Spirogyra

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Recently, the instructors at Brunswick took myself and another student to the ponds and showed us certain common elements that are important to proper pond management and care. One of the important things I learned was about filament algae, and the threat it poses to fish.

Pond with filamentous algae, at Brunswick Community College
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Filamentous algae, at Brunswick Community College
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Filamentous algae are microscopic algae that form colonies of “filaments” — hence the name. These algae are notorious for forming the large, pillow-like mats of algae that float on the surface of ponds. Common types found in Ohio include Spirogyra and Pithophora.
Disadvantages
As in the case with planktonic algae, high levels of nutrients can cause filamentous algae abundance to explode, especially in ponds lacking other aquatic plants, becoming so abundant that severe oxygen problems can result in the pre-dawn hours during July and August. Treating a severe filamentous algae problem in summer will almost certainly cause a fish kill. Ohio State University Extension Fact Sheet A-8-01, Winter and Summer Fish Kills in Ponds, provides insight into how these types of summer kills occur.
From Benefits and Disadvantages of Aquatic Plants in Ponds, Ohio State University Extension



Algae are primitive aquatic plants that differ from other plants in that they have no true stems, leaves or roots. They have a place in the overall food chain as they convert the energy of the sun into forms that can be used as a food source for other aquatic life. Algae also help to increase dissolved oxygen in water. Algae grow in both fresh and salt water systems. There are said to be over 20,000 different named species of green algae. Algae occur in three different basic forms. These are categorised as planktonic, filamentous and macrophytic.
Worldwide, there are over 400 different species of the genus Spirogyra. Spirogyra tends to show in ponds as a tangled pond scum. It is also called “water silk”, “silk weed” and “mermaid tresses”. On sunny days, the mats of spirogyra filaments usually float on the surface of the water. They are kept afloat by tiny bubbles of oxygen arising from photosynthesis. These algal mats then sink when the sun goes down and the process reverses as photosynthesis is reduced. As a result, the strands of Spirogyra consume oxygen for cellular respiration. Carbon dioxide is then produced as a waste product. Where there are thick algal mats present, large fluctuations in the dissolved carbon dioxide and oxygen levels in the water can occur. This can lead to rapid changes in the pH of the water that in turn can cause stress and even death to other organisms, eg fish, living in the water.
Blanket Weed and other Pond Algae

Spirogyra - A Filament Algae, magnified at +/- 40x











A Desmid and Spirogyra algae found in the pond sample.


A Cladoceran found among the algae sample.

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Proper Algae Plankton Identification

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Here's one example of the problems with identifying algae species, and I haven't really even began documenting what I'm seeing under the microscope.

To give an idea of scale, it's a grain of sand... and beside it sets the organism in question.

Three of them.

Going by the "Aids to the Recognition of Fresh-Water Algae, Invertebrates and Fishes," a brief 24 page paper which my instructor photocopied for me to use... the closest, is Merismopedia. But, that may be wrong. This species could also be, "Crucigenia rectangularis," both look practically the same.

Here's merismopedia.

Needless to say there may be others that look similar or near identical.

I've surfed the web, and really ran into some problems with species identification -- for that matter, proper classification into genus.

This was written by a biology instructor, in regard to the trouble I've had identifying species writes:

The proper way [to collect plankton] is to use properly calibrated and sized plankton filters.

I recognize the eagerness which you show in searching out and trying to identify the enormous range of things you can find. It is what is found in the best students; those truly interested in learning as opposed to those who simply want to get through the required laboratory exercises and go home. Unfortunately, there are not simple answers to questions, even "simple" questions like "what is this". Especially not when the sample comes from teaching aquaria that may be filled with all sorts of exotic things. You are faced with more than the "common pond life" that the simple-minded keys I referred you to are intended to help with.

You are also learning the fact about photographs -- some of yours are unusually good but they simply do not convey the detail of information that a trained eye can see, especially as the trained brain integrates the information from different views and images from different angles. That is why making drawings is so important. In a good drawing, you illustrate those features that are really important, showing them clearly. Of course the Haeckel episode reminds us that drawings are different from real life, but photographs are also different from real life. Making truly detailed and useful photomicrographs is a talent that requires special training and long practice, not to mention rather better microscopes than what you are using. In other words, there really isn't enough detail in the pictures you display to see exactly what many of the things may be. Your commentator on the artscape salt-water-microbes web site identifies things as well as can be expected.

I hate to have to tell you this, but you will have to accept that some things will not be identifiable. That will come with long experience studying with experts. The fact that one of your instructors/mentors, Terri, apparently can't identify it all should be a clue. That is why doing science is a constant learning experience. It really does take years of guided training to do some things and, even then, you still keep learning as long as you live.

So welcome to the world of real science! You are off to an excellent start. You have a long way to go but the entire trip is a fantastic adventure!
- R. Norman

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Identifying Algae

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Enlarge image
Image captured by digital camera. I had more success at capturing a clearer image, in fewer shots by _not_ using "Super Macro" feature on my camera.

Enlarge image
This image was produced by the microscope software.

The question is, which strain of algae am I looking at? Several in the guide my instructor gave me bear resemblance to those in the charts.
17. Spirogyra (comparing with Google images, Spirogyra appears to bear similarity, but I have my doubts this is the identification.)
18, 19. Mougeotia though long and divided into section like my sample, I have my doubts.
20. Zygnema *also shares many similarities with the sample I've captured, but I have my doubts this is the identification.
28. Microspora

Although Microspora appears to bear striking similarities as well.
Source: Class Chlorophyceae
29. Ulothrix, possibly...
30. Oedogonium, another possibility.

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