Implications of Fine-Grained Habitat Fragmentation and Road Mortality for Jaguar Conservation in the Atlantic Forest, Brazil

Abstract

Jaguar (Panthera onca) populations in the Upper Paraná River, in the Brazilian Atlantic Forest region, live in a landscape that includes highly fragmented areas as well as relatively intact ones. We developed a model of jaguar habitat suitability in this region, and based on this habitat model, we developed a spatially structured metapopulation model of the jaguar populations in this area to analyze their viability, the potential impact of road mortality on the populations' persistence, and the interaction between road mortality and habitat fragmentation. In more highly fragmented populations, density of jaguars per unit area is lower and density of roads per jaguar is higher. The populations with the most fragmented habitat were predicted to have much lower persistence in the next 100 years when the model included no dispersal, indicating that the persistence of these populations are dependent to a large extent on dispersal from other populations. This, in turn, indicates that the interaction between road mortality and habitat fragmentation may lead to source-sink dynamics, whereby populations with highly fragmented habitat are maintained only by dispersal from populations with less fragmented habitat. This study demonstrates the utility of linking habitat and demographic models in assessing impacts on species living in fragmented landscapes.

Using road patrol data to identify factors associated with carnivore roadkill counts

“…Over 40% of Eurasian badgers in southwest England, for example, were thought to be killed each year in WVCs (Clarke, White & Harris, 1998). WVCs accounted for 35% of annual mortality of Florida panthers (Puma concolor coryi) in the USA (Taylor et al, 2002), 4-33% of annual mortality of jaguars (Panthera onca) in the Atlantic Forest, Brazil (Cullen et al, 2016), and 17% of annual mortality of Iberian lynx (Felis pardina) in southern Spain (Ferreras et al, 1992). Roadkill mitigation strategies could therefore contribute significantly conservation efforts for some species, so identifying factors that are associated with high roadkill rates is a useful first step.…”

Consequences of impediments to animal movements at different scales: A conceptual framework and review

“…However, accessing spatially separated resources can carry a higher mortality risk, such as through predation or vehicle collisions, than accessing resources within continuous habitat (Cullen et al, 2016;Rodríguez, Andrén, & Jansson, 2001) and incurs increased energetic costs (Hinsley, 2000), especially when individuals deliberately travel longer routes to avoid gaps .…”

Population Genetic Structure and Habitat Connectivity for Jaguar (Panthera onca) Conservation in Central Belize.

“…Wildlife Sanctuary, which were a continuum of jaguar habitat in the distant past but that still maintain a single genetic population. Movement corridors are essential to maintain the genetic connectivity for wide-ranging carnivores like jaguars(23,40) and are an example of an effective conservation strategy that could be implemented in other areas of the species range, such as those in the Atlantic Forest of South America, where there is a lack of genetic and landscape connectivity among isolated remnant jaguar populations(3,24,41,42). The effect of jaguar corridors on the species conservation is an effective conservation strategy that has also contributed significantly to the conservation and connectivity of a larger number of co-occurring species(40).Anthropogenic barriers and accelerated rates of habitat conversion into agricultural lands are likely to alter gene flow between core jaguar areas if these are not effectively connected(3,6,42,43).…”

“…In this study, we identified several areas in central Belize that are likely to be used by jaguars as they move through the landscape and that represent potential locations for priority management to ensure continued gene flow(Figures 1, 2). In particular, the negative impact of roads on jaguar populations should be considered to improve existing corridors or in the design of new ones; for example, roads can block the movement of wildlife, and also open up areas to hunters(4,41,43).Using circuit theory, we incorporated landscape features to predict suitable pathways for jaguar movement between the Maya Forest Corridor and the Cockscomb Basin Wildlife Reserve. We pinpointed two main areas of connectivity between Sittee River Forest Reserve and Manatee Forest Reserve along 'Hummingbird Highway', a clear anthropogenic boundary between the two sites (Figure 2).…”