Humpback facts

Length: 11.5m15m (adult) 4m5m (juvenile), Weight: 2530 tonnes.

Description: Humpbacks have a small dorsal fin with a distinctive hump at its front, knobbly protuberances on their head, tip of lower jaw and leading edge of their extremely long flippers.

Activity: Travel mainly along the South Island’s east coast and through Cook Strait during winter, returning along the west coast in spring. Migrate between highlatitude summer feeding grounds and lowlatitude winter breeding and calving grounds.

Diet: Baleen feeders with a diet including krill and small fish like mackerel and herring. According to Doc they ‘‘show the most diverse feeding techniques of all baleen whales, including lunging through patches of prey, stunning prey with their flippers and forming ‘bubblenets’.’’

Rules: Maintain a distance of 50m at all times from whales. Approach whales from the side and slightly to the rear. Stay in your boat — swimming with wales is not permitted.

Famous for: Their spectacular breaching and beautiful, complex songs.

Conservation status: ‘‘Least concern’’.

Worldwide population: At least 80,000.