Mapping habitat suitability of managed honey bees and native bumblebees to identify their spatial overlap

Pollinators, especially native bumblebees, are critical to maintaining ecosystem function and food production by enabling essential plant-pollinator interactions. Yet, these keystone species are increasingly threatened by habitat degradation, climate change, and competitive pressure from managed honey bees, whose expansion poses ecological risks. This is particularly urgent in regions where biodiversity conservation and commercial beekeeping intersect. Iran's Zagros and Alborz mountain ranges, recognized as global biodiversity hotspots, harbor rich native flora and support 26 species of native bumblebees essential to sustaining ecological integrity. These regions also underpin Iran's position as the world's third-largest honey producer, highlighting a delicate balance between pollinator conservation and apicultural expansion. While many bumblebee species are globally listed as vulnerable, endangered, or in decline, their conservation status and population trends in Iran remain undocumented, raising concern about unmonitored local declines. To address this gap, we applied an ensemble species distribution modeling approach integrating bioclimatic, NDVI, topographic, and anthropogenic variables to predict habitat suitability and assess spatial overlap between native bumblebees and managed honey bees. Results reveal high-suitability zones for native bumblebees in the Alborz Mountains, Azerbaijan highlands, and western Zagros. Although nationwide overlap is moderate, localized hotspots of intense co-occurrence, particularly in Alborz, signal zones of competitive conflict and ecological vulnerability. Most managed honey bees in Iran belong to Apis mellifera carnica, which is not native to Iran. The native Iranian honey bee is Apis mellifera meda. As non-native, high-density, human-supported species, managed honey bees may intensify pressure on native pollinators, especially under accelerating climate and land-use change. This study provides spatial evidence to guide conservation priorities and align biodiversity protection with sustainable apiculture across one of the world's most vital mountain ecosystems.