Reproduction of common frogs, rana temporaria, in a managed conifer forest and bog landscape in Western Ireland

Landscape management schemes can have unanticipated effects on native species. While we tend to label habitat alterations as distinctly good or bad for specific species, it is not always clear what constitutes good habitat and what is low quality habitat. In many managed landscapes, there is a cyclical nature to these alterations, with some stages in the management cycle increasing suitability and others degrading it. In Ireland, afforested blanket bogs are managed to create a cycle of mature conifer forest alternating with a clear-felled landscape. These plantation forests have the potential to fragment naturally occurring amphibian habitat and reduce access to suitable breeding sites, though it is not clear how each management stage actually affects amphibian populations. We studied one of Ireland’s three amphibians, the European Common Frog (Rana temporaria), to identify if parts of these plantations contained good breeding habitat. We conducted our study in the west of Ireland, comparing breeding habitat availability and use among pools in mature plantation forests, clear-felled areas, unplanted blanket bogs, and roadside drainage ditches. Frog breeding use and reproductive output was highest in drainage ditches and clear-felled sites. Mature plantations had lower pool densities and spawn clump densities than either drainage ditches or clear-felled sites, and no larval development. Pools with high pH, large surface area, and high temperatures had the highest probability of spawn presence. Plantation forestry can be detrimental to Common Frogs, but applying sequential harvest strategies may allow this species to persist within plantations as habitat availability shifts over time.