stylistic:tone, structural:scholar_edition
Feral populations

Escaped parrots of several species have become established in the wild outside their natural ranges and in some cases outside the natural range of parrots. Among the earliest instances were pet red shining-parrots from Fiji, which established a population on the islands of southern Tonga. These introductions were prehistoric and red-shining parrots were recorded in Tonga by Captain Cook in the 1770s. Escapees first began breeding in cities in California, Texas, and Florida in the 1950s (with unproven earlier claims dating to the 1920s in Texas and Florida). They have proved surprisingly hardy in adapting to conditions in Europe and North America. They sometimes even multiply to the point of becoming a nuisance or pest, and a threat to local ecosystems, and control measures have been used on some feral populations.

Feral parrot flocks can be formed after mass escapes of newly imported, wild-caught parrots from airports or quarantine facilities. Large groups of escapees have the protection of a flock and possess the skills to survive and breed in the wild. Some feral parakeets may have descended from escaped zoo birds. Escaped or released pets rarely contribute to establishing feral populations, as they usually result in only a few escapees, and most captive-born birds do not possess the necessary survival skills to find food or avoid predators and often do not survive long without human caretakers. However, in areas where there are existing feral parrot populations, escaped pets may sometimes successfully join these flocks. The most common years that feral parrots were released to non-native environments was from the 1890s to the 1940s, during the wild-caught parrot era. In the " parrot fever " panic of 1930, a city health commissioner urged everyone who owned a parrot to put them down, but some owners abandoned their parrots on the streets.