Biotic Indexing:
Testing the Waters of Green Lake
 If you drove by
Playground Park early one morning, you may have wondered
why someone was standing is the cold, rushing water with
a net in one hand and a notebook in the other. Catching
and sketching fish? No. Panning for precious metals? No.
Taking water samples for biotic indexing? Yes. And Tom
Eddy, a Green Lake High School faculty member, and high
school student Sara Beronja, believe the information they
gain by sampling the waters flowing into and out of Green
Lake might be as valuable as gold nuggets!
Biotic indexing is a research method used to identify
and estimate the numbers and sizes of living organisms
found in a certain area. In this case, Beronja was hoping
her net would provide a sample of the invertebrates found
in Green Lake’s outlet. Beronja, who has also done
biotic indexing in northern Wisconsin’s more
pristine waters, has found that her net rewards her with
fewer and smaller species when sampling green Lake’s
watershed.
" The greater the variety of invertebrates we
find living in these waters, the healthier the waters
are," Eddy said. "If Sara only nets planaria
and tubifex or bristle worms, this suggests that
conditions won’t support other food chains.
Diversity is good and its presence means that conditions
are good." According to Eddy, biotic indexing is one
tool to measure the health of a stream. "If
it’s a stream flowing into or out of Green
Lake," he continued, "it can tell us a great
deal about the lake’s health."
The Green Lake Sanitary District
(GLSD), with the
cooperation and support of the Green Lake Association (GLA), sponsors partners with Education. Charlie marks,
GLSD Administrator, said the goal of Partners with
Education is to provide equipment and tools to school
districts within Green Lake’s watershed for studying
lake ecology. "Sky’s the limit," he said.
"It’s up to teachers to work up a project. If
it ties into leaning about the Green Lake watershed,
chances are very good that we can offer them some
support." The school districts within Green
Lake’s watershed are Green Lake, Princeton,
Markesan, and Ripon.
Partners with Education will be promoting two more
projects this spring. The first involves raising beetles
for purple loosestrife control. The second will study
effects of carp on aquatic vegetation and shoreline
erosion.
Nancy Hill, GLA Presidents, said, "The GLA is
committed to the success of Partners with Education
because the program supports and re-enforces many of the
association’s programs and efforts. Our Pontoon
Classroom and the newly launched Revitalization of
Shoreland Vegetation Project (RSVP) have goals that in
the largest sense are very comparable to those of
Partners with Education – increased awareness and
education leading to better lake and watershed
stewardship. The younger we get someone to become
conscious of his or her role as lake steward, the
better," she said. For more information about
Partners with Education, contact Marks at the GLSD, (920)
295-4488. For more information about Pontoon Classroom or
RSVP, call Hill at the GLA (920) 294-6480.
Preserving the
Waters—Students monitoring water quality in Green
Lake tributaries
(Oshkosh Northwestern, April 25, 1999,
Patricia Wolff)
 Standing
keep-deep in Hill Creek, seventh-grader Patrick McConnell
scraped his net along the creek bed and scooped up a huge
load of muck and bugs.
"You wouldn’t believe all the stuff I got in
the first one," McConnell yelled excitedly to his
classmates and teacher, Tom Eddy. All were clad in hip
boots and waders as they worked with nets and basins in
the cold water of the creek on a recent afternoon.
No, they weren’t panning for gold. Far from it.
They were panning for "critters," as Green Lake
Sanitary District Administrator Charlie Marks calls the
process that is officially known as biotic indexing.
Students in four school districts within the watershed
of Big Green Lake are involved in a project called
Partners with Education. Students collect, classify and
record aquatic creatures in the eight tributaries of the
lake – Wurch’s Creek, Spring Creek, Roy Creek,
Puchyan River, Hill Creek, White Creek, Dakin Creek, and
Silver Creek.
Biotic indexing is a research method used to identify
and estimate the number and size of living organisms
found in certain areas. The information reveals details
that help in monitoring the quality of the lake its
watershed.
"Biotic indexing monitors the health of a
stream," Marks said. "Based on the critters you
find, you can get an idea of the health of a
stream."
The greater the variety of invertebrates found in a
lake’s tributaries, the healthier the waters are.
For example, certain creatures such as caddis fly larvae
are found in pristine waters, while creatures such as
leeches and black fly larvae suggest more polluted
waters.
"Diversity is good, and its presence means that
conditions are good," Eddy explained
The students didn’t find any caddis fly larvae
during their recent sampling at Hill Creek, but they did
find plenty of crane fly larvae, indicating a fairly
clean creek, Eddy said.
About 40 students from Green Lake, Ripon, Markesan,
and Princeton schools are involved in the stream
monitoring, an on-going project of the Green Lake
Sanitary District and the Green Lake Association.
After McConnell and other students hauled in their
samples, the students scrutinized the stuff they’d
collected from the creek, using illustrated guides to
help them pinpoint which creatures they had found. The
guides described which aquatic organisms are sensitive to
pollutants and which are tolerant.
"This is the part of my job I love," Marks
said. "Something like this is great to work on
because there are just no losers. We are getting valuable
information and the students are learning about the
lake."
He said the project also fosters a sense of
stewardship in young people, who are future property
owners.
The results of the sampling done by students each
spring and fall will be posted on the Internet, Marks
said, to establish a database at the Sanitary District
office.
"We want to track data year to year to identify
trends. We’ll do it at the same place each time so
that if a certain stream degrades, we can begin practices
that will help the water quality in that creek to get
better," Marks said.
"We’ll be building a case so we can target
our dollars to points where the water is the worst,"
he added.
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