Deadwood and amphibians in Europe: a preliminary assessment reveals a critical research gap

Deadwood plays a relevant role in nutrient cycles, contributes to soil formation, and provides food resources and microhabitats for many fungi, plants and animals. The association between the amount of deadwood retained on the floor of managed forests and the occupancy or abundance of amphibians is relatively well studied in temperate forest ecosystems in the northern U.S.A. and in Canada. However, no data has been compiled for European forest ecosystems, which cover approximately 35% of the total land area across Europe. Therefore, we retrieved all the peer-reviewed studies published in English that analyze the association between deadwood and amphibians, to better understand the taxonomic and geographic distribution of existing studies addressing amphibian-deadwood association. Out of the 10 retrieved studies concerning this topic, seven were performed in Italy, and one each in Estonia, Poland and the United Kingdom. Overall, only 15 species of amphibians were analyzed in relation to submerged, coarse or fine woody debris. Therefore, within the limits of English-language literature, our study identified apparent knowledge gaps in the association between amphibians and deadwood in European ecosystems. To fill these ecological gaps further efforts will be required, including integrating policy-relevant habitat classifications and well-conceived experimental or manipulative study designs.