A importância de adaptações comportamentais do javali (sus scrofa) no processo de invasão de savanas tropicais

Abstract

Biological invasions are among the five main drivers of biodiversity loss on a global scale due to their negative impacts, such as altering the trophic structure of communities and increasing competition for resources. In this context, the wild boar (Sus scrofa) and all of its forms (wild pigs or feral pigs) are among the world's 100 most invasive species and has one of the largest geographical distributions among terrestrial mammal species, primarily due to its introduction for sport hunting in different countries, along with habitat-related ecological factors and its high reproductive potential. A significant number of records of this species in South America come from three biomes considered biodiversity hotspots, including the Brazilian Cerrado. Despite this, few studies on the invasion ecology of this species in the biome have been conducted. This project aimed to identify the main factors associated with the abundance and presence of wild pigs in Brazilian savannas and to determine the population density of the species in the study area. Twelve camera traps were installed in an area of the Brazilian Cerrado, and medium and large mammals were monitored over 56 weeks. Generalized linear models (GLM) were used to analyze the factors associated with abundance. Factors related to presence were determined through Mackenzie’s occupancy analysis, and population density was estimated using Dail and Madsen’s method. The influence of variables was determined using Akaike’s Information Criterion (AIC). The results showed that factors associated with thermal relief mechanisms and the high density of the macaúba palm (Acrocomia aculeata) as a food resource had the greatest influence on the occurrence of wild pigs. Population density was estimated at approximately 109 individuals per area and showed significantly higher abundance during the rainy season. We concluded that wild pigs exhibit a high dependence on thermal relief mechanisms in environments with high temperatures, such as the Cerrado, and that natural resources play a fundamental role in their diet. We present one of the few studies of wild pigs’ invasion in Brazilian savannas. We hope our findings will guide prevention and management actions for the species in these environments across different countries.