Welcome to The Gray Whale Page!
A student web page designed by Robin Dale

Physical Appearance
Gray whales are relatively large, twice the length of a killer whale, and half the length of a blue whale. Adult gray whales are 10-13m (35-45ft), with an average length of 11m (39ft). They weigh 22-38 tonnes (20-35 tons). Females whales are usually larger than male whales. The record whale was 15.5m (51ft) and 42 tonnes (39tons).

Gray whales have a long and narrow shape and are a medium gray colour marbled with lighter patches. At the water surface they appear to be a whitsh-blue colour. Each whale has its own unique skin pattern which allows for identification. Their skin is smooth, and feels like a hard-boiled egg without the shell. Their head is quite long - one fifth the total body length - and it arches downward. The eyes of gray whales are brown and about the size of on orange. The snout and jaw have many short coarse bristles, 50 on top and 100 on the bottom. They steer themselves with their pectoral fins and power themselves with their tail. The tail can measure 3m (9ft) across and can weigh up to 180kg (400lbs)

Classification
Whales used to be classified as giant fish, even today whales are often administered by fisheries departments instead of wildlife departments. In 1693 John Ray classified whales as mammals, and centuries later (1864) Gray Whales were given the scientific name Eschrichitus robustus. They’re classified in the order Cetacea, which comes from the Greek work ketos, which means sea monster. Gray whales are a type of baleen whale, and has its own family which is Eschrichtiidae. They have many nicknames, including California whale, desert whale, devilfish, hardhead, and clam digger.

Migration
In the winter the whales live down in California and they migrate up to Alaska for the summer. They start to head down to California in early October, making their migration one of the longest of all animals. They end up in lagoons on the west coast of Baja California. Travelling through day and night, they cover about 125km (82miles) each day. They take 6-7 rests per day, each of which is about a half hour long. By December the Grays reach Baja where mating takes place, females impregnated the previous year give birth. After winter is over they start to head north for the summer. They migrate in groups of 1-5, and occasionally in groups up to 18. The mature whales leave first, followed by juveniles. Mothers with their calves are the last to leave which is about March. A few can still be found in May though. Their trek back up north isn’t as fast as on the way down because their isn’t the need for the females to give birth.

Some of the whales end up staying off the coasts of California, Oregon, Washington, and British Columbia. The largest group of summer residents are usually found off Vancouver Island, where 30-50 grays stop to spend the summer. Many of them have been given names which relate to their appearance. For example, Two Dot Star has two white patches on his back, and Prop has scars form a boat propeller.

Senses
Hearing is the most important sense for whales. In water, sound travels four times as fast as in does in air and it also travels further. Some of the sounds whales make can be heard above water. Fishermen used to think that their moans and whistles were sea monsters or mermaids. They vocalize using clicks, groans, grunts, squeaks, rasps, and roars. These sounds are produced by squeezing air through the blowhole, or by bursts of air from the lungs.

Sight
Since their eyes are far back on their head, gray whale vision consists on two fields on either sides of the body, rather than the binocular view that humans have. There is some uncertainty about how well whales can see because their eyes are very small, although they seem to have good eyesight in both water and air. It’s unknown whether whales can see colours or not.
A whale researcher, Rod Palm, once saw a young gray whale in shallow water close to a beach. When he walked down the beach, the whale followed along in the water. When he changed direction, so did the whale. Then the whale pushed itself onto the beach and looked at Palm, then went back into the water.

Food
Gray whales are mostly bottom feeders. They swim to the bottom of the ocean, roll onto their side, and stick their head a few inches into the bottom. They expand and contract their throat grooves, and retract their tongue (which may weigh 1300kg!), which creates suction that brings mud into its mouth. The mud is moved around a little and pushed out through the baleen.. The food gets trapped by the baleen and the rest is pushed out the sides of the mouth.
In some areas you can walk out at low tide and see huge pits in the bottom mud which are up to 3m (10ft) long. The food they get from the bottom includes amphipods, isopods, gastropods, bivalve molluscs, worms, and hydrozoans. As much as 90% of it is amphipods. The whales also feed on floating and swimming organisms. This includes shrimp, herring roe, tube dwelling worms, plankton, squid, small fish, crab larvae, shoals of red crabs, small crustaceans, and sometimes kelp. Most likely they eat kelp to help ease intestinal upsets, or stomach aches, just like a dog eats grass. On average they eat a ton of food a day.

Predators and Diseases
A natural predator of gray whales is the orca, or killer whale. The transient orcas eat young gray whale calves. Gray Whales are also bothered by small parasites and barnacles. "Whale lice" are often found crawling among the barnacles, which feed on dead skin. These are so common that the adult gray whale carries several hundred pounds worth of them. They can remove the parasites by rubbing on gravel on the ocean bottom, or entering coastal lagoons and the mouths or rivers (fresh water kills their marine parasites).

Whales can get cancers, stomach ulcers, heart disease, pneumonia, jaundice, and arthritis. Sometimes whales are found stranded on beaches, possibly from illness, wave action, currents, or parasitic infestations/diseases which affect the whales’ ability to navigate.

Whales have been hunted by humans for hundreds or years. In 1854 hunts began taking gray whales of the lower coast of California. The hunt didn’t boom until 1858, at which time began a rapid decline of gray whales in North America. In 1969 the United States added 8 species of whales to the Endangered Species Act, one of these was the California gray whale. This helped to shut down whaling businesses, from lack of demand from people for whale products. The gray whale population started to recover slowly. In 1994 gray whales were removed form the endangered list The only gray whales legally taken today are by aboriginals in Alaska and the Russian Republic. In October 1994, the IWC gave Washington State’s Makah Native tribe permission to kill 4 gray whales each year. Conservationists have threatened to file a law suit to stop the hunt, saying that the proposed use of high-powered rifles hardly qualifies as a traditional native hunting method.

click here for recent news on gray whale population estimates

Gray whales may also be dying from waste and chemicals dumped into the oceans. Businesses and cities dump sewage, garbage, chemicals, nuclear waste and more into the oceans, perhaps thinking that it will go away. But it is destroying oceans and the creatures living in them. The city of Vancouver alone dumps over 756 million litres of sewage into the ocean every day.

If the waste doesn’t affect the whales right away, it may get to them when they eat smaller fish and organisms which carry toxins in them. Fish nets are another hazard that may trap whales, holding them under the surface so that they can’t breathe.

Noise pollution is another problem - whales use sound primarily to observe their world. Gray whales may be quite effected by the continual sound of the heavy boat traffic that exists on their migratory routes.

Marine Mammal Center - gray whale page

Vancouver Aquarium Aquafacts

Gray Whale Migration

Questions and answers about baleen whales

 to marine biodiversity index