Temporal Persistence as Condition-Dependent Signaling in Baleen Whale Breeding Acoustics

Breeding-ground vocalizations in large baleen whales are characterized by long-duration, low-frequency, hierarchically structured songs produced predominantly by males. Females produce shorter social calls and frequently approach singing males without engaging in equivalent large-scale broadcast behaviour. Across humpback, blue, and fin whales, mating contexts exhibit sustained unilateral acoustic persistence, low-frequency dominance, and extended temporal duration with minimal large-scale alternation. In contrast, odontocetes such as killer whales and bottlenose dolphins display bilateral vocal exchange, shorter-duration signals, higher dominant frequencies, and rapid update dynamics during mating interactions. This comparative pattern suggests a body-scale dependent shift in dominant temporal operating mode. In large baleen whales, breeding vocalizations operate within a persistence-dominated regime in which temporal endurance under acoustic overlap functions as a condition-dependent display. Rather than structured acoustic contest or dialogic exchange, breeding song reflects sustained oscillator stability under interference. Disturbance contexts reveal rapid temporal compression and reduced complexity, demonstrating regime-specific architecture within the same species. This framework emphasizes temporal persistence and acoustic stability under load as central structural variables in baleen whale breeding acoustics.