High habitat invasibility unveils the invasiveness potential of water frogs

Abstract

Determining the invasibility of habitats by alien species is crucial for understanding their spread potential, the habitats the most at risk and to implement adequate management actions. This is urgent for introduced taxa that show high invasion potential across broad geographical scales. We here assess these processes in invasive Pelophylax water frogs which are widespread colonizers across Western Europe and for which the invasibility of habitats remains to be quantified. Specifically, we used hierarchical occupancy models in a Bayesian framework to identify local-and landscape-scale features that can enhance occupancy of the most common invasive water frog, the marsh frog (P. ridibundus), in southern France. Water frogs were highly detectable and showed high occupancy across the invaded landscape. The invaders expressed a very broad habitat tolerance for both local-and landscape-scale variables while their invasion was facilitated by the occurrence of deep, permanent ponds with abundant aquatic vegetation and high sun exposure. Cross-validation showed a good transferability of models across space. The high invasibility of a wide range of habitats by Pelophylax water frogs is alarming and unveils their invasiveness, contributing therefore to explain their success of invasion over broad geographic scales.

Piecing the barcoding puzzle of Palearctic water frogs (Pelophylax) sheds light on amphibian biogeography and global invasions

“…More recently, molecular surveys aimed at tracing emerging biological invasions, notably by the marsh frogs (P. ridibundus complex), following uncontrolled introductions linked in part to the international trade for the frog leg industry (e.g., Bellati et al, 2023;Dufresnes et al, 2018;Dufresnes & Dubey, 2020;Holsbeek et al, 2008). Today, Pelophylax invaders are becoming a strong conservation concern, due to their broad habitat tolerance (Denoël et al, 2022), potential performances under future climate change (Padilla et al, 2023), fierce predation on native batrachofauna (Pille et al, 2021) and invertebrates (Pille et al, 2023), potential vectors of amphibian diseases such as chytridiomycosis (Baláž et al, 2014), and the risk to deregulate autochthonous hybridogenetic systems through hybridization and competition (Holsbeek & Jooris, 2010;Quilodrán et al, 2015).…”

“…Widely distributed from northwestern Africa to Japan, Palearctic water frogs of the genus Pelophylax offer great opportunities for large-scale studies in biogeography (Akın et al, 2010;Komaki et al, 2015;Lymberakis et al, 2007;Nicolas et al, 2015) and invasion biology (Denoël et al, 2022). From a molecular perspective, new biogeographic paradigm for the Palearctic since the Paleogene, notably by attributing a prominent role to the dynamics of the Paratethys, a vast paleo-sea that extended over most of Europe.…”

“…Widely distributed from northwestern Africa to Japan, Palearctic water frogs of the genus Pelophylax offer great opportunities for large‐scale studies in biogeography (Akın et al., 2010; Komaki et al., 2015; Lymberakis et al., 2007; Nicolas et al., 2015) and invasion biology (Denoël et al., 2022). From a molecular perspective, Pelophylax may be the amphibian genus that has been the most studied in Eurasia over the past 60 years (Dufresnes & Mazepa, 2020).…”

Functional and temporal facets of predation by marsh frogs across the aquatic–terrestrial ecotone of ponds and implications in the context of biological invasions

“…Considering the non‐native nature of the studied marsh frog populations, their wide fundamental trophic niche combined with the substantial number of feeding opportunities in ponds and along their shores results in the high potential invasiveness of marsh frogs. A recent study demonstrated the invasiveness potential from a habitat selection perspective across the landscape (Denoël et al, 2022). The present work highlights that this invasion success could also be enhanced by the trophic generalism of marsh frogs.…”

“…A recent study demonstrated the invasiveness potential from a habitat selection perspective across the landscape (Denoël et al, 2022).…”