An international study identified an area of around 6.5 million square kilometers that connects jaguar populations in 11 countries in South America. The region serves as a “backbone” for the conservation of the largest feline in the Americas. The research was published in the scientific journal Global Change Biology.
The work, led by Brazilian researcher Guilherme Costa Alvarenga, from the Mamirauá Institute and the University of Oxford, is the most comprehensive compilation ever made on the movement of the species.
The research was developed with data from 86 females and 86 males monitored with GPS collars, totaling 231,017 location records. The base brings together animals from different ecosystems and environmental conditions found throughout the species' range.
In South America, the survey found a large connected network involving Llanos, Amazonia, Gran Chaco, Pantanal, Cerrado, Caatinga, and the Atlantic Forest in the so-called Green Corridor, located between Argentina and Brazil. This is the largest and most significant connection network identified by the study.
In total, the researchers mapped 307 core areas, totaling around 7.75 million km², equivalent to 55% of the species' current distribution area. About half of this area is in protected areas and Indigenous Lands. The study also identified 176 dispersal corridors between these areas.
The connection, however, is not continuous. Roads, cities and agricultural areas interrupt or hinder the passage of animals and leave some populations increasingly isolated. In Mexico and Central America, several outages were found. In the Brazilian coastal Atlantic Forest, the areas occupied by the species appear largely isolated, both from the greater South American network and from each other.
According to the study, greater concentration of people, presence of herds and transformation of natural environments were the factors with the strongest negative effect on the movement of jaguars. More ecologically productive areas close to rivers, lakes and other bodies of water proved to be more favorable.
Isolation reduces the so-called gene flow, the exchange of genetic characteristics between animals from different populations. Without it, crossings between related individuals increase, which can reduce adaptation capacity and favor genetic diseases.
"When the natural environment is reduced and fragmented, fewer individuals are able to survive in that space. Furthermore, without the possibility of moving, animals begin to reproduce only within the same group, increasing crossings between related individuals. Over time, this can reduce the population's ability to adapt and favor diseases of genetic origin. This process has already been identified in jaguar populations in the Atlantic Forest and Central America, precisely where our models indicate low connectivity", explains Alvarenga.
The maps indicate where conservation actions can have the greatest effect, whether to protect populations, prevent existing connections from being broken or recover degraded paths. Among the measures highlighted are the restoration of areas important for displacement, the fight against hunting and the reduction of conflicts between people and big cats. In specific cases, the study also mentions the translocation or reintroduction of animals.
In a second analysis, the researchers specifically evaluated possible connections between protected areas and Indigenous Lands. The model identified 507 potential corridors among 905 areas distributed throughout the jaguar's current occurrence.
The study also highlighted potential connections that will need to be verified by further field research. One of them could connect the Darién region, on the border between Panama and Colombia, to the Llanos and the Amazon, passing through Colombia and Venezuela.
Another possible connection would connect the Verde–Iguaçu Corridor, on the border between Argentina and Brazil, to Serra do Mar, between Paraná and São Paulo. Both possibilities appeared in only one of the models and, therefore, should be interpreted with greater caution.
