Chemical cues in orientation and navigation

Nec vident terras, sed in odorem earum natant. (They don t see the land, but swim following its smell.) 

Mexican coast with its aromatic vegetation (Faak, 1990). There is every reason to expect that wild animals exploit such landscape odors for their needs. 

In an experiment, hatchery-reared Coho salmon have been imprinted to the artificial odors of morpholine, a heterocyclic amine (C4H9NO 5 x 10 mg/l)  

The cited experiments by Hasler and coworkers demonstrated fish stream imprinting (Scholz etal., 1976 Hasler eta/., 1978). 

M-imprinted fish PA-imprinted fish Control fish 

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