American Oceans

Giant Sea Bass

The Stereolepis Gigas, or giant sea bass, is an enormous fish that dwells in the Northern Pacific. It can grow from a few inches to the height of the tallest person to ever live.

Giant Sea Bass Stereolepis Gigas in Northern Pacific

Despite the name, the giant sea bass isn’t technically in the seabass family (Serranidae) but rather the wreckfish family (Polyprionidae).

The giant sea bass lives a lengthy lifespan – almost comparable to the average human’s life expectancy.

Even with the fish’s extended time on Earth, it is a critically endangered species, with only about 500 individuals thought to exist

Characteristics & Appearance

Giant sea bass are massive reef dwellers that are unmistakable during rare encounters with them. While most of their recognizable characterization can be attributed to the fish’s size, it also has a few other notable features that distinguish it from other aquatic life.

Weight & Length

The giant sea bass is only about 6 inches in the first year of life, but it can grow over 7 feet once it reaches maturity.

While the average length of the fish is just over 7 feet, there have been accounts of the fish reaching 8 feet and even 9 feet long.

Likewise, the weight typically falls between 500 to 600 pounds, but there are claims of up to 900 pounds.

Physical Characteristics & Color

In addition to its massive body size, the giant sea bass can be identified by its large, gaping mouth, which it uses to swallow up prey whole.

Giant Sea Bass triangular dorsal fin black color

Within this gigantic mouth is a bunch of small, blunt teeth. The color of the giant sea bass changes from when they are juvenile to adulthood.

They begin with pale orange scales and black patches and eventually transition to a grayish, sometimes black hue. Even after maturity, the fish retains the dark spots on its body,

To glide graciously through the sea, they have a triangular dorsal fin that sits on the lower half of their back and a pectoral and pelvic fin on each side of their body located near their gills.

Additionally, it has a singular anal fin on its belly, parallel to the dorsal fin. The giant sea bass can also be defined by its thick lips, sharp cheekbones, big eyes, and rounded head.

Lifespan & Reproduction

One of the most prominent facets of the giant sea bass is its exponentially long lifespan. They can typically live to be 70 – 75 years old, but there are many instances of the fish living beyond 75 (according to estimations made when studying its ear bone).

The giant sea bass takes a little over a decade to mature and will begin reproduction anywhere from 12 – 15 years old. They reproduce during summertime and migrate to specific generational spawn locations to do so.

Once a female reaches a designated breeding ground, it will release up to 60 million eggs ready to be fertilized.

Fertilized eggs absorb water and gain the characteristic of buoyancy, which will then float to the surface.

They spend about a month as larvae gliding on topwater, then sink into the ocean when they are ready to begin the next phase.


The giant sea bass lives in the Northern Hemisphere of the Pacific ocean just shy of the equator. They dwell in dwindling numbers alongside the coast of Northern California to Mexico.

They are most abundant in the top half of the California bay and along with the Channel Islands.

They can commonly be found in reefs and around islands but are known to occasionally venture away from these habitats for various reasons such as migration and hunting.

Where Do Giant Sea Bass Live?

The giant sea bass typically swims along the bottom of rocky coral reefs that are abundant with kelp beds and thrive with an active aquatic ecosystem.

Giant Sea Bass live in rocky coral reefs

The colossal fish spends its day slowly gliding over these reefs hunting for food. While the giant sea bass usually stays in these reefs, they will sometimes stray from them to find food.

In these instances, the hunt may take the fish far from its local reef to sandy patches where other creatures such as squid and octopus spawn.

Food & Diet

The giant sea bass is a carnivorous fish and an apex predator. They’ll consume most fish, crustaceans, and even small sand sharks on occasion.

Giant Sea Bass hunting small sand sharks

The fish will slowly scrounge along the bottom of a reef until it ensnares its prey in its humongous mouth with a sudden and swift movement.

What Do Giant Sea Bass Eat?

Despite the fish’s tendency to slowly drift through the water and its seemingly sluggish body, the giant sea bass is capable of rapid bursts of quick movement and is a highly potent hunter.

Once the unassuming goliath looms over its prey, it will unhinge its giant jaws and inhale the unsuspecting creature whole.

Through the speed of the fish propelling forward and the rapid opening of its colossal jaw, these movements create a vacuum effect that sucks in its prey.

The fish’s large body makes it hard to hunt through conventional means, such as chasing down a target in a battle of endurance, and thus must resort to other tactics to find food.

Due to its inability to move fast for long durations, the fish will typically look for its food crawling at the bottom of reefs underneath the sand and in cracks and crevices.

They have also been known to be ambush predators as they will hunt mid-water fish using kelp to conceal their presence.

The giant sea bass’s diet consists of various fish, crabs, lobsters, shrimp, stingrays, skates, octopi, squids, and even small sharks. There isn’t anything the fish won’t eat just as long as the animal can fit inside its mouth.

Threats & Predators

Even though the giant sea bass has substantial reproductive potential, few natural predators, and a tendency to eat most animals it can catch, the human threat has impacted the fish most heavily. It is why the numbers of these fish are so low.

Human Threats

This fish was heavily hunted in the early 1900s. As a result, had seen a heavy decrease in population over the next century.

While Californian fisheries were banned from catching and keeping these fish in the 90s, the damage had already been done, and the fish became critically endangered.

Climate Change & Global Warming

Since not much about the giant sea bass is known, and studies on the fish are limited due to the small population size, there aren’t any conclusive analyses about the effects of climate change on the fish.

It can only be assumed that global warming will affect the giant sea bass similarly to other fish native to its habitats.


Being such a large species and its status as an apex predator, the giant sea bass doesn’t have many predators aside from humans. The only real threat to the fish is great white sharks, which are another vulnerable species.

Other Threats

Since the greatest threat to the fish has historically been overfishing, all other potential hazards have been oversights.

With that said, it can plausibly be assumed that since the giant sea bass is indigenous to coral reefs, the destruction of these reefs is probably their second most significant threat.

Conservation Status

The giant sea bass is critically endangered, with only an estimated population of around 500 remaining instances.

Giant Sea Bass conservation due to endangered population

The International Union for Conservation of Nature gave it the status of critically endangered in 1996.

While scientists hope to see the comeback of this animal, studies have yet to indicate anything about their progress.

It is illegal to hunt and sell these fish, and all occurrences of accidental capture are to be returned alive to the water.

Fun Facts About Giant Sea Bass

  • Despite efforts to conserve the fish, the fish’s slow maturity rate of 12 years hinders most research. This means only two generations of the fish could have spawned and reproduced since 1996.
  • Small fish often cover the giant sea bass and ride alongside its body. These “cleaners” eat dead skin and parasites off of it.
  • Recent studies of the fish have indicated that there may be an underlying population of it in the unsurveyed waters of Mexico, but this is concurrently only speculation.

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