Fish supply the greatest percentage of the world’s protein consumed by humans.
As a consequence, most of the world’s major fisheries are being fished at levels above their maximum sustainable yield; some regions are severely overfished.
Many fish are hermaphrodites, they can change sex during the course of their lives. Others, especially rare deep-sea fish, have both male and female sex organs
The Swordfish and Marlin are the fastest fish in the sea reaching speeds up to 121 external kph in quick bursts. The Bluefin tuna can reach sustained speeds up to 90 external kph.
Sharks attack some 50-75 people each year worldwide, with perhaps 8-12 fatalities, according to data compiled in the International Shark Attack File (ISAF). external
Although shark attacks get a lot of publicity, this is far less than the number of people killed each year by elephants, bees, crocodiles, lightning or many other natural dangers.
Conversely, between 20-100 million sharks are killed every year through fishing activities.
Blue whales are the largest animals to exist on our planet. They even exceed the size of the greatest known dinosaurs and have hearts the size of small cars.
More than 90% of the trade between countries is carried by ships and about half the communications between nations use underwater cables.
The speed of sound in water is 1,435 external m/sec – nearly five times faster than the speed of sound in air.
Antarctica has as much ice as the Atlantic Ocean has water.
After a total meltdown of the world’s ice, the oceans would rise 66 external metres.
The sea level has risen with an average of 10-25 external cm over the past 100 years and scientists expect this rate to increase. Sea levels will continue rising even if the climate has stabilized, because the ocean reacts slowly to changes. 10,000 years ago the ocean level was about 110 external m lower than it is now.
The average depth of the Atlantic Ocean, with its adjacent seas, is 3,332 metres; without them it is 3,926 m. The greatest depth, 8,381 external metres, is in the Puerto Rico Trench.
Oil is one of the ocean’s greatest resources. Nearly one-third of the world’s oil comes from offshore fields in our oceans. Areas most popular for oil drilling are the Arabian Gulf, the North Sea and the Gulf of Mexico.