Whale Watching
& Swimming-

Swimming with Whales
About the Whales
The Boats

About the Whales

We are lucky to have more than 7 types of cetaceans (whales and dolphins) visit Vava'u from the mighty Blue Whale at the largest to the tiny Spinner Dolphins. Sperm whales, Bryde's whales, Minke whales, Killer whales, False Killer whales, Pilot Whales and Bottle-Nosed Dolphins also cruise our coastline but the Humpback whales make Vava'u their home for a while.

Humpback are genetically programmed to return to mate and calve to a particular area which gives Tonga, and in particular, Vava'u their own humpback family. They feed in Antarctica but return each year between July and November. They are famous for their amazing songs which are distinct to their individual families, Tongan whales singing different songs to whales from French Polynesia, Samoa, or Australia.

The humpback whale is a baleen whale and a rorqual whale that sings amazing songs. It performs complex and cooperative feeding techniques. The humpback has a bulky head with bumpy protuberances (tubercles), each with a bristle. Humpbacks are acrobats of the ocean, breaching and slapping the water. They live in pods and have 2 blowholes. The name humpback describes the motion it makes as it arches its back out of the water in preparation for a dive.

Humpback whales grow to be about 52 feet (16 m) long, weighing 30-50 tons (27-45 tonnes). The females are slightly larger than males, as with all baleen whales. The four-chambered heart of the average humpback whale weighs about 430 pounds (195 kg) - about as much as three average adult human beings.

Mother and Child Paul Sutherland www.sutherlandimages.com

Humpbacks come in 4 different color schemes, ranging from white to gray to black to mottled. There are distinctive patches of white on underside of the flukes (tail). These markings are unique to each individual whale, like a fingerprint. The humpback's skin is frequently scarred and may have patches covered with diatoms.

Humpback whales have 14-35 throat grooves, or rorquals, that run from the chin to the navel. These grooves allow their throat to expand during the huge intake of water during filter feeding. They have small, round bumps on the front of the head (called knobs or tubercles), edging the jaws. The bristles on their tubercles allow them to 'feel' what is happening in the water around them. Humpback calves are frequently seen playing around Mum's nose where she can 'feel' they are safe. Humpbacks have huge, mottled white flippers with rough edges that are up to one-third of its body length; these are the largest flippers of any whale, and the largest limb in the animal kingdom. The humpback's genus, Megaptera Novaeangliae, means "huge-wings of New England," referring to its flippers, and the fact they were first identified in New England. The flippers may have manybarnacles growing on them, although they shed them in warm waters. Remora, or sucker fish, are also frequently seen living on the whales undersides.

Humpback whales (like all baleen whales) are seasonal feeders and carnivores that filter feed tiny crustaceans (krill - mainly Euphausia superba, copepods, etc.), plankton, and small fish (including herring, mackerel, capelin, and sandeel) from the water. They are gulpers (not skimmers), filter feeders that alternatively swim then gulp a mouthful of plankton or fish. Concentrated masses of prey are preferable for this method of feeding, which they do not usually find in their warmer breeding grounds. An average-sized humpback whale will eat 4,400-5,500 pounds (2000-2500 kg) of plankton, krill and small, schooling fish each day during the feeding season in cold waters (about 120 days). They eat twice a day.

Humpbacks cooperate in hunting and have developed a method of rounding up highly concentrated masses of prey that is called bubble-net feeding. The hunting members of a pod form a circle 10-100 feet (3.1-31 m) across and about 50 feet (15 m) under the water. Then the humpbacks blow a wall of bubbles as they swim to the surface in a spiral path. The cylindrical wall of bubbles makes the trapped krill, plankton, and/or small fish move to the surface of the water in a giant, concentrated mass.

The humpbacks then eat a large, hearty meal. The humpback whale has about 330 pairs of dark gray baleen plates with coarse gray bristles hanging from the jaws. They are about 25 inches (0.6 m) long and 13.5 inches (34 cm) wide. The baleen create a filter so the whale can eject the water after gulping a mouthful of fish. Humpback whales can dive for up to 30 minutes, but usually last only up to 15 minutes.

Humpbacks can dive to a depth of 500-700 feet (150-210 m). The males sing as they dive and the length and strength of their song is thought to be a demonstration of their strength. Their songs cover over 10 octaves and the human ear can hear less than half of what they sing.

Humpbacks are very acrobatic, often breaching high out of the water and then slapping the water as they come back down. Sometimes they twirl around while breaching. Breaching may be purely for play or may be used to loosen skin parasites, barnacles, and remora, or have some social meaning.

Spyhopping is another humpback activity in which the whale pokes its head out of the water for up to 30 seconds to take a look around. Whales, like other marine mammals, have an adjustable optic nerve which means they can change the shape of their lens to refocus their eyes to see in or out of the water.

Humpbacks also stick their tail out of the water into the air, swing it around, and then slap it on the water's surface; this is called lobtailing. It makes a very loud sound. The meaning or purpose of lobtailing is unknown, but may be done as a warning to the rest of the pod. Humpbacks lobtail more when the seas are rough and stormy. Slapping a fin against the surface of the water is another unexplained humpback activity but often seems to be a form of play.

Humpbacks have a semi-conscious breathing reflex which means they have to remember to breathe. For this reason only half of their brain is ever asleeep, so they sleep with one eye open and one eye closed. This is often seen whilst we swim with them and they show no alarm when they awake to find us near. Autopsies have shown the cortex of a whales brain to be 7 times more complicated than a humans, so we can only begin to wonder what they are thinking.

It was thought that humpbacks lived for up to 100 years but recently a humpback was found dead with a spear tip imbedded in its flesh dating back more than 200 years. The scarring around the spear suggested it had been there for some time, which has led scientists to wonder just how long they do live.

Did You Know?...
The Humpback song is the most complex of all whale species.