|梅蘭林道地區水鹿(Cervus unicolor swinhoei)與山羌(Muntiacus reevesi micrurus)食物品質與族群的季節變化
Seasonal Changes of Food Quality and Population Dynamics of Sambar (Cervus unicolor swinhoei) and Muntjac (Muntiacus reevesi micrurus) in Mei-Lan Trail Area
研究生：梁又仁 Liang, Yu-Jen
指導教授：裴家騏 Pei, Chai-Chyi
本研究利用糞便氮元素含量（FN）來探討水鹿（Cervus unicolor swinhoei）和山羌（Muntiacus reevesi micrurus）在南台灣中海拔森林中食物品質的季節變化，以及以自動照相機和水鹿糞便計算，探討這兩種鹿科動物的攝食品質、氣象因子和族群量之間是否存在季節間的相關。
Seasonal variation in food quality and population size of sambar deer（Cervus unicolor swinhoei）and muntjac（Muntiacus reevesi micrurus） in a mid-elevation forest in southern Taiwan were studied using fecal nitrogen (FN) content analysis, camera trapping and pellet-group counting.
The results show that the fecal nitrogen contents of sambar and muntjac varied throughout the year in Mei-Lan Trail. Sambar's FN highest peak appeared in autumn and winter and lowest in spring. Their FN content aligned with the seasonal changes of nitrogen content in grasses. Sambar consumes higher proportion of grasses in both autumn and winter. Muntjacs, on the other hand, showed its FN peak in summer, and lowest in winter, which significantly correlated with the seasonal variation of nitrogen content in forbs and shrub. These two kinds of food items were apparent the main food resource for muntjac in the study area. Although the food quality may be sufficient for the two cervids in Mei-Lan trail whole year-round, muntjacs might be able to acquire forages better in quality than the Sambar.
Sambar’s abundance did not differ between primary and secondary forests in the present study, which might because of the sambar population has larger home range and the same population covered both study sites of the two forest types. The abundance of muntjacs, however, is higher in the secondary forest, probably due to its abundant food resources. Present study also showed that the variation of food quality did not affect the number of deer used the study area both in dry and wet season. The number of deer used the study area, however, were positively affected by higher precipitation and temperature. Therefore, compared with the food quality, the quantity of fresh food availability may be a more important factor to affect the use of the habitat by deer.
The study area was apparently a wet season range for male sambar deer when the food supply are abundant, females rarely used it. The moderated hunting activity presented in the study area might cause their low utilization of the area, because female deer tends to stay in safer habitat so they can calve and lactate. Male sambar deer left the study area during dry season was must likely for searching for mates. In contrast, muntjac population was stable during the study period, non-seasonal breeder, larger population size and abundant food resources in the study area were probable reasons.
Keywords：Camera trapper, fecal nitrogen, pellet-group count, population size, sex ratio, sexual segregation