Some estimates report the world’s oceans are home to 20,000 species of fish. Ocean fishes come in all shapes, sizes, colors and live in drastically different depths and temperatures. Despite this diversity, the United Nations Food and Agriculture Organization reported in 2016 that 89.5% of fish stocks are fully fished or overfished.
Learn fun facts and how you can help you favorite ocean fishes – from Atlantic bluefin tuna to blue tang – by clicking a species below.
Adult Patagonian toothfish reach lengths of up to 7.5 feet (more than 2 m) and weights of 220 pounds (100 kg). These large adults live near the bottom of the sea, in very deep water (over 12,000 feet/3800 m), where they hunt other fishes, squids, and crustaceans. They are known to be the occasional prey of deep-diving mammals … Read more
Though they spend most of their time in the deep, common fangtooths are known to migrate toward the surface, at night, following their preferred prey of crustaceans and other fishes. Common fangtooths are more active than many other deep-sea fishes and seek out food, rather than being purely ambush (sit and wait) predators. Their huge mouths and … Read more
Pacific sardines are filter feeders that feed on a variety of phytoplankton and zooplankton. Though they filter very small prey, they use their relatively large eyes and exceptional eyesight to increase the density of prey in the water that they filter. This strategy is in stark contrast to that used by the very large bodied filter feeders … Read more
It gets its common name from the adult coloration, which includes an obviously blue head on an otherwise green body. Juveniles are solid yellow, or nearly so, with a black spot on the dorsal fin. The numerical success of the bluehead wrasse is apparent to anyone who has visited a Caribbean reef; it is one of the … Read more
Like all flatfishes, Pacific halibut have both of their eyes on the same side of their heads, and they live on the seafloor, lying on their blind side, with their eyes facing the open water column. This species is one of several “righteye flounders,” with both eyes on the right side of the head. Amazingly, when they … Read more
This species is known for its long bill that grows from the front of its head. Blue marlin use this bill to stun their prey by slashing their heads in a side-to-side motion, knocking potential prey unconscious, and making it easier to catch. The blue marlin’s bill differs from the swordfish’s and the sailfish‘s by being round and … Read more
Life in the deep sea is difficult, so many fishes there have special adaptations to improve their ability to feed and to mate. Deep sea anglerfish may not regularly encounter suitable prey, so they have very large mouths and stomachs and long, pointy teeth in order to facilitate capturing and swallowing anything that they find. They … Read more
Though generally considered to be foraging predators, which lazily search the reef surface for food, Banded butterflyfish actually utilize a variety of feeding strategies. Some (often in pairs) do forage on the reef surface. Others form larger schools that visually hunt tiny plankton in the water column above the reef. Still others are known to engage in cleaning … Read more
Flashlight fish are predominately nocturnal and are only rarely observed by SCUBA divers during the day. They spend most of the daylight hours hidden in caves or holes in the reef surface. They feed at night away from the reef surface and likely use their light organs to help them locate small, planktonic prey. Like many species that … Read more
The Atlantic goliath grouper, like most groupers, is an ambush predator and eats fairly large fishes and invertebrates and even small sharks. Reefs with large numbers of predators, like Atlantic goliath groupers, are known to be healthier than reefs with no predators, so this species may represent an important part of the reef food web. Atlantic goliath … Read more
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We have already protected nearly 4 million square miles of ocean and innumerable sea life - but there is still more to be done.