The humpback whale is a species of baleen whale. One of the larger rorqual species, adults range in length from 12–16 m and weigh around 25–30 metric tons. The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. It is known for breaching and other distinctive surface behaviors, making it popular with whale watchers. Males produce a complex song lasting 10 to 20 minutes, which they repeat for hours at a time.