Changes in the Fish Population in the Upper Ohio River following Temporary Pollution Abatement

摘要

The abatement of pollution in the upper Ohio River following closure of the steel industries on July 15, 1959, led to a marked improvement in water quality accompanied by a rapid increase in the variety and abundance of fishes. Collections of fishes with rotenone from the auxiliary lock chamber at Montgomery Lock and Dam yielded more than twice as many different kinds and more than five times as many individuals within 11 days after the beginning of the steel strike than comparable samples taken from the same area before the strike. The principal difference in species composition was the occurrence of “clean-water fishes” that invaded the previously polluted area, probably from nearby unpolluted waters.