Dolphin Interferon-Alpha (IFN-α) is a type I interferon produced by virus-infected cells and plasmacytoid dendritic cell–like populations in dolphins, particularly the bottlenose dolphin (Tursiops truncatus), where it plays a central role in innate antiviral immunity. Upon binding to the type I interferon receptor complex (IFNAR1/IFNAR2), dolphin IFN-α activates JAK/STAT signaling pathways, leading to induction of interferon-stimulated genes (ISGs) that inhibit viral replication, enhance antigen presentation, and promote activation of natural killer (NK) cells and adaptive immune responses. IFN-α is upregulated in response to viral infections documented in dolphins, including cetacean morbillivirus, herpesvirus, papillomavirus, and other emerging marine pathogens, and serves as an important biomarker of antiviral immune activation. Dysregulation of type I interferon responses may contribute to immunopathology or altered susceptibility under environmental stress conditions such as pollutant exposure or harmful algal blooms. In marine mammal health research, characterization of dolphin IFN-α supports studies of host–virus interactions, immune adaptation to aquatic environments, and conservation medicine. Additionally, dolphins serve as sentinel species for ocean ecosystem health, and investigation of IFN-α responses provides comparative insight into antiviral immunity, environmental immunotoxicology, and type I interferon biology relevant to both wildlife conservation and human infectious disease research.