Conservation status of Southeast Asian natural habitat estimated using Galliformes spatio-temporal range decline

Abstract

Southeast Asia has arguably the highest biodiversity loss due to the high deforestation rate and hunting pressure. In the region, 55 species of the family Phasianidae can be found in all available land habitats from lowland plains up to high-elevation mountainous areas. As ground-dwelling birds, these species are sensitive to habitat disturbance and hunting pressure, making them ideal to evaluate the status of remaining Southeast Asian forest habitats. The aims of this work are, therefore, to define for each Phasianidae species: (1) the extent of forest cover, suitable habitat and large forest patches currently available in the region and their decline over the years between 2000 and 2018 (six estimated generations) and (2) assess the threats using a Bayesian Belief Network approach combining data on forest loss hotspots and hunting pressure. Moreover, we defined the spatial distribution of Phasianidae diversity hotspots and relative threats in the region. The results show that over the 18-year study period, the forest cover, suitable habitat and Phasianidae diversity in Southeast Asia declined overall. The remaining forest habitats currently have low species diversity and face medium to high threat levels from habitat loss and hunting pressure. Population monitoring and higher protection levels both inside and outside protected areas are essential for the species’ long term survival. We recommend using Phasianidae as indicator species to monitor the overall habitat conservation status in Southeast Asia.