The increasing frequency and severity of human-caused fires likely have
deleterious effects on species distribution and persistence. In 2020,
megafires in the Brazilian Pantanal burned 43% of the biome’s unburned
area and resulted in mass mortality of wildlife. We investigated changes
in habitat use or occupancy for an assemblage of eight mammal species in
Serra do Amolar, Brazil, following the 2020 fires using a pre- and
post-fire camera trap dataset. Additionally, we estimated density for two
naturally marked species, jaguars Panthera onca and ocelots Leopardus
pardalis. Of the eight species, six (ocelots, collared peccaries Dicotyles
tajacu, giant armadillos Priodontes maximus, Azara’s agouti Dasyprocta
azarae, red brocket deer Mazama americana, and tapirs Tapirus terrestris)
had declining occupancy following fires, and one had stable habitat use
(pumas Puma concolor). Giant armadillo experienced the most precipitous
decline in occupancy from 0.431 ± 0.171 to 0.077 ± 0.044 after the fires.
Jaguars were the only species with increasing habitat use, from 0.393 ±
0.127 to 0.753 ± 0.085. Jaguar density remained stable across years (2.8 ±
1.3, 3.7 ± 1.3, 2.6 ± 0.85 / 100km2), while ocelot density increased from
13.9 ± 3.2 to 16.1 ± 5.2 / 100km2. However, the low number of both jaguars
and ocelots recaptured after the fire period suggests that immigration may
have sustained the population. Our results indicate that the megafires
will have significant consequences for species occupancy and fitness in
fire affected areas. The scale of megafires may inhibit successful
recolonization, thus wider studies are needed to investigate population
trends.