As we become more connected to the world with technology, humans have subsequently become more fascinated with nature and its inhabitants. Specifically, the sea and which fish live beneath its surface. For one, the biggest saltwater fish isn’t going to answer itself.
What swims in our oceans? How big can they get? What do they look like?
We often see posts on social media of someone swimming a massive fish and we can’t help but wonder what it is and how it compares to other saltwater fish out there.
You’ve likely come across lists that feature sharks and whales, but today we take a deeper look into just the biggest FISH that swim in our beautiful oceans around the world.
So, without further ado, let’s take a look at the 13 biggest saltwater fish and their pictures, starting with…
Number 13 – Sailfish
- Average weight – 200 lbs (90.7 kg)
- Average length – 10 ft (3 m)
The first species on our list is the distinctively-featured sailfish. These fish are easily identified by their large dorsal fins, sail on their back and long, pointy bills.
Sailfish are one of the fastest fish in the ocean, reaching speeds of up to 68 mph! They’re also excellent jumpers and have been known to leap out of the water as high as 20 feet.
They’re named for their massive sails, which they use to herd fish into groups before attacking.
These predators primarily feast on smaller fish like sardines and squid, but have also been known to take down larger prey like smaller tuna and mackerel.
Number 12 – Yellowfin Tuna
- Average weight – 200 lbs (90.7 kg)
- Average length – 5 ft (1.5 m)
What an absolutely beautiful fish this is. It’s one of our favorite species in the ocean thanks to its electric colors and spectacular sickles.
The yellowfin tuna can grow much larger than its average size, with some of the bigger specimens weighing up to 400lbs. Their streamline fins and a sleek body allows them to go as fast as 50mph. They school together in the hundreds and often cause mayhem on the surface of the water as they feast on smaller fish.
Their colors can range from a deep blue to bright silver, with yellowish stripes running along their sides.
These predators are found in tropical waters around the world and their expected lifespan ranges from 20-30 years.
Number 11 – Oarfish
- Average weight – 220 lbs (99.8kg)
- Average length – 12 ft (3.7m)
Now here’s a fascinating fish that you might not of heard of! The oarfish is the world’s longest bony fish and can grow up to an impressive 36 feet in length.
Despite their size, oarfish are relatively lightweight as they have very little body fat. They’re silver in color with long, red fins and a streamer that runs the entire length of their body.
Oarfish are built for the deep dark depths of the ocean, as they’re able to withstand extreme pressure and lack of light. They live at depths of up to 3000 feet and are rarely seen by humans.
They were first described in 1772 and there’d be few sightings until a team of US Navy Seals came across a dead specimen in a 1996 training session.
Number 10 – Big Eye Tuna
- Average weight – 250 lbs (113.4kg)
- Average length – 6 ft (1.8m)
The name says it all, right? These tuna have eyes that are significantly larger in proportion to their head size than any other fish in the tuna family.
The big eye tuna is also built for speed, with a long pectoral fin and streamlined body that helps them reach speeds of up to 50 mph. Their colors can range from a deep blue to bright silver, with yellowish stripes running along their sides.
They’re found in tropical waters around the globe and typically live between 20-30 years.
Number 9 – Goliath Grouper
- Average weight – 400 lbs (181.4 kg)
- Average length – 8 ft (2.4 m)
If David were a regular fish of the reef, we’re sorry to say that it probably wouldn’t stand a chance against this beast of the depths. Goliath in name and in nature, this grouper is one of the biggest fish in the sea.
Goliath groupers are brown or olive green in color, with small white spots dotting their body. They have a large mouth and an even larger appetite. These fish can grow up to eight feet long and weigh as much as 800lbs!
They’re found in shallow coastal waters around the world, often near reefs or shipwrecks. These curious creatures are not afraid of humans and have even been known to keenly approach divers!
If you do happen to come across a Goliath whilst diving, be sure not to startle it as they have been known to attack humans when startled or provoked.
Number 8 – Swordfish (Broadbill)
- Average weight – 400 lbs (181.4 kg)
- Average length – 10 ft (3 m)
Another mysterious and still relatively unknown creature of the depths is the swordfish or broadbill (sometimes broadbill swordfish).
With a thick, crescent like tail similar to a mako shark and a bill for the ages, the swordfish is an ultimate predator in the dark during the day before swimming further up the water column at night.
The swordfish is a solitary creature, coming together only to mate. They tend to have a lifespan around the 15 year mark and are found in most world’s major oceans.
Their bodies are long and sleek, allowing them to reach speeds of up to 80mph. But their most impressive feature is definitely their bill, which can be as long as 40% of its total body length! Sheesh!
Number 7 – Black Marlin
- Average weight – 500 lbs (226.8 kg)
- Average length – 9 ft (2.7 m)
The second-largest of the marlin family and third-largest billfish, black marlin are some of the most revered fish thanks to their popularity in the fishing community.
These guys are big, fast and aggressive. They can grow up to 15 feet long and weigh as much as 1500lbs. But don’t let their size fool you, black marlin are incredibly agile predators. Their long, sleek body and large tail fin allow them to reach speeds of up to 80mph!
Their colors are pretty distinctive, with a dark blue or black body and bright yellow fins. They’re found in tropical waters around the world and their lifespan is relatively unknown but believed to be around 11 years for females and 5-6 year for males.
They make annual migrations of over 5000 miles and have been known to dive as deep as 2300 feet. Some of the biggest marlin are found off the coast of Australia, so be sure to keep your eyes peeled when you make the trip to the Great Barrier Reef down-under!
Number 6 – Bluefin Tuna
- Average weight – 525 lbs (238.1 kg)
- Average length – 6.6 ft (2 m)
The top-dog of the tuna world is the bluefin. These massive fish can grow up to 12 feet long and weigh as much as 1300lbs! Like the yellowfin, they’re know the wreak havoc on the surface of the water as they school together and feast on smaller fish.
Their colors are pretty similar to their close relative the yellowfin tuna, with a dark blue body and silver sides. The main difference is that bluefin have much darker fins.
They’re found in all of the world’s oceans but tend to stick to cooler waters. They’re one of the rarer fish on this list with a population that is slowly declining.
Their primary diet is other fish but they’re not above eating the occasional squid or crustacean. They have an expected lifespan of around 40 years but are often caught before they reach maturity.
Number 5 – Sawfish
- Average weight – 700 lbs (317.5 kg)
- Average length – 8.5 ft (2.6 m)
The sawfish is a fascinating creature. It’s technically a ray but it has the long, flat body of a shark. And instead of fins, it has wing-like pectoral fins. Yes we said we’d only include fish, but you know what? This was too cool to leave off our list and it has fish in its name!
But the most distinctive feature of the sawfish is its long, toothy snout that resembles a saw. This “saw” is actually made up of long, sharp teeth that the sawfish uses to slash at its prey. And believe it or not, their diet consists mostly of small fish!
They’re found in shallow waters around the world and can grow up to 18 feet long. Sadly, their population has declined dramatically due to overfishing and habitat loss. In some parts of the world, they are considered critically endangered.
But there is some good news! In recent years, sawfish have been gaining some much needed protection.
Number 4 – Blue Marlin
- Average weight – 770 lbs (349.3 kg)
- Average length – 11 ft (3.4 m)
Time for some love of big blue! The apex of the marlin family, blue marlin are one of the most serious saltwater specimens. They’ll reach lengths of up to 15 feet and weigh as much as 1500lbs.
Blue marlin are formidable, agile predators. Their long, slender form and enormous tail fin allow them to reach speeds of up to 80 miles per hour.
As their name suggests, blue marlin are mostly blue. Their backs are a deep, inky blue while their sides are lighter, with a silver or white hue. They have long dorsal and pectoral fins that are dark in color, often with a light edge.
These fish roam the waters of the Atlantic, Pacific and Indian Oceans. Like other marlin, they’re migratory creatures, travelling long distances each year.
When it comes to hunting, blue marlin are patient predators. They’ll often swim slowly beneath their prey, waiting for the perfect moment to strike.
Number 3 – Ocean Sunfish
- Average weight – 2,200 lbs (997.9 kg)
- Average length – 10 ft (3 m)
Time for the first of the 3 of our sunfish friends! Starting with the passive ocean sunfish. Don’t let its size fool you, this fish is gentle as can be. It’s often seen basking in the sun near the surface of the water, which is how it got its name.
It’s not a speedy swimmer, but its size is what makes it noticeable close to the ocean’s surface. It can reach lengths of up to 14 feet and can weigh well over 3000lbs.
The ocean sunfish is a strange looking creature. It’s got a small mouth and a large, flat body. Its dorsal and anal fins are long and thin, while its tail fin is stubby and short.
Despite its slow and gentle nature, the ocean sunfish has very few predators. Sharks and orcas will sometimes eat them, but their size often protects them from becoming prey. Amazing what size can do in the animal kingdom, right?
Number 2 – Hoodwinker Sunfish
- Average weight – 4000 lbs (1814.4 kg)
- Average length – 8 ft (2.4 m)
A close relative of its buddy above, the hoodwinker sunfish is a relatively ‘new’ discovery. It was only identified as its own species in 2017!
This sunfish is a chameleon of the sea. Its coloring and patterning can change to match its surroundings, making it very difficult to spot. Which might explain why it took so long for us to discover it!
Hoodwinker sunfish are found in the southern hemisphere, in waters off of Australia, New Zealand, Chile and South Africa. They can reach lengths of up to 12 feet and weigh over 4000lbs. That’s almost double the size of the ocean sunfish!
Like its cousin, the hoodwinker sunfish has a small mouth and a large, flat body. But its coloring is much more drab, often varying shades of brown and grey.
Despite its impressive size, the hoodwinker sunfish is rarely seen and little is known about it. Scientists believe that it might be a common species that we’ve just never noticed before!
If something of this colossal size was only discovered in the 2000s and hangs relatively close to the sea surface, can you imagine what else is out there? Especially in the depths!
Number 1 – Sharptail Mola
- Average weight – 4000 lbs (1814.4 kg)
- Average length – 10 ft (3 m)
Edging out the hoodwinker by a few feet is our number 1! Sharptail Mola was discovered much earlier than the hoodwinker, but it’s only recently that we’ve realized just how big these fish can get.
Though generally much bigger, they’re often confused with their close relatives, the ocean sunfish. But they can be distinguished by their long, pointed tail fins. These fins can be up to six feet long!
Sharptail molas are the heaviest bony fish in the world. These gentle giants are found in all major oceans, often near the coasts. They tend to stick close to the surface, which is where they’re most often seen.
Their size and weight vary depending on the individual fish, but they can reach lengths of up to ten feet and weights of well over 4000lbs. That’s the same weight as an African elephant!
Like their friends above, they are often seen basking in the sun near the ocean’s surface. But their slow movements and large size make them easy prey for sharks and other predators should they decide to entertain the idea.
Despite their calm nature, sharptail molas are an important part of the ocean’s ecosystem. They help to keep populations of smaller fish in check by eating vast quantities of them.
That’s it for our list of the biggest saltwater fish! Did any of these surprise you? Let us know in the comments below! And be sure to check out our other blog posts for more fascinating information about our wild world!
