Transcript Habitat Use By Larval Macromia and Hagenius

Anthropogenic Factors Effect On Invertebrate Population
Chase Oberfield
Advisor: Dr. McShaffrey
Figure 1: Sample Sites
Introduction
Discussion
Background
The monitoring of our natural environment is becoming an increasingly important
matter. With the human population reaching 7 billion, more and more wastes are being
dumped into the environment. It is important to continue to monitor the environment so
that the effects humans are having on it can be evaluated. One way of doing this is
through the use of biological indicators, or bioindicators.
Different organisms can be used as bioindicators, for the purpose of this study
aquatic invertebrates were used. Aquatic invertebrates are a good bioindicator due to the
fact that they are sensitive to many different materials (Walsh et al., 1982, 879). Thus the
presence or absence of these organisms allows the overall health of a particular
ecosystem to be evaluated. Dragonflies and their larvae are particularly useful in this
endeavor (Simaika, Samways, 2011, 371).
In this study aquatic invertebrates were used to assess the overall health of the
Kokosing River in central Ohio. The Kokosing River is a 57 mile long river that drains an
area of 482 square miles. The Ohio EPA rates the Kokosing River as one of the more
healthy waterways in Ohio (Ohio EPA). The Kokosing travels through a small city, as well as
many other areas where anthropogenic factors could have a potential impact.
Figure 1 shows the Kokosing River, as well as the sites surveyed. The map is oriented with north being
towards the top, and the flow of water being from west to east.
Figure 2: Quantitative Results: Relative Abundance at each Site.
Relative Abundance of Invertebrates
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Objective
To survey the Kokosing River with a focus on Odonata, as well as to determine if
anthropogenic factors have an effect on the diversity and abundance of aquatic
invertebrates.
Sites experiencing fewer anthropogenic factors will have a higher invertebrate
abundance and greater diversity.
Materials and Methods
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Invertebrates per m2
Hypothesis
Literature Cited
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Malmqvist B, Rundle S. 2002. Threats to the running water ecosystems of the world.
Environmental Conservation 29: 134-153
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Ohio EPA (Environmental Protection Agency). 2007. Biological and water quality study of
the Kokosing River watershed. EAS/2010-05-09. State of Ohio Environmental
Protection Agency. Division of Surface Water. Columbus, Ohio.
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Farm
Five sites were chosen based on their proximity to anthropogenic factors. All sites
were easily accessible, and previously sampled by the Ohio EPA in past surveys (Ohio EPA).
The sites were sampled during late summer 2012. Qualitative and quantitative sampling
methods were used. The qualitative testing was conducted by the use of a d-ring net, and
strictly odonata larvae were collected with this method. Quantitative testing was
performed through the use of a surber sampler, all aquatic invertebrates were collected
during the quantitative testing phase.
After collection the invertebrates were indentified. All odonata were identified to
species through the use of “Dragonflies of North America” by James Needham, Minter
Westfall Jr, and Michael L. May. The rest of the invertebrates were identified to order
(family when possible) via “Aquatic Insects of Wisconsin” by William Hilsenhoff. After
identification of the insects, the sites were then analyzed by the diversity, and abundance
of the collected specimens.
Mt. Vernon
Waste Water
Killduff
Jelloway
Figure 2 shows that the Farm, Killduff, and Jelloway areas, had the highest abundance, while Mt.
Vernon, and the Wastewater area had much lower relative abundance.
Figure 3: Number of Odonata Species at Each Site.
Walsh GE, Duke KM, Foster RB. 1982. Algae and crustaceans as indicators of bioactivity of
industrial wastes. Water Research 16(6):879-884.
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Acknowledgments
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I would like to thank Dr. McShaffrey for advising me on this project. I
would also like to thank Marietta College for providing the materials needed
to complete this study. I would also like to thank my parents for letting me
keep dead bugs in the house over the summer.
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Ninety-one odonata were collected from the 5 sites via the qualitative
sampling. There were 10 different species identified. Quantitative testing yielded
the relative abundance of invertebrates found at each site which can be seen in
Figure 2.
Simaika JP, Samways MJ. 2011. Comparative assessment of indices of freshwater habitat
conditions using different invertebrate taxon sets. Ecological Indicators 11(2011):
370-378
Number of Species at Each Site
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Results
The hypothesis that sites experiencing fewer anthropogenic factors will have a
higher invertebrate abundance and greater diversity is partially supported. The
abundance portion of the hypothesis agrees whereas the diversity portion is
inconclusive. Figure 2 shows that the Farm, Killduff and Jelloway area all have much
higher invertebrate abundance then Mt. Vernon and Waste Water. Literature states
that areas that have anthropogenic impacts such as habitat modification, and altered
water chemistry will have negative effects on invertebrate populations (Malmqvist,
2002, 135). Both of the sites with low abundance are subject to both of
these criteria, which could attribute to the low abundance found at these sites. This
same trend was not seen when species diversity was analyzed at each site.
Figure 3 shows the amount of species found at each site. The Farm, Mount
Vernon, and Jelloway sites all have similar amounts of species diversity.
However Killduff road has a significantly higher amount of species, and Waste Water
had no species found at all. Based on the variation in the data no solid conclusion
could be made. The variation seen in the data could be product of several factors. The
time of year the samples were collected were not optimal for many of the odonata, as
many of them have grown into adults and have flown from the water(Dr. Dave
McShaffrey, Personal Communication, 2012). Also there were relatively few samples
taken at each site.
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Farm
Mt. Vernon
Waste Water
Killduff
Jelloway
Number of Species at Each Site
Figure 3 Shows that the Farm, Mt. Vernon, and Jelloway all had similar species diversity. Killduff was the
most diverse site. No odonata were caught at the Waste Water site