Temporal changes in fish assemblage from the impingement data at the second nuclear power plant, northern Taiwan

Abstract

The main purposes of this study are to find out the temporal fluctuation of marine fish community based on impingement data collected at the Second Nuclear Power Plant in recent years (September 2000 to May 2004), and to compare the recent fish community structure data to that of an earlier period, around 14 years ago (July 1987 to April 1990). Comparison of the data collected recently to that collected 14 years ago showed that there were no yearly or monthly differences. However, the community structures reflected by clustering dendrograms or MDS ordination plots were quite different between earlier and recent years. This difference is likely due to the drastic changes in the dominant species. Fourteen years ago, the most dominant species was mullet (Mugil cephalus), but now, it has changed to lower economic species like rabbitfishes (Siganus fuscescens) and spiny puffer (Diodon holocanthus). This phenomenon might reflect the declination in our fishery resources due to overfishing; a trend especially clear in those species with higher economic values.