Eels

EELS

There are two main types of eels - the shortfin and longfin.

Eels do not have scales.   Many people find eels revolting, probably because of their slippery skin because of the mucus.

When eels begin their life they are a tiny one millimeter long. During their life, they can grow up to two meters long.  Compared with many other fish, eels are slow growing.  A longfin may grow only between 1525 mm a year.  They can also live for many years. Large longfins have been estimated to be at least 60 years old.  The biggest eels are usually old females.  The biggest longfin eels weighed about 40 kg.

Eels eat live food. Small longfin eels living amongst the river will feed on insect, worms and water snails. When they get bigger, they begin to eat  fish. They will also eat fresh-water crayfish and even small birds like ducklings.  Eels hunt by smelling not much using their sight.  They have tube nostrils from their head to their upper lip. They also have  a very large mouth with rows of small, sharp, white teeth.   

Longfin eels breed only once at the end of their life. When they are ready to breed, they leave New Zealand and swim 5000 kilometres up into the tropical Pacific probably in deep ocean somewhere near Tonga.  When they reach their destination, the females lay millions of eggs that are fertilised by the male. The adults never return as they die after breeding.

Extra fact

They say if you are really lucky you could see a golden longfin