Rose-ringed Parakeet Psittacula krameri Populations and Numbers in Europe: A Complete Overview.

Purpose: Alien species are considered one of the major causes contributing to the current loss of biodiversity. Over the past few decades, a large and increasing number of alien species have become invasive in many parts of the world. Their impacts range from competition for resources with native species to damage of urban infrastructure. In Europe, over a thousand alien species are now established, of which 74 are birds. Among 12 established alien parrot species in Europe, Introduction: The Rose-ringed Parakeet (RRP) Psittacula krameri (Scopoli, 1769) is the most abundant and widespread. Since the 1960's, RRPs have established more than 100 wild populations in several European countries. For Western Europe, long-term demographic data indicate the species has grown considerably in number, although some populations have failed to persist. Data: Is scarce and dispersed for countries in Central, Eastern and Northern Europe. Therefore, here we present detailed demographic data of RRP for 90 populations in 10 European countries. Furthermore, we present information on the status of the species in another 27 European countries, for which previously no data were published. Conclusion: Our synthesis reveals a positive demographic trend across the continent, although locally, some populations appear to have reached carrying capacity.