The Encyclopedia of Animals
Squid
Squid (Teuthida) Overview Squids are members of the mollusk family. They have eight arms and two feeding tentacles, which all extend from around the mouth on the head. While many mollusks have a protective shell, squids do not. The body, or mantle, of squids is soft, as are the two steering fins on either side. Adults of the various species range in size from less than an inch long to 50 feet or more.
Habitat and Future of the Species There are as many as 300 species of squid that live throughout the world’s oceans. Squids feed on fish and other marine animals, including other squids. Fish, seals, sharks, whales, penguins, birds, and humans eat squids. Fishing of many species of squid takes place around the world. In many countries, squid is a popular food. (Squid is known as “calamari” when it is served as food.) No species of squid is threatened or endangered.
Various Species of Squid Longfin squids are found in the Atlantic Ocean. There are many of them in the coastal waters between Massachusetts and North Carolina. They can be found anywhere from the surface to depths greater than 1,500 feet. Image credit: Wikipedia/public domain
Interesting Features Squids are invertebrates with huge eyes and a large brain. They can be many different colors. Some species have special cells in their skin that allow the animal to change color. They might change color to hide. They may also use flashing color patterns to communicate with one another while hunting. The mouth of the squid contains a hard, sharp beak. It is used to chop up food. The beak is so hard that if another animal eats a squid, the beak cannot be digested. It stays in the stomach of that animal. This is known because beaks are often found in the stomachs of fish and whales. Squids use ink to escape from other animals. They shoot the harmless ink into the water when they are threatened. The ink creates a dark cloud in the water. This allows the squid to swim away, unseen. Squids swim tail first. They take in water and then push it out to move through the water.
Image credit: NOAA
Longfin squids grow fast, but they only grow to be about a foot long. They live 6 to 8 months. Right before they die, females produce about 3,000 to 6,000 eggs. Eggs hatch between 11 and 26 days later, depending on water temperature. Longfin squids are pink or orange and spotted with brown or purple. They can change their color and patterns. This helps them to escape or hide. Their fins are longer than many other species, at least half the length of the mantle. Like other squids, their heads have large eyes. Market squids, also called Pacific loligo squids, are found from southern California to Alaska. They live from the ocean surface to depths below 2,000 feet. They stay in the salty ocean and are rarely found in bays or river mouths. Market squids migrate in enormous schools from Alaska to Mexico.
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The Encyclopedia of Animals
Squid
Image credit: NOAA
Market squids grow quickly to a length of one foot. They only live about one year. They gather in large schools to lay eggs right before they die. Females produce about 20 egg cases, with each case containing about 200 eggs. Females lay the egg cases on the sandy floor, building large mounds of egg cases. Eggs take several days to a few months to hatch, depending on water temperature. Market squids are milky white and purple, but their coloring can change based on environmental conditions. Giant squids have been somewhat of a mystery. There were reports of huge and dangerous squids in the oceans, but the only proof that they existed were dead squids found on beaches. Based on those discoveries (shown in red on the map below), the range of giant squids is thought to be worldwide.
Image credit: NASA
Scientists know very little about giant squids. Like all squids, they have a mantle (body), eight arms, and two long feeding tentacles. The inside of the arms and tentacles have hundreds of suction cups that help the animals grab their food and pull it into their mouths. Giant squids have eyes as large as 10 inches across. This probably helps them see in the darkness of the deep ocean.
In 2002, photos were taken of a live giant squid near the ocean’s surface. In 2004, scientists captured photos of a giant squid near the ocean floor. In 2006, a giant squid (photo at right) was photographed coming out of the water to attack a smaller squid being caught on a fishing line. Image credit: AP/Tsunemi Kubodera, National Museum of Nature and Science of Japan
In 2012, a 9-foot-long giant squid was filmed from a manned submersible in the Pacific Ocean near Japan. Based on squids that have been found on beaches, this squid was a small one. Some scientists believe that giant squids could reach a total length of more than 50 feet. Antarctic squids seem to be even more out of reach than giant squids. They are believed to live only in the cold waters surrounding Antarctica. The body of the Antarctic squid is larger than the giant squid, but the arms and tentacles are shorter. It is the heaviest animal of its kind on Earth. The largest Antarctic squid ever seen was caught in 2007. It weighed about 1,000 pounds. The animal was caught live (see photo). It was then frozen and later shown at the Museum of New Zealand. Image credit: AP/New Zealand Fisheries
Other information about Antarctic squids has been taken from smaller ones caught in nets. Parts of these squids have also been found in the stomachs of whales. Sources for information: Washington Department of Fish and Wildlife; National Oceanic and Atmospheric Administration’s National Marine Fisheries Service; Associated Press; NASA
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