A survey and risk screening of non-native ant species colonising greenhouses in Hungary

Abstract

Invasive species represent a severe threat for ecosystem health worldwide. With increasing global trade and ongoing climate change, monitoring non-native species and their hotspots of potential spread is becoming increasingly important. Invasive ants are one of the most problematic groups of organisms costing billions of dollars a year globally to control. Therefore, emerging ant invasions require more focused engagement to assess their extent, and effective measures to prevent the spread of non-native invasive species can be time consuming and expensive to implement. In addition to places with high commercial traffic, greenhouses are potential hotspots for non-native species as they can be entry points for invasions. However, the role of greenhouses in ant invasions is still understudied. In this study, an extensive survey of greenhouses in zoos and botanical gardens of Hungary was conducted to search for non-native ant species. The five species found in the surveys and an additional two known from Hungary were then screened for their risk of invasiveness in the country under both current and predicted climate conditions. Three species were found to pose a considerable conservation and economic risk for Hungary, and one is already present in the wild. Increased monitoring of greenhouses and other heated premises for the presence of non-native species and targeted chemical eradication are needed to prevent their spread. The risk screening method employed in this study can be applied to a wide range of terrestrial animal taxa, thereby providing a basis for developing more effective prevention and control strategies against invasive species.