Suitability of Wheel Ruts: Characterization of Overlooked Breeding Habitats of Alpine Newts

Abstract

The Alpine newt (Ichthyosaura alpestris) is sensitive to habitat destruction and alteration, and as a result there has been a decline in their populations across Europe. Due to historical landscape changes, the populations of Alpine newts drawn from lowlands and hilly areas have recently been primarily found in artificial habitats, such as wheel ruts. In some areas inhabited by the Alpine newt range, wheel ruts are the only available habitat for newt breeding, and thus the only one allowing the maintenance of their populations. However, our knowledge about this type of habitat is limited. Therefore, 60 wheel ruts in a hilly forested area in the Czech Republic were checked for the presence of Alpine newt larvae. Their characteristics were measured (conductivity, pH, dissolved oxygen, depth, water coverage, plants, presence of prey, hydroperiod). The presence of larvae was positively associated with higher values of pH, coverage of water plants, and the presence of prey. The strongest predictor was the hydrological stability of wheel ruts, and newts were found to prefer non-drying ruts. From the conservation point of view, this means that the suitability of wheel ruts for Alpine newts can be estimated quite easily. This can essentially be performed on the basis of visual inspection if it is carried out through the breeding season of newts.