Biotic velocity identifies potential climate refugia beyond climate velocity estimates

We developed a biotic velocity–based framework to identify three functionally distinct types of climate refugia with significant conservation value at the regional scale: (1) in-situ refugia, where species assemblage can persist locally without spatial displacement (i.e., areas with mean forward or backward biotic velocity equal to 0), (2) stepping-stone refugia, where species can track shifting climates with relatively low forward biotic velocity, and (3) ex-situ refugia, which are areas that can be readily colonized by species from other regions due to low backward biotic velocity. This framework, which integrates species distribution models (SDMs), climate exposure metrics, and biotic velocity, was applied to four taxa (mammals, reptiles, birds, and amphibians) under two climate scenarios in the Middle and Lower Reaches of the Yangtze River (MLRYR), China.