Continental vs. Global Niche-Based Modelling of Freshwater Species’ Distributions: How Big Are the Differences in the Estimated Climate Change Effects?

Thermal response curves that depict the probability of occurrence along a thermal gradient are used to derive various species’ properties and abilities cope with warming. However, different responses can be expected for portions species range. We focus on differences in (TRCs) niche requirements four freshwater fishes (Coregonus sardinella, Pungitius pungitius, Rutilus rutilus, Salvelinus alpinus) native Europe at (1) global (2) European continental scale. ranges captured only portion range major minimum (Tmin), maximum (Tmax) average temperature (Tav) respective distributions. Further investigations model-derived preferred (Tpref), warming tolerance (WT = Tmax − Tpref), safety margin (SM Tpref Tav) future climatic impact showed substantially differing results. All considered either were under- or overestimated level. Our results highlight that, although analyses have an impressive spatial extent, they might deliver misleading estimates niches climate change impacts, if do not cover full ranges. Studies management actions should therefore favor whole distribution data analyzing environmental gradients.