The role of invasive species in the network of the Mediterranean ecosystem dominated by sclerophyllous vegetation of central Chile

The ecosystem dominated by sclerophyllous vegetation in central Chile has been defined as a biodiversity hotspot due to a combination of high levels of endemism and threats, such as biological invasions. Understanding how embedded these invasive species are within the community provides relevant information for decision-makers to conserve this ecosystem efficiently. For this purpose, a network of the sclerophyllous vegetation was constructed based on a bibliographic review of the distribution and diet of species, as well as an evaluation of its topological properties. Additionally, to identify the key invasive species within the network, centrality metrics and in silico extinction analysis were employed. The network comprises 252 species and 798 trophic interactions, with 63% basal, 33% intermediate, and 4% higher trophic levels. The European rabbit was consistently the invasive species with the highest centrality indices, followed by dogs, rats, mice and Californian quail. The in silico rabbit eradication analysis primarily resulted in the relief of herbivore pressure on several native and endemic plants ( e.g., Neltuma chilensis, Convolvulus chilensis ), which could regenerate in their absence and serve as resources for native herbivores, thereby reducing competition pressure. However, it reduced the dietary range of some native and threatened predators ( e.g., Galictis cuja, Leopardus guigna ). Managing invasive species is a priority for preserving the ecosystem dominated by sclerophyllous vegetation in central Chile. Therefore, it is necessary to conduct experimental exclusion studies and monitoring programs to assess the impact of invaders on the regeneration ecosystem and the most vulnerable species.