Prediction of the Potential Distribution of Common Pochard (Aythya ferina) and Marbled Teal (Marmaronetta angustirostris) in Iran Under Future Climate Scenarios

Climate change is reshaping ecological communities worldwide, altering species distributions, abundance, and habitat suitability. We modelled the potential distribution of two duck species, the Common Pochard (Aythya ferina) and the Marbled Teal (Marmaronetta angustirostris), across Iran under current and future climate scenarios. Despite differences in optimal model performance (MaxEnt for Common Pochard and GAM for Marbled Teal), both species exhibited a convergent response to climate change, with a projected shift toward high-elevation montane wetlands under extreme scenarios. Both species showed: (1) loss of lowland habitats; (2) expansion into montane wetlands; (3) increasing suitability in the Alborz and Zagros ranges. Under the SSP5-8.5 scenario (2081-2100), representing an extreme climate pathway characterised by very high greenhouse gas emissions, both species exhibited substantial increases in climatically suitable habitat. The Marbled Teal showed an expansion of up to 3711 km2, while the suitable habitat of the Common Pochard increased to 21,671 km2, corresponding to gains of 167.6% and 137.3%, respectively. These results indicate that both species may possess comparable capacities to persist under future climatic conditions. However, the projected expansions appear to be strongly associated with the availability of high-altitude aquatic ecosystems, highlighting the crucial role of montane wetlands as potential climate refugia. Consequently, conservation planning should incorporate projections of future habitat suitability, with particular emphasis on the protection, restoration, and sustainable management of mountain wetland habitats to support the long-term persistence of both species under changing climatic conditions.