Abstract: [Objective]This study aims to understand the population biology, including morphological characteristics, sex ratio, age structure, and altitudinal distribution of Tragopan caboti, which would be helpful to make effective conservation plan.[Method]Three methods were used to survey population biology of the Cabot's Tragopans in the Jiangxi Wuyishan Nature Reserve according to the altitudes, vegetation types and human disturbance in the study region:1) Line transact surveys:From April 2004 to December 2014, seven transacts with a total length of 80 km were set. 2) Individual capture and marking:A total of 26 Tragopans were captured in February 2006, March 2007, and March 2008. 3) Infrared-triggered camera surveys:From April 2010 to August 2014, 82 infrared-triggered cameras were set. Each camera worked for at least eight months.[Result]1) In pre-breeding period, body weight of the individual male adults was 1 210-1 500 g (n=15) and the body length 470-600 mm (n=5); body weight of the female adults was 1 030-1 384 g (n=7) and the body length 390-492 mm (n=5). 2) Sex ratio:results varied among the three methods of line transact, capture, and camera, with sex ratio (female:male) being 1:1.26, 1:2.25, and 1:1.60 respectively. Because of the causality and limited survey period of the line transect and capture surveys, the results of infrared-triggered camera surveys would be most reliable. 3) Age structure:we identified 131 individuals of Cabot's Tragopans based on photographs taken by cameras, including 47 adult males, 20 juvenile males, 29 adult females, 13 juvenile females, and 22 chicks. Combining with the mature age and expected lifespan, the population of Cabot's Tragopan in the region would have an increasing trend. Presuming one quarter of the total Cabot's Tragopans can be recorded by the infrared-triggered cameras, it was estimated that at least 100 breeding pairs were distributed in the region. 4) Altitudinal distribution:the Cabot's Tragopans mainly concentrated in the forests between 1 600-1 800 m altitudes monitoring by infrared camera, and over 90% of Tragopan photos taken by the cameras in the area. These cameras detected 40% of the total individuals recorded in the study region. About 60% of the Cabot's Tragopan photos in the altitudes of 1 200-1 600 m and 1 800-2 000 m. These cameras detected 52% of the total individuals. About 20%-40% of the Tragopan photos taken in the altitudes of 800-1 200 m and above 2 000 m. These cameras detected 8.4% of the total individuals. No Tragopans were detected by the cameras setting in the altitude of under 800 m.[Conclusion]Jiangxi Wuyishan Nature Reserve preserved the largest population of wild Cabot's Tragopan in China. Further monitoring of and research on the Cabot's Tragopans in this region will be helpful for protecting the endemic endangered species.

Key words: endanger pheasant, population of Cabot's Tragopan, sex ratio, age structure, altitude distribution, Jiangxi Wuyishan