Our Field Study
Ms. Ciampi's fifth grade class
did a stream monitoring with Friend's of the Fox River's coordinator
Ms. Sue Bennett. The students walked down to Tyler Creek which
is near our school. Ms.Bennett met them their with the equipment
necessary to do a complete biological monitoring of the stream.
The effects of pollution are reflected in macroinvertebrate (macro means seen by the unaided eye and invertebrate means without a backbone) population. Monitoring these populations provides a relative view of the overall quality of a stream at any given time. The greater the diversity of organisms the better the water quality. Each species has a specific pollution tolerance. Grouping the number of species found on a pollution tolerance index allows students to assess the water quality. If a majority of pollution tolerant macroinvertebrates are found and very few intolerant ones, then the students know the water quality is not very good.
Students donned wading boots and entered Tyler Creek with their catch nets. These are large nets that are weighted on the bottom. One student held the net and two students "bugalooed" in the creek to disturb the macroinvertebrates living on the bottom of the creek. Nets were then brought up to discover what had been captured. The students were pleased with what they found. There was much diversity, and in an ecosystem that means healthy.
Students classified these organisms
according to their characteristics and entered the number of each
species on a Pollution Tolerance Index. This is a data sheet on
which the students recorded the kinds of macroinvertebrates collected
and their relative abundance. The index is divided into Pollution
Tolerant Groups 1,2,3, and 4. These groups represent the different
levels of pollution tolerance. The higher the number, the higher
the tolerance to pollution. Students added the number of macroinvertebrates
in each group, and following the formula, arrived at a water quality
indexvalue. The day we were at Tyler Creek it rated excellent.