by L.S. Watts

Created on: June 12, 2009   Last Updated: June 13, 2009

The Gray Whale (Eschrichtius robustus) was once known as the Devil Fish because of its fierce hunting methods and its ability to overturn boats when they feel threatened. However, the Gray Whale isn't a fish at all. It must surface for air to breathe just like other marine mammals.

Appearance

As you might have guessed, this whale gets its name from the coloring of its body. It is gray in color with white spots. Many times you will see barnacles and several scratches along the body. Sometimes you will even see spots of orange, but this is due to whale lice. Gray Whales have long, streamlined bodies that taper and narrow at the head. The upper jaw is arched and slightly overlaps the lower jaw. On the ventral jaw, lower jaw, there are two to five grooves that are approximately five feet in length.

The Gray Whale does not have a dorsal fin, but instead it is more of a dorsal hump located two-thirds the way down its back. Located right behind the dorsal hump is six to twelve dorsal knuckles. It also has paddle shaped flippers that come to a point at the end. Its fluke, or tail fin, can reach ten to fifteen feet. These whales can grow to lengths of forty-six feet and weighing in at thirty to forty tons. The female are typically larger than the males.

Being a baleen whale, it has a approximately 130-180 fringed overlapping plates hanging from each side of the upper jaw, where teeth would normally be located. These plates consist of a keratin that fray out into fine hairs inside the mouth close to the tongue. These plates are off-white in color and about two to ten inches in length.

They have layer of blubber that is approximately ten inches thick to keep them warm in frigid water temperatures. They also have hairy bristles, called vibrissae, located on their snout that acts as tactile sensors.

Life Cycle

Gray Whales typically reach sexual maturity between 5 -11 years of age. Mating can occur at any time of the year, but generally happens during the 3-5 month mating season when they make the southward migration. Pregnant females tend to lead the migration. Courtship and mating behaviors is complex with these whales and there is general three or more whales involved in the mating process.

Gestation for these whales lasts for 12-13 months. When the calf is born it is dark gray, weighing approximately 1,100 - 1,500 pounds and is about 15 feet in length. These calves will be nursed for 7-8 months on milk that is 53 percent fat. Once they have reach 7 months the

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