利用氣象雷達探討2005年秋季赤腹鷹過境恆春半島之模式

Use of Weather Radar to Study the Fall Migration of the Chinese Sparrowhawk on Hengchun Peninsula in 2005

鄭育昇(Yu-Sheng Cheng) ； 孫元勳(Yuan-Hsun Sun) ； 鄧財文(Tsai-Wen Deng)

《台灣林業科學》 21卷4期 (2006/12) Pp. 491-498

https://doi.org/10.7075/TJFS.200612.0491

摘要

本研究的目的在於利用氣象雷達影像探討2005年秋季赤腹鷹(Accipiter soloensis)過境恆春半島之時間分布模式、數量、路線以及鷹群結構，並與傳統地面調查比較。結果顯示：研究期間記錄到496個赤腹鷹群過境恆春半島，各鷹群的數量介於38~5,908隻之間，其中規模在1,000隻以上的鷹群，佔總鷹群數的10.1%，而半數以上的鷹群(53.4%)，規模介於100~499隻。經由估算，赤腹鷹總過境量達205,197隻，95%信賴區間：166,347~228,206隻。其中69.6%經由陸路，通過地面調查可視範圍進行遷徙；30.4%則經由海路，直接由恆春半島及蘭嶼間海域向南方遷徙。經由陸路及海路的鷹群，主要過境時段分別出現在07:00和10:00。各鷹群的長度及寬度則在0.75~11.64和0.25~1km之間。單日最大過境量出現在9月13日，數量達47,613隻。

關鍵字

猛禽 ； 遷徙 ； 鷹群 ； 墾丁 ； 都卜勒氣象雷達

並列摘要

The fall migration of the Chinese Sparrowhawk (Accipiter soloensis) through the the Hengchun Peninsula at the southern tip of Taiwan was studied using Doppler weather radar, and results were compared with traditional ground counts, to determine the temporal pattern, number, flyway, and flock structure in September 2005. In total, 496 flocks were located on radar images, with an estimated 38 to 5,908 hawks present in a flock. Sizes of most flocks (53.4%) numbered from 100 to 499 hawks, while flocks of ＞1,000 hawks comprised merely 10.1%. In total, an estimated 205,197 hawks, with a 95% confidence interval of 166,347~228,206 hawks, passed through the Peninsula in that month. Of these, 69.6% of the hawks flew via a land route, while 30.4% passed by a sea route which is between the Peninsula and Lanyu. The number of hawks flying by the land and sea routes peaked at 07:00 and 10:00, respectively. Hawk flocks ranged from 0.75 to 11.64km in length and 0.25 to 1km in width, respectively. The number of hawks was estimated to have reached 47,613 hawks on 13 September, the highest number for a single day that month.

並列關鍵字

raptor ； migration ； flock of hawks ； Kenting ； Doppler weather radar