How do invasive predators and competitors displace native species?

Invasive species displace native populations by disrupting established ecosystems through two primary mechanisms: predation and competition for limited resources.12

Invasive Predators

Invasive predators often possess a competitive advantage because the local ecosystem lacks natural controls to keep their populations in check. These predators can be so efficient at capturing prey that native populations decline rapidly, sometimes leading to localized extinction. For example, the introduction of brown tree snakes to Guam decimated native bird and reptile populations, while red foxes in Australia have caused significant declines in native marsupials and rodents.12

Competitive Displacement

Invasive species also displace natives by outcompeting them for essential resources such as food, sunlight, or living space. This process is governed by the principle of competitive exclusion, which states that two species competing for the same ecological niche cannot coexist indefinitely; one will eventually be driven out or become extinct. For instance, Asian carp aggressively compete with native fish for food, while invasive plants like kudzu deprive native flora of necessary sunlight.1234