Effective and appropriate use of science requires decision makers to acknowledge inherent scientific uncertainties, even as stakeholders may be frustrated if scientists are not willing or able to make clear and precise forecasts of river responses to a given management proposal. Use of “if-then” questions—if management action “x” is taken, then consequences “y” and “z” are likely to result—may help frame and focus scientific questions and direct scientists to explain areas of scientific consensus and the bases for that consensus. This “if-then” question format also means that when uncertainties lead to scientific disagreement, scientists are still responsible for identifying uncertainties and describing their causes. There are instances in which decisions can and must be made in the face of scientific uncertainty. In these cases, scientists may frame predictions in terms of likely outcomes, probabilities, or a range of future scenarios, offering evaluations on the likelihood of different outcomes given the state of knowledge. Where uncertainties abound but decisions need to be made, adaptive management suggests basing decisions on a learning-by-doing approach.
Defining and adhering to boundaries between science and policy is a complicated and challenging process for decision makers, stakeholder groups, and scientists. Effective use of scientific information in Missouri River decision making will require these parties to acknowledge the different domains of science and policy, seek their respective boundaries, and appreciate the limits of knowledge about the river’s natural systems.