Humpback Whale Safety
Humpback Whale season in Hawaii runs from November through May, with the peak occurring January through March. As many as 12,000 Humpback Whales winter in Hawaiian waters each year, and the Hawaiian Islands Humpback Whale National Marine Sanctuary wants to remind us to stay safe. These acrobatic, 45-ton marine mammals attract wildlife enthusiasts, but collisions between vessels and whales pose a serious threat of injury to both the animals and boaters.
Although the population of Humpback Whales (Megaptera novaeangliae) is increasing, they remain endangered, and the sanctuary was designated to protect them and their habitat in Hawaii. Ocean stewardship is deeply embedded in the Native Hawaiian culture, and the santuary works to enhance awareness of Native Hawaiian values for the protection of the whale (kohola) and Hawaii’s marine environment.
Federal regulations prohibit approaching within 100 yards of whales when in the water, and 1,000 feet when operating an aircraft. These and other federal marine mammal and endangered species protection regulations apply to all ocean users, including vessel operators, kayakers, and paddle boarders, throughout the Hawaiian Islands. “Collisions with vessels are a major source of injury and death for endangered whales in Hawaii,” said NOAA’s Office. “It’s important for boaters to be extra vigilant during whale season, for their own safety and the protection of these magnificent animals.” Photo by Ed Lyman.
Humpback Whale Song Structure
The Humpback Whale Song is an amazing acoustic display. Scientists first recognized these songs as coming from humpback whales in the 1960s, and have been studying the general structure of the song as well as the characteristics of singers. Only male Humpback Whales (Megaptera novaeangliae) sing, and usually during the breeding season.
The song has a predictable structure with a series of sounds, repeated over time in phrases, with each phrase repeated several times to comprise a theme. A typical song is made up of half a dozen themes that are usually repeated in a sequential order. A song typically lasts 5 to 20 minutes, and then is repeated over and over in a session that may last several hours. The sounds that comprise a humpback song are varied and can range from high-pitched squeaks to lower frequency roars and ratchets.
A striking feature of the song is that it gradually changes or evolves over time. Each year, different sounds and arrangements of sounds form to create new phrases or themes. These changes are slowly incorporated into the song, while some older patterns are lost completely. The change in the song seems to occur in a collective or common way throughout the population, and after a period of several years, the song is virtually unrecognizable from the original version.
Despite the constantly changing nature of the song, all singers in a population sing essentially the same version at any one time. As an example, all the singers encompassed in the millions of square miles of the North Pacific sing essentially the same version of a song at any one time. But, Humpback Whales in the South Pacific Ocean will have a different song than those in the North Pacific.
Humpback Whale Calves
Humpback whales become reproductively mature when they are between five and eight years of age. They mate during their winter migration to Hawaii, and eleven to twelve months later, upon their return to winter breeding grounds, the mother gives birth to a single calf. A fifty foot mother will give birth to a calf approximately fifteen feet long and weighing around two tons. The newborn instinctively swims to the surface within 10 seconds for its first breath. The mother begins feeding her newborn about 100 pounds of milk each day for a period of around six months, then the calf is sustained through a mixture of nursing and independent feeding for six months more. The mother’s milk is pink in color and exceptionally high in fat content (50%) which allows the calves to gain weight quickly. It is imperative for them to develop a thick layer of blubber prior to their 3,000-mile migration back to the cold Alaskan waters. After weaning, the calf has doubled its length and has increased its weight five times, attaining a size of about thirty feet and ten tons.
In Hawaii, humpback whales typically belong to groups consisting of two to three individuals for relatively short periods of time. The longest association between individual whales is when the mother cow, remains with her calf for a year during nursing. The mother generally never lets her calf stray more than a body length away for very long. They spend the first year or so of the calf’s life together, and the calf learns valuable survival lessons in this short amount of time, and is then weaned and separated. In many instances, cow and calf are accompanied by another adult known as an escort. Escorts can be of either sex, but are most often reported to be males, and remain with them for only a short time. Usually, a female humpback will bear one calf every two or three years, with an average life span between 40 and 50 years.
Humpback Whale Wing on Wing
The humpback whale’s scientific name is Megaptera novaeangliae, meaning ‘Giant Wings of New England’, which refers to their large pectoral fins that can reach a length of 15 feet. These fins are used for maneuverability, stabilization, enabling the whale to stop, and swim backwards. And sometimes they are used just to show off.
Photo by Phillip Colla
Humpback Whale Tail Slap
The most powerful part of the whale’s anatomy is it’s tail. By smacking it forcefully on the surface of the water, Humpbacks produce loud clapping sounds with big splash displays. Humpback whales will float vertically in the water, with their head pointing downward, meanwhile raising their tail out of the water and slapping their flukes against the surface. It’s common to see humpbacks slapping their tails several times in a row, which can be heard for great distances by other whales.
Humpback Whale Spy Hop
In performing a spy hop the humpback whale rises vertically with its head out of the water. It is a controlled maneuver that can last for minutes at a time if the whale is sufficiently inquisitive about whatever (or whomever) it is viewing. To maintain this elevated position they rely on their exceptional buoyancy control and positioning with pectoral fins. They may then slowly turn to look around, and drop back down in the water.
