Handpicking Macroinvertebrates; Three Methods Compared

Benthic samples were sorted by three methods: electrical stimulus applied to living organisms, preserved in rose bengal formalin solution, and preserved natural-colored. The rose bengal stained samples were picked most accurately and rapidly except in very low invertebrate concentrations where the electrical stimulus was more efficient. Naturalcolored samples had the least accurate retrieval and were picked at a rate intermediate to the other two methods.