Ecology Macroinvertebrate Study
revised May 2011


Please use the resources on this page to guide you in your measurement of the water quality of Lititz Run using the Hilsenhoff Biotic Index (Family HBI), The Ephemeroptera-Plecoptera-Trichoptera Index (EPT Index), and the Species/Taxa Richness Index (SPP Index). The .pdf file is a paper by Joy Perry that explains each of these measurements, and provides pictures of some of the most common groups of stream critters (in biology, we call a classification group of organisms a taxon (plural Taxa)), and other resources. What you are going to do is:
  1. Fill out a sheet for each of the three locations where you collected data. Code your locations as follows:
    1. 2011G1S1 (2011 Group 1 1), 2011G1S2, 2011G1S3. Use the appropriate group number for your group.
    2. Make each of your sites a pin on Google Earth, save as a .kmz file (NOT a .jpg). Name the file BantaMacro2011G1 (for Group 1), BantaMacro2011G2 (for Group 2), etc.
    3. Send your .kmz file as BantaMacro2011G1, or G2, G3, etc. to my CVSD e-mail
  2. Calculate Family HBI, EPT Index, and SPP index using the "Appendix A" sheet that I give you. Use the Perry article (Biotic Index Testing .pdf) or some other creditable resource to help you do this correctly.
  3. Refer to Page 11 of the Perry .pdf for a scale rating the quality of the water using your HBI, EPT, and SPP calculations. Include this rating at the bottom of each "Appendix A" sheet that you use for each site.
  4. Attach the pictures of each of the different taxa of critters that you collected to the "Appendix A" sheet for each site. Make sure that you have each photo labeled with what you identified the animal as. For example if you identified a critter as a chironomid larva, insert a text box on the photo that you turn in labeled "Chironomid."
  5. Calculate the stream flow using the measurements that you made in the field. Stream flow is simply:
    1. Stream width (in meters), times the average depth of the three or four measurements that you made (in meters), times the stream flow in meters/second. You can calculate the stream flow in m/s by taking 5 divided by the time that it took your float to more five meters. Width X Average Depth X Velocity (in m/s) = Flow in cubic meters per second m^3/s.
    2. This measurement can easily be converted to other units of flow using your choice of conversion apps.
    3. Write this calculation on the "Appendix A" sheet that corresponds closest with the location of your stream flow measurement in m^3/s, ft^3/s, and gallons per minute (g/min or gpm). This calculation doesn't need to be on your .kmz file.
  6. Before you turn in in your data, be sure to check out the data of the other five groups and compare what they found to your data.
  7. Finally include a written analysis of your assessment of the health of Lititz Run using the data that you gathered and analyzed along with any comparison data from other groups. For example, if all of the groups that you talked to identified a certain macro, then it is pretty safe to say that this is a regular critter of this stretch of LR. However, if your group identified one critter, that no other group identified, then it is possible that this critter is an anomaly to the data set and its presence is not necessarily a good indicator of the quality of Lititz Run. Don't be afraid to cite information from journal articles and class notes to support your points. This section of the writeup should be about a page typed, single-spaced.





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