The Biological Monitoring Method


Although a wide variety of sampling techniques and equipment exist, for the purposes of the biological monitoring method, the "kick seine" or dip net technique is employed. This collection technique provides an uncomplicated and inexpensive means of sampling riffle areas for macroinvertebrates that can easily and quickly be learned.

The basic equipment for stream quality assessment consists of:

  1. a four-by-four foot nylon screen mesh seine,
  2. a pan or paper plate,
  3. the macroinvertebrate identification sheet,
  4. the monitoring assessment report form.

Once the collected organisms have been transferred to a surface where they can be clearly observed (plastic box, paper plate, or the upper clean portion of the seine), they are grouped and identified, and the information entered on the Stream Quality Assessment Form.

When the sample analysis has been made as to the kinds and approximate numbers of macroinvertebrates, a stream quality assessment is made in accordance with the procedures listed next. If the stream quality rating is "excellent", "good", or "fair", no additional sampling is required. On the other hand, should the stream quality rating fall in the "poor" classification, another series of collections should be made. If the stream quality rating again indicates "poor" quality conditions, the action procedure can be employed, in an attempt to locate the pollution source.

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