North Atlantic minke whales (Balaenoptera acutorostrata acutorostrata) were acoustically detected and localized in real-time for 3.5 h off Jacksonville, Florida. During 1 h of this encounter, an individual was visually and acoustically tracked. Manual review of the recordings identified continuous low-frequency pulse trains (40–674 Hz). Not all pulse trains observed have been documented previously in the North Atlantic. Variation in frequency, duration, and the combination of known pulse trains were documented. The tracked whale also altered its calling behavior while the research vessel was present. These data provide insight into the acoustic behavior of minke whales in their winter habitat.