Humpback Whales: The Great Navigator in the Ocean

 by Senzo Uchida

Humpback Whale

Humpback Whale

Humpback whales navigate a long distance of ocean in their migrations. In the summer months they feed the abundant food in the seas of the higher latitudes and in the winter descend on the warm waters of the lower latitudes to breed.

In summer in the North Pacific they fatten themselves in the rich seas of the Aleutians and Alaska. In the autumn some of them start traveling southward in the northwestern Pacific to Okinawa and Ogasawara, where they stay through the winter and spring.

Wintering in the warm waters, they come to breed and mate, and in late spring begin their journey to their feeding grounds in the north. Nursing their young calves, mother humpbacks swim northward as well.

The habit of staying close to the shore in both their breeding and feeding areas has been a cause of misfortune for the slow swimming humpbacks. These habits made it easy for them to be captured by small whaling boats using only simple hand thrown harpoons during former times when they were hunted. When the fleets modernized to harpoon guns, these whales were hunted indiscriminately to the brink of extinction.

The humpbacks that had traditionally migrated to Okinawa sharply decreased in population around the 1960's due to whaling in the Ryukyus and the northern seas. Finally in 1966 the total ban on whaling was instituted.

By the 1980's, about fifteen years after the whaling ban, the first signs of recovery for the population of humpbacks in the Okinawa waters could be seen. By 1990 there were enough whales to establish a number of whale watching tourist businesses that operate January through March in the seas off Okinawa.

In 1990 the Okinawa Expo Aquarium started the field research on whales with the grant of the Tokai Foundation on the population levels of humpback whales. This is the first long-term study on whales conducted in Japan.

Individual humpbacks can be identified by the patterns on their tail flukes. In the nine years since the beginning of the study 280 individuals have been identified.

The results of the survey since 1975 by the Okinawa Expo Aquarium showed twenty-six species of whales and dolphins distributed in the seas around Okinawa. Aside from the humpback whales, higher appearance rates of the southern species of whales and dolphins such as the Blainville's Beaked Whale, Melonhead Whale, Pigmy Killer Whale, and Roughtoothed Dolphin show the distinctive features of cetacean fauna.

There are excellent chances for humpback whale-watchers by chance to encounter Roughtoothed Dolphins, False Killer Whales, Risso's Dolphins, and Bridled Porpoises. A little farther off shore you can expect to see Sperm Whales as well.

Humpback whale-watching is currently centered on the Kerama Island group but should the migratory populations continue to increase there is the possibility of seeing the businesses expand to the tourist centers on the main island of Okinawa, the dream of many on the islands.
 

Dr. Senzo Uchida has been the director of the Okinawa Expo Aquarium since 1981. His study includes regional researches of humpback whales in the Aleutians in 1992 and 1995, and in Alaska in 1994 and 1995.

See also

About ten years ago,island fishermen reported seeing whales in the area. Then the humpback whales have returned to the Kerama,where they once were hunted. Foer several years the number of whales migrating to the Kerama gradually increased. Current from February to March every year,many boats (departed from Naha and each islands) is used for whale watching around the Kerama islands.
 Study of Humpback Whales in Japanese Waters WWF Japan supported a survey of humpback whales in Japanese waters from 1988 to 1995. The survey was initiated by a Canadian scientist, Dr.James Darling, with help of Japanese volunteers. He used a method to identify animals by photo identification. Shapes and pattern of flukes of each humpback whale is different like human's finger prints. The purposes were to study status of the species in Northwestern Pacific Ocean and to introduce the method to Japan.
At present in the oceans of our earth there are seventy-six varieties of whales and dolphins comprised of sixty-six kinds of toothed whales and ten varieties of baleen whales. Among those that can have confirmed sightings in the seas off Okinawa are nineteen varieties of toothed whales and seven varieties of baleen whales. One of the most frequently sighted among the baleen whales is the Humpback. The Humpback Whales in the Pacific
In order to win females to pair up with as mates, male whales engage in repeated fierce battles amongst themselves. At certain times as many as two to eight males will accompany one female. The male humpbacks do this to propagate their species and for them it is serious business, but for whale-watchers it is a chance to have an unforgettable experience viewing this dramatic behavior. The seas off Zamami Island are mating seas for the humpback and in contrast to other sea areas, such as feeding seas where such behavior as bubble net fishing can be seen, the Zamami seas are where visitors can come to watch their mating pod behavior.
Humpbacks usually congregate in small groups of one to four but gather in much larger groups when they are in the seas where they feed. Humpback Whales are popular among whale-watchers because of their dynamic performances. Whale Singing