dc.description.abstract | Human changes in the terrestrial biosphere threaten natural habitats, putting at risk wild
animal and plant species, their ecological interactions and the ecosystem services provided by
the environment as a whole. Given the intensity of human changes on the planet, the term
Anthropocene was proposed to characterize the current geological epoch dominated by
humans. The Iron Quadrangle (QF), southeast of the state of Minas Gerais, Brazil, is an
example of a region affected by human activities for centuries and which is responsible for
providing essential ecosystem services for the region with the highest human density in the
state of Minas Gerais, the capital Belo Horizonte and surrounding cities. In this region, the
natural habitats are intersected by an anthropic matrix, restricting wild species to smaller and
smaller native remnants. The tapiti (Sylvilagus brasiliensis), a species present in the QF, is an
exclusive herbivore and the only representative of lagomorphs in Brazil. The species is
responsible for a range of ecosystem services, such as cycling of nutrients present in its feces,
acting on the population dynamics of plants through grazing and seed dispersal, influencing
species composition through the predator-prey relationship and exerting influence on
populations of invertebrates that use their feces to feed or reproduce. Combining the camera
traps (AFs) method with occupation models, we evaluated how and which natural (i.e., water
bodies and forest, cerrado and rupestrian fields) and anthropogenic (i.e., eucalyptus, mining,
pasture, paved and unpaved roads and railroad and urbanization) would influence the
probability of occupation (Ψ) and detection (p) of the tapiti in the QF. None of the variables
influenced the probability of occupation of the tapiti (w+ < 0.50), which was low (Ψ = 0.21;
95%CI = 0.10 – 0.32), indicating that the species is restricted to a few natural habitats and,
therefore, generating great uncertainty about the long-term presence of the species in the QF.
On the other hand, the detection probability correlated positively with the distance for
Eucalyptus plantations (w+ = 0.65), suggesting that the tapiti uses with lower intensity native
areas surrounded by Eucalyptus, which may be related to the absence of understory in these
areas and, therefore, a lower availability of resources and refuges for the species. The
detection probability also correlated negatively with the distance to pasture areas (w+ = 0.57),
suggesting that the tapiti uses native areas surrounded by pastures more intensively, which
may be related to a greater availability of resources for the tapiti, as is the case of invasive
exotic grasses that may even be being dispersed by the tapiti to other locations and, therefore,
increasing their distribution in the region. The present study is the first to quantitatively
14
evaluate the influence of landscape variables on the probability of occupation and detection of
the tapiti. We believe that our study can contribute to the direction of mitigation measures and
strategies for the conservation of tapiti in a scenario of intense conversion of native habitats,
demonstrating, for example, the need to manage Eucalyptus plantations and pastures for a
respective increase in distribution of the species and so that the ecosystem services performed
by it are restricted to the native environments of the QF. | |