A LABORATORY ASSAY TO ASSESS AVOIDANCE OF CONTAMINATED SEDIMENTS BY THE FRESH-WATER OLIGOCHAETE LUMBRICULUS-VARIEGATUS

Responses of benthic organisms to contaminated sediments in the labora tory historically have been assessed as survival, growth, and reproduc tion. However, these responses do not include behavioral aspects of or ganisms, which also can influence species distribution and abundance i n benthic communities. This study documents avoidance behavior of the freshwater oligochaete Lumbriculus variegatus to contaminated sediment s in the laboratory, utilizing a chamber specifically built to facilit ate the measurement of this response. A number of field-collected sedi ments from sites with known contamination, several of which exhibited little or no toxicity in standard tests examining growth and/or surviv al, were evaluated. The oligochaetes exhibited marked avoidance to man y of the sediments, indicating the potential utility of this assay in identifying effects of contaminated sediments on benthic community str ucture.