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Marine Animal Encyclopedia

Three-spined Stickleback Gasterosteus aculeatus

The three-spined stickleback is equally at home in fresh water and sea water. It has three sharp spines on its back and a series of bony plates along its sides. This species is best known for its breeding behavior, which involves the male building a tunnel-like nest of plant material into which he entices one or more females to lay their eggs. He fans oxygenated water over the eggs as they develop.

Three-spined Sticklebackzoom image
  • Order Gasterosteiformes
  • Length 4 in (11 cm)
  • Weight Not recorded
  • Depth 0–330 ft (0–100 m)
  • Distribution Temperate waters of north Atlantic and north Pacific
Three-spined Stickleback Habitat Mapzoom image