~ How
to collect Microscopic Pond Life ~
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The easiest way to collect micro-organisms and other small pond life is to squeeze the water from water plants or pond scum into a container. Another method is to scrape the growth from water plants or other things that are covered by a green or brown growth. An old credit card will make an excellent scraper but be careful not to drop it in the pond! A plankton net is recommended for free swimming (planktonic) species. This is a net made of a very fine meshed cloth with a small container at the end. You can also use the plankton net to concentrate the material squeezed out of water plants. |
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Desmids: These beautiful small algae are most abundant in waters without too many nutrients or acid waters. Bogs are often good collecting spots. Squeezing Sphagnum moss is a good method. Desmids often attach themselves to these plants. | ||
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Amoeba: These remarkable protozoa often live feeding on organic material on the bottom sediment of a pond. A good method of collecting them is to lower a jar upside down until it is positioned just above the mud surface. Then slowly let the air escape so the top layer will be sucked into the jar. You can move the jar slowly when tilting so you collect from a larger area. | |
Hydra: (see first page for links) They can be collected by putting duckweed or other waterweed into a glass jar full of water. Then wait for some hours. The hydras can then be found attached to the glass. | ||
Examining the growth scraped off surfaces with a hand lens can give a clue to the creatures present. If the growth is brown there is a good chance you will find diatoms. White fluffy masses are often colonies of bell animalcules. | ||
Keeping and culturing Algae or Protozoa. It is recommended to keep pond organisms
in a shallow container. A large surface with only a couple of centimeters of water will ensure there is enough
oxygen in the water. For culturing algae a simple method is to cook some garden soil in water. After cooling you can incubate it with the algae you want to grow. For bacteria eating protozoa like paramecium you can boil dry grass in water. Wait for one or two weeks until a layer of bacteria grows under the surface. Then incubate it with a bit of pond water containing ciliates. |
Other Micscape resources on collecting micro organisms:
Above text by Wim van Egmond.
Comments to the compilers Wim
van Egmond and Dave Walker are welcomed.
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