Reef fishes from the genus Apogon use olfactory cues to allow them to remember where they live, and find their way home if they get lost.
Freshwater fish remember where they live and find their way home by sniffing out the smells left on the substrate by members of their species.
Scientists had believed that marine fishes probably used the same method of using their sense of smell to detect chemical cues in the water, and now new research has shown that this is right.
A team of scientists working at the Institute of Molecular Bioscience at University of Oslo in Norway, which is due to be published later this year in the journal Chemical Senses, says Apogon use their sense of smell to hold their station and find their way back to their reef if they get displaced.
The group studied three apogonid species, including Five-lined cardinals, Cheilodipterus quinquelineatus, Ghost cardinals, Apogon leptacanthus and Split-branded cardinals, Apogon compressus, on Lizard Island Research Station in Queensland, Australia during 2001 and 2002.
The study found that groups of C. quinquelineatus and A. compressus preferred artificial reefs that had previously been occupied by members of their own species.
The team wrote: "Individual C. quinquelineatus preferred scent of conspecifics from their own reef site to that from another site.
"They also preferred the scent released by artificial reefs previously occupied by conspecifics of their reef site to that of similar reefs previously occupied by conspecifics of another reef site.
"No discrimination between species from the same reef site was obtained in experiments with individual fish."
For more details on the study see the paper: Doving KB, Stabell OB, Ostlund-Nilsson S, Fisher R (2006) - Site Fidelity and Homing in Tropical Coral Reef Cardinalfish: Are They Using Olfactory Cues? Chemical Senses. In Press.