Danube bleak gravel bottoms. The females arrive later and deposit about twenty thousand eggs which stick to stones and gravel. These hatch after two or three days and the larvae stay among the gravel for another ten days before moving to backwaters and shallows where they feed on zooplankton, insect larvae and algae. The juvenile fish migrate down stream in the autumn or the spring of the following year. They may become mature in four to five years. Danube bleak The Danube bleak or Caspian shemaya ("Alburnus chalcoides") is a species of freshwater fish in the family Cyprinidae. It is found in
Whale Monodontidae (belugas and narwhals), Physeteridae (the sperm whale), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales). Whales are creatures of the open ocean; they feed, mate, give birth, suckle and raise their young at sea. So extreme is their adaptation to life underwater that they are unable to survive on land. Whales range in size from the and dwarf sperm whale to the and blue whale, which is the largest creature that has ever lived. The sperm whale is the largest toothed predator on earth. Several species exhibit sexual dimorphism, in that the females are larger