自動錄音機記錄巒大杉人工林區塊伐過程鳥類組成變化

Using autonomous recording units to record the changes of birds after patch cutting in Luanta fir plantation

本研究自2018年10月至2020年6月止，利用自動錄音機記錄大安溪事業區117林班區塊伐過程鳥類組成變化。研究期程區分成9個調查季，共記錄33科60屬約64種鳥類，包含22種保育類；整體鳥類群聚Sørensen相似性約0.71，不同調查季間的Sørensen相似性指數介於0.54-0.88。比對各調查季的鳥類群聚組成特性與對應分析排序圖，結果顯示研究區的季節改變可能造成鳥類群聚變化。將紀錄鳥種根據生態同功群及與森林關聯性分類的結果顯示，研究區內鳥類群聚棲地仍以森林為主，大多數鳥種於區塊伐面積增加後仍被持續記錄，顯示其對區塊伐過程的干擾具耐受度。本研究同時也記錄到偏好次級演替早期環境的鳥種，如臺灣叢樹鶯（Locustella alishanensis）等，顯示人工林在區塊伐後增加環境異質性，提供更多生態棲位。雖然自動錄音機資料有需要專業人員判釋種類，部分音檔難以辨認至種階級，且有較少鳴叫的鳥類不易被記錄的缺點，但其可以記錄夜行性鳥類的資料，並且大量節省調查人力支出。本研究認為使用自動錄音機可以有效瞭解林業作業活動對鳥類群聚變化的影響。

This study used autonomous recording units to record the birdcalls in 117th compartment of Daanxi working circle from July 2018 to March 2020. We divided the study period into 9 surveys with 3 months for each survey. A total of 64 species of 60 genera and 33 families was recorded, which included 22 protected species. The overall Sørensen similarity of bird composition was about 0.71, and the Sørensen similarity among surveys ranged from 0.54 to 0.88. According to the corresponding analysis, the seasonal migration of birds was probably the cause of the change in species composition of the community. We grouped bird species on the basis of their ecological guild and forest dependency. The results showed that the forest was still the main habitat in the study area. Most bird species were continuously recorded after the patch cutting area increased, suggesting that most species had good tolerance to the disturbance. However, bird species that prefer early secondary succession environments, such as Taiwan bush warbler (Locustella alishanensis), had also been recorded, showing that plantation increases environmental heterogeneity after patch cutting and provide more ecological niches. Although acoustics monitoring has shortcomings such as the need for professionals to identification, difficulty in identifying to the species level, and underestimate of species with fewer calls, it could record the data of nocturnal species and save personnel in the field. This study suggests that the use of autonomous recording units can effectively understand the impact of forestry management on changes in bird compositions.