Marine Mammals

Humpback Whale

Megaptera novaeangliae

Also known as

The translation of their scientific name is large-winged From New England

Distribution

Tropical, temperate and sub-Arctic waters worldwide

Ecosystem/Habitat

High latitude summer feeding grounds; low latitude winter breeding grounds

Feeding Habits

Filter-feeder

Taxonomy

Suborder Mysticeti (baleen whales); Family Balaenopteridae (rorqual whales)

Humpback whales are renowned for their charismatic, awe-inspiring behaviours above and below the ocean’s surface. Humpbacks frequently launch themselves into the air and land with a splash, known as breaching. They also slap the surface of the water with their long, jagged pectoral fins, the largest relative to body size of any whale. Their equally huge flukes are uniquely marked with mottled patterns like fingerprints, which scientists use to identify individuals using photo-identification catalogues. Humpbacks can also be tracked acoustically, as they sing the most complex songs of any marine mammal and can be heard from hundreds of kilometers away. These songs are often repeated for hours by males to attract females, and can change over time as whales learn new dialogues from each other. Their incredible social behaviours don’t stop there: humpback pods will feed together by encircling a school of small fish with bubbles, condensing them in a so-called ‘bubble net’ for easy capture with a single lunge.

Humpback whales have white undersides and a small dorsal fin centered on their black backs. Their throats have deep skin folds, known as rorqual grooves, which expand during feeding to engulf large volumes of water. The water is then pushed through their baleen plates to trap krill and small fish. Humpbacks are covered in round bumps called tubercles on their head, neck and fins. Their long pectoral fins give them their genus name “Megaptera,” meaning “large-winged” and their flukes are broad. They have an overall body size of 13-14 metres long and weigh up to 45 tonnes.

Humpback whales reach sexual maturity at age nine and are considered fully-grown by the age of 12 to18. Every one to five years, females give birth to calves that weight one tonne and are more than four metres long. Winter calving occurs between January and April at southern breeding grounds that are sheltered from predators, during which time mothers do not feed. Instead, the whales must rely on fat reserves developed during the summer at productive, high latitude feeding grounds. Calves are nursed for 10 to11 months, but can remain with their mothers after weaning for more than a year. Afterward, humpback whales will associate in loose, fluid groups that last only a few days at a time. They forage cooperatively for krill, zooplankton and small fish by bubble-netting and lunge-feeding.

Humpback whales are slow swimmers and spend much of their time near the surface: this previously made them an easy target for overexploitation by commercial whaling. While their populations have rebounded dramatically, they are still well below their pre-whaling estimates. This is because of modern threats to their survival, including heavy harvest of their prey by commercial fisheries, particularly small fish like capelin, herring, or sand lance. Reduced prey availability impedes their prolonged growth and survival.

Another serious threat to humpback whales is interactions with fishing vessels. Humpback whales are the most commonly reported species involved in vessel strikes as shipping and fishing activities often overlap with key breeding and feeding areas. Shipping can exclude whales from important habitat, and underwater noise from engines, propellers and other moving parts on a ship can mask their vocal communications.

Humpback whales are also at risk of entanglement in fishing gear, which can interfere with their normal movement and feeding, potentially suffocating or starving them. The catch of non-target fish and ocean wildlife, or “bycatch,” results in unnecessary waste and harm to many marine species, including humpback whales. Oceana Canada is working to reduce bycatch and better protect species at risk. Find out more about how you can help at Oceana.ca/Bycatch.

There are approximately 4,000 humpback whales in the Northwest Atlantic population and more than 18,000 in North Pacific population. The global population is increasing at an estimated rate of 4.9-6.8 per cent annually. However, these numbers are still small compared to their estimated abundance before whaling.

Below are the conservation statuses of each population based on assessments by The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and listing under the Species at Risk Act (SARA):

North Pacific population. COSEWIC listing: Special Concern – 2011, SARA listing: Schedule 1, Special Concern
Western North Atlantic population. COSEWIC listing: Not at Risk – 2003, SARA listing: Not at Risk

Fisheries and Oceans Canada - species profile

Oceana

Species at Risk Public Registry - species profile