Informal higher education science learning programs are increasingly being used as a tool to build scientific research capacity. However, there is low understanding of the impact that these programs on their target audiences, which is important to future capacity building efforts and program design. The purpose of this research project is to address this gap in understanding by exploring the scope of impacts that an international informal higher education science learning program was perceived to have on its student learners and scientist-instructors. Twelve marine professionals, 103 learners, and 19 instructors participated in this mixed-methods case study. Data collection included 185 surveys, 22 interviews, a task-based focus group with 13 participants, and participant observation. Interviews with the professionals were used to provide contextual understanding for the research. Findings indicated that, in the short-term, learners experienced positive changes in their research skills, content knowledge, and conceptual knowledge. Learners did not perceive a change in their attitudes toward marine science or beliefs about science careers. Instructors perceived a positive impact from both cultural-exchange and the opportunity to advance their field. Overall, the instructors did not perceive any significant professional or career development impacts. These findings suggest that scientific research capacity at the individual level can be fostered by scientist-driven outreach programs, and recommends that future programming focus on creating space for different types of connections and increasing the value of scientist-instructor participation. A program evaluation summary for the informal higher education science learning program was also completed, with a synthesis of learner and instructor feedback and recommendations for future development.