Upper Klamath Lake Case Study

A brilliant young ecologist, Dan McGarvey, approached me about a problem with fish monitoring on Upper Klamath Lake. The National Research Council had released an interim report on the effects of lake levels on the concentration of algae in the reservoir (excess algae could be bad for two endangered fish species). They reported that based on their findings there was only a 32% chance that changes in lake elevation caused changes in algae concentrations.

This was misinterpreted as indicating that their was a 68% chance that changes in lake elevation did not cause a change in algae. Although these findings might appear to be congruent they are not. When we conducted the statistical power analysis, we found that the study they designed was only 2% likely to detect a relevant change in algae concentration.

In this case, the study did not provide evidence of anything--and because of that, the lack of a change was meaningless. Even the National Research Council can make mistakes--some more embarrassing than others. River Continuum Concepts can help you avoid these situations by planing a better study and ensuring the limitations of the study are known in advance.