Hobbies And Interests
Crabs and Lobsters
Several types of crustaceans -- shelled animals that include the shrimp and crabs -- scurry about on the ocean floor. The large-clawed spider crabs live more than 11,000 feet below the ocean's surface, using their elongated legs to walk for long distances across the ocean floor. Sometimes, they have to rely on foodfalls, dead creatures and food particles that have drifted toward the bottom of the ocean. The squat lobster, which is related to the king crab, lives at depths of about 6,000 feet. Because it cannot see, this eerie, light-hued lobster uses its sense of smell to locate food.
Fish
In murky environments, fish such as the stoplight loosejaw emit their own light. Unlike other bioluminescent creatures that produce greenish-blue light, the loosejaw illuminates its surroundings with a red light. Creatures of the deep sea do not find food easily, so fish such as the black swallower have elastic stomachs that allow them to consume large amounts of food at one time. Because finding mates at these depths proves difficult, male members of a species of angler fish attach themselves to the bulkier females. The connection becomes permanent, and the male loses all biological functions except for sperm production.
Isopods
A large relative of the sow bug, the giant isopod can exist at depths close to 8,500 feet. Both the Atlantic and Pacific Oceans house these crustaceans. These invertebrates measure approximately 2 feet in length and feed on the corpses of fish, whales and other invertebrates. Scientists theorize that the deep-sea isopods reach such colossal sizes, in contrast to land isopods, because the lower temperatures induce longer lives, allowing the organisms to grow for extended periods of time.
Mollusks
With food sources relatively scarce at greater depths, many mollusks -- soft-bodied animals enclosed in shells -- rely on dead animals or food particles that sink to the ocean bottom. Predatory mollusks such as the cone shells use tongue-like projections to pierce and deliver poison to unfortunate creatures roaming nearby. Parasitic mollusks such as the Eulimidae snails have evolved ways to attach to and feed off of other deep sea creatures. Some clams, limpets and mussels live in the heated environment of ocean vents and deep fissures in the sea floor called ocean trenches.
Squids
Ancient tales have described slimy creatures many times the size of a human and armed with numerous squirming tentacles. The giant squid named Architeuthis, once dismissed as a figment of a storyteller's imagination, has been found near beaches and caught in fishing nets all over the world. The animal has eight 10-foot arms and two 30-foot tentacles to capture prey. The Architeuthis serve as food for the sperm whale. In 2004, Japanese scientists took the first underwater photos of the giant squid at depths of 3,000 feet. The giant squid lives only about five years, rapidly growing to a length of 60 feet.