"Eucalyptus" plantations in California have been criticised, because they compete with native plants and typically do not support native animals. "Eucalyptus" has historically been planted to replace California's coast live oak population, and the new Eucalyptus is not as hospitable to native flora and fauna as the oaks. In appropriately foggy conditions on the California Coast, "Eucalyptus" can spread at a rapid rate. The absence of natural inhibitors such as the koala or pathogens native to Australia have aided in the spread of California "Eucalyptus" trees. This is not as big of an issue further inland, but on the coast invasive eucalypts can disrupt native ecosystems. "Eucalyptus" may have adverse effects on local streams due to their chemical composition, and their dominance threatens species that rely on native trees. Nevertheless, some native species have been known to adapt to the "Eucalyptus" trees. Notable examples are herons, great horned owl, and the monarch butterfly using "Eucalyptus" groves as habitat. Despite these successes, eucalypts generally has a net negative impact on the overall balance of the native ecosystem.