On 12/5/07 Students practiced identifying macro invertebrates from Mill Creek. Using a document camera, images from the specimen tray were projected onto the SMART Board for easy viewing by all students. Students used a dichotomous key to help them identify the aquatic macro invertebrates.

We think these images show an adult riffle beetle. We were confused on what we were seeing. It looked as though this organism was trying to wiggle out of the "stuff" surrounding it. It worked very hard and as we watched, more and more of it pulled out of the surrounding matter. We have lots of questions. Is this a riffle beetle? Why is it "stuck"?



We think this next image shows an isopod because of the number of legs and the way it moved on the bottom of the tray. There were quite of few of these in our sample from the creek.


We think these images show a scud because it was moving on its side.


We also thought we observed a water snipe fly larva but we weren't sure. We are wondering if a water snipe fly larva swims very fast because the one in the tray was constantly moving. It was very small and thin. It was hard to tell if it had any legs. We also saw 1 flatworm in the tray. Since we didn't have a great sample of different macro invertebrates, we really can tell much about the water quality. Isopods are tolerant of pollution, scuds are semi-tolerant, riffle beetles are semi-sensitive, and water snipe fly larva are sensitive to pollution.