Statement of the Problem:
How do the Macro Invertebrates tell the water quality of the sites observed? The sites
observed had a bridge, store, and roadways around it. The West Branch Susquehanna
downtown Curwensville is the site that was observed for the water quality.
Hypothesis:
The water quality of the West Branch Susquehanna steam will be good water quality.
Materials:
Shoulder length gloves, waders, buckets, hand lens, magnifying glass, or field
microscope, tweezers, eyedropper, spoons, large shallow white pans, plastic sorting
tubs or ice trays, taxonomic key to identify aquatic organisms, calculator, kick net- fine
mesh/nylon net approximately 1 meter square with a 3-foot long supporting pole on each
side is recommended, aquarium nets for additional habitat sampling, a large white trash
bag, and a change of clothes if needed.
Procedure:
First gather all the materials that are needed, and then approach the stream that is being
tested. Next, measure the three individual sites out, 91 meters apart; get the kick net plus
waders, etc. on then approach the sampling site from the downstream end. It should be 41
meters upstream from any man-made objects. Then, position the net at a 45 degree angle
with the bottom of the net tight against the bottom of the stream. In addition to that then
disturb the substrate thoroughly with your feet toward the net, but remember if big rocks
were moved to move them back to where they were found. Then, remove the net with a
forward scooping motion. Next, take the net ashore to where people will classify the
Macro Invertebrates with a chart into the white dish pans. Lastly, record the data of the
Macro Invertebrates on a piece of paper to go over the results found, to determine the
water quality of the stream.
Results (Data):
The date the experiment took place on 10-12-10, the time 9:50 A.M. The
weather was partly cloudy, the air temperature 18ᵒc. The water temp was 14ᵒc
as well. The water had a ph. of 6.5, which is slightly acidic, and 18 students
had participated in this experiment. As said before when testing this area
there was construction and work zones near, bridges, and a store.
Collection results begin on the next page!
Group 1
RA
Group 2 Taxa
5
R
Alderfly Larva
(4.0)
300
D
Water Penny
Larva
(4.0)
Other Beetle
Larva
(4.7)
Damselfy
Nymph
(5.2)
Drangonfly
Nymph
(5.2)
Other True
Flies
(5.6)
Blackfly Larva
(6.0)
RA
Group 3 Taxa
Taxa
Dobsonfly
Larva
Hellgramite
(0.0)
Fishfly
Larva
(0.0)
Netwinged
Midges
(0.0)
Clubtails
(Dragonfly)
(1.0)
Stonefly
Nymph
(1.1)
Watersnipe
Flies
(2.0)
Caddisfly
Larva
(2.8)
Cranefly
Larva
(3.0)
Other
Mayfly
(3.5)
Crayfish
(6.0)
Primitive
Minnow
Mayflies
(7.0)
Small
Squaregills
(7.0)
Snails
(7.0)
True Midges
(7.0)
Aquatic
Sowbugs
(8.0)
Aquatic
Worms
(8.0)
Leech
(10.0)
2
R
Moth Flies
(10)
9
R
Scuds
(6.0)
Rattailed
Maggot
(10.0)
Other: (*)
Other: (*)
1
Fingernail clam R
and Spider
Other: (*)
RA
Abundance
Weighting Factor
Group 1
Group 2
Group 3
R (rare)
5.0
3.2
1.2
C (common)
5.6
3.4
1.1
D (dominant)
5.3
3.0
1.0
Pollution Tolerance Chart
Group 1
(Very Sensitive)
Group 2
(Some What Sensitive)
Group 3
(Tolerant)
2 (# of R’s) x 5.0 =10
2 (# of R’s) x 3.2=6.4
0 (# of R’s) x 1.2=0
0 (# of C’s) x 5.6=0
0 (# of C’s) x 3.4=0
0 (# of C’s) x 1.1=0
1 (# of D’s) x 5.3=5.3
0 (# of D’s) x 3.0=0
0 (# of D’s) x 1.0=0
Total: 15.3
Index Value for
Group 1
15.3
Index Value for
Group 2
6.4
Total: 6.4
Index Value for
Group 3
0
Total: 0
Index Value for
site
21.7
Water Quality Rating
Site
Score
Rating
?
>40
Good
21.7
20-40
Fair
?
<20
Poor
Graph of Macro Invertebrates Collected
Number of Macro Invertabrates
Collected in the Susquehanna
300
200
100
0
caddis fly dobson
fly
mayfly
cray fish
finger
nail clam
Conclusion:
The Macro Invertebrates that were found in the West Branch of the
Susquehanna River were very sensitive, meaning that the water quality is a
fair water quality. The highest quantity of Macro Invertebrates collected was
the Caddisfly Larva, with three hundred plus maybe more. The lowest
collected was the Finger Nail Clam, with only one was collected. There were
four different types of Macro Invertebrates that were rare, and one Macro
Invertebrate that was dominating. The dominating Macro Invertebrate was the
Caddisfly Larva. One thing that was learned in the experiment was that when
disturbing the ecosystem, watch if a big rock is removed away from an area to
always put it back because remember that these rocks were habitats and
home for the Macro Invertebrates. For future reference, when conducting this
experiment don’t walk through the upper sites to get the most downstream
sites, it will disturb the collection site. Also, make note to not squish the
Macro Invertebrates while identifying them it will kill them and make the count
inaccurate. In conclusion the water quality is fair and the Macro Invertebrates
collected during was very sensitive and some were somewhat sensitive.