emily welborn

My responsibilities for my internship with the National Park Service at the Whitman Mission were to take an inventory of the macro-invertebrates in the pond to assess its overall health. Ideally, I will be able to map out the organisms found in each sampling. In the future this map can be used to determine changes in health of the pond over time. Also, observations of organisms present indicate the current health of the pond.

Dr. Drabek was helpful in getting this project started by providing advice on the best procedure and supplying the tools necessary. He also provided a space in the laboratory complete with a microscope, guide books, and other materials necessary for correctly identifying as many organisms as possible. The tools he supplied to me were a shovel for digging up sediment and a sieve for collecting organisms from the sediment. Various macro-invertebrates were collected and stored in ethanol to be preserved and taken to the lab to be identified.

Unfortunately, Roger and I discovered that the bottom of the pond consisted of rocks making the tools not useful. Information about surveying aquatic ecosystems revealed that another possible location for collecting macro-invertebrates is in the roots of plants in the water, so the next step was to take some samples of plant roots. The bottom of the nearby stream consisted of sand and sediments that were much easier to gather. Since the stream supplies the water to the pond, this seemed like a valid place for collecting as well. From these two samples, I was only able to identify a few organisms. Of the materials I was given to aid in identifying organisms, they were only somewhat useful because of my lack of experience and knowledge in the field. From further research I discovered that most places that do biological surveys send their samples away for professional assessments.

From the obstacles I encountered and from talking with Roger at the Whitman Mission, we decided that I should keep taking samples just from the stream and identify as many organisms as possible. I could then determine what exact organisms I can identify and focus on those and their roles in the ecosystem and what they can reveal. Even though my original assignment involved the pond, this would also be a relevant survey because the stream supplies the pond with water.

Organism	Location	Significance
Midge	Pond Roots	Sign of Organic Enrichment
Limpet, pulmonate (lunged snail)	Upstream and downstream from inlet	Not as sensitive to pollutants because can get O2 from the air
Aquatic Worm	Stream inlet into the pond	Can tolerate low oxygen and high population in orgacially polluted streams
Clam/Mussel	Upstream from inlet	Good indicator of water quality, many can tolerate somewhat degraded conditions

The three areas that I took samples from did not range over a long distance of the stream. Therefore, the three locations most likely do not vary significantly in the quality of water. The conditions of this area of the stream can be determined by all of the organisms collected rather than looking at each individual section observed.

Based on the data I collected, I would define the habitat quality of the stream as half way between healthy and heavily polluted. Since two of these organisms (clams and aquatic worms) can tolerate polluted waters, this only shows that it is possible the water is slightly polluted but not a definite quality. However, in very healthy waters, many other macro-invertebrates should be seen such as mayflies and stonefly nymphs. I did not see any traces of either of these in the stream. This leads me to believe that the water is polluted to some extent, but the question is how much. Since few organisms thrive in very polluted waters, and none of these were found, it leads me to believe that these waters cannot be very polluted. Therefore, they must be somewhere in between healthy and polluted. Even though this classification is vague, this was the farthest I could draw my conclusions based on my data and my lack of experience in the field. Whatever the pollution content of the stream is, the pond is likely more polluted because of the nature of a pond. The water flows in and sits for a long period of time before it leaves and enters the stream again if it ever does. Therefore, these pollutants build up over time that entered from the stream increasing the concentration of organic enrichment and other harmful chemicals.

There are a few ways that I would change the procedure to this project if I were to continue with it. First of all, this internship should be spread over at least one full year because organisms have seasonal cycles so it is ideal to conduct a survey of the same location with each seasonal change. All of my samples were measured about the same time: during the month of October. Also, on the days that I took samples, I should have recorded the weather conditions. Then I could also take samples on days with varying weather conditions and compare those as well to eliminate one more factor contributing the organisms present in the ecosystem. I would also consider having a professional identify the organisms because I still am not sure if all of the organisms were identified correctly. This could greatly change the outcome of the survey because many organisms look alike but require drastically different habitat conditions to survive. Because of this, I don’t know how valid my research and conclusions are. Also, with the help of a professional, this project could be completed much faster and more efficiently than with just a volunteer.

Barbour, M. T., J. Gerritsen, B. D. Snyder, and J.B Stribling. 1999. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish, Second Edition. EPA 842-B-99-002. U.S. Environmental Protection Agency; Office of Water; Washington, D.C.

Engel, S.R. and J. Reese Voshell, Jr. “Volunteer Biological Monitoring: Can it Accurately Assess the Ecological Condition of Streams?” Fall, 2002. <http://www.vasos.org/Engel&VoshellAmerEnto2002.pdf>

“Macroinvertebrate Mayhem.” The Watercourse and Council for Environmental Education (CEE).