Jiří Patoka

Invasive species are one of the main causes of biodiversity loss worldwide. Pet trade is a well-known pathway for the introduction of non-native species. Prevention is the most effective, least time-consuming, and least financially demanding way to protect biodiversity against the spreading of invasive species. The main part of prevention is the early detection of a potentially high-risk species, as well as the successful implementation of prevention strategies in legislation and practice. This study summarizes the pre-introduction screening of pet-traded terrestrial gastropod species and their potential occurrence in the EU territory. Based on the list of species traded in the Czech Republic, one of the most important global hubs of the pet trade, 51 species (49 snails and 2 slugs) were analysed. Due to a lack of certain native occurrence data, only 29 species (28 snails and 1 slug) from 10 families were modelled using MaxEnt software. Twenty species from seven families have potential occurrence in the EU territory. Based on MaxEnt modelling, we considered the following species to be high-risk candidates for the EU: Anguispira alternata, A. strongylodes, Laevicaulis alte, Megalobulismus oblongus, Rumina decollata, and R. saharica. Based on this estimation, we present considerations with which to further improve the risk assessment and recommend continuous monitoring of the pet trade market.