Pacific salmon are culturally, ecologically, and economically important throughout their geographic range. They are also increasingly depleted and threatened with extinction. This interrupted case study in three parts focuses on issues surrounding migration of this keystone species and how its ecology appears to be impacted by climate change. The storyline follows a young Alaskan who takes a summer job working at a Pacific salmon weir (a fish counting facility) and learns about observed shifts in the migration timing of several species of Pacific salmon, trout, and char (all in the Salmonid family). A selection of recommended videos provides context (approximately 15 minutes total viewing time), and the questions at the end of each section can be addressed with different levels of sophistication depending on the background of students. Simple calculations provide students an opportunity to think about the effects of climate change on the development, physiology, ecological interactions and evolution of Pacific salmon. Students also consider experimental design and influences of human harvest on natural populations. The case is suitable for students in an AP high school or lower-level college general biology, ecology, or environmental science course.