From Jonah’s whale to Moby Dick, man has created and perpetuated many myths about the mysterious whale. And the biggest rumor of all is true.
Whales are indisputably the largest animals to ever inhabit the earth. Blue whales are even bigger than dinosaurs.
How big are they? That’s hard to know, since whales are shy about jumping on the bathroom scales. Historically, that scale was on a whaling vessel, where weighing was done in a hurry to make room for the next victim. Weights weren’t and aren’t always accurate, though it’s much easier to estimate a whale’s length. Blues are the longest at around 30 mtrs (100 ft) long.
Blue whales are found in Antarctica, along with Fin, Humpback, Killer, Minke, Sei, and Right whales. These whales belong to the Order called Cetacea – which means large sea creature – and cetaceans are divided into two sub-orders: baleen whales (Mysticeti) and toothed whales (Odontoceti).
All whales are carnivores, but the different species prefer slightly different diets. Blue whales are baleen whales, which means that the biggest whale actually eats the smallest animals.
Baleen whales mostly eat zooplankton, such as krill, by filtering massive amounts of these tiny creatures through comb-like plates that hang from their upper jaws. These whales have huge skulls that are specially adapted to this food-filtering lifestyle. A baleen whale’s skull can take up a third of its body length.
Each species varies some in the look, feel and specific function of its baleen. Coarse baleen that is spread wider apart filters out larger prey, and finer baleen that is closer together filters out smaller prey. The baleen itself is keratin, which isn’t really bone at all but the stuff from which fingernails and hooves are made. Whalers apparently didn’t care about the details, since they hunted “whalebone” (baleen) and sold it to manufacture human essentials such as umbrella ribs, corsets, and brushes.
Baleen whales are further divided into rorquals, which have grooves that run the length of their throats and expand during feeding, and Right whales, which feature extremely long baleen designed for dining while swimming.
Most baleen whales are rorquals. They include Minkes, Sei whales, Fin whales, Blues and Humpbacks. Right whales had the misfortune of being the “right” whale to hunt in the 19th and early 20th centuries.
Baleen whales have two breathing holes, and they can actually breathe at the same time they eat. This is a big deal if they’re also nursing calves.
Female baleens are bigger than the males, sometimes by up to 2 mtrs (6 feet). The females apparently need the extra size since they fast during winter migrations from feeding grounds to breeding grounds while suckling their calves.
Of 90 whale species, 76 are toothed and only 11 are baleen. Dolphins and porpoises, Orcas, and even Moby Dick (a sperm whale) are of the toothed variety.
Toothed whales have sharp teeth that are designed to grab individual prey animals. That means toothed whales hunt bigger prey than baleen whales do. Their diets include fish, squid, birds, mammals, and anything else they can catch. Orcas are called Killer whales for a reason. They hunt warm-blooded animals like penguins, seals, and even other whales.
Other than Sperm whales, most toothed whales are smaller and more agile than baleens.
Toothed whales use echolocation to hunt, much like bats do. Echolocation is the practice of emitting sounds that bounce off objects, thereby providing a mental picture of the animal’s environment. Whales emit clicks that echo back any change in their surroundings.
Toothed whales have only one blow-hole, unlike baleen whales. Most Odontocets have a fatty lens at the front of their heads called a melon. This melon might help focus and transmit echolocation sounds that are generated inside the skull.
Males are bigger than females, but both sexes tend to have battle scars from minor and major disagreements with others. Orcas can be sexed and identified by the shape, size, and saddle (white patch) of their dorsal fins.
Of course, some species are identified by their tails. Something we’re grateful is not true for us humans.
[TRIP TRIVIA: Visitors to Antarctica often get a close-up and personal look at whales, particularly Humpbacks and Minkes. Just don’t’ forget your camera when one spy-hops near your zodiac!]