Biological invasions - what are they and how are they caused?
Globalization, international trade and the endless transportation of people and goods around the world have greatly contributed to more and more species managing to reach areas far beyond their natural distribution (Hulme 2009; Seebens et al. 2017; Seebens 2019). A considerable number of these “introduced" species have managed to establish viable populations, and even become invasive in their newly invaded areas (Wang 2014).
These "introduced" species, also known as "alien" or "non-native". More than 14,000 alien species have been recorded in Europe, while in Cyprus their number exceeds 1,200 species. Some of them also become "invasive", threatening native biodiversity, and socioeconomy.
Invasive alien species are one of the major drivers of global biodiversity loss. Islands (such as Cyprus), are considered more susceptible to biological invasions, with invasive species even leading endemic island species to extinction.
Alien chalcid wasps
Up-to-date, no structured study has been conducted to sum up the global number of alien chalcid wasps. Since Chalcidoidea play a crucial role on classic biological control schemes, numerous species have been introduced outside their native range in order to mitigate insect pest populations and their adverse impacts. Nevertheless, many other species have been accidentally introduced around the globe, often following their either their host-insect or host-plant.
In Europe, more than 200 hundred alien species have been reported (Rasplus et al. 2010), although this number is expected to be much higher.
In Cyprus, at least 53 species have been reported until now (Demetriou et al. 2023) (this number is expected to be higher as well).
Checklist of alien chalcid wasps occurring in Cyprus