Fish Kills in Ireland: An Analysis of Incidents in 1983 and 1984

Abstract

An analysis is presented of 200 fish kills recorded in 1983 and 1984. The reports which originated from various sources were corroborated by the water pollution officers of the Regional Fishery Boards. The incidents are evaluated by reference to similar information gathered by the Environmental Protection Agency of the United States of America. Shortcomings in the reporting of incidents include the lapse of time between the onset of a kill and its appraisal and the difficulties of establishing the facts retrospectively. The preponderance of trout among the mortalities might indicate a bias towards reporting incidents which involved this game species. The vast majority of kills occurred in rivers and about 65% took place in June and July, a pattern resembling that in the United States. Where the size of kill was recorded it averaged 269 fish, very small by U.S. standards. The average channel length affected by a fish kill was approximately 2.8 km (1.7 miles) (ranging between 0.01 and 25 km; 0.06 and 16 miles) and there was no relationship between the channel lengths and the numbers of mortalities.