How long the aquatic animals can remember the chemical search images?

In general, an acquired chemical serch image forms in the long-term memory of an animal during its learning (both in the nature or laboratory) and is used further as an etalon (template, specimen) to collate the receiving perceptual information.


In the aquatic animals, for example, the chemical search images can form in respect of odors of food, predators, school mates and other objects.

How long the aquatic animals can remember the chemical search images?

For example, American river crayfish, Orconectes virilis, trained during 2 weeks to eat freshly crushed zebra mussels, remember an odor of these molluscs without its refreshment within at least 20 days, but forget it after 40 days (Hazlett 1994). According to Brown and Smith’s (1994) laboratory experiments, fathead minnows, Pimephales promelas, lived in the nature in relatively permanent shoals of familiar mates but kept separately, remember an odor of former mates for over 2 months.

Basic References

Brown G.E., Smith R.J.F. 1994. Fathead minnows use chemical cues to discriminate shoalmates from unfamiliar conspecifics. Journal of Chemical Ecology 20, 3051-3061
Hazlett B.A. 1994. Crayfish feeding responses to zebra mussels depend on microor-ganisms and learning. Journal of Chemical Ecology 20, 2623-2630