Negative impacts of cultural monument restoration on the Common Wall Lizard population

Some animals successfully inhabit anthropogenic environments but are often exposed to negative impacts such as habitat destruction, disturbance and pollution. Lizards frequently occupy stone walls, abandoned buildings and cultural monuments, including fortresses, where crevices provide important sites for hiding, thermoregulation, and hibernation. However, urbanisation and restoration activities can negatively affect animal populations by restricting movement and dispersal and by reducing reproductive success, growth, and survival, potentially leading to population declines or local extinctions. The main objective of this study was to assess the impact of cultural monument restoration on Common Wall Lizard (Podarcis muralis) populations by analysing body condition index and population structure. The study was conducted at Kalemegdan Fortress, located in the urban centre of Belgrade, Serbia. This three-year-long research showed that at the locality Kalemegdan 1, fortress restoration caused local population extinction due to habitat destruction and the killing of lizards, with no evidence of lizards migrating to the neighbouring locality - Kalemegdan 2. Interestingly, lizards from Kalemegdan 1 consistently exhibited a higher body condition index than those from Kalemegdan 2, suggesting more favourable hibernation conditions at the former locality. However, body condition index values at Kalemegdan 1 showed a declining trend over the study period, likely as a consequence of restoration activities. Overall, the results indicate that restoration of historic fortresses can result in habitat loss and population declines in urban lizards. Given that urban populations are often small and fragmented, the absence of appropriate mitigation measures during restoration may increase the risk of local extinction.