The longest and most complicated mating song in the natural world is sung by the male humpback whale (Megaptera novaeangliae). The song is made up of themes and phrases and lasts from 6 to 35 minutes. No sooner has it finished than the whale starts again from the beginning. This can be heard through the water several hundred miles away. Interestingly, different whale populations in different oceans sing different songs.
In the northern hemisphere, the humpback whale spends the summer in its feeding grounds in rich polar seas, heading south in the autumn to spend the breeding season (January to March) in more tropical waters. Sometimes a group might be trapped beneath moving ice packs as winter sets in. If they cannot escape to the open sea, they will eventually die.