Application of the organophosphate insecticide Abate three times (at about monthly intervals) to duplicate 0.04 ha earthen ponds at 18 g/ha (4 micrograms/liter) -- the recommended application rate -- and 180 g/ha (40 micrograms/liter) caused no mortality on blugills. In ponds treated with 18 g/ha fewer bluegill fry were produced than in control ponds, brain acetylcholinesterase (AChE) activity was not affected, and accelerated growth of both fry and adults appeared to result from heavy feeding on dead or moribund Diptera larvae that resulted from the first two applications of Abate. The routine use of Abate at the recommended rate should have little adverse effect on fishery resources.

Freshwater field tests are an integral part of the process of hazard assessment of pesticides and other chemicals in the environment. This book brings together international experts on microcosms and mesocosms for a critical appraisal of theory and practice on the subject of freshwater field tests for hazard assessment. It is an authoritative and comprehensive summary of knowledge about freshwater field tests, with particular emphasis on their optimization for scientific and regulatory purposes. This valuable reference covers both lotic and lentic outdoor systems and addresses the choice of endpoints and test methodology. Instructive case histories show how to extrapolate test results to the real world.

Research into ecotoxicology can be classified into three fundamental concerns: abiotic factors, which characterize the physicochemistry of environments; biotic factors, relating to biological structures and functions; and contamination factors, which define the modes of pollution of ecosystems. The most significant research methodologies currently being developed in aquatic ecotoxicology are presented, specifically experimental approaches in the laboratory

Report on activities in the Divisions of Cooperative Research, Cultural Methods Research, Population Ecology Research, and Population Regulation Research.