According to PBS, the average life span of a shark is 25 years. Life expectancy can vary among shark species. Sharks tend to live much longer in the wild than in captivity.
The biggest animal in the ocean, and possibly the largest animal ever to live on Earth, is the blue whale. The maximum recorded weight for a 98-foot blue whale exceeded 209 tons. Longer whales, up to 110 feet, have been seen but not weighed.
Shrimp have been known to live from 1 year to as long as over 20 years in captivity. According to the Northeast Fisheries Science Center, the life cycle varies based on geography and the species of shrimp.
The 42 known species of dolphins live in the waters of oceans and rivers all over the world. Dolphins are found everywhere, from shallow coastal waters to the deep of the open ocean, and they migrate to and from certain areas due to water temperature and food availability.
The main difference between a colossal squid and a giant squid is size. The colossal squid's body is larger than the giant squid's, but the colossal squid has shorter tentacles. Colossal squids can grow to more than 1,000 pounds, while giant squids only reach about 600. Colossal squids also have larger beaks than giant squids, and their limbs have sharp hooks that swivel.
Found in Arctic waters, the narwhal is related to the bottlenose dolphin, beluga, porpoise and orca. It is easily distinguishable by the sword-like spiralling tusk that grows through the upper lip of the male. The male's tusk can grow up to 8.8 feet in length although the female grows a much smaller tusk. The narwhal grows anywhere between 13 to 20 feet and weighs up to 3500 pounds.
Narwhals live in the Arctic Ocean in the areas near Russia and the Atlantic Ocean. They have been found as far east as eastern Russia and as far south as Greenland.
Birds of prey, sharks, large fish, eels and crocodiles are predators of the sea snake. Sea snakes live in shallow waters and breathe air using a long lung that also assists in buoyancy. Although the sea snake isn't aggressive, it produces some of the deadliest venom in the world.
Most sea sponges are detrivorous, meaning they consume organic debris and various microbes that drift through ocean currents. Harp sponges, however, are carnivorous and use hooks located on their arms to catch shrimp and other small animals.
Adult killer whales are top-end predators and have no need to protect themselves from natural enemies. Killer whale calves are protected by their mothers and by other members of the pods to which they belong.
Cnidarians have groups of similar cells that work together as tissues, while sponges have no tissues, only disconnected regions of specialized cells. Each group has a type of cell unique to their group: Sponges have collar cells, and cnidarians have nematocysts. No sponges are capable of movement as adults, while some cnidarians move as adults.
The flesh of the barracuda sometimes carries the toxin ciguatera, although it is regularly eaten by humans. Symptoms of ciguatera poisoning include nausea, vomiting and diarrhea. Neurological symptoms, such as headaches, paresthesia and vertigo, often follow. Scarce treatment options exist for ciguatera poisoning, although recovery is possible in time.
Seahorses feed on small crustaceans. Some of the favorites for seashores are shrimp and zooplankton, though they will eat nearly any live food.
Sand dollars eat tiny bits of organic material they find on the sea floor. Sand dollars are echinoderms, which means they have spines. They get the name "sand dollar" because their skeletons look like large coins when they wash up on the beach.
Sea cucumbers expel their internal organs through their anus to distract and ward off predators. They also evacuate their organs on a seasonal basis, regenerating them afterwards. In addition, some sea cucumbers have special, sticky tubules, part of their respiratory system, which they spew at predators.
When you put a seashell to your ear you are not hearing the ocean, you are hearing the ambient noise coming from inside your ear and around you. The seashell captures and amplifies the noise, which resonates inside the shell and sounds like the rolling waves of the ocean. This effect is called seashell resonance.
A baby blue whale gains about 200 pounds during its first day after birth. In fact, the young whale maintains this daily weight gain throughout its entire first year of life by feeding exclusively on its mother's milk. Each day the newborn also grows about one inch longer.
Coastal bottlenose dolphins prefer bottom-dwelling fish and invertebrates, while offshore dolphins eat a variety of fish and squid. More ingenious feeders have been known to trail fishing boats, in the hopes of snagging some leftovers.
Whales and dolphins beach themselves, or end up beached, for reasons ranging from injury and illness to polluted water and simply becoming stranded at low tide. When these creatures travel in pods, the entire pod is likely to end up beached if the leader accidentally strands itself on shore, explains Mental Floss.
Of the 15,000 species of bivalves known as clams, some have life cycles of only one year. Individuals of one species called the ocean quahog, or Arctica islandica, however, are among the oldest living animals on Earth, with one captured specimen measured to be more than 500 years of age.
Angler fish, Pacific Viperfish, Wolfish, Goblin Shark and Sloane's Viperfish are just a few of the terrifying fish lurking in the ocean's depths. Once you move past the point where light reaches, the world's oceans turn into a terrifying place filled with strange creatures.