Worldwide, invasive non-native plant and wildlife species critically degrade natural processes within ecosystems and are a direct result of human influence. Often they do not have the natural checks and balances (diseases, pests, climate factors, predators, etc.) found in their native habitats.

Invasive non-native plant species in RBNERR are a significant management issue. Dominant invasive species include Australian pine, Brazilian pepper, melaleuca, latherleaf, climbing fern and a number of other non-native plants that are disrupting the native biodiversity of RBNERR natural communities. Natural communities that are at highest risk include those located on barrier islands and within transition zones such as freshwater marshes.

Invasive animals found in RBNERR include feral hogs, found on barrier islands and uplands within RBNERR. Feral hogs have recently been observed by staff depredating sea turtle nests on Keewaydin Island, located within RBNERR boundaries. Other non-native animals observed in RBNERR include spiny iguanas, Burmese pythons and marine invasives such as the Asian green mussel or African cichlids.