The primary impact of invasive species on local fauna is the disruption of native ecosystems. Invasive species can outcompete indigenous species for resources, often leading to declines or extinctions. They can alter food webs and ecosystem functions, destabilizing habitats and causing shifts in biodiversity. Furthermore, invasives may introduce new diseases or parasites that native species are ill-equipped to handle. These dynamics not only threaten local fauna but can also have cascading effects on overall ecosystem health, necessitating management efforts to control invasives and restore native balance.