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 be easily and quickly learned.
The basic equipment for stream quality assessment consists of:
- a 4-foot by 4-foot nylon screen mesh seine
- a white plastic pan or white plastic plate
- the macroinvertebrate identification sheet
- the monitoring assessment report form
Once the collected organisms have been transferred to a surface where they can be clearly observed (plastic box, plastic plate or the upper clean portion of the seine), they are grouped and identified and the information is 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 following procedures. 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.
Main Biological Monitoring page
