Comparative Habitat Divergence and Fragmentation Analysis of Two Sympatric Pheasants in the Qilian Mountains, China

Abstract

Habitat fragmentation is considered a major threat to biodiversity worldwide. Two endangered species, the blood pheasant (Ithaginis cruentus) and the blue eared pheasant (Crossoptilon auritum), co-exist in a fragmented forest in the Qilian Mountains. However, how their habitats react to the fragmenting landscape remains unclear. Therefore, we carried out a field survey in the core habitat of the two species in Qilian Mountains National Park and used the MaxEnt Model to predict their potential distribution and to assess the protection efficiency. Then, we utilized a modified within-patch fragmentation categorizing model to identify how their functional fragmentations differentiated. The results showed that the habitat utilization of the two pheasant species was significantly different, with a potential distribution area of 18,281 km2 for the blood pheasant and 43,223 km2 for the blue eared pheasant. The habitat of the blue eared pheasant is highly fragmented with 27.7% categorized as ‘Interior’ and 49.3% as ‘Edge’, while the habitat of the blood pheasant is more severe with 2.1% categorized as ‘Interior’ and 50.4% as ‘Edge’. Analysis shows that large areas of habitat for the two pheasants remain unprotected by the Qilian Mountains National Park. The intense grazing and human infrastructure may have a large effect on the currently highly fragmented landscape. Future measurements are needed to alleviate this conflict.