Effective aquatic invasive species (AIS) management requires resource-users engage in mitigation behaviors that prevent unintentional AIS spread. As such, it is necessary to examine the behaviors users currently engage in, why they chose to do so or not, and how might natural resource managers influence users to engage is necessary behaviors. Informed by theories from social and environmental psychology, this dissertation examines normative social aspects of Texas boaters' AIS mitigation behaviors, i.e., perceived and actual social norms. Chapter II draws on the return potential framework to understand the relationship between boaters injunctive beliefs (beliefs concerning what should be done) and descriptive beliefs (beliefs concerning what is be done). Chapter III employs a quasi-experimental design to examine how different message frames affect boaters' intentions to engage in AIS mitigation behaviors. Chapter IV examines the belief-behavior process by asking how descriptive and injunctive beliefs and aspects of social comparison influence behavior. Collectively, findings from the three studies have implications for practice and theory. For theory, findings have direct implications for the plausibility of theoretical tenets related to normative social influence and the conditions under which normative social beliefs do or do not affect behavior. For practice, findings highlight influential variables that influence a boater's decision to engage in AIS mitigation, providing practitioners with insights to influence or facilitate behaviors that result in desired outcomes.
