The Arrival and Spread of the European Firebug (Pyrrhocoris apterus) in Australia as Documented by Citizen Scientists

Abstract - We report the recent introduction and spread of the European Firebug (Pyrrhocoris apterus) in Australia, as documented on the citizen science platform iNaturalist. The species was first observed in December 2018 in the City of Brimbank (Melbourne, Victoria) and has quickly expanded into 15 adjacent municipalities, including areas in Metropolitan Melbourne and regional Victoria. Records of the European Firebug in Victoria are rapidly rising, with a current tally of almost 100 observations, as of July 31, 2021. The case of the European Firebug in Australia showcases the key role that citizen scientists are playing in the early detection of introduced species and in documenting their expansion across their non-native range. Citizen science presents an exciting opportunity to complement biosecurity efforts carried out by government agencies, which often lack resources to sufficiently fund detection and monitoring programs given the overwhelming number of current and potential invasive species. While the European Firebug has the potential to become a nuisance pest, negatively impacting both ornamental and indigenous plants, the ecological consequences of the rapid range expansion of the species in Australia and other parts of the world are currently unknown. We propose that future studies should be conducted to understand and quantify the effects of the species on Australian ecological communities and production industries. Given the range expansion patterns of the European Firebug worldwide, their adaptation ability, and future climate scenarios, we suspect the European Firebug will continue to expand its range beyond Victoria to other urban environments and regional areas of Australia, New Zealand, and the South Pacific. We believe that most of the knowledge about how this expansion continues to unfold will be provided by citizen scientists contributing observations in or around urban areas.