Discerning the status of a rapidly declining naturalised bird: the Golden Pheasant in Britain

Abstract

Whilst many introduced non-native plants and animals become naturalised or even invasive, others fail to persist. Golden Pheasants (Chrysolophus pictus) have occurred in multiple regions outside of their native China, with the largest populations establishing in the United Kingdom. Now very rare in the UK, ongoing releases make its continued ‘wild’ status dubious. The Golden Pheasant in Britain provides a case study of an introduced species that at first appeared to thrive before declining to the point where no viable wild populations remain. Here, we outline the history of Britain’s Golden Pheasants before describing their current status. To do so, we reviewed the relevant literature, engaged in personal communications with rural staff and birdwatchers, and carried out a survey of a putative remnant population. We conclude that there are 37–40 ‘wild’ Golden Pheasants left in the UK, within two regions (both populations are dependent on human management via supplementary releases, food provision, or predator control, and therefore can no longer be considered to be truly naturalised as of 2023). This represents a significant decline from a 1993 UK population of 1000–2000. There is no evidence to suggest that Golden Pheasants persist in the UK as a self-sustaining population in 2023. We use this case study to discuss the issues associated with determining whether non-native populations are viable in the long term, and situations where apparently successful colonists then decline to extinction.