Scientific Name: Phocoenoides dalli
See Dall's Porpoise
Curious Dall's Porpoise Science
When is the best time to view Dall's Porpoise in Monterey Bay and where is the best viewing?
Dall’s porpoises are found year-round in Monterey Bay, but are most prevalent during the spring and winter months. They can be seen swimming offshore, open water and inshore. Dall’s porpoises are most often seen in Monterey Bay over the canyon because they prefer water that is at least 600 feet deep.
The best chance of spotting Dall’s porpoises is from one of several whale watching boat excursions leaving daily from Fisherman’s Wharf or Moss Landing. Some boats going fast enough may find Dall’s porpoises riding its waves.
About Dall's Porpoise
This species was named after in honor of the American naturalist William H. Dall. He found and presented the first specimen of this porpoise.
Dall’s porpoises are short, yet robust. Male Dall’s porpoises are much thicker than the females. Dall’s porpoises have black and white markings similar to an orca, and are sometimes mistaken for a young orca.
Unlike other cetaceans, Dall’s porpoises have black or dark blue irises and blue-green pupils. Their teeth are also unique in that between each tooth, there is a “gum tooth”. As their spade-shaped normal teeth are small, the gum teeth may be helpful in catching and holding onto slippery prey such as squid. These porpoises mainly feed at night as their prey travels closer to the surface at this time.
When Dall’s porpoises swim quickly towards the surface, their head and back create a unique bow wave called a “rooster tail”. What appears to be just a splash is actually a hollow cone enabling the porpoise to breathe under the surface of the water.
Dall's Porpoise Fun Facts
- Have colored irises and pupils
- Fastest among small cetaceans, can swim up to 34 mph
- Can dive up to 1,640 feet
- Swim in groups of 2–20 individuals
- Whole body never comes all the way above the water
Habitat: Throughout the North Pacific Ocean from Southern California to Alaska and across to Japan
Length: Averages 6 feet; males can grow up to 8 feet
Weight: Averages 270 pounds; maximum weight 480 pounds
Diet: Small schooling fish like anchovies, herring, mackerels and sauries; Cephalopods like squid, octopus and cuttlefish
Lifespan: 15–20 years
Reproduction: Become sexually mature at 3.5 – 8 years of age; gestation lasts 10–12 months; females give birth to one calf at a time between June and September