In detail

The Oyster - Wanted Poster


Surname: Oyster
Other names: /
Latin name: Ostreidae
class: Shellfish
size: 10 - 40 cm (depending on the species)
mass: 50 - 200 g (depending on the species)
Older: up to 30 years
Appearance: unbreakable, gray shell
Sexual dimorphism: No
Nutrition type: Plankton filter (planktivor)
food: Plankton
distribution: Atlantic, Pacific
original origin: worldwide
Sleep-wake rhythm: /
habitat: Coastal zones and tidal waters
natural enemies: Oyster drills, crabs, starfish, seagulls
sexual maturity: ?
mating season: all year round
oviposition: up to 100 million eggs
social behavior: /
Threatened with extinction: No
Further profiles of animals can be found in the Encyclopaedia.

Interesting facts about the oyster

  • The oysters or Ostreidae describe a family of several genera and countless species within the shells, which primarily colonize shallow coastal zones and tidal waters.
  • The oyster is of great economic importance both as a food and as a producer of pearls.
  • It is considered a very old creature that already inhabited the earth over 250 million years ago.
  • Oysters are found in tidal areas as well as estuaries, where they filter hundreds of gallons of water a day to absorb nutrients and plankton.
  • For this reason, they are instrumental in preserving the ecosystems in which they live. But they are also extremely sensitive because even the smallest amounts of environmental toxins in water can lead to their death.
  • In the past, oysters were common in all seas. Due to pollution they are now found only in pristine parts of the Atlantic and Pacific, while they are already completely extinct in the Mediterranean.
  • To protect the sensitive soft body from predators, the oyster forms a shell composed of several layers, which consists of a very break-proof mixture of calcium carbonate and conchine and is lined on the inside with mother-of-pearl. It grows underground, which is why an oyster is completely immobile.
  • The shell consists of two halves, which are connected by a ligament and can be completely waterproofed. As a result, an oyster is able to survive up to two weeks outside the sea.
  • The soft body contains gills that serve for breathing and food intake.
  • Intruders and foreign bodies of organic and inorganic origin are rendered harmless by coating with mother of pearl.
  • The reproduction is two-sexed, some oysters change their gender in the course of their lives.
  • Per spawning process, up to one hundred million eggs are released into the water and then fertilized with sperm in open water.
  • The tiny larvae anchor with substrate three weeks after hatching. The subsequent metamorphosis to the adult shell survives only a portion of the young oysters.
  • Oysters serve many species of animals, especially the so-called oyster drills, as an important food source.
  • The oyster snails, called oyster drills, have a rasped tongue, the so-called radula, which cuts a hole in the oyster's shell. With their trunk, they then eat the nutritious oyster meat.
  • Various crabs, starfish and seagulls occasionally capture oysters.
  • As food for humans, only the Pacific Oyster, the European Oyster and the American Oyster are of importance. Other species native to the Far East, however, are bred for pearl production.
  • All commercially important oysters are grown in aquacultures, mainly in China, Japan, North Korea, France, Ireland and Holland.
  • In the wild, oysters can live up to thirty years.