Modeling Future Potential Distribution of Buff-Bellied Hummingbird (Amazilia yucatanensis) Under Climate Change: Species vs. Subspecies

Global climate change is associated with changes in precipitation patterns and an increase in extreme weather events, which might shift the geographic distribution of species. Despite the importance of this topic, information is lacking for many species, particularly tropical birds. Here, we developed species distribution models (SDMs) to evaluate future projections of the distribution of the widespread Buff-bellied Hummingbird (Amazilia yucatanensis) and for each of the recognized subspecies (A. y. yucatanensis, A. y. cerviniventris, A. y. chalconota), under climate change scenarios. Using SDMs we evaluate current and future projections of their potential distribution for four Representative Concentration Pathway (RCPs) for the years 2050 and 2070. We also calculated the subspecies climatic niche breadth to test the relationship between their area of distribution and climatic niche breadth and their niche overlap. Future climate-change models suggested a small increase in the potential distribution of the species and the subspecies A. y. yucatanensis, but the predicted potential geographic range decreased in A. y. chalconota and remained unaffected in A. y. cerviniventris. The climatic niche of A. y. cerviniventris contained part niche space of A. y. yucatanensis and part of A. y. chalconota, but the climatic niches of A. y. yucatanensis and A. y. chalconota did not overlap. Our study highlights the importance of correctly choosing the taxonomic unit to be analyzed because subspecies will respond in a different manner to future climate change; therefore, conservation actions must consider intrinsic requirements of subspecies and the environmental drivers that shape their distributions.