Dither fish

Dither fish are aquarium fish used by cichlid owners to make some species of cichlids less afraid.Barlow G.W. 1968. Dither--a way to reduce undesirable fright behavior in ethological studies. Z. Tierpsychol. 25:315-318.  

Dither fish usually swim around the top of a fish tank. This behavior makes afraid fish less afraid. Fish that are not afraid hide less. The scared fish think (correctly) that no predators are in the tank.  

The technique is based on the ability of cichlids in an aquarium to use the behaviour of other fish species as a sign that the place they are in is safe.Loiselle P.V. 1979. On dither fish. Freshwater and Marine Aquarium Magazine November:30-34, 76-79 (also online). Good dither fish are usually schooling species, such as some Danio species, barbs and some tetra species.

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Category:Ethology
Category:Aquarium fish