Strontium Bands in Relation to Age Marks in Otoliths of European Eel Anguilla Anguilla

歐洲鰻耳石上之高鍶環與年輪之關係

曾萬年(Wann-Nian Tzeng) ； Kenneth P. Severin ； Håkan Wickström ； 王佳惠(Chia-Hui Wang)

《Zoological Studies》 38卷4期 (1999/10) Pp. 452-457

摘要

利用電子微探儀及光學顯微鏡，分析歐洲鰻耳石的高濃度鍶環與年輪之關係。結果發現來自鹹淡水的歐洲鰻的耳石，有很明顯的高鍶環出現，高鍶環的位置與年輪的位置一致。但是，來自湖泊者，則沒有高鍶環出現。推測高鍶環可能是鰻魚於冬季從鹹淡水迴游到高鹽度的海水時所形成的。由年輪的數目可以知道鰻魚的年齡。因此，由高鍶環的數目可以推測鰻魚在鹹淡水時的年齡及其迴游履歷。

關鍵字

歐洲鰻 ； 耳石 ； 鍶 ； 年輪

並列摘要

Higher-concentration strontium (Sr) bands and hyaline zones in otoliths of European eel, Anguilla anguilla (L.), from both brackish waters and freshwater lakes were examined by wavelength dispersive x-ray spectrometry on an electron microprobe and by visible light microscopy, respectively. The positions of higher-concentration (＞ 0.3 wt %) Sr bands and hyaline zones were identical in otoliths of eels from brackish waters; however, no corresponding higher-concentration Sr bands were discernible in otoliths of eels from fresh water. The higher-concentration Sr bands were deposited when the eels migrated from brackish water to high-saline seawater during winter. The number of hyaline zones in the otoliths corresponds to the age of the eel. Accordingly, higher-concentration Sr bands in otoliths can be used to determine fish age and migratory history in brackish waters.

並列關鍵字

European eel ； Otolith ； Strontium ； Annulus