Interactions between non-native parrot species their recipient environments

Resumen

Biological invasions are amongst critical causes of biodiversity loss around the world, although interactions between invasive species, native biota and recipient environment are mostly unknown. Their identification may show how certain invasive species are able to establish successfully in novel environments and which potential ecological impacts threaten native biota. However, both interactions and their potential impacts are usually overlooked, especially in first stages of invasion, because they may arise between unexpected interact species as well as their detection depends of long-term studies. Parrots (Order Psittaciformes) are one of the groups most affected by international wildlife trade due to their appraisal as pets, consequently, 16% of parrot species present populations established out of their native range. Between non-native parrots, rose-ringed (Psittacula krameri) and monk (Myiopsitta monachus) parakeets are the most successful to establish and invade novel environments, even though numerous introductions have occurred in more than forty countries worldwide, their biotic interactions and impacts are poorly known. In this thesis, we combine different observations (behavioral, spatial distribution, environmental and population) to assess the role of different biotic interactions and their resultant impacts that arise between a total of X non-native parrot species (mainly rose-ringed and monk parakeets), recipient environment and biota. Our results show that non-native parrot species develop a wide range of biotic interactions (e.g. interspecific competition for nesting sites, facilitation of limiting resources and animal-plant mutualisms) that may threaten or benefit several coexisting species, both native and non-native. Thus, the emergence of adaptive behaviors (e.g. nesting association and innovation) in non-native parrots allows for overcoming barriers from recipient environment, such as biotic resistance and scarcity of limiting resources, or obstacles during their first stages of establishment (e.g. Allee effects). Overall, the wide analysis and study in long-term of biotic interactions here performed shows their importance as one of key mechanisms for success of establishment and invasion process in non-native parrots species. Moreover, their associated ecological impacts are a risk for native species, especially threaten species, hence, the implementation of efficient management plans is urgently necessary to conserve the biodiversity. Key words: Psittaciformes; biological invasions; interspecific competition; biotic resistance; commensalism; behavioral innovation; facilitation; hybridization; Allee effect; animal-plant mutualism; seed dispersal; zoochory; impact; eradication; management plans; population viability