Distribution and population development of introduced Ring-necked Parakeets Psittacula krameri in Britain between 1983 and 1998

Abstract

Capsule Of the three subpopulations, only the one west of London was increasing, with little spread. Aims To investigate the distribution and population dynamics of feral Ring-necked Parakeets in Great Britain. Methods County bird report records (from 1983–95) were collated and analysed to determine distribution and population trends. Roost counts were undertaken monthly from September 1996 to September 1998 to determine minimum population counts and trends. Results The parakeets were distributed in three subpopulations: west of London, southeast London and in Thanet, Kent. The total population increased during the period, with little spread, except for a slight westward range expansion. Flock size did not increase, and population growth was only apparent from maximum counts at communal roosts. The roosts were largest in the early autumn when, in each of the three years, minimum total population counts were obtained. The west of London population was large and growing, while the southeast London and Thanet populations were smaller and not increasing. The yearly total population counts were 1508, 1880 and 2060. Conclusion The population is still relatively small and range expansion is slow, suggesting that agricultural areas are not yet threatened by this potential pest species.