Analysis of activity rhythm and prediction of potential suitable distribution of black muntjac ( Muntiacus crinifrons ) based on the ITCT and MaxEnt model

The black muntjac(Muntiacus crinifrons) is an endangered mountain Cervidae endemic in China. Its distribution is limited to hilly and mountainous regions in Zhejiang, Fujian, Jiangxi, and Anhui Provinces. A study was carried out to understand the effects of activity rhythm, suitable environmental temperature, and distribution of potentially adaptive areas. Fifty-seven LtlAcorn infrared-triggered camera-traps were installed in six sample areas(Xijianling, Daxikeng, Alpine wetland, Jiupanli, Zhufengxia, and Taohualing) of Suichang Niutou Mountain, Zhejiang Province, China to monitor black muntjac and other wildlife from January 2018 to January 2019. A total of 13,655 camera-days of data were collected, including 89176 photos and videos during the 12 months of data collection using the infrared cameras. Twenty-six black muntjac were counted, and the calculated relative abundance index(RAI) was 1.79. The highest quantitative value for relative qbundance index(RAI) was 3.85 in Taohualing and the lowest one was 1.27 in Jiupanli. The MaxEnt model was used to obtain the current potentially suitable habitat based on six environmental variables and 16 current distribution sites. The accuracy of the model was verified by a receiver operating characteristic curve(ROC). The results showed that the area under ROC curve(AUC) was 0.976, suggesting a perfect predictive power of the model. The statistical results indicated that the peak of seasonal activity was in summer, and the two peaks of daily activity appeared from 07:00 to 09:00, and 16:00 to 18:00. Temperature is one of the most critical environmental factors influencing the activity of black muntjac; the range of preferred temperature was from 18 ℃ to 28 ℃. Acicular-leaved forest was the primary food source for black muntjac, and the altitude of preferred habitat was from 1000 m to 1200 m. We use the MaxEnt model to predict the suitable habitat of black muntjac, and the results show that there were three mainly geographical areas in China. The area of unsuitable habitat was approximate 508019.38 km~2, which accounted for 95.13% of the total area. The area of suitable habitat was approximate 25980.62 km~2, which accounted for 4.87% of the total area. It was divided into highly suitable habitat(3700.73 km~2, 0.69% of the total area), medium suitable habitat(7552.51 km~2, 1.41% of the total area), and low suitable habitat(14727.39 km~2, 2.76% of the total area). The results of Jackknife test indicated that altitude, a