The songs of the male humpback whales (Megaptera novaeangliae) have traditionally

been associated with mating at tropical and subtropical mating grounds during winter.

However, songs also occur out of mating season, both on feeding grounds in spring,

late summer and fall. This study provides the first report of humpback whale singing

behaviour in the subarctic waters off Northeast Iceland (Skjálfandi Bay) using long term

bottom-moored acoustic recorders during September 2008-February 2009 and from

April-September 2009. Singing started in late November and peaked in February,

within the breeding season. No songs were detected from spring to fall, despite of

visual detections of humpback whales. Non-song sound signals from humpback

whales were detected during all recording months. Songs were partly composed of

fundamental units common with other known mating grounds, and partly of song units

likely unique to the study area. The variety of song unit types in the songs increased at

the end of the winter recordings, indicating a gradual change in the songs throughout

the winter season; as has been shown on traditional mating grounds. The relative

proportion of songs compared to non-song signals was higher during dark hours than

daylight hours. The short light periods of the winter, and where food is available, likely

influence the daily occurrence of humpback whales' songs in the subarctic.