
Attracted by the light of the moon shining on the sea, loligo squid gather by the thousands every March to mate and spawn in the shallow waters off Southern California. There are more than 300 species of squid, ranging in size from less than half an inch to over 60 feet in length. The loligo squid grows to approximately eight inches and, like all its close relatives, has eight short arms and two long tentacles that it uses to catch prey.
Food and Hunting: Squid eat fish and crustaceans primarily. The loligo catches a fish by grasping it in its long tentacles. It paralyzes its prey with venom produced by its salivary glands and bites off the prey’s head. The squid’s torpedo-shaped body enables it to move rapidly over short distances. It changes color to blend in with its surroundings and so becomes invisible to both its prey and predators. The squid’s only defense is to escape behind the dark clouds of “ink” that it squirts into the water.
Breeding: On moonlit nights in March, loligo
squid gather near the water’s surface. The group consists of males and
females that are ready to mate. The males find mating partners as quick
as possible since the presence of so many other males creates competition
for available females. As a male becomes excited, his head and tentacles
become flushed. He then seizes a female and retrieves a sac of sperm from
his own body that he inserts into her body with one of his tentacles. The
eggs are thus fertilized in the female’s body and she then lays them in
jelly-filled sacs, each containing 200 to 300 eggs.
Each female produces approximately 20 sacs that
are joined together in flower-shaped configurations and are as large as
10 feet across. The sacs are attached to each other with a sticky secretion
that prevents them from being washed away. Tiny squid hatch from the egg
sacs three to four weeks later. They are moved and spread by coastal currents.
In three years they are fully grown and ready to mate.
Squid and Man: The breeding habits of the loligo squid make it particularly easy to catch. Fishermen in California catch the majority of squid in March, when the squid gather to mate. The squid are attracted to light, so the fishermen hang lamps on their boats to encourage them to rise to the surface. Several thousand tons of squid are caught each year. Still, because they produce so many eggs, the loligo squid are in no danger of becoming overfished. But fishing is controlled because, if the squid were hunted on a larger scale, it would endanger the other marine life that preys on the squid for food.
Key Facts: Sizes, Breeding, Lifestyle, and
Related Species:
Sizes:
Length: Head and body, 8 in.
Tentacles: Eight arms, 2 in. Two long
tentacles extend to 8 in. for catching prey
Breeding:
Sexual maturity: 3 years
Mating season: March
No. of eggs: Laid in sacs of 200-300.
Each female lays about 20 sacs at a time
Hatching: 3-4 weeks
Lifestyle:
Habit: Usually solitary, although
huge schools gather during mating season
Diet: Mainly fish
Lifespan: 3 years
Related Species: Closely related to the
common squid, Loligo vulgaris. Giant squid of up to 60 ft. (including tentacles)
are found in the northern Atlantic Ocean.
Distribution: The loligo squid is found
throughout the warmer waters off the west coast of North America, extending
south from San Francisco to Mexico.
Conservation: Although the loligo squid
is fished extensively each year, the fishing is controlled, and this species
is not yet in danger of extinction.
Features of the Loligo Squid: The arms and tentacles of all squid are covered with suckers to provide a powerful grip that is used when hunting. At the center of the tentacles is the squid’s mouth that has a horny beak with which it tears up prey before swallowing it. It has two well-developed eyes. In some species, notably those that live at great depths, eyes are also light-producing organs. Two long tentacles used for catching food. Eight arms, sometimes called short tentacles.
Did You Know:
The giant squid, Architeuthis, is the world’s
largest living invertebrate.
The giant squid’s only predator is the male sperm
whale. A live squid measuring 40 feet long has been found inside a male
sperm whale. Female sperm whales eat much smaller squid.
Squid possess the largest nerve fibers of any
animal.
The most dangerous squid are found off the coast
of Peru. They live in schools and hunt in the same manner as the piranha,
tearing their victims to shreds in seconds.
In 1961 a gold medallion was found inside a loligo
squid caught off San Sebastian, Spain. It had been lost by a swimmer in
Barcelona two years earlier and 900 miles away