User: | Open Learning Faculty Member:
My first visit to get my five samples did not go well. I knew going in that it was going to be tricky, and it was. Sampling in the deeper water was difficult, even with a long aquatic net. The samples were dirty and difficult to count. Even with the extended reach, I knew I was disturbing the water too much and mostly likely scaring insects away. It was a lot of fun though, haha!
A new plan came to mind, and my second visit went much better. I decided to run a transect line 3’ from the shore, marked every 4’. Along the shore the plant density varies from no plants to very dense, and not in a predictable pattern. I cut the bottom off a five-gallon bucket and placed that down at the transect marker. Because I wasn’t too far from shore I was able to do it without disturbing the water too much, and it kept the insects contained. The bucket is white and water quite clear, but it was still too difficult to count without taking a water sample. I lightly disturbed the water with the net so the insects would swim up out of the plants. I tried to do it in a circular pattern for a three second count (so each is roughly uniform), and then removed the sample with a canvas net. I then placed it into a white bucket so it’s easy to see the insects. I realize I am not getting all the insects in that sample space, but hoping for a representative sample. I found the best way to count the insects was to focus on each insect species separately. The plants were easy to count after the insect sample was out. This plan came about with a lot of trial and error that day. I feel like this is the best I can do with the resources I have. The one thing I will do differently is rather than taking the samples in a line, I will do transect #10 then #5, #9 then #4 etc., to reduce scaring neighbouring insects away from the next sample area. Also, I can’t return any insects to the pond until I am finished so I don’t double count!
My predictor variable is plant density, and my response variable is number of aquatic insects. My initial data does show more insects in the denser plant areas. I noticed one type of insect only appeared in the samples with plants. It isn’t the best representative sample as the majority of them had no plants, and one landed on top of a big rock. But the rock sample had more insects than the two samples with no plants! I also recorded the number of different insect species within each sample:
very good demonstration of adaptability!