African lungfish

Protopterus annectens

African lungfish live in swamps, backwaters and small rivers in West and South Africa. They are widely distributed and are carnivores, eating frogs and other small fish.

Lungfish behavior and facts

  • When the shallow water it lives in evaporates during dry spells, a lungfish secretes a thin mucus layer around itself that dries into a cocoon.
  • It can live out of water in this cocoon up to a year, but usually only until rains return While out of water, its lungs enable it to breathe air.
  • Lungfish may hibernate by chewing into the soil and debris at the bottom of a waterway, ejecting mud from the gills as it burrows down. It digs one to nine inches below the surface, then wiggles around to create a bulb-shaped chamber. When the chamber is complete, the fish rests, with its nose pointing upward. In water, it can survive up to 4 years in this state; its metabolic rate slows and energy comes from the breakdown of muscle tissue.

From birth to death

  • Eggs are laid in a nest in a weedy area
  • Larvae have external gills that are reabsorbed during metamorphosis
  • Males guard the newly hatched young up to two months

Vital statistics

  • 6.5 inches

Status

Least concern

Lungfish, the Oregon Zoo and you

Njaa

The zoo's lungfish, named Njaa, lives in the Africa Rainforest exhibit. Its daily diet consists of smelt, small mice, earthworms and the occasional live crayfish it receives for enrichment. Swahili for "hunger," Njaa was named for its aggressive eating habits and lightening fast attack...