Movement of Fish Larvae with Tidal Flux in the Tanshui River Estuary, Northern Taiwan

為了瞭解仔魚的數量變動與潮汐週期之關係。利用兩種採集網於臺灣北部淡水河口進行24小時的連續採集，同時測定流速、水深、透明度、鹽度、pH及溶氧等環境因子。多數仔魚屬於河口依賴型的海洋性種類。仔魚的種類組成及數量隨季節而改變。春季以日本鯷（Engraulis japonicus）為主，夏季以小砂丁魚類（Sardinella spp.）為主，秋季以刺公鯷（Encrasicholina punctifer）為主，冬季以泰來海鯰（Arius thalassinus）為主。大部分種類為後期仔魚階段，河口域扮演著哺育場的功能。淡水河口屬於半日週潮，在一天的兩次漲潮中，仔魚的高峰只出現一次，高峰出現時間與24小時的明暗週期無關。仔魚的發育階段及體長組成，表底層之間無顯著性差異，但兩次漲潮有顯著性差異；顯示仔魚均勻地分布於水層中，但兩次漲潮的仔魚來自不同魚群。

關鍵字

仔稚魚；群聚構造；移動行為；潮汐；淡水河口

並列摘要

Movement of fish larvae in relation to tidal flux in the Tanshui River estuary was studied for 4 seasons during 1989 and 1990. The dominant species were Engraulis japonicus in spring, Sardinella spp. in summer, Encrasicholina punctifer in autumn, and Arius thalassinus in winter. The estuary had 2 flood tides daily, but the larvae were abundant only at 1 of the 2 flood tides. The timing of occurrence of peak abundance was independent of the diel period of light and dark. Size and stage compositions were not significantly different between surface and bottom water layers (p ＞ 0.05), but were significantly different between 2 successive flood tides (p ＜ 0.01), indicating that larvae in the estuary are evenly distributed in the water column, and that the larvae in the 2 successive flood tides were perhaps from different shoals.

並列關鍵字

Fish larvae ； Community structure ； Movement ； Tide ； Estuary

國際替代計量

Movement of Fish Larvae with Tidal Flux in the Tanshui River Estuary, Northern Taiwan

全文下載

主題瀏覽