Whale Migration

Information & Details

Whale Migration Details

Some of the whales and dolphins seen in our area, and the general migration patterns they have historically followed, are listed below. Links are provided to the American Cetacean Society for additional species information. Sightings, of course, vary from trip to trip, as well as through the seasons. If you want to see all the species possible in this area, you should consider joining us on several expeditions, at different times of the year.

Pacific White-Sided Dolphins (June – November)
  • These dolphins are distinctively marked, with black backs, white bellies and gray sides. They have white stripes running along their sides.
  • White-Sided Dolphins grow to about 7 or 8 feet long and weigh approximately 300 pounds.
  • These animals are often encountered in large herds of up to 100 individuals. They often escort boats for considerable distances and seem to love riding bow waves.
  • Mostly nocturnal feeders, White-Sided Dolphins eat small fish and squid.
Orcas SF Bay Whale Watching – Orcas

Orcas, not usually resident here, have been encountered in our local waters several times in the past few years. SF Bay Whale Watching passengers met a pack of 40 Orcas in the Gulf of the Farallones in spring 2009.

Adult male Orcas reach lengths of about 30 feet and may weigh approximately 16,000 pounds. Females are around 10 feet shorter and half as heavy.

Orcas are powerful and accomplished pack hunters, consuming a wide range of prey. Transients, such as those sometimes seen off our coast, often eat seals, porpoises, squid, sharks and even, sometimes, larger whales. Resident populations, like those in Puget Sound, eat more fish and fewer larger prey species.

The unmistakable triangular dorsal fin, which may be as long as 6 feet, together with the striking shiny black and white color pattern and white eye patches, make Orcas one of the most recognizable of all cetaceans.

Scientists studying resident Orca populations have learned that each pod (group) of whales uses a slightly different “vocabulary” of sounds, although many sounds are common to Orcas in general—just as English speakers in different regions have developed individual dialects of our shared language.

Gray Whales (December – May)

Gray Whales may be seen in the waters off our coast during both their migration from the Bering sea to their breeding areas in Baja California, which begins in October and takes two to three months, as well as during their return trip northward, which begins in the spring and lasts about the same length of time. Additionally, some individual Grays are seen during the summer months off the northern California coast.

  • Adult male Gray Whales reach about 45 feet in length, while females are slightly longer.
  • Grays of both genders typically weigh between 30 and 40 tons.
  • This whale owes its common name to the mottled gray and white patches on its skin. At birth, Gray Whale calves are darker than adults, sometimes even black.
  • Grays are bottom feeders, eating mostly crustaceans and other organisms found in ocean-floor sediments.
  • Gray whales produce a distinctive V-shaped blow, and usually blow several times, at short intervals, before diving for 3-5 minutes.
Humpback Whales (May – November) SF Bay Whale Watching – Humpback Whales Feeding
  • Adult Humpbacks range between 40 and 50 feet in length.
  • These whales travel alone, or in groups of up to to 10 individuals.
  • Humpback Whales blow up to 10 feet in short, bushy, balloon-shaped spouts. They may blow 4 to 8 times between dives.
  • Dramatic, graceful, often rotating breaches (in which whales “leap” partially—sometimes nearly fully—out of the water) have earned Humpbacks the nickname “ballerinas of the sea.”
Blue Whales (July – October) SF Bay Whale Watching – Blue Whale

Although sightings are not common (these giants are barely beginning to recover after the destruction of an estimated 99% of the worldwide population), we have recently seen as many as 3 Blues on a single trip!

  • These huge, seagoing mammals usually travel alone or in pairs.
  • In our Northern Hemisphere, they typically reach “only” 75-80 feet in length and may weigh over 100 tons.
  • Easily recognized because of their exceptional size and blue-gray color, Blue Whales also have distinctive U-shaped heads.
  • A Blue Whale’s blow (or “spout”), created when the warm, moist air from the animal’s lungs meets the cooler outside air, may rise up to 30 feet above the surface of the ocean.
  • After diving, Blue Whales can remain underwater for 10 – 20 minutes before resurfacing.
  • When these whales surface from long dives, they may blow 8 to 15 times, making short, shallow dives between blows.
  • Blue Whales raise their flukes (tails) before diving.
Harbor Porpoise

One of the smallest of the oceanic cetaceans, the harbor porpoise is shy and elusive, not inclined to approach boats and bow ride, as many other species of dolphins and porpoises do.

Maximum length is 6 feet (1.9 m) with a possible maximum weight of 200 pounds (90 kg).

The harbor porpoise eats non-spiny fishes such as herring, cod, whiting, squid, pollock, and sardines. It seems to require large amounts of food, consuming approximately 10% of its body weight each day.

Harbor porpoises may be seen singly or in pairs, or in small groups of 6 to 10 animals. Sightings have been reported of 50 to 100 in groups that were actively feeding.