Dolphins are popular marine animals known for their playful water antics and intelligence. There are about 40 species of dolphins that belong to the order Cetacea, translated as “large sea creature”.
They are characterized as having a streamlined body about 10 feet in length. Dolphins have a horizontal tail fin, a rounded hooked or curved dorsal fin, no hind limbs, and a respiratory blowhole. They have elongated “beaks” with cone-shaped teeth.
Dolphins are carnivorous predators that eat crustaceans, fish, squid, and bottom-dwelling invertebrates.
Different species of dolphins live in freshwater or salt water from the equator to subpolar waters and river systems. They spend time in social groups (pods) anywhere from 5 to thousands.
Dolphins are typically gray or black on top with shading to a lighter gray, although the Amazon river dolphin is pink. They have a lighter or white underbelly. This coloring allows them to camouflage with the water from above and the surface light from underneath.
Dolphins produce underwater whistles, clicks, and other ultrasonic sounds for communication and echolocation.
Read on to learn about the 17 animals that are similar to dolphins, and you may find a few surprises below!
Scientific Name: Phocoenidae
Quick Summary: Porpoises look very much like dolphins at a broad glance, living in similar areas, and eating similar diets.
Porpoises are often mistakenly called dolphins, but in fact, they are different species.
There are only 7 species of porpoises, and they belong to the Phocoenidae family. Dolphins belong to different families depending upon their species. These include Delphinidae, Platanistidae, and Iniidae.
A porpoise’s spade-shaped teeth, smaller mouth, triangular dorsal fin, and stocky body are different from the dolphin’s.
However, these differences are slight and at a quick glance to the untrained eye, porpoises look like dolphins.
However, they are both intelligent, with complex brains. They both use echolocation to navigate the waters, eat a carnivorous diet, and live in either freshwater or marine waters.
Scientific Name: Coryphaena hippurus
Quick Summary: This creature is a fish, but like a dolphin has a long body, dorsal fin, and white underbelly.
The dolphinfish is also called mahi-mahi and is not related to the dolphin, despite its name.
Its name is given to it for its similarly long dolphin-like body. This fish has a forked, vertical caudal tail, and a dorsal fin that runs the length of its body.
Its body is primarily a metallic blue-green but its light and white underbelly are like a dolphin’s. These fish grow to lengths of 3 to 6 feet.
Interestingly, these fish can cause illness in humans when consumed. This is from a high concentration of ciguatoxins from marine dinoflagellates.
Regardless, dolphinfish are frequently harvested from tropical and subtropical waters. They are considered a good source of food because they grow fast and have high reproductive rates.
3. Elephant-Nose Fish
Scientific Name: Gnathonemus petersii
Quick Summary: This tiny fish has a long nose that makes it look much like the head shape of a dolphin.
The elephant-nose fish is an unusual-looking fish that resembles a miniature dolphin with its long “beak”. However, this protrusion is part of the fish’s mouth for communication and defense.
They live in murky and muddy freshwater rivers, feeding on worms and insects. The dorsal fins are near the ends of their bodies, instead of in the middle like dolphins.
This unique 9-inch fish has an organ on their forked vertical tails to create electrical fields to find mates and sources of food.
Scientific Name: Istiophoridae
Quick Summary: The marlin is shaped similarly to the dolphin with a long face and body, that is dark on the top and white underneath.
Marlins live in marine waters eating a carnivorous diet of primarily tuna and other fish found in open waters.
They have an elongated body with a lethal-spear-shaped upper bill. A long, rigid dorsal fin forms a crest near the head. Marlins have a darker cobalt-blue upperside and silvery-white underside.
Marlins are known for their super speed in the water, capable of reaching speeds over 65 miles per hour.
Scientific Name: Monodon monoceros
Quick Summary: Narwhals resemble dolphins with their blue-gray color, horizontal tail fin, and blowhole.
Narwhals are similar in size and coloration to dolphins, but with a stockier build. They are blue-gray, blue-black, or mottled gray. Elderly narwhals are nearly all white.
They use a blowhole for respiration and will die if trapped underneath ice.
Living in Arctic waters, the narwhal uses its single-pointed tusk to hit and stun fish before consuming them. They do not have teeth or dorsal fins, however, they have a horizontal dorsal tail like dolphins.
Scientific Name: Selachimorpha
Quick Summary: Shark fins protrude from the water, looking very similar to a dolphin’s, but a closer look reveals their fins are squared off and triangular.
Sharks are often confused with dolphins when their dorsal fins are spotted poking out of marine waters.
However, a closer look will reveal which creature is there. Shark fins are triangular, and the back edge that points back is squared off or flat.
Sharks are fish, whereas dolphins are mammals, meaning their tail fins are different. Sharks have vertical tail fins and dolphins’ are horizontal ones.
Sharks do not come to the surface to breathe, since they use gills (and not a blowhole) for respiration.
Often sharks are solitary swimmers moving in one direction. This is different from dolphins which tend to travel together in pods and swim in an up-and-down motion.
7. Pygmy Sperm Whale
Scientific Name: Kogia breviceps
Quick Summary: Pygmy sperm whales are similar in size, shape, and diet to dolphins and also use echolocation.
Pygmy sperm whales are similar in size and shape to dolphins, around 10 feet in length, with elongated bodies.
They are found sharing waters with dolphins in the Pacific, Atlantic, and Indian oceans. They also eat a carnivorous diet of octopus, shrimp, and squid.
They use echolocation to find prey and communicate with clicks, using the fat on their heads to modulate sounds.
These whales do not have enamel on their teeth. They also have fewer brain neurons than dolphins, making them less social. They are easily frightened and expel a red fluid to confuse predators.
8. Beaked Whale
Scientific Name: Hyperoodontidae
Quick Summary: Beaked whales and dolphins have similar bottlenose-shaped snouts.
Beaked whales have a bottlenose-shaped “beak” much like dolphins. However, they have a distinctive bulging forehead that makes them noticeably different.
They live in deep waters of the North and South poles, diving nearly 10,000 feet deep, and eating prey such as squid and fish at all levels of the sea.
Beaked whales have few or no teeth, and eat by suction feeding. They expand their throats and move their tongues back to create a pressure change that pulls in the prey.
9. Pilot Whale
Scientific Name: Globicephala
Quick Summary: Pilot whales are in the dolphin family, with unique features such as sickle-shaped flippers and a heart-shaped patch on the underbelly.
Despite its name, the pilot whale is a dolphin. They are large members of the Delphinidae family, about 13 to 20 feet long.
They appear black or dark coal-gray, in color, with a white heart-shaped patch on their underbelly.
They have sickle-shaped flippers and a rounded, curved dorsal fin. Different species are found in either tropical or colder oceanic waters.
10. Orca Whale
Scientific Name: Orcinus orca
Quick Summary: Orca whales are in the dolphin family, despite their name and size.
Also, called the killer whale, orca whales are actually in the dolphin family, and are often mistaken as a whale. They belong to the order Cetacea, suborder Odontoceti, family Delphinidae, and genus Orcinus.
Despite their unique black and white color coloring, they are similar in shape, diet, and range to other dolphins. They are the largest of the dolphin family, reaching lengths over 33 feet, with a 6-foot-tall dorsal fin.
These were given the “killer” nickname after sailors from long ago witnessed them preying on large whales. They also eat fish, seals, sea lions, porpoises, rays, sharks, other dolphins, seabirds, and so on.
11. Beluga Whale
Scientific Name: Delphinapterus leucas
Quick Summary: Beluga whales are social animals, found interacting with dolphins.
Beluga whales are social animals like dolphins, and they can be found playing or interacting with each other. Also like dolphins, they produce clicks and whistles for communication.
Belugas are slightly longer than dolphins. They can swim backward and due to un-fused neck vertebrae can turn their heads upside down and side to side.
Their melon-shaped heads are flexible, and they can make facial expressions that often make them look happy.
They do not have dorsal fins, which allow them to swim underneath the ice in arctic waters. They can dive about 2,000 feet deep to eat food such as fish, crabs, octopuses, squid, and sandworms.
12. Harp Seal
Scientific Name: Pagophilus groenlandicus
Quick Summary: Harp seals are agile swimmers with flipper-like tails that make them look like small dolphins in the water.
In the water, a harp seal might trick someone into thinking a dolphin is nearby. Its flipper tail and agile swimming help them move through the water with grace like a dolphin.
They can dive up to 1,000 feet deep, searching for food such as fish and crustaceans, and stay submerged for up to 15 minutes,
Harp seals share some of the same waters as dolphins during migration. However, they tend to stick to colder areas of the North Atlantic and Arctic oceans.
They also can come up on land or ice for breeding and birthing offspring.
Scientific Name: Trichechus
Quick Summary: Manatees are like dolphins in that they live in marine and freshwater habitats, are mammals, and have live offspring.
Similar to dolphins, manatees live in marine and freshwater habitats. They have agile flippers that allow them to scoop up plants for their herbivore diet. Their tail is paddle-shaped, much different than a dolphin’s.
They are slightly longer than dolphins at 13 feet but much stockier. Manatees breathe through nostrils instead of a blowhole.
Dolphins and manatees alike are mammals that birth live offspring and produce milk to feed their young. Manatees lose and replace their teeth, whereas dolphins retain one set for their entire life.
Scientific Name: Dugong dugon
Quick Summary: Dugongs are similar in length, nurse their young, and have a tail fluke shaped like a dolphin’s.
The dugong is related to manatees. However, it is restricted to coastal habitats in the Indian and Pacific oceans, which have an ample supply of seagrasses.
They are similar in length to dolphins ranging from 8 to 13 feet long. They actively raise their young like dolphins, nursing them for about a year.
They have a horizontal tail fluke shaped like a dolphin’s tail, yet they also have 2 tusks for foraging that grow as they age.
Dugongs are often the prey of orca whales and sharks.
15. Blue Whale
Scientific Name: Balaenoptera musculus
Quick Summary: Despite their large size, blue whales are like dolphins with their blue-gray coloring and long sleek bodies.
Blue whales are long and slender, reaching lengths from 70 to over 100 feet, and weighing over 300,000 pounds. Their blue-gray bodies blend in with the water, and they are found in oceanic water except for the Arctic.
Unlike dolphins, they do not have teeth. Instead, they have baleen plates that strain water to consume large amounts of krill. Krill are only a few centimeters big, and blue whales eat up to 6 tons of them daily.
16. Manta Ray
Scientific Name: Manta
Quick Summary: Manta rays are like dolphins in that they are both intelligent and can leap out of the water.
Manta rays are very different in appearance from dolphins. They have diamond-shaped bodies, wig-like fins, and gills.
However, they are intelligent like dolphins. For example, they have demonstrated that they can recognize themselves in mirrors. This indicates a high cognitive function.
Manta rays are fish, not mammals, and have the largest body-to-brain ratio as compared to other fish.
Scientific Name: Hippopotamus amphibius
Quick Summary: Hippopotamus and dolphins share a common ancestor, birth and nurse offspring underwater, and have similar aquatic skin.
Cetaceans, which include dolphins, share a common ancient ancestor with the hippopotamus. They both have skin that is developed for aquatic life.
They also share mammalian characteristics that other mammals do not have, even though they look different. Both give birth and nurse their offspring underwater.
They lack scrotal testes and do not have sebaceous glands (to produce oil at hair follicles).
Many animals are somewhat similar to dolphins, including some living on land, such as the harp seal and the hippopotamus. Manta rays are similar to dolphins in that they are intelligent creatures that can leap out of the water.
Porpoises, dolphinfish, and beaked whales are marine animals similar to dolphins. They are similar in size or have features such as a bottle-shaped nose, horizontal tail fin, or pointed head like the dolphin.
Many of the above animals are found in marine waters like dolphins, often swimming in the same locations and similar diets.