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A well-known positive correlation between niche breadth and range size exists across a number of animal and plant taxa. A relatively more simple explanation, range size being connected to differing dispersal abilities, was recently presented for passerine birds. Unfortunately, respective datasets are not easily available for other taxonomic groups. We circumvented this problem by developing a simple dispersal index, incorporating niche information (body size, litter size, preferred habitats of adults and offspring, ecotype of adults) which can be collected straightforwardly for most animal taxa. We tested this dispersal index for species which are generally considered poor dispersers, amphibians. Our results from West Africa revealed a positive correlation between the dispersal index and range size (p < 0.001). Our index can easily be transferred to and tested with other taxa. Furthermore, our results suggest one possible way of integrating information on dispersal abilities in niche modelling (distribution modelling) processes which assess the impact of climate change on future species distributions.