Van der Loop, Janneke M. M., et al. 2023.
The invasive Crassula helmsii is rapidly expanding in Europe. Several ecological effects are described, most of which focus on ecosystem functioning and native vegetation but rarely on fauna. In North-western Europe, C. helmsii often invades the breeding habitat of endangered amphibians, such as Epidalea calamita. The spawning rate, egg survival and the speed of larval growth of this toad species in relation to the presence of C. helmsii were studied. In order to unravel causal mechanisms, effects on natterjack toads were related to the effects of C. helmsii presence/absence on temperature and chemical properties of the water.