Page 20 - The Freshwater Mussels of Oklahoma

lose species that are high in the food chain. This, in turn, has a trickle down effect that
ultimately results in a system with a drastically diminished diversity. Consequently, low
diversity means less stability and increases the likelihood of extinction within the system.
Freshwater aquatic systems function much like islands or fragmented ecosystems. Lakes
tend to be isolated from other lakes. Rivers, especially second and third order tributaries,
function as ”islands” by being cut off from one another by mainstem rivers and the
surrounding terrestrial ecosystems. Second and third order tributaries tend to contain
endemic species that have evolved in these streams and are adapted to the specific water
chemistry, flow regimes, substrates and fish hosts. These populations are particularly
susceptible to any or all of the previously discussed factors.

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