We have covered many animals, large and small, in our “Wildlife of the Week” segments. However, there is one impressive marine mammal we have not yet highlighted! The Gray Whale (Eschrichtius robustus) is a baleen whale that can be seen along the West Coast, however it is seen less frequently in our region of the Salish Sea (than say, a Humpback Whale or orca). The Gray Whale is a fascinating leviathan of the deep, and sets itself apart from other cetacean giants with some unique characteristics of its own. To learn more about the Gray Whale, follow along below!
The Gray Whale ranks alongside some of the biggest marine wildlife of the Salish Sea. Weighing in between 25-40 tons (50,000- 80,000 lbs.), the Gray Whale is no small creature! They reach lengths of 39-46 feet long (12-14m). The Gray Whale is accurately named for its body colour, which is usually a mottled and patchy mix of white and gray. The whale has a tapered, pointed body shape and is often covered extensively in barnacles and sea lice. The Gray Whale does in fact have a small dorsal fin (arguable) along a bumpy dorsal ridge on its back. These bumps are referred to as “knuckles”. Like all baleen whales, the Gray Whale has two blowholes to breathe.
The Gray Whale is a primarily Northern Hemisphere coastal species, often observed close to shore. The animal is found in the Bering and Chuchki Seas to Baja California, waters around Asia, within the Salish Sea and areas off northern California. Northern areas support summer feeding, whereas southern areas provide areas for winter breeding. The eastern population mainly follows the West Coast route, from Alaska to California or Mexico.
The western population has feeding grounds near Sakhalin, Russia and southern grounds in the South China Sea. All Gray Whales complete impressive migrations annually, distances of up to 10-14,000 miles (16,000-22,530 km) between these two grounds. Winter grounds provide warmer and shallower water rather than the cool, nutrient-rich waters of the north.
The Gray Whale is mostly a bottom-feeding specialist, capable of accessing hidden prey in sediments. A baleen whale, the Gray Whale does not have teeth and instead relies on baleen plates (130-180 plates), primarily composed of keratin. These plates, on the upper mouth, act as a filter to capture tiny creatures out of seawater. The Gray Whale scrapes its mouth along the bottom, swimming on its side and dredging up buried creatures as it does. The water is forced out the mouth behind the animal and the prey is consumed off the baleen. Prey sources mainly include amphipods, small crustacean and tubeworms.
Interestingly enough, Gray Whales’ heads will show a “handedness”; that is, one side will show its preference for feeding via disproportionate scratches, wear and noticeable use.
Gray Whale reproduction, as mentioned, occurs in the summer at breeding grounds, however mating may occur during travels as well. Gestation for Gray Whales is a lengthy 12-13 months! Newborn calves are large at 1,100-1,500 lbs. (500-680 kg). Females will bear calves every several years on average.
Mostly known as a solitary species, the Gray Whale is often spotted travelling alone. If with others, these are usually small and temporary groups of individuals. In this species, females are physically larger than males. Gray Whales are subject to predation from orcas, and must be careful with their calves in areas where orcas might be present as young animals are vulnerable due to their smaller size and lower swimming stamina. As with many other large cetacean species, Gray Whales have long lifespans, and although still unclear, ages may reach 75-80 years in females.
Gray Whales, like other marine species, are at risk from habitat change, pollution and other forms of human impacts. These include entanglement in human gear and oceanographic variabilities such as sea ice changes, changing temperatures and currents and factors creating prey stress. Offshore oil and gas development may also negatively alter habitat. Being large animals that are often present in busy traffic areas, Gray Whales cannot always recognize the presence or direction of large vessels, or move out of the way quickly enough (they might even surface at an inopportune time); thus this species may be subject to dangerous strikes from ships.
There are several initiatives, many initiated and/or encouraged by whale-watching companies such as Five Star, that work to protect marine species by acting as sentinels and examples of respectful boating behaviour.
Feeling Gray Whale savvy? Try out your Gray Whale knowledge with some trivia below!
- What is a historical nickname for the Gray Whale? (ANS: “Devilfish”. Due to their pronounced reactions to being harpooned in whaling times).
- The tail of the Gray Whale may measure up to _____ feet wide (ANS: 10).
- A piece of Gray Whale baleen is called a ______ (ANS: Whalebone).
Fill in the letters/word. Historical uses for whalebone included c_rset_ and umbrella ____.
Corsets and umbrella ribs.
Article Authored By: Alexa Desautels, B.Sc./ Five Star Whale Watching
To learn more about the Gray Whale, check out our References below!
“Gray Whale”. American Cetacean Society. 2017. Gray Whale (acsonline.org).
“Gray Whale”. National Geographic Society. Gray Whale | National Geographic.
“Gray Whale”. World Wildlife Fund. Gray Whale | Species | WWF (worldwildlife.org).
“Gray Whale”. NOAA Fisheries. U.S. Department of Commerce. Gray Whale | NOAA Fisheries.