Benthic Macroinvertebrates in Chimacum Creek
(Procedure)
bug geeks
(at the beginning of the experiments)
Sarah Rosie Tasha
Problem:
Is Chimacum Creek polluted or not?
Hypothesis:
I believe the waters of Chimacum Creek are moderately
polluted.
Experiment:
Procedure:
I. Materials:
-meter
tape to identify location
-500
micron mesh Suber sampler
-
(2) 500 micron mesh sieve
-waders
(for each person)
-flagged
weight to identify sample location
-isopropyl
alcohol
-1
liter squirt bottle for isopropyl alcohol
-garden
trowel to disturb substrate
-stop watch
-
(2) white buckets to empty sample from suber
-tweezers
-large
cup to rinse invertebrates of surer
-plastic
spatula
-water
proof paper
-pencil
-permanent
marker
-grease
pencil
-screw
top vials
-Ziploc
bags
II. Step-by-step instructions
1. Locate steam reach to be sampled. Find a riffle (a fast moving water
over rock or cobble substrate, surface should be
broken) near the middle of the stream. Riffle should be long enough to collect
three samples in. Ideal sampling locations consist of rocks 5-10 cm in diameter
on top of pebbles.
2.
Collect the samples in the main flow. All three samples should have similar
depth, flow and substrate .Start the sampling
downstream and proceed upstream for the other samples. Record the exact
location of the samples.
3. Get into a team 2-4 people
a. Place the Surber sampler on the selected spot with the opening facing
upstream. Have one person hold the net on the creek bottom.
b. Lift some of the larger rocks within the frame and
brush off any crawling or loosely attached organisms
so they drift into the net. Then place the rocks in the bucket.
c.
After removing the larger rocks, disturb the substrate
rapidly with the garden trowel for 2 min. non-stop. Do not dig deeper than 10
cm to loosen organisms in the substrate,
washing them into the net.
d. Slowly lift the surber from the water. Tilt the net
up and out, keeping the open end upstream. This will help wash the organisms into the reciprocal at the bottom. Drop a
weighted flag to mark the location of the sample.
e. On the creek bank empty the contents of the surber
into a large bucket. Rinse several tines over the bucket until no organisms remain. This step is very important so take
great care. Using magnifying glass and tweezers, remove invertebrates
from the rocks and net. Remove large debris such as sticks and leaves. Wash organisms from bucket into sieve to remove water.
f.
Use spatula to remove sample from sieve to a plastic vial. Fill Vial with
isopropyl alcohol. Put a label inside vial with name of sampler, date, location
and replicate it, also write location and date on the top of the lid. Place the
vial in a ziplock bag labeled with the same information.
g. Return to first sample location. Walk upstream to collect the next
sample. Leave another flag. Repeat this process once more for a total of 3
samples. Label each one, keeping them separate.
III. Drawings:
(Click here)
IV. Data
tables:
There
will be no data until March.
Conclusion:
The
hypothesis cannot be proven or disproved until March when the results come.
What went right?
We did very well with collecting the samples. Everything went smoothly and as
planned.
What went wrong?
When we were collecting the samples out of the jars to put onto the microscope
slide, the jar was spilt.
What would you change?
I would take more samples to make sure the information collected was more
accurate.
bug geeks
(at the end of the experiment)
Sarah Rosie Tasha
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