Have you ever wondered what the fastest animals underwater would be? Well, the answer is not a cheetah underwater.
It seems like the fastest animals on land always get the attention (looking at you, cheetah), and it’s high time that changed because some sea animals are swift indeed.
Many fish and marine mammals rely on speed to survive, whether that be through catching prey, escaping predators, or both.
The fastest swim at speeds of 70 mph (miles per hour). Humans haven’t managed to reach four mph in the water, and even our submarines top out at 50 mph.
That’s mighty impressive! Let’s look at the fastest sea animals in the ocean ranked, and see if we can uncover the mystery of how they move so marvelously. The sea animals on this list may surprise you.
Table of Contents
The Black Marlin (or Istiompax indica) is a strong, fast, and solitary open ocean fish highly prized by sports fishermen.
They are a highly migratory species found in shallow waters near the shore close to continents, islands, and coral reefs.
Their sweet spot is above the thermocline, so you’ll find them chilling in waters between 59F and 86F (15C-30C). That’s anywhere from 0ft to 3000ft (0-915 meters) depth-wise.
The longest recorded Black Marlin was 183.6 inches (4.6 meters). That’s certainly no minnow! They can weigh as much as 1,653 lbs. (750 kgs) and live between 4-12 years.
They feed on cuttlefish, squid, octopi, swordfish, and many other fish by slashing prey with their long, sharp bills.
They’re also the only marlin with non-retractable fins. It’s all starting to make sense why they evolved to become one of the fastest ocean animals.
Some people believe they are quite literally the quickest ocean animal, but reports of their speed being 82mph have mostly been exaggerated. Their maximum is more likely closer to 22mph.
Killer Whale (Orca)
The Killer Whale (or Orcinus orca) is the largest member of the dolphin family. That’s right, the dolphin family.
Killer Whales got their name from sailors who saw these massive black and white dolphins feeding on large whales. They called them “whale killers,” but the term became flipped.
Their average lifespan in the wild is 50-80 years. They grow between 23ft-32 ft (7-9.8 meters) and weigh 6 tons (5,443 kgs).
Unlike the Black Marlins, Orcas are incredibly social and travel in pods. Each pod has its own set of sounds, so the squad knows when to swim out.
Orcas prefer cold, coastal waters but can be found anywhere between the Equator and the polar regions. They feed on fish, penguins, seals, other whales, and seabirds.
They use echolocation and hunt in groups of up to 40 Orcas. Frequently they will even specialize in particular types of prey.
They’re at the top of the food chain already, so it’s not exactly fair that they’re also swift swimmers, but it is what it is. Scientists have recorded speeds of up to 34mph (54kph).
So Killer Whales aren’t whales, and Flying Fish can’t fly? Are there any more shocking truths to uncover today? Stay tuned to find out.
The Flying Fish (or Exocoetidae) are ray-finned fish with highly modified pectoral fins, unevenly forked tails, and a top lobe shorter than the bottom.
These fish prefer tropical and temperate zones, and they live off both the Atlantic and Pacific coasts of the United States.
They’re also out in the open ocean of the Indian, Atlantic, and Pacific. They feed mainly on plankton but occasionally eat small crustaceans and various other foods. They can grow up to 18 inches (45 cm) but are usually between 7-12 inches (17-30 cm).
They also max out at a whopping 2 lbs. (0.9 kgs) and have an average life span of 5 years. The especially impressive trait is their speed.
They can propel themselves out of the water at an incredible 35 mph (56kph), where their wing-like fins enable them to glide long distances.
Shortfin Mako Shark
The Shortfin Mako Shark (or Lamniformes lamnidae) is a large, predatory shark. It’s the fastest shark on the planet and one of the quickest ocean animals. It’s just as known for its incredible jumping ability and leaping crazy heights while hunting.
Makos reach 12ft (3.8 meters) and weigh at least 1,200 lbs. (545 kg). They can be found in the open ocean worldwide in tropical and temperate waters.
They’re at the top of the food chain and have no natural predators as adults, though other sharks, including adult Mako, do eat Mako Shark pups.
These sharks feed mainly on bony fish and squids but will eat other sharks, small marine mammals, and sea turtles.
They have a countercurrent exchanger adaption that gives them a considerable hunting advantage in cold water.
They also have a hunting advantage called super shark speed. They can swim as fast as 45 mph (74kph).
If you can believe it, Pilot Whales (or Globicephalinae globicephala) are the second-largest dolphin species. They got their name from the behavior of following a “pilot,” or leader when going long distances.
You can find these misleading mammals in oceans across the world. Depending on the species of Pilot Whale, they may be located anywhere from the temperate waters of the Indian Ocean to the subpolar latitudes of the North Atlantic Ocean.
They live between 45-60 years, can grow as long as 19ft (6.5 meters), and max out at 5,070 lbs. (2300 kg).
They are active predators who feed primarily on squid but will branch out and hunt large demersal fish like cod.
They can dive as deep as 1,640 ft (500 meters) and go as fast as 47 mph (76 kph). That’s only two mph more than the Shortfin Mako Shark, but it still counts. They didn’t get the nickname “Cheetahs of the Deep” for nothing.
The Atlantic Bluefin Tuna (or Thunnus thynnus) is sometimes known as the northern bluefin tuna, giant bluefin tuna, or common tunny.
It’s an aggressive predator and one of the fastest and strongest across the big ocean blue. If you look at their face, you can tell that they’re either going to fight you or drop the sickest rap album. Maybe both.
It’s the largest tuna species and weighs up to 2,000 lbs. (900 kg) and gets as long as 15 ft (4.6 meters). They can also dive as deep as 3,301 ft (1,006 meters).
These fierce fish are highly migratory but call the western and eastern Atlantic Ocean home, as well as the Mediterranean Sea.
Interestingly enough, Bluefin Tuna start as tiny larvae that aren’t longer than a few millimeters and don’t weigh more than a few hundredths of a gram. In 3-5 years, they’ll have grown to be 3 ft long (1 meter) and are much heavier.
Because they live life on both ends of the spectrum, they eat a relatively wide variety of food types throughout their lifetimes.
When they’re babies, they eat plankton. When they’re adults, they feed on bony fish like sardines, herring, mackerel, and invertebrates like squid.
Now, let’s get to the speed. The Bluefin Tuna can swim at speeds of 43 mph (69 kph), so they could technically go on the highway.
Despite what I’ve said about other animals on this list, it is entirely fair for the Bluefin to swim this fast. They face a multitude of predators throughout their lives, especially humans who overfish, so they need all the help they can get.
The Yellowfin Tuna (or Thunnus albacares) is a torpedo-shaped species of tuna often marketed as Ahi. It’s a larger tuna but not as large as the Bluefin.
It grows up to 400 lbs. (180 kg) in weight and is as long as 7’10” (2.4 meters). The average lifespan for them is 6 or 7 years.
Like the Black Marlin, Yellowfin Tuna prefer to live life above the thermocline though they can dive to depths up to 3,810 ft (1,160 meters).
They can be found in the open ocean worldwide, wherever tropical or temperate waters are. Also, like their cousins, the Bluefin, Yellowfin start as microscopic babies and then grow into their full size.
They also eat a wide variety of food, too. Their adult diet consists of other fish, crustaceans, and squid.
Thanks to their sleek torpedo bodies, they can swim fast enough to hunt baitfish like the flying fish, sauries, and mackerel. They pretty much sit at the top of the food chain.
Large and fast species like toothed whales, pelagic sharks, and Marlins hunt Yellowfin Tuna, so their swiftness is an asset.
They can easily evade most predators, thanks to being warm-blooded. Their already-warm muscles are the key to being strong, fast swimmers.
These guys can get up to 50 mph (80 kph), and they need to escape their problems. They also are heavily fished for commercial use.
Marlin (Istiophoridae istiophorus) is a family of about ten different species, including the already mentioned Black Marlin.
They have long bodies and sometimes even longer spear-like bills. Their name most likely comes from this resemblance to a sailor’s marlinspike.
The larger species, the Atlantic Blue Marlin, can grow as large as 14 ft (4.3 meters) and weigh as much as 1985 lbs. (900 kg).
They have an average lifespan of up to 18 years for males and 27 years for females. Blue Marlin dwell throughout the tropical and subtropical waters of the Atlantic, Indian, and Pacific Oceans.
They’re migratory fish and will follow the warm water for hundreds, if not thousands, of miles.
They like to feed on mackerel and tuna near the surface but will also dive deep to eat squid. Blue Marlin use the spear on their face to divebomb dense schools of fish.
They swim incredibly fast, earning a place on this list. They allegedly can swim as fast as 68 mph (110 kph) in short bursts.
Swordfish (Xiphias gladius) is another long fish with a long bill. Unlike the Marlin, its sword-like bill is flat instead of rounded and is used to slash instead of spear prey.
It’s found in warm and temperate oceans worldwide. You can usually find it near the surface, basking and airing out their dorsal fins.
They also breach (jump out of the water) to dislodge pests or parasites from their skin. They feed on a wide range of pelagic fish like mackerels and barracuda, as well as demersal fish, squid, and crustaceans.
They’ll draw the sword on larger prey and eat smaller prey completely whole. Predatory fish can eat the babies, but the adults don’t have many natural predators (humans don’t count as natural).
Other large marine mammals like Killer Whales and Makos will take a whack at the Swordfish. Swordfish commonly reach 10 ft (3 meters), but the largest recorded so far is 14’11” (4.55 meters).
They can weigh up to 1,430 lbs. (650 kg) and usually live nine years. They have allegedly been quoted at speeds of 60 mph (100 kph).
Finally, we’ve arrived at the fastest fish in the ocean! The Sailfish (Istiophorus platypterus) can sail right by you at 68 mph (110 kph).
That is almost as fast as a cheetah runs on dry land. It’s incredible that any animal underwater can reach these speeds.
There are two main subspecies of sailfish: Atlantic and Indo-Pacific. They get their name from the dorsal fin that nearly spans the length of their bodies.
They like to inhabit warm and temperate waters across the world. The average lifespan is only four years, so they quickly grow to adult size.
They usually grow to around 10 ft (3 meters) long and between 120 and 220 pounds (54-100 kg) heavy.
They feed on small fish like anchovies and sardines, as well as squid and octopus. They can use their sails to shepherd smaller fish into easy pickings.
They often hunt in groups and benefit from another member’s unsuccessful attempts. The longer an attack, the more injured fish are in a school. It’s pretty efficient.
BONUS FAQ: What Makes Fish Swim So Quickly
Did you know that physicists have argued for 50 years over which theory explains how fish produce thrust? All fish have to compromise between drag and thrust to achieve efficient movement underwater, and up until recently, they couldn’t agree on how that was possible.
When fish are living their everyday fish lives and doing their regular swimming styles, their muscles will contract in a sequence going from the head towards the tail.
This swimming pattern produces a backward-moving wave that pushes against the water and generates thrust and drag.
There were two main theories about how this happens: resistive thrust theory and elongated body theory. The resistive thrust produces a resistive force that acts in the opposite direction of the body and has to do with velocity.
The elongated body produces a reactive power that operates in the opposite direction of the force of action and has to do with acceleration.
The difference, a subtle but important one, was between the type of force generated. Why does it even matter? Understanding how it works is necessary to reproduce it artificially.
It turns out that both theories are correct, but for different kinds of fish with different body shapes. Sometimes it’s even different for other parts of the fish bodies!
It’s so nice when everyone can be right at the same time. Elasticity plays an essential role in this swimming business, too.
The thought is that elasticity helps the fish store up energy and improve swimming efficiency though no one has been able to measure this while fish are swimming. It’s also thought that the elastic energy transfers across fish bodies through long tendons.
The whole thing is pretty complex and thus difficult to replicate artificially. It’s more complicated than initially thought, though that won’t stop us from trying.