Trophic plasticity and novel predator-prey interaction between two introduced snakes in a Mediterranean island

We report the first documented case of interspecific ophiophagy by the naturalised false smooth snake (Macroprotodon mauritanicus), observed preying upon the introduced horseshoe whip snake (Hemorrhois hippocrepis) in Mallorca (Balearic Islands, Spain). The event occurred in a suburban garden and was recorded with photographic evidence. Although M. mauritanicus may consume reptiles, interspecific ophiophagy has not been documented. This observation represents a novel trophic interaction between two introduced colubrids, likely facilitated by the increasing local abundance of H. hippocrepis and the ecological constraints of insular systems. This case, together with a previous report of avian predation on H. hippocrepis in Mallorca, suggests that both native or naturalised predators may be incorporating this introduced species into their diets. This finding contributes new data to the trophic ecology of M. mauritanicus and highlights the dynamic nature of predator-prey relationships in island ecosystems, potentially involving juvenile individuals due to size-related constraints.