Pacific White-Sided Dolphin (Lagenorhynchus obliquidens)
Did You Know?
- Pacific white-sided dolphins have an unusually large, falcate dorsal fin and are sometimes referred to as the "hookfin porpoise," even though they are not porpoises.
- Schools of thousands of Pacific white-sided dolphins are occasionally observed, but group size generally ranges from 10 to 100 animals.
CITES Appendix II - throughout its range
|300-400 lbs (135-180 kg)|
|5.5-8.0 feet (1.7-2.5 m)|
|their back, fluke (tail), and lips are black and their sides, dorsal fin, and flippers are gray, and their belly is white|
|more than 40 years|
|squid and small schooling fish such as capelin, sardines, and herring|
|extremely playful and highly social animals|
Pacific white-sided dolphins have a robust body and a very short beak. They have an unusually large, curved dorsal fin and are sometimes referred to as the "hookfin porpoise," even though they are not porpoises. Their back, fluke (tail), and lips are black, while their sides, dorsal fin, and flippers are gray. Their belly is white. On both sides of the dorsal fin, a white or light gray stripe, which resembles a pair of suspenders, extends from the eyes to the tail. Pacific white-sided dolphins can sometimes be confused with Dall's porpoise, which shares a similar distribution pattern. They are the only members of the genus Lagenorhynchusin the North Pacific Ocean.
The average adult Pacific white-sided dolphin weighs about 300-400 lbs (135-180 kg) and is between 5.5-8.0 feet (1.7-2.5 m) long. Males are generally larger than females, with males reaching an average length of 8 ft (2.5 m) and females reaching an average length of 7.5 ft (2.3 m). This species of dolphin can live for more than 40 years.
Pacific white-sided dolphins are extremely playful and highly social animals. Schools of thousands of Pacific white-sided dolphins are occasionally observed, but group size generally ranges from 10-100 animals. They are often observed "bow riding" and doing acrobatic somersaults. This species commonly associates with other cetaceans, such as Northern right whale dolphins and Risso's dolphins.
They prey on squid and small schooling fish such as capelin, sardines, and herring. This species is capable of diving more than 6 minutes to feed. They have small conical teeth that are helpful in grasping their prey. When feeding during the day, they can be seen working together as a group to herd schools of fish.Pacific white-sided dolphins reach sexual maturity around 7-10 years of age around lengths of 5.5-6 ft (1.7-1.8 m). Gestation lasts for 12 months with calves being born in the summer months. Calves weigh approximately 30 pounds (15 kg) and are about 2.5-4 feet (1-1.2 m) in length. Females give birth less than every other year. "pelagic" species ranges in the Western Pacific Ocean from the South Bering Sea to southern Japan. In the Eastern Pacific Ocean, they range from the Gulf of Alaska to the Gulf of California. They are most common between the latitudes of 38°N and 47°N. The distribution and abundance of Pacific white-sided dolphins may be affected by large-scale oceanographic occurrences, such as El Niño and by underwater acoustic deterrent devices. stock assessment reports with population estimates are available on our website. "taken" between 1978-1990 in gillnets and driftnets targeting squid by Japan, Korea, and Taiwan (Folkens et al., 2002). They are sometimes killed by harpooning and drive fisheries in Japan. Marine Mammal Protection Act of 1972 as amended. Marine Mammal Protection Act of 1972 as amended. Kingdom: Animalia
The Atlantic white-sided dolphin (Lagenorhynchus acutus) is another species of white-sided dolphin.
|Stock Assessment Reports||n/a||various|
- NMFS National Marine Mammal Laboratory Pacific White-sided Dolphin Information
- NOAA's National Marine Sanctuaries
- Listen to Pacific White-sided Dolphin Sounds from NMFS Southwest Fisheries Science Center Cetacean Sounds Collection
- Ocean Biogeographic Information System (OBIS-SEAMAP) Pacific White-Sided Dolphin Species Profile
- Reeves, R. R., P. A. Folkens, et al. (2002). Guide to Marine Mammals of the World. New York, Alfred A. Knopf. p. 402-405.
Updated: January 16, 2015