Week 3: 10/27/10

In today's observations, the organisms that were moving around are much smaller and slower than those that I observed during the first week. Now instead of the light brown color all of the organisms look completely transparent. There are once again the same amount of organisms on both the fern and the moss. This week there is not as much dirt on the bottom layer of the microaquarium.

The organisms I observed today:
Rotifers: there was a vast abundance of these, possibly from the food pellets that were introduced into the system this week.
Seed shrimp: I found around five of these organisms, and they were almost always on the bottom of the microaquarium.
Nematodes: these were seen throughout the microaquarium. The smaller ones were said to be younger than the long and thick ones. I saw one inside a plant bladder, which injests nematodes and dissolves them to use in the plant. (Shown below)

Aspodisca- this organism resembled the rotfers in its abundance. However appearance wise, the Aspodisca was rounder and smaller than the rotifer. It is known to have a clear mouth and I observed it moving quickly in random circular motions.

Sources for organisms:
-Dr. McFarland (rotifer, seed shrimp, nematode)
-D.J. Patterson. Free Living Freshwater Protozoa: A Colour Guide. ASM Press, Washington D.C. 2003.