Foraging diet of the two commonest non-native parakeets (Aves, Psittaciformes) in Italy: assessing their impact on ornamental and commercial plants

Abstract

Alhough the role as pest of the two most common invasive parakeets (rose-ringed parakeet, Psittacula krameri and monk parakeet, Myiopsitta monachus) has been largely recognized, nevertheless analytical data on foraging diet on cultivated plants are still scanty in non-native countries. Here, we carried out a revision about the impact of these birds on ornamental and commercial plants in Italy, both for urban and rural sites. Reviewing scientific papers, grey literature and personal observations, we obtained two species-specific checklists of edible plants. In this regard, we focused on plants of commercial interest in rural areas, implying a possible economic impact. We obtained evidences for 81 plant taxa belonging to 34 families (Rosaceae: the highest impacted). Almost all the evidences were related to ornamental species in urban parks and only a limited number of records refer to cultivated plants located in rural sites. Rose-ringed parakeet showed a significant higher percentage of foraged species when compared to monk parakeet. Nevertheless, when considering the plants of commercial interest in rural sites, monk parakeet showed a significantly higher number of records. Thanks to large distribution and easy detectability of these species, we obtained a large number of ‘grey’ data (local papers, unpublished reports and personal observations) that, although with a lower reliability, defined a first arrangement at large (national) scale. Future systematic field studies and citizen science actions will be necessary to obtain further quantitative data to support management and control strategies focused on these invasive birds.