Sea Wonder: Humpback Whale

The scientific name of the humpback whale, Megaptera novaeangliae, translates roughly to “large-winged,” a reference to the species’ enormous pectoral fins, which can grow to around one-third of the whale’s total body length. Their common name comes from the noticeable hump located just ahead of the dorsal fin. Because of their impressive size and energetic behavior, humpback whales are among the favorite species of whale watchers.

Description

Adult humpback whales can grow to approximately 43 to 52 feet in length and may weigh as much as 80,000 pounds. Females are typically larger than males. Their bodies are predominantly black, although varying amounts of white can appear on the pectoral fins, underside, and tail flukes.

The amount and distribution of white coloration differs from one whale to another. These variations are influenced by individual genetics as well as the geographic location of the population. A humpback whale’s tail flukes can measure up to 18 feet across, while its long pectoral fins may approach a similar length.

Every humpback has a unique pattern on its tail flukes, much like the individuality of human fingerprints. Researchers can therefore use these markings to recognize and identify particular whales.

Inside the whale’s mouth are baleen plates made from keratin, the same basic material found in human hair and fingernails. These plates allow humpbacks to filter food from seawater. They have one eye on either side of the head, two blowholes on top of the skull for breathing, and a relatively small dorsal fin located about halfway along the back. A noticeable hump sits immediately in front of this fin.

Diet and Habitat

Humpback whales are divided into three major populations that occupy separate ocean regions and generally do not interact with one another. These populations occur in the North Pacific, North Atlantic, and Southern Hemisphere. Within these broad regions are additional subpopulations, some of which may interact while others remain separate.

Humpback whales are absent from only a few major marine areas, most notably the Arctic waters surrounding the North Pole and the Mediterranean Sea between Africa and Europe.

These whales are migratory animals that generally inhabit relatively shallow ocean waters. Their location changes with the seasons. During the breeding and calving period, they favor warmer tropical and subtropical waters. When summer arrives, they move toward cooler temperate regions where food is more abundant.

Humpback whales can be observed throughout the National Marine Sanctuary System. Important areas include Channel Islands National Marine Sanctuary and Monterey Bay National Marine Sanctuary along the West Coast. They are also found at Stellwagen Bank National Marine Sanctuary during summer and at Hawaiian Islands Humpback Whale National Marine Sanctuary during winter.

Despite being among the largest animals on Earth, humpback whales depend heavily on much smaller creatures for food. Their diets commonly include tiny crustaceans such as krill as well as small fish. Because they filter enormous quantities of seawater through their baleen, they have limited control over every individual organism that enters their mouths.

Humpback whales are capable of feeding cooperatively, although their hunting methods can vary according to their location. One common technique is lunge feeding, in which a whale rapidly moves through a school of fish with its mouth open. Another remarkable strategy is bubble-net feeding. Several whales can work together to surround a school of fish and release bubbles around it, forming a kind of underwater barrier. The whales then swim upward through the concentrated prey with their mouths open.

During summer, an adult humpback whale may consume as much as 3,000 pounds of food in a single day. This heavy feeding period allows the whales to build substantial fat reserves, which provide energy during their long migrations and the periods of limited food availability in their winter calving grounds.

Life History

Humpback calves are usually born in tropical or subtropical waters during the winter following a pregnancy that lasts approximately one year. Newborn calves depend on their mothers for milk and gradually begin learning how to capture and consume solid food as they travel toward their summer feeding areas.

A mother may continue nursing her calf for more than a year before weaning it. Even after weaning, young humpbacks continue developing and growing for roughly another decade. These whales can potentially live for more than 80 years, although their average lifespan appears to be closer to 50 years.

During migration, humpback whales commonly travel in relatively small groups that may consist of a mother, her calf, and occasionally an accompanying male known as an escort. Outside migration periods, however, they may gather in much larger groups for cooperative feeding or mating activities.

Despite their enormous size, humpback whales are highly athletic animals. Their spectacular behaviors make them especially popular with whale watchers. They may breach completely or partially out of the water, slap their fins against the surface, perform spy hops, and display many other dramatic movements.

The Songs of Humpback Whales

Humpback whales are especially famous for their complex vocalizations, which are commonly described as “songs.” These sounds became widely known after bio-acoustician Dr. Roger Payne released the album Songs of the Humpback Whale in 1970.

Their vocal repertoire includes moans, cries, howls, and numerous other sounds. Males are generally the individuals known for producing the elaborate songs.

A single song can continue for as long as 20 minutes. Scientists still do not completely understand why humpback whales sing, although the sounds may play a role in helping males locate potential mates in the vast open ocean.

Unlike land mammals, whales and dolphins do not produce their vocalizations directly through their mouths. Instead, they push air through specialized muscles near their blowholes and manipulate these structures to generate different sounds.

Threats and Conservation

Historical commercial whaling had a devastating impact on humpback whales, causing nearly every major population to decline dramatically. Changes in international policies, along with the 1985 moratorium on commercial whaling, helped humpbacks and other large whale species begin recovering.

Despite this progress, several humpback populations are still classified as threatened, endangered, or depleted. In the United States, humpback whales are protected under the Marine Mammal Protection Act, while certain populations also receive protection under the Endangered Species Act.

Today, humpback whales continue to face numerous human-related and environmental challenges. These include collisions with ships, climate-related changes affecting prey and habitat, underwater noise created by human activities, habitat degradation, and entanglement in fishing equipment and marine debris.

Entanglement has become an especially important concern for humpback whales. Fishing ropes, nets, and other marine debris can become caught around a whale or attached to its body while it is swimming. Such incidents can severely limit movement and may cause serious injuries or death.

According to NOAA’s 2024 national report concerning large-whale entanglements, confirmed cases increased in 2024 and were significantly higher than the historical average. Humpback whales remained the species most frequently involved, accounting for 77 reported cases. Approximately one-quarter of all documented entanglements occurred along the California coast, with a large portion concentrated around Monterey Bay.

The Foundation’s Conservation Efforts

The National Marine Sanctuary Foundation collaborates with numerous organizations, fishermen, and other stakeholders to help prevent and reduce whale entanglements in California.

One part of this work involves cooperating with commercial fishermen to test and develop innovative fishing equipment. Another involves supporting training programs for responders who work to free whales that have become trapped in fishing gear.

A particularly important area of research involves pop-up, also known as on-demand, fishing systems. These technologies are designed to eliminate the need for vertical buoy lines extending through the water column. Removing those lines can substantially reduce the likelihood of whales becoming entangled while still allowing fishermen to continue their work during periods when traditional fishing equipment presents a greater risk.

As of June 30, 2025, participating fishermen had completed 880 trials involving six different on-demand fishing systems. These tests have generated valuable information and practical insights that can be used to improve equipment designs and develop solutions that protect whales while also supporting sustainable fishing livelihoods.

Responding to Entangled Whales

When a humpback whale becomes entangled off the California coast, the West Coast Whale Entanglement Response Network can respond. Without human intervention, an entangled whale may remain trapped for months or even years, potentially suffering prolonged injury and exhaustion.

The National Marine Sanctuary Foundation supports this response effort by helping train specialized whale-rescue personnel. These responders work directly on the water and use carefully planned techniques to safely approach and release whales from dangerous entanglements.

Through improved fishing technology, scientific research, responder training, and cooperation with the fishing community, conservation organizations continue working toward reducing the risks humpback whales face while supporting healthy marine ecosystems and sustainable human activities.