Trait-based extinction risk in Southeast European hoverflies (Diptera, Syrphidae)

Global warming has become an important issue in recent years because it represents a constantly growing threat to global biodiversity. It is anticipated that extinction risk due to climate change will increase for a large number of species in the future. Functional traits, such as habitat preferences or characteristics of the life cycle of the species, may affect the response of the individual species to climate change. Finding statistically significant relationship between individual traits and changes in the distribution of species indicates that these traits affect the ability of species to move their area of occupancy.
The aim of this study was to estimate the extinction risk for 44 hoverfly species in Southeast Europe (endemic to the area and native non-endemics) based on the predicted changes in the potential area of occupancy for two time periods (2041-2060 and 2061-2080), and to establish which functional traits are correlated with range changes. Functional trait data were obtained from Speight et al. (2015) and expert opinion. Species distribution models were used for estimating range changes, while the relationship between functional traits and estimated changes in range was tested using linear regression models and linear mixed effect models.
Results of both linear regression models and linear mixed effect models showed the existence of significant interdependence between defined functional traits of hoverflies and the estimated range changes for both analyzed time periods. In most cases, traits connected with changes in range size were larval microhabitat (concretely, root zone), period of flight during early summer and adult macrohabitat.