Gray Whales: Just The FAQs

whaleinglassesSuhail Rafidi’s forthcoming novel, Cetus Finalis: A Gray Whale Odyssey (Available September 2016), tells the journey of a pod of endangered Atlantic gray whales searching for their mates. In order to provide some background for the interested reader, we have some some interesting scientific facts about gray whales.

Whales are warm blooded mammals that live exclusively in the sea. They have an internal body temperature similar to ours. To maintain mammalian body temperature in a vast, cold ocean, they have evolved many fascinating adaptations, like blubber. They employ highly sophisticated breathing and sound processing techniques, and possess generationally transmitted intelligence; forming what we may call culture and society. Gray whales in particular are unique in the world of whales because they prefer to live near shore in shallower waters, and they are the only whales who are almost exclusively bottom feeders. Now for the questions!

Why are they called gray whales?
From their body coloration; gray skin accented by white barnacles and mottled patches of white where barnacles have dislodged. It is also common to see patches of orange whale lice.

How do I visually recognize a gray whale?
First, look for the whale’s spout when it surfaces. Because of the position of their dual blowholes (like our nostrils, but with muscle control, and on the top of their heads), a gray whale spout has a heart or V-shape to it. Gray whales’ streamlined bodies are marked by a few (2-5) ventral grooves along their throat.nicegray-whale-med These are pleats that spread open when the gray whale feeds, allowing it too scoop more sea bed. Grays have hatchet tapered rostrums, and a slight overbite, with their upper jaw overlapping the lower slightly. Another helpful visual characteristic is revealed when you watch a gray whale dive. Look at their backs and notice that gray whales do not have a dorsal fin; look instead for a dorsal hump, followed by 6 to 12 dorsal knuckles on the ridge behind the hump. Watch also for the fluke (whaleish for ‘tail’). The gray whale’s fluke is about 3-4 meters (10-12 feet) across, with a deep notch in the center, giving it a fan shape.

What is gray whale skin like?
Gray whale skin is described as feeling like a mushroom or a peeled hard boiled egg. Some of their skin is crusted with barnacles and clusters of orange whale lice, which eat the microorganisms and bacteria on their bodies. Most adult grays have raking and scar marks from orca encounters.


gray_whale_spyhop_chris_johnson_noaanmfs_swfscHow long can gray whales hold their breath?
Gray whales can hold their breath for 20 to 30 minutes. Unlike land mammal physiology, whale breathing is a voluntary action. This means they have to consciously control their breathing at all times. Consequently, a whale could never sleep for hours because it would drown. (Human breathing is an involuntary action, it happens automatically whether we think about it or not. Though when we do think about breathing, we gain a lot of range. Ask any diver or yogi.)

When do gray whales sleep?
There are a couple of scientific theories about whale sleep. One is that gray whales might sleep while swimming, effectively sleeping while in cruise control. Another theory is that whales ever take naps, typically submerged, for approximately as long as they can hold their breath, 20 to 30 minutes.

How big do gray whales grow?
Gray whales can grow to weigh 30 to 40 tons and be as long as 45 feet. Female gray whales grow larger than their male counterparts, reaching 50 feet.

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Do gray whales sing?
Yes, gray whales sing. They use various low frequency warbles and gurgling sounds. No one yet understands the exact meaning of whale song, but there are a lot of good guesses. (Ahem, Cetus Finalis)

What are gray whales’ eyes like?
Eye of a Gray Whale, grey whale
The eyes of an adult gray whale are approximately the size of a baseball, and situated above the whale’s jaw. Gray whale eyes are very similar to human eyes and can see about as well. (If you’ve ever tried to see underwater, this might give you an idea why sound is so important to  whales.) A dead gray whale’s age can be determined during an autopsy by the quantity of a certain protein in its eyes.

What is the average life span of a gray whale?
Gray whales typically live between 40 to 60 years, though they can live as long as 80 years.

How long is gray whale childhood?
Gray whales usually hit puberty somewhere between ages 5 and 11. Given a typical lifespan, one female gray could give birth as many as 18 times.

How long is a gray whale pregnant?
Gray whale gestation is one year. Reproductive cycles are closely linked with migratory cycles, because it is best for mothers to give birth in warmer waters. Possibly for this reason, gray whales have adapted something called delayed implantation. A gray whale’s embryo does not begin to develop in the mother’s womb until some months after she has become pregnant (which usually happens at the birthing grounds). This presumably gives her a chance to have one arctic feeding season while pregnant so she can eat for the baby and still get back to warm waters in time to give birth.

GrayandCalfBodyLabelsSmall

Are gray whales attentive mothers?
Yes, gray whales make good mothers, being rather protective of their calves. In fact, one of the old nicknames for gray whales, “devilfish,” was derived because of the violence mothers were capable of when whalers killed their babies, including sinking entire whaling ships.

What are newborn gray whales like?
Newborn gray whales are dark in color, sometimes black, with the distinctive white patchy markings of their kind. They are born weighing between 1,000 to 1,500 pounds, and are about 15 feet in length. They are born with very little blubber and must spend 2 to 3 months in the shelter of the warm lagoons, feeding excessively on their mother’s nutritious, fatty milk (52% fat) until they plump up enough to make the trip north. Baby gray whales nurse for 6 to 8 months, consuming 50 gallons of mother’s milk daily.

What happens after a baby gray whale is born underwater?
The baby needs air, but can not yet swim. So for its first few breaths, its mother will give it a natal lift on her rostrum, bringing the baby to air. Within a couple hours of birth, the calf is able to swim and stay afloat on its own. Though when it tires, it is liable to rest on its mother’s flippers or back.

What is a gray whale’s diet?
Gray whale feeding in the mud flats near Tofino, Canada, 1984
Gray whales eat small shellfish, crustaceans, copepods, amphipods and tube worms embedded in the sediment on the sea floor. Grays sift the fauna out of sea bed silt in the same way that cattle crop an open range. When the food runs low, they move on. To feed, they dive to the bottom, roll onto their right side, and scoop mouthfuls of sea bed sediment. When they close their mouths, the water and mud are squeezed out through their baleen, leaving the food behind in their mouths. They scrape it off the baleen with their tongues and swallow.

How fast are gray whales?
Gray whales swim an average of 3-6 miles per hour. When migrating they cover about 100 miles per day.

Gray Whale Calf, San Ignacio LagoonHow far from shore do gray whales travel?
Gray whales hug the coast, staying within 5 miles of shore. Gray whales pay more attention to the depth of the water than their distance from shore.

When do gray whales eat?
Gray whales do the bulk of their feeding during summers in the arctic. Some suggest that this is the only time gray whales eat; they build up their fat reserves up north, then fast for months during the warm mating times at the southern lagoons.

How much weight do gray whales lose during their non-eating times?
A lot. Migration, mating, and nursing use up a great deal of energy. A 30-ton gray whale, for example, might lose as much as 11 or 12 tons of blubber weight during the breeding grounds and migratory parts of their year. So when they get back to the arctic feeding grounds, they really do have their work cut out for them.

Are gray whales endangered?
In 1994, the Pacific gray whale was finally removed from the endangered species list. The Atlantic grayGray_whale_skeleton whale became extinct in the late 1700s or early 1800s and is the only population of whale to ever be wiped out. Although, in 2010, a gray whale was sighted in the Mediterranean Sea. Subsequent scattered sightings off the coast of Africa, near Namibia, and far flung parts of the Pacific indicate that gray whales are migrating farther than ever before, and could possibly be reentering the Atlantic ocean after hundreds of years. This recent unexpected and unprecedented evidence of whale migrations may also be related to global ecological and climate changes.

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