Toothed whales are a fascinating group of marine mammals that have captured the imaginations of scientists and novelists alike. They are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales.
There are approximately 73 species of toothed whales described, and they are one of two living groups of cetaceans, the other being the baleen whales.
Toothed whales have a variety of teeth adapted to suit their unique hunting habits, and they use their teeth to capture and devour prey, including fish, squid, and other marine animals. The number, size, and shape of teeth vary depending on the species and their diet.
In this article, we will explore the different types of toothed whales, including their unique characteristics and behaviors.
9 Types Of Toothed Whales
Beluga Whale and Narwhal
Beluga whales and narwhals are two species of toothed whales that belong to the Monodontidae family. They are the only two living species in this family, and both are native to coastal regions and pack ice around the Arctic Ocean.
Beluga whales and narwhals are relatively small whales, between three and five meters in length, with a forehead melon and a short or absent snout. They do not have a true dorsal fin, but they do have a narrow ridge running along the back, which is much more pronounced in the narwhal.
Both species are highly vocal animals, communicating with a wide range of sounds, and they also use echolocation to navigate. Beluga whales can be found in the far north of the Atlantic and Pacific Oceans, while the distribution of narwhals is restricted to the Arctic and Atlantic Oceans.
Monodontids have a wide-ranging carnivorous diet, feeding on fish, mollusks, and small crustaceans. They have reduced teeth, with the beluga having numerous simple teeth, and the narwhal having only two teeth, one of which forms the tusks in males.
Gestation lasts 14–15 months in both species, and almost always results in a single calf. The young are not weaned for a full two years, and do not reach sexual maturity until they are five to eight years of age.
Recently, scientists have been tracking a pod of beluga whales that seems to have adopted a lone male narwhal in Canada’s St. Lawrence River, and they are watching to see if the lone male will mate with one of its beluga peers to produce a hybrid known as a “narluga”.
Sperm whales are the largest of the toothed whales and are easily recognizable by their enormous square head and narrow lower jaw. They are dark blue-gray or brownish, with white patches on the belly, and are thickset with small paddle-like flippers and a series of rounded humps on their back.
Males can reach a maximum length of about 24 meters and weigh up to 50 metric tons, while females are smaller, usually measuring less than about 14 meters and weighing less than 25 metric tons.
Sperm whales are deep divers, commonly reaching a depth of about 350 meters, and have been found tangled in cables more than 1,000 meters below the surface. They are known for their large conical teeth, which they use to ensnare their preferred prey, and they have the most powerful sonar of any animal, which they use to find their prey in the dark deep sea.
Sperm whales are found in temperate and tropical waters throughout the world, usually in pods of about 15 to 20, although solitary males may wander into colder regions. They feed primarily on cephalopods, including the giant squid, and can eat up to one ton of food per day.
Sperm whales have a polygynous mating system, which means that one male mates with multiple females, and they form breeding schools consisting of 1-5 big males and a group of males and females of various ages. Gestation lasts for 14-16 months, and one calf is born at a time.
Beaked whales are a family of cetaceans that are known for being one of the least-known groups of mammals due to their deep-sea habitat, reclusive behavior, and apparent low abundance. There are 24 existing species of beaked whales, and only three or four of them are reasonably well-known.
Beaked whales are moderate in size, ranging from 4.0 to 13 meters and weighing from 1.0 to 15 tonnes. Their key distinguishing feature is the presence of a ‘beak’, somewhat similar to many dolphins. Other distinctive features include a pair of converging grooves under the throat, and the absence of a notch in the tail fluke.
Beaked whales are deep divers with extreme dive profiles, regularly diving deeper than 500 meters to echolocate for food, and these deep dives are often followed by multiple shallower dives less than 500 meters.
They are known to congregate in deep waters off the edge of continental shelves, and bottom features, such as seamounts, canyons, escarpments, and oceanic islands.
Here are some of the species of beaked whales:
– Baird’s Beaked Whale: This is the largest member of the beaked whale family, and they can be found throughout the North Pacific Ocean and adjacent seas and in U.S. waters off the West Coast from California to Alaska. They have a large, slender, long, robust body with a relatively small, rounded, triangular dorsal fin that is located about two-thirds of the way down their back.
– Cuvier’s Beaked Whale: This is one of the most frequently sighted species of beaked whales in the world, and they are found in most oceans and seas worldwide. They have a small, inconspicuous blow at the water’s surface, making them challenging to observe and identify to the species level.
– Northern Bottlenose Whale: This species was extensively hunted in the northern part of the North Atlantic in the late 19th and early 20th centuries.
– Sowerby’s Beaked Whale: This species is found in the North Atlantic and is known for its distinctive beak and small size.
– Longman’s Beaked Whale: This species is found in the Indian and Pacific Oceans and is known for its long, slender body and small head.
These are just a few examples of the many species of beaked whales that exist.
Dolphins and Porpoises
Dolphins and porpoises are marine mammals that belong to the order Cetacea, which also includes whales. Although people often use the terms dolphins, porpoises, and whales interchangeably, there are differences between them.
Dolphins are more prevalent than porpoises, with 32 species of dolphins (plus five closely related species of river dolphin) and only six species of porpoises. Dolphins tend to have prominent, elongated “beaks” and cone-shaped teeth, while porpoises have smaller mouths and spade-shaped teeth.
Dolphins also have a hooked or curved dorsal fin, while porpoises have a triangular dorsal fin. Generally speaking, dolphin bodies are leaner, and porpoises’ are portly. Dolphins are also more talkative than porpoises, making whistling sounds through their blowholes to communicate with one another underwater.
Both dolphins and porpoises are air-breathing, warm-blooded mammals that nurse their young. They are highly social and live in groups, and they exhibit complex methods of communication and echolocation making squeaks, buzzes, whistles, and clicks that can be heard from miles away.
Dolphins and porpoises are at the top of the food chain and play an important role in the overall balance of the marine environment. They are protected under the Marine Mammal Protection Act, and some are also listed under the Endangered Species Act.
Pygmy Sperm Whale and Dwarf Sperm Whale
Pygmy sperm whales and dwarf sperm whales are two species of toothed whales that belong to the Kogiidae family. They are not often sighted at sea, and most of what is known about them comes from the examination of stranded specimens.
Pygmy sperm whales are not much larger than many dolphins, growing to about 3.5 m (11 ft) at maturity, while dwarf sperm whales can range in size from 2 to 2.7 m (6.6 to 8.9 ft) in length.
Both species have a shark-like head that is large in comparison to body size, given an almost swollen appearance when viewed from the side. Like their giant relative, the sperm whale, both species have a spermaceti organ in their forehead, which helps them focus sound.
They also have a sac in their intestines that contains a dark red fluid, which they may expel when frightened, perhaps to confuse and disorient predators.
Pygmy sperm whales and dwarf sperm whales possess the shortest rostrum of current-day cetaceans, with a skull that is greatly asymmetrical. Both species are unique among cetaceans in using a form of “ink” to evade predation in a manner similar to squid. Pygmy sperm whales and dwarf sperm whales are found in temperate and tropical seas worldwide, and they are considered rare.
River dolphins are a group of fully aquatic mammals that reside exclusively in freshwater or brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea.
Extant river dolphins are placed in two superfamilies, Platanistoidea and Inioidea, and they comprise the families Platanistidae (the South Asian dolphins), the recently extinct Lipotidae (Yangtze river dolphin), Iniidae (the Amazonian dolphins), and Pontoporiidae. River dolphins are related to the Indohyus, an extinct chevrotain-like ungulate, from which they split approximately 48 million years ago.
The primitive cetaceans, or archaeocetes, first took to the sea approximately 49 million years ago and became fully aquatic by 5–10 million years later.
River dolphins are found in rivers of south-central Asia, China, and South America and in the coastal waters of Brazil, Argentina, and Uruguay. Here are some of the species of river dolphins:
– Ganges River Dolphin: This species can only live in freshwater and is essentially blind. They hunt by emitting ultrasonic sounds, which bounces off of fish and other prey, enabling them to “see” an image in their mind. They are frequently found alone or in small groups, and generally, a mother and calf travel together. Calves are chocolate brown at birth and then have grey-brown smooth, hairless skin as adults. Females are larger than males and give birth once every two to three years to only one calf.
– Amazon River Dolphin: This species is also known as the pink river dolphin, and it is the largest of the river dolphins. They are found in the Amazon and Orinoco river systems in South America. They are known for their distinctive pink coloration, which is more prominent in males than females. They are also known for their long, slender snouts, which they use to catch fish and other prey. Amazon river dolphins are threatened by habitat loss, pollution, and hunting.
– Indus River Dolphin: This species is found in the Indus River in Pakistan. They are one of the rarest mammals in the world, with only about 1,500 individuals remaining. They are blind and use echolocation to navigate and find prey. They are threatened by habitat loss, pollution, and accidental entanglement in fishing nets.
These are just a few examples of the many species of river dolphins that exist.
Pilot whales are a group of toothed whales that belong to the genus Globicephala. There are two extant species of pilot whales: the long-finned pilot whale (G. melas) and the short-finned pilot whale (G. macrorhynchus).
The two species are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between them. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters.
Pilot whales are known for their social behavior and are often found in large groups called pods. They are notorious for stranding themselves on beaches, but the reason behind this is not fully understood, although marine biologists have shed light on the discovery that it is due to the mammals’ inner ear (their principal navigational sonar) being damaged from noise-pollution in the ocean, such as from cargo ships or military exercises.
The conservation status of short-finned and long-finned pilot whales has been determined to be least concern. Here are some key facts about pilot whales:
– Pilot whales are medium-sized toothed whales that have a stocky, sturdy body.
– They have a large bulbous or squarish forehead, known as a melon, and a short beaklike snout.
– The dorsal fin of pilot whales is far forward on their body and has a relatively long base.
– Both species of pilot whales are black, and some individuals have a pale elongated anchor-shaped mark adorning the throat and chest.
– Pilot whales are found in all the oceans of the world except the Arctic, but long-finned pilot whales are not found in tropical waters.
– Males of both species are larger than females, and the average life span for males of both species is 46 years.
– Pilot whales have been kept in oceanariums, where they are sometimes trained to perform, and the U.S. Navy has attempted to train pilot whales to attach devices to stray torpedoes.
– In some areas, pilot whales are still hunted for meat and oil, and in the Faroe Islands, they are captured by first frightening the whales by making noise in the water and then driving them ashore to be killed.
Overall, pilot whales are fascinating and social animals that are found in many of the world’s oceans.
Risso’s dolphin (Grampus griseus) is a species of dolphin and the only member of the genus Grampus. Risso’s dolphin is named after Antoine Risso, whose study of the animal formed the basis of the recognized description by Georges Cuvier in 1812. They are found in temperate and tropical waters worldwide, preferring deeper water and are usually found on the edge of continental shelves.
Risso’s dolphins have a robust body with a narrow tailstock, and they can reach lengths of approximately 8.5 to 13 feet and weigh 660 to 1,100 pounds. They have a relatively large anterior body and dorsal fin, while the posterior tapers to a relatively narrow tail. The bulbous shape of the head has a vertical crease in front.
Risso’s dolphins are typically found in groups of between 10 and 30 animals, though they have been reported as solitary individuals, in pairs, or in loose aggregations in the hundreds or thousands.
Occasionally, this species associates with other dolphins and whales, such as bottlenose dolphins, false killer whales, pygmy killer whales, melon-headed whales, long-finned pilot whales, and short-finned pilot whales. Risso’s dolphins are protected in the United States under the Marine Mammal Protection Act of 1992.
Orca (Killer Whale)
Orcas, also known as killer whales, are the largest member of the dolphin family and one of the world’s most powerful predators. They are immediately recognizable by their distinctive black-and-white coloring.
Orcas are found in all of the world’s oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas. They are at the top of the food chain and have very diverse diets, feasting on fish, penguins, and marine mammals such as seals, sea lions, and even whales, employing teeth that can be four inches long.
Orcas are highly intelligent, social mammals that have long been a part of marine park entertainment, performing shows for audiences. However, it has become increasingly clear that orcas do not thrive in captivity. To catch their prey, pods of orcas will engage in intricate and coordinated hunting maneuvers, forcing a group of fish to the water’s surface.
Orcas are highly distinctive and easily recognizable, and although still considered a single species, there are at least eight different recognized forms, differing in external coloring and appearance, feeding habits, and ecology.
Two unnamed subspecies are recognized off the West Coast of North America – mammal-eating ‘transient’ and fish-eating ‘resident’ killer whales. Orcas are native to many countries and territories worldwide.
1. What are toothed whales?
Toothed whales are a suborder of cetaceans that have teeth instead of baleen plates in their mouths. They include dolphins, porpoises, and sperm whales, among others.
2. How do toothed whales differ from baleen whales?
Baleen whales have baleen plates and filter small creatures like krill from the water, while toothed whales have teeth and feed on fish and squid.
3. How many species of toothed whales are there?
There are over 70 species of toothed whales, including some of the largest and most intelligent animals on Earth.
4. What are some examples of toothed whales?
Some examples of toothed whales include the sperm whale, killer whale, beluga whale, narwhal, and beaked whales.
5. What is the difference between dolphins and porpoises?
Dolphins tend to have prominent, elongated “beaks” and cone-shaped teeth, while porpoises have smaller mouths and spade-shaped teeth. Dolphins also have a hooked or curved dorsal fin, while porpoises have a triangular dorsal fin.
6. Where are toothed whales found?
Toothed whales are found in all of the world’s oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas.
7. What is the conservation status of toothed whales?
Many species of toothed whales are threatened by human activities such as overfishing, pollution, and habitat destruction, and conservation efforts are needed to ensure their survival.
8. What is the role of toothed whales in the marine ecosystem?
Toothed whales are an important part of the marine ecosystem and play a vital role in maintaining the balance of the ocean’s food chain. They are at the top of the food chain and have very diverse diets, feasting on fish, penguins, and marine mammals such as seals, sea lions, and even whales.