficult to arrive at an accurate number of these type of mortalities, CENAP has been receiving more notifications in recent years. “We have increasing registrations of jaguars being run over, particularly in the deforestation arc,” emphasizes Rogério de Paula, referring to the region on the southern and southeastern edge of the Brazilian Amazon forest. “These are areas that the animals used, and suddenly they became access ways, with paved roads or secondary highways being laid for the distribution of agricultural output.”
The study led by Alegre reveals that jaguars move more quickly close to roads and avoid staying for too long in these areas. “This suggests risk-avoidance behavior,” she explains. On the other hand, their movement is slower close to watercourses, where the animals pay frequent return visits.
Biologist Ricardo Boulhosa believes that this finding validates a common maxim for habitat conservation and environmental planning. “We always say that you need water and trees to have jaguars, and this study proves that. It is a research project that provides refined data on the ecology of these animals and guides the management of farming areas.” Boulhosa is a researcher at the Pro-carnivore Institute, a nonprofit organization promoting the conservation of neotropical carnivorous mammals and their habitats for almost 30 years. Like Rogério de Paula, he did not participate in the study.
The story above was published with the title “Where jaguars drink water” in issue in issue 348 of february/2025.
Projects
1. Movement ecology of a neotropical top predator in different habitats and how it interacts with prey (nº 18/13037-3); Grant Mechanism Doctoral Fellowship; Supervisor Milton Cezar Ribeiro (UNESP); Beneficiary Vanesa Fabiola Bejarano Alegre; Investment R$356,059.18.
2. Biodiversity and associated services: Cantareira Mantiqueira Corridor PELD (nº 21/08534-0); Grant Mechanism Regular Research Grant; Principal Investigator Milton Cezar Ribeiro (UNESP); Investment R$309,404.64.
3.Biodiversity in the Anthropocene:Effect of agroecosystems on biodiversity conservation and maintenance of ecosystem functions (nº 20/01779-5); Grant Mechanism Regular Research Grant; Principal Investigator Milton Cezar Ribeiro (UNESP); Investment R$188,626.99.
4. Contributions of payment for environmental services on multiple dimensions in the Atlantic Forest (nº 21/10195-0); Grant Mechanism Thematic Project; Principal Investigator Milton Cezar Ribeiro (UNESP); Investment R$3,054,695.07.
Scientific articles
ALEGRE, V. B. et al. Jaguar at the Edge: Movement patterns in human-altered landscapes. Perspectives in Ecology and Conservation. Vol. 22, no. 4, pp. 358–66. Oct.–Dec. 2024.
ALEGRE, V. B. et al. The effect of anthropogenic features on the habitat selection of a large carnivore is conditional on sex and circadian period, suggesting a landscape of coexistence. Journal for Nature Conservation. Vol. 73, 126412. June 2023.
JĘDRZEJEWSKI, W. et al. Estimating large carnivore populations at global scale based on spatial predictions of density and distribution – Application to the jaguar (Panthera onca). PLOS ONE. Vol. 13, no. 3, e0194719. Mar. 26, 2018.
MORATO, R. G. et al. Jaguar movement database: A GPS-based movement dataset of an apex predator in the Neotropics. Ecology. Vol. 99, no. 7, p. 1691. July 2018.
