Movement patterns within an urban population of fire salamanders highlight the importance of conserving small habitat patches

Movement is an ecological process that affects individual fitness and population dynamics of species. Understanding movement patterns is crucial for the effective conservation of amphibian populations isolated by urban development. Here, we conducted a capture-recapture study over 6 years in a population of the fire salamander (Salamandra salamandra) inhabiting a 7.3-ha patch of forest and disturbed land-use types in an urbanised catchment north-west of Budapest, Hungary. We investigated relationships between movement distances and environmental, spatial and demographic parameters in order to understand how this species is able to persist in a relatively small and isolated habitat patch. We found that most movement was aggregated around a permanent stream and that movement distances were generally <= 200 m, with maximum distances of 925 and 707 m for males and females, respectively. Movement patterns within the population were best modelled using a negative exponential function characterised by infrequent long-distance movement. Males had substantially larger home range sizes than females and were predicted to have larger movement distances. Mean movement distances were predicted to be larger in disturbed areas in the upper stream catchment which included residential areas, compared with smaller movements in more natural forest near the stream. There was a positive relationship between mean movement distance and body condition. Our results suggest that this local population persists in a relatively small habitat patch because it provides a stable breeding site and suitable foraging and shelter microhabitats. Conservation of the local population requires protection of the structure, connectivity and quality of forest and stream habitats, and preventing urban development in the surrounding catchment.