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Greenwich Time
Students check up on river insects
By Hoa Nguyen
Staff Writer
May 28, 2006
For the sake of learning more about water quality, Jeff Yates did a dance of
sorts in the Mianus River Friday morning.
As he stood in river currents that roared downstream past his thighs, Yates
jerked his arms about and teetered his upper body from side to side, looking as
if he might tumble into the 57-degree water at any moment.
But he didn't fall and he wasn't dancing. He was just using his entire body to
help shuffle his feet about the river bottom, working to dislodge rocks and
other materials. Two Eastern Middle School students held out a fine mesh screen
to catch the river debris as the current carried it downstream.
After about a minute, Yates and the students hoisted up the screen and made
their way back to the river bank. Littered about the screen were remnants of the
river bottom -- most importantly the aquatic insects that scientists use to
gauge the health of a river.
"If you see sensitive bugs, that means the water is pretty good," said Erica
Gerber, a science teacher who organized the outing to the Mianus River Park
where eighth-grade advanced science students conducted water quality
experiments.
Their job was to survey the aquatic life found at the bottom of the Mianus River
as well as perform experiments on the water itself, such as testing for
dissolved oxygen.
Too little oxygen indicates something is out of balance and could lead to the
die-off of certain aquatic creatures.
Eastern Middle School student William Newberry, 14, of Riverside, said that a
number of different things could cause low dissolved oxygen levels.
"A lot of the bacteria eats up the oxygen," he said.
"And the algae eats them up too," piped in Ryan Carr, 13, of Cos Cob.
While the results of the chemical tests will say something about the water, the
type of insects the students find on the floor of the river will tell them
whether creatures find the water healthy enough to live in.
The more creatures the students find, such as stoneflies, which are considered
particularly sensitive to environmental changes, the healthier the river is.
Gerber organized the program, recruiting volunteers from the Mianus chapter of
Trout Unlimited to help students identify the bugs. Gerber, who recently
returned to teaching in Greenwich after several years in upstate New York,
organized a similar study eight years ago.
Back then the river received fairly high marks and in a week, when results of
the students' tests are analyzed, she will be able to compare the data to the
earlier study to check for changes.
With several groups of students spread across different parts of the Mianus
River Park, Gerber rode a red and blue mountain bike as she moved between
groups, checking up on their progress.
In one group, Yates -- a Trout Unlimited volunteer -- and three students
identified the insects by placing their face mere inches from the screen they
had used to trap the bugs. The students used paintbrushes to push about the
debris, looking for movement.
"You just have to look for stuff moving around," said Ethan Tollin, 13, of
Riverside, who was in a group with fellow students Nick Li and Andrew Fraser,
both 13.
In one hauling, the net caught 62 insects, nine of which were stoneflies, a
dozen were mayflies and nearly two dozen were caddisflies -- all indicators of a
healthy habitat.
Trout Unlimited, whose members fish the Mianus River and depend on its health,
are eager to help the students, not only because their results hold practical
value, but because doing the work will help groom a new generation of
conservationists, said Don Walton, a member of the group's board of directors.
"Somebody out of this group will pick up the torch and carry it," Walton said.
Copyright © 2006, Southern Connecticut Newspapers, Inc.
