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Common Bottlenose Dolphin


Animal Classification



Bottlenose dolphins are arguably the most recognized small cetaceans, but can be hard to distinguish from other wild dolphins. These animals are counter shaded: blackish, slate, gray, brown, or bluish on top, lighter on the sides; and whitish or paler pinkish gray underneath.Sometimes there are spots on the belly and a stripe between the eye and the flipper insertion. Bottlenose dolphins have short beaks, a non-marked melon, a single blowhole, and a moderately hooked dorsal fin. They have 18 to 26 conical teeth in each jaw and their brains are extremely coiled so much so that if it were to be spread out flat, the surface area would be greater than that of a human cortex. Males are a bit longer and more massive than females and mature at about 9 to 5 years and can live as long as 40 to 45 years. Females mature at about 5 to 12 years and may live longer than 50 years.The average life span for both male and female is around 20 years.


The Common Bottlenose Dolphin swims in all of the world's tropical and temperate seas. Some populations are strictly local; others migrate extensively. There are offshore and inshore populations as well. In California, coastal Common Bottlenose Dolphins stay close to shore between Cabo San Lucas to just north of San Francisco.


Birthing can occur anytime of the year, but generally peaks in the spring with a secondary peak in the autumn. A newborn dolphin is 3 to 4 feet in length and may weigh 33 to 66 lbs. after gestation of 11 to 12 months. When born, a second dolphin (male or female) may assist in the delivery and continue to associate with the young calf.


In the water, Common Bottlenose Dolphins make an incredible array of squeaks, grunts, grinds, and whines. These sounds fall into three categories: whistles, echolocation clicks, and pulse sounds. Additionally, dolphins communicate non-vocally through touch. Common Bottlenose Dolphins, like most dolphins, are highly social. They form many kinds of social groups; mother-calf pairs, bands of mothers, and large societies. Common Bottlenose Dolphins never fall completely asleep because their breathing is under voluntary control, When not resting, dolphins are among the fastest swimmers of all marine mammals achieving speeds up to 22 mph in bursts of speed. Common Bottlenose Dolphins eat a variety of fish as well as crabs, squid, shrimp, and similar prey.


The California Common Bottlenose Dolphin coastal population is estimated to be a mere 323 dolphins. The offshore bottlenose population within 300 miles of the west coast of North America may be more than 3,000, and to the south of the Mexican border, surveys have yielded an overall estimate of 336,000 dolphins.

At The Marine Mammal Center

The Marine Mammal Center rescued a bottlenose dolphin they later named Baker D, on September 15, 2004 at Baker Beach in San Francisco. At the time of Baker D's rescue, the three to four year old male cetacean was underweight, suffering from dehydration and had a puncture wound on his rostrum. When he was transported to a rehabilitation pool at the Center, he didn't have the strength to swim on his own and was put into a floating support sling to prevent him from drowning. Through antibiotics, medications to help stabilize his heart, and weeks of round-the-clock care and feedings from volunteers and veterinarian staff at the Center, Baker D regained his health and could swim on his own. Since July 2012, staff and volunteers have rescued 10 live bottlenose dolphins since 1975 and were able to successfully rehabilitate and release three of those animals, counting Baker D. back to the ocean.

When you symbolically adopt Baker D, you’ll receive a personalized adoption certificate with Baker D’s photo and story. You can make a difference in the life of a marine mammal like Baker D.

Source on this page: Field Guide to Marine Mammals of the Pacific Coast, 2011.

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