Head to head
Common Minnow vs Three-spined Stickleback
Common Minnow
VS Three-spined Stickleback
The common minnow and the three-spined stickleback are two of the smallest and most familiar freshwater fish of Europe, and children catching tiddlers in a net often scoop up both.
| Common Minnow | Three-spined Stickleback | |
|---|---|---|
| Scientific name | Phoxinus phoxinus | Gasterosteus aculeatus |
| Relationship | A member of the carp family | A member of the stickleback family, not closely related to the minnow |
| Size and shape | Usually only 6 to 8 cm long, with a streamlined, olive-green body and a dark stripe along its side | A small fish of about 5 cm, with bony side plates instead of scales |
| Defence | No spines, but an injured minnow releases a chemical alarm that makes the whole shoal flee | Two or three sharp spines on the back and a stout spine in place of each pelvic fin, all of which lock upright and make it awkward for a pike or perch to swallow |
| Breeding colours | Males develop a red belly and throat, a blackish head, and rough white bumps called tubercles | Males develop a bright red throat and belly and blue eyes, and the red patch triggers aggression towards rival males |
| Nest and young | Gives no special care to its eggs, which are shed over gravel | The male builds a tunnel-shaped nest from plant fragments glued with a kidney secretion called spiggin, fans the eggs, and guards the young alone |
| Habitat | Clear, cool streams, rivers, and lakes with gravelly or sandy bottoms, sensitive to pollution | Ponds, ditches, streams, lake margins, estuaries, and rock pools, in fresh, brackish, and inshore coastal water |
| Range | Native to streams and rivers across Europe and northern Asia | Right around the Northern Hemisphere, in Europe, northern Asia, and North America |
Common Minnow vs Three-spined Stickleback: common questions
Which one has spines?
The three-spined stickleback, with two or three sharp spines on its back and a stout spine in place of each pelvic fin, while the minnow has none.
Which male builds a nest?
The stickleback male, who builds a tunnel-shaped nest from plant fragments, leads a female to it, and guards the young alone.
How does a minnow warn its shoal?
When its skin is injured it releases a chemical that warns other minnows, causing the whole shoal to flee.