How do Bacteria and Fungi affect Emigration Creek and the organisms that live there?
For being such small organisms, bacteria and fungi do a lot to contribute to the health of the creek, both positively and negatively. Major effects of their presence are chemical processes like nitrogen fixation, ammonification, and nitrification that these tiny microbes perform, processes by which organic forms of nitrogen in dead organic matter is converted to chemical compounds that algae and plant roots can reabsorb.  Bacteria and fungi are also the beginning of the food chain for many of the organisms in the creek, which can be studied in more detail by clicking below. Finally, some fungi and bacteria are bad for the plants and animals they are neighbors with. Whirling Disease, caused by a harmful fungi, affects many fish including trout, but is it not yet known whether it affect the trout that live in Emigration Creek.

Nitrogen Fixation

In many cells, nitrogen is used as a building block to help create proteins and nucleic acids. Yet it is not usable in its atmospheric form (nitrogen gas), and must be converted to an inorganic compound such as nitrate or ammonia in order to be absorbed by plants and algae to be used. 


Animals excrete nitrogen as urea and ammonia through their waste, and it is also found in dead organic matter. Bacteria and fungi are useful here, because they can convert organic nitrogen to ammonia that is useful to plants through a process called ammonification. 


Certain bacteria also convert ammonia to nitrate through nitrification, making the element available for other organisms but also providing energy to the bacteria. 

Nitrogen is what is called a limiting nutrient to most ecosystems, because it is necessary to keep ecosystems productive yet it is a relatively slow process to get nitrogen back into the cycle as usable energy. Now do you see why having a lot of bacteria and fungi around is so important?

Food Chain

Do you realize how many organisms depend on bacteria and fungi? More that you would think! Here are some of the other organisms in Emigration Creek that depend on having these microbes around.

Cladophora and diatoms are kinds of algae that work together with bacteria and fungi to form biofilm, described earlier.  This community of photosynthetic algae and bacteria and fungi is grazed on by snails, caddisflies and mayflies, and other tiny invertebrate organisms!

Do you know why Emigration Creek is not totally clogged with leaves? Bacteria and fungi are able to break them down and keep the creek clear!

Do you know how many species of worms Emigration Creek has? We have planaria, leeches, and oligochetes, and all of these depend on bacteria and fungi in one way or another. Worms break down organisms too- can you seen what a connected ecosystem this is? Every part of the creek is dependent on another part!

Whirling Disease

Whirling Disease is an infection striking fish that causes symptoms of blackening of the tail, head and spine deformity, and a whirling behavior when the fish is swimming or startled, hence the name. The fish in Emigration Creek, Rainbow Trout, are susceptible to this disease, and it is caused by a tiny parasite called Myxobolus cerebralis, which is spread by spores of a particularly nasty form of fungus. Bigger fish can carry the disease and not show any symptoms, but if the spores are passed to smaller, younger fish, they are more susceptible and die quickly. This targeting of young populations of fish is why the disease is so devastating, and many states are trying many different ways to combat the disease. The spores are very resilient, and can be passed from one water source to another through introduction of new fish and fish eating birds. They can survive in mud that sticks to the bottom of your shoe or boat, and Russian scientists even found that spores can remain viable for up to 30 years in dried mud! We don't know yet if Emigration Creek trout are infected with Whirling Disease, but the disease has recently been found on the Weber River and Provo River.

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