Fish and marine life

In short: Fish are vertebrates that live in water and breathe with gills. Besides them, the sea is home to molluscs, crustaceans, jellyfish and mammals such as whales.

In more detail: There are about 35,000 fish species. The world’s oceans cover around 71 percent of the Earth.

In detail

• Bony fish: Most species; the swim bladder helps with buoyancy (auftrieb-und-archimedes).
• Cartilaginous fish: Sharks and rays.
• Gills: Take up oxygen from the water.
• Lateral line: Sense organ for current and pressure.
• Migratory fish: Salmon and eel migrate between fresh and salt water.
• Coral reefs: Species-rich habitats, threatened by warming and acidification (klimawandel-grundlagen).
• Overfishing: Many stocks are overused; labels such as MSC or ASC help with choice.
• Protection: Marine protected areas, avoiding plastic waste (plastikmuell-vermeiden-im-alltag).