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the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Fraser’s Dolphin

“Lagenodelphis hosei”

Fraser’s Dolphins are stocky cetaceans with short but distinct beaks. In 1895, Charles E. Hose found a skull on a beach in Sarawak, Borneo. He donated it to the British Museum where it remained unstudied until 1956, when Professor Francis Fraser examined it and concluded that it was similar to species in both the genera Lagenorhynchus and Delphinus but not the same as either. A new genus was created by simply merging these two names together. The specific name is given in Hose’s honor. It wasn’t until 1971 that the whole body of a Fraser’s Dolphin, as it was by then becoming known was discovered. At that time, washed-up specimens were found on Cocos Island in the eastern Pacific, in South Australia and in South Africa. Adults measure about 2 meters in length and weigh up to 210 kilograms. They have small, falcate (triangular) dorsal fins and small flippers and flukes. Their color varies with age and sex. Adults display a black stripe that extends down the length of their body, which is wider in adult males, absent or faint in juveniles and variable in adult females. They also have striped marking on their faces. They are brown-gray in coloring with a lighter ventral (under) side. Fraser’s Dolphins form large pods consisting of hundreds and sometimes thousands of individuals. These pods are often mixed with other cetaceans including Short-finned Pilot Whales, Risso’s Dolphins, Spinner Dolphins, Bottlenose Dolphins and even Sperm Whales. In terms of human interaction, Fraser’s Dolphins have been described as a shy dolphin in some areas, but more approachable in others.

Fraser’s Dolphins can be found off the coasts of Brazil, the Canary Islands, Japan, the Gulf of Mexico, Peru, Uruguay, Venezuela, West Africa, South Africa, Sri Lanka, Taiwan and Australia. The distribution and population of this species is not well-known, however Fraser’s Dolphins appear to be more common near the equator in the eastern tropical Pacific. They seem to be relatively scarce in the Atlantic Ocean, although they are seen from the Lesser Antilles, the Gulf of Mexico and Venezuela. Infrequent sightings have been reported in the Indian Ocean near the east coast of South Africa, Madagascar, Sri Lanka and Indonesia. Fraser’s Dolphins are generally found in offshore waters, however they have been seen near shores surrounded by deep water such as near Indonesia, the Lesser Antilles and the Philippines. Fraser’s Dolphin strandings have been reported in temperate areas, which may have resulted from El Niño events in 1983-84. Fraser’s Dolphins feed on deep water species, often diving to depths of 250-500 meters to feed on mid-water open ocean fishes, shrimps and squids. Fraser’s Dolphins are thought to give birth to calves in the spring and fall following a gestation period of about 12.5 months. Newborns measure about 110 centimeters in length. Fraser’s Dolphins populations are estimated to total about 289,500 in the Pacific Ocean. Small numbers of Fraser’s Dolphins are harpooned by subsistence hunters in the Indo-Pacific. This species has been harpooned by commercial interests selling their meat for bait and human consumption. Fraser’s Dolphins are caught as by-catch by purse-seines used by the tuna fishery in the eastern Pacific and some have been caught in gill nets in Sri Lanka and the Philippines. Dolphin hunting was banned in the Philippines in 1992, which has reduced the sale of dolphin meat on the open market.

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