Known for their characteristic coloring and playful behavior, Pacific white-sided dolphins are one of the two types of white-sided dolphins, the other being the Atlantic white-sided dolphin. While both species almost resemble each other in appearance, the Pacific species is relatively smaller than its Atlantic counterpart.
The Pacific white-sided dolphins are commonly seen in social groups ranging from a few to several hundred individuals.
They may also accompany other dolphins such as the Risso's dolphins and the northern right whale dolphins.
Moreover, they are pretty surface-active and are often seen bow-riding off ships and boats, somersaulting, belly-flopping, leaping, and even spinning in the air. Due to their large and curved dorsal fin, these marine mammals are sometimes referred to as the hookfin porpoise even though they are not porpoises.
The Pacific white-sided dolphin has quite a remarkable appearance. While the body is dark gray to black, each side has a striking light gray or white patch.
The beak is thick, rounded, and relatively less prominent than that of most other dolphin species. The dorsal fin has grayish stripes underneath that broaden and meet along the tailstock.
In fact, the dorsal fin of this marine mammal is quite distinct in being curved, tall, and having a black leading edge fading to gray. The light-colored patches on the flanks of this marine mammal often lead to confusion with Dall's porpoises and common dolphins.
Pacific white-sided dolphins grace the cool waters of the North Pacific Ocean and the surrounding seas.
The species is resident of the cold Pacific waters, and their range extends between the 38 degrees North and 47 degrees North latitudes.
These marine mammals are found along the coast of North America as well as in the southern Bering Sea, the Sea of Okhotsk, the Sea of Japan, and East China and Yellow Seas to the south of Japan.
Pacific white-sided dolphins are carnivorous and feed on squid and small schooling fish such as anchovies, mackerels, sardines, and herring.
Read on for more such fun and interesting facts about the Pacific white-sided dolphins! For more relatable content, check out these bottlenose dolphin facts and striped dolphin facts for kids.
Pacific White-Sided Dolphin Interesting Facts
What type of animal is a Pacific white-sided dolphin?
The Pacific white-sided dolphin (Lagenorhynchus obliquidens) is a marine, carnivorous dolphin species of the Delphinidae family.
What class of animal does a Pacific white-sided dolphin belong to?
Pacific white-sided dolphins belong to the class of Mammalia.
How many Pacific white-sided dolphins are there in the world?
The latest global population size of the Pacific white-sided dolphin is not available.
Where does a Pacific white-sided dolphin live?
In the regions of temperate waters they inhabit, the range of the Pacific white-sided dolphins spans along the coast of North America and Asia.
Their range extends from the Aleutian Islands, south through to the Gulf of Alaska and up to the tip of Baja California.
They are also abundant in the southern Bering Sea, the Sea of Okhotsk, the Sea of Japan, and East China and Yellow Seas off the coast of Asia and southern Japan.
In May, the Pacific white-sided dolphins can be found off the coast of Washington and Oregon, and between November to April, they are found near the shores of southern California, suggesting seasonal migration.
These dolphins were earlier abundant in the Gulf of California as well, but their population declined there due to a rise in water temperatures.
What is a Pacific white-sided dolphin's habitat?
Pacific white-sided dolphins reside in the temperate waters of the North Pacific Ocean. They avoid the arctic and tropical waters and usually occur in areas between 38 degrees North and 47 degrees North.
Who do Pacific white-sided dolphins live with?
Pacific white-sided dolphins live in large groups of tens, hundreds, or even thousands. These groups or pods of dolphins are often seen catching schools of fish together.
Moreover, the Pacific white-sided dolphins frequently associate with other dolphins such as the Risso's dolphins, the northern right whale dolphins, common dolphins, and large whales. In terms of behavior, Pacific white-sided dolphins are very playful and energetic. These dolphins are often seen leaping, bow-riding, somersaulting, and even spinning in the air.
How long does a Pacific white-sided dolphin live?
Pacific white-sided dolphins have a lifespan in the range of 36-46 years.
How do they reproduce?
Pacific white-sided dolphins do not breed year-round as it is seasonal between August and October. The gestation period lasts for 9-12 months.
After the 9-12 months gestation period, the females give birth to a single offspring. Most of the Pacific white-sided dolphin females give birth between late spring and fall, except in the central Pacific, where the dolphins give birth between late winter and spring.
When the calves (baby dolphins) are born, they weigh about 30 lb (13.6 kg) and measure 3-4 ft (0.9-1.2 m) in length. The mother dolphins take care of their calves for up to 18 months after birth.
What is their conservation status?
According to the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, the Pacific white-sided dolphin (Lagenorhynchus obliquidens) is a species of Least Concern.
Pacific White-Sided Dolphin Fun Facts
What do Pacific white-sided dolphins look like?
Pacific white-sided dolphins are dark gray to black on the back with light gray to white sides. The belly is white.
Distinct white or light gray stripes begin from above the eye and run along the length of the sides, flippers, dorsal fin, and extending to the base of the tail. The dolphin's lips and beak are black, and there is a dark patch around each eye.
Moreover, the beak is short and rounded, almost indistinguishable from the forehead. Another distinctive feature is the dorsal fin which is tall, sharply hooked, and located in the middle of the back.
The leading edge of the dorsal fin is black that fades into a light gray shade towards the rear. The flippers are comparatively smaller, curved, and rounded at the tips and the flukes have a notch in the center.
How cute are they?
The short and rounded beak of the Pacific white-sided dolphins lends them a cute and adorable appearance. Besides, their belly is white, which, in contrast to the darker back, makes the dolphins look extremely beautiful.
How do they communicate?
Pacific white-sided dolphins use echolocation to locate prey. It is a phenomenon whereby the dolphins perceive the sound reflected from a target to determine the latter's location. Like the Atlantic white-sided dolphins, their Pacific counterparts use whistles to communicate among themselves. The signature high-frequency whistles are unique to the species.
How big is a Pacific white-sided dolphin?
The length of adult Pacific white-sided dolphins ranges between 7.5-8.2 ft (2.3-2.5 m). They are similar in length to the common dolphins. In comparison, the northern right whale dolphins measure between 6.6-9.8 ft (2-3 m).
How fast can a Pacific white-sided dolphin swim?
Pacific white-sided dolphins are known to have swimming speeds of up to 20 mph (32.2 kph). These marine creatures are strong and fast swimmers with the ability to bow-ride with extended vessels for prolonged periods.
How much does a Pacific white-sided dolphin weigh?
Pacific white-sided dolphins weigh between 330-440 lb (149.7-199.6 kg).
What are the male and female names of the species?
A male dolphin is called a bull, and a female dolphin is called a cow. Hence, like any other dolphin, Pacific white-sided male and female dolphins are referred to as bulls and cows respectively.
What would you call a baby Pacific white-sided dolphin?
Like any other species of dolphin, Pacific white-sided dolphin babies are called calves.
What do they eat?
Pacific white-sided dolphins are opportunistic feeders and prey on squid and small schooling fish. Their diet comprises fish such as anchovies, mackerels, capelins, sardines, and herring.
An adult Pacific white-sided dolphin can consume up to 20 lb (9.1 kg) of food per day! The dolphins have small conical teeth, 23-36 pairs in each row, which helps them to hold on to prey.
Instead of chewing their food, these dolphins swallow their prey whole, head first, to avoid the fish spines from getting stuck in their throat.
Are they dangerous?
Pacific white-sided dolphins are not known to be dangerous. However, they disrupt commercial fishing activities on the high seas and often become entangled in fishing nets.
Would they make a good pet?
The Pacific white-sided dolphins are wild animals adapted to a specific habitat and carnivorous diet. Hence, they are not suitable for keeping as pets. Besides, the dolphins are protected under the Marine Mammals Protection Act (MMPA), making it illegal to own one.
Did you know...
One of the ocean's most acrobatic animals, Pacific white-sided dolphins can jump as high as 20 ft (6.1 m) in the air.
The scientific name (Lagenorhynchus obliquidens) of the Pacific white-sided dolphins was given by mammologist Theodore Nicholas Gill. Recent studies have suggested a new genus, Sagmatias, which has been accepted by the American Society of Mammologists.
Are Pacific white-sided dolphins endangered?
Pacific white-sided dolphins are not endangered. While the dolphins are no longer commercially hunted in the United States, their life faces constant threats due to pollution and entanglement with commercial fishing gear.
Low-frequency noise pollution underwater significantly interrupts the normal behavior of Pacific white-sided dolphins and interferes with their ability to find food, communicate, navigate, choose mating partners, and avoid predators. Moreover, the dolphins frequently get captured in commercial fishing gear such as seines, gillnets, trap pots, trawls, and longlines.
What eats Pacific white-sided dolphins?
Known predators of Pacific white-sided dolphins include humans and orcas. These dolphins are often captured by Japan's coastal fisheries for their meat.
Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other mammals from our eastern cottontail fun facts and interesting pyredoodle facts pages.
You can even occupy yourself at home by coloring in one of our free printable Australian humpback dolphin coloring pages.
Second image by NMFS Southwest Fisheries Science Center (NOAA).