Effects of anthropogenic disturbance and land cover protection on the behavioural patterns and abundance of Brazilian mammals

Abstract

Governmental and private protected areas are a key focus of conservation concern, as they tend to be associated with greater biodiversity and abundance of threatened mammals than non-protected areas. Protected areas are also effective at limiting anthropogenic pressures that threaten endemic species. Behavioural shifts are often the most immediate response of animals to disturbance, indicating the importance of considering the direct links between the disturbance present in an ecosystem and the behavioural patterns of endemic species. Here, we assessed the effect of land cover protection along with anthropogenic disturbance factors (human and dog abundance, distance to the nearest house, percentage of native vegetation [relative to agricultural landscapes]) on the activity patterns and abundance of 6 mammal species in the Brazilian Atlantic Forest and Cerrado. Data were collected using camera traps employed during 2 dry seasons at 208 stations (6240 camera-days). Activity pattern analyses used the novel application of circular activity patterns and a direct circular outcome to assess the direct impact of protection status and anthropogenic disturbance on behavioural shifts in the mammal species. Relative abundance was calculated using the mean population size of individuals as well as the per-individual detection probability. Protection status significantly elicited behavioural shifts in 5 of the 6 mammals, with 4 of these mammals shifting more towards nocturnality in non-protected areas. Dog abundance was the most important covariate in activity pattern shifts in the giant anteater, with nocturnality increasing with dog abundance, whereas native vegetation was the most important covariate in activity pattern shifts in the agouti and puma, with nocturnality increasing with decreasing native vegetation. Relative abundance was significantly lower in non-protected areas in 2 mammals, one of which was the Vulnerable giant anteater. The findings here are the first time in which anthropogenic disturbance factors have been found to directly elicit shifts in the circular activity patterns of mammals, as well as highlight the importance of protected areas in mammal conservation. The methods used here can be applied to ecosystems globally to pinpoint the direct impact of disturbance factors on endemic species whilst also providing explicit information on how conservation initiatives can be strategically and effectively targeted.