EPA's Stressor Identification Process and CADDIS

Biological monitoring and assessment has become an essential tool for describing the condition of water bodies.  When an undesirable condition has been documented, a causal assessment can help direct management action toward the cause of the problem.  This webinar will introduce participants to U.S. EPA’s Stressor Identification and the Causal Analysis/Diagnosis Decision Information System (CADDIS). The step-by-step process for causal assessment process described on CADDIS includes developing a list of candidate causes of the observed effects, deriving evidence for or against each alternative, and identifying the best explanation by considering all of the evidence.  We will describe the process and the derivation and evaluation of commonly encountered types of evidence.  We will also provide a tour of information and tools available on CADDIS and discuss recent experiences from case studies conducted in California. 

Presented by Scot E. Hagerthey and Susan B. Norton

Scot Hagerthey

Scot Hagerthey is an Ecologist in the U.S. EPA’s National Center for Environmental Assessment. His particular interests are assessing ecological condition, establishing causal relationships, developing predictive tools, assessing restoration outcomes, and quantifying ecological risk. His career has focused primarily on algae as biological indicators of aquatic ecosystem condition. Dr. Hagerthey received his BS in Biology from East Carolina University and his PhD in Biology from Michigan Technological University.

Susan Norton

Susan Norton is a Senior Ecologist in the U.S. EPA’s National Center for Environmental Assessment. Since joining EPA in 1988, she has developed methods and guidance to better use ecological knowledge to inform environmental decisions.  She has published numerous articles on ecological assessment and edited the book Ecological Assessment of Aquatic Resources: Linking Science to Decision-Making.  Dr. Norton received her BS in Plant Science from Penn State, her MS in Natural Resources from Cornell University, and her PhD in Environmental Biology from George Mason University.