Whales are marine mammals, members of the cetacea order which also includes dolphins and porpoises.
They are divided into two suborders: baleen and toothed whales.
The most important trait of toothed whales is what gives them their name: they have teeth. This is the easiest difference to spot between baleen and toothed whales.
There are currently 15 species of baleen whale.
There are about 72 different species in toothed whale suborder. But in addition to whales the toothed whale suborder also consists of all species of dolphin and porpoise.
The blue whale (Balaenoptera musculus) is a marine mammal belonging to the baleen whales. At up to 30 meters (98 feet) in length and with a maximum recorded weight of 173 tonnes (191 short tons) and probably reaching over 181 tonnes (200 short tons), it is the largest animal ever known to have existed.
The dwarf sperm whale (Kogia sima) is the smallest species commonly known as a whale. It grows up to 2.7 meters (8.9 feet) in length and 250 kilograms (550 pounds) in weight— making it smaller than the bigger species of dolphin.
Whales come in different sizes, but they all have smooth skin, flippers, and flat tails (called flukes) that propel them through the water.
Various scientific studies have calculated life expectancy averages of various species to range anywhere from 30 – 70 years all the way up to 200 years for species such as the bowhead whale that are in top physical health.
The social structure for whales is one that is very interesting. They are avid communicators. A group of whales that live together is known as a pod. They do almost everything together including hunting and migrating. They size of the pod can vary from only a few whales to about twenty. Some species of Baleen Whales have been known to live alone though rather than as part of a pod.
Whales communicate through their complex and mysterious sounds. They make lots of different kinds of sounds, including trills, whistles, moans, and squeals. Whistles seem to be used mainly for communicating with other whales. Single male humpback whales make their famous whale songs using melodic sounds during the winter mating season.
Toothed whales have developed the capability of emitting sounds that travel from their melons (or foreheads) and reflect off objects. Like bats, odontocetes use this echolocation process to gather information in order to “see” the world around them. Submarines use the same method to navigate through the ocean.
Whales have lungs and the blowhole on top allows air in, and out, like a nostril. Baleen whales have two blowholes, located side by side. Toothed whales have one blowhole. The blowhole can be closed voluntarily so that the whale doesn’t inhale water.
Although the amount of time that a whale can hold its breath varies by species, the beaked whale can hold its breath for up to 2 hours. The sperm whale can hold its breath for up to 90 minutes and the humpback whale can hold its breath for 45 minutes.
Whales have to be conscious to breath. This means that they cannot go into a full deep sleep, because then they would suffocate. They have “solved” that by letting one half of their brain sleep at a time. This has been determined by doing EEG studies on dolphins.
They can rest, horizontally or vertically, in the water, or they can sleep while swimming exceptionally slowly.
Baleen whales use baleen to strain food from the water. Some feed by swimming with their mouths wide open. Others open their mouths and take in huge amounts of water. When they dose their mouths, the water is forced out through the baleen, and food gets trapped in the fringe mat. After all the water is gone, the whale swallows its meal.
Toothed whales are hunters. They find, chase and then capture prey (fish, squid, crabs, starfish, and other ocean creatures) with their teeth. Once captured, the prey is swallowed whole. [Photo: sperm whale eating giant squid]
Most whales migrate to eat and breed. In general mating season occurs during the colder winter months and feeding season occurs during the warmer summer months.
In late autumn they begin an annual migratory route to their winter breeding and calving grounds in the warmer tropical waters of the Pacific. They return south in spring. Gray whales have the longest known migration of any mammal, traveling from Alaska to the coast of Mexico. This is a round-trip journey of more than 20,000 kilometers (12,000 miles).
Mating rituals can include charging at other whales, performing acrobatic feats to show off their physical youth and singing mating songs among other mating rituals used to attract a female.
Females often have many partners during the mating season so it is highly likely that she will conceive.
The gestation period in most whale species is 10 to 16 months. Generally a single young is born, tail first likely in order to prevent drowning, and twins are very rare.
The ‘baby’ stage runs from birth until the calf is weaned, during which time the calf frequently nurses on the mother’s nutrient rich milk. Baleen whales will wean their calves by their first summer when they are less than a year old, while toothed whales take up to three years to be completely weaned.
You can tell the age of a whale by counting the rings in its earwax.
A blue whale is larger than a basketball court and can weigh as much as 33 elephants.
The blue whale can produce the loudest sound of any animal. At 188 decibels, the noise can be detected over 800 kilometers (500 miles) away. A passenger jet at take off makes a noise that is 120 decibels.
Cuvier’s beaked whale is the deepest diving mammal, able to go nearly 3,000 meters (10,000 feet) down.
Unlike a fish’s tail, which is flat-sided, a whale’s tail is perpendicular to its body, like an airplane’s tail.
A whale uses its tail in an up-and-down motion to swim, whereas a fish uses a back-and-forth motion with its tail.
Baleen is made mostly of keratin, a substance found in our fingernails and hair.
The killer whale is actually not a whale. It is the largest member of the dolphin family.
Whales can suffer from sunburns.
Many expensive Perfumes contain sperm whale poop.