Lifecycle Of A Pacific Dolphin

Lifecycle Of A Pacific Dolphin

Knowing the life cycle of the dolphin, especially of the Pacific dolphin, can help researchers and scientists look for ways to protect these endangered animals. Many dolphins get killed annually after getting caught in fishing nets, getting hit by boats or for their meat. However, most dolphins have slow reproduction rate, which is just enough to add dolphins that die naturally. Hence, their numbers are dwindling fast in the wild. But, understanding the lifecycle of each species, such as the Pacific dolphin, it will give a better understanding of how to go about saving these cetaceans.


The Pacific white sided dolphin is found in those waters which are temperate. They can be spotted in the waters, ranging from Amchitka Island located in the north to Gulf of Alaska in the southern coastline of North America. This range extends all the way until Baja California.

There are approximately 900,000 dolphins inhabiting the northern part of the Pacific. In the Asian region, these are found to live in temperate water in the coastal area of Kuril Island up to Japan. It is estimated that the coastal region of Japan alone houses approximately 30 to 50 thousand dolphins.

Pacific dolphins have white color on the sides and belly. Their top has a central dark grey coloration and the sides are light grey colored strips which widens while progressing from the eyes to the tail. They also have dark rings surrounding their eyes and their beaks are small and dark in color.

The female in this species weighs approximately 85 to 145 kg and can be as long as 1.7 to 2.4 meters. The males in this species can weigh approximately 198 kg and can be up to 2.5 meters in length.

These mammals give birth to calves, which are approximately 15 kg in weight and 1 meter in length. These are nursed for a period of 8 to 10 months. Living in groups trains these calves for hunting and surviving at sea. The females tend to give birth to their offspring on reaching an age of 7 to 9 years old. The gestation period in dolphins is approximately 12 months. The cycle of delivering calves occurs once in every 4.5 to 5 years. Most calves are born during the months of June and August, especially in British Columbia.

These dolphins make ideal preys for sharks and killer whales. It was previously observed that pods of killer whales would attack the Pacific dolphins and corner them in bays. This would result in a carnage where the entire pod of the dolphins would end up being killed. However, this mode of killing is no longer seen and as a result the scientists believe that dolphins have learned to avoid killer whales.

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Lifecycle Of A Pacific Dolphin

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