Final Observations

On Tuesday, November 11, I observed my Microaquarium for the last time. Here is a summary of what I saw:

Gastrotrich - counted 5
Euclanis - counted 12
Diatoms - several
Amoebas - counted 1
Vorticella - counted 3
Epalxis - several
Green Algae (Cladophora) - counted 1
Centropyxis - counted 1
Oscillatoria - counted 1
Calothrix - counted 1

These numbers may not accurately represent population sizes. I am very limited in my ability to spot organisms. Although the Microaquarium might appear small, it is a large amount of water for such small organisms. It is likely that I did not count every instance, and did not see some organisms at all that were present. It was especially difficult with organisms that live in or near soil, as the soil would often block clear images for identification.

The new organisms identified this week are pictured below.

Image 1: Oscillatoria, a filamentous cyanobacterium, identified from Handbook of Algae, pg. 378.

Image 2: a Calothrix cyanobacteria with visible heterocysts, identified from Handbook of Algae, pg. 427.

Image 3: Cladophora green algae covered in diatoms, as identified in Handbook of Algae, pg. 170. This algae is easily identified because it is one of only a few green algae that branch.

I learned a lot through these Microaquarium observations. While many people might have experienced declines in populations over time, my Microaquarium had plenty to observe every week. I would like to thank the University of Tennesse, Knoxville for the equipment and Dr. Ken McFarland for his invaluable assistance in identifying organisms every week.

Amber O'Malley

Week 3 of Observation

This is the week after food was added to the Microaquarium. There were several population changes to note this week.

There were many more rotifers, particularly Euchlanis. I also noticed a good increase in population of Tachysoma. I noticed at least 3 Vorticella, the largest population yet. I saw another gastrotrich that looked like the one from week 1 observation. The gastrotrich still evades identification. I also noticed 3 or 4 amoebas, the largest number again. Like last week, there were incredible amounts of diatoms. One type was organized in a long filamentous shape. 

Image 1: a diatom, Pinnularia nobilis, as identified from Turtox Class-Room Chart: Diatoms, Figure B. This was the only structure like this that I saw. I could not find any literature as to why the diatoms were like this, if they did this on their own, if they formed their own sheath or inhabited an empty shell left behind by some organism. 

There were a couple of new organisms I identified this week.

Image 2: Difflugia identified from Free-Living Freshwater Protozoa: A Colour Guide, p. 95, Figure 186. I only saw one of these.

Image 3: Asterionella as identified from Pond III: Photosynthetic Microlife. I saw several of these diatoms. Not all had 5 cells; some had less.

Until next week.