By Thomas P. Quinn, Craig A. Busack
Animal Behaviour, Volume 33, Issue 1, February 1985, Pages 51-56, ISSN 0003-3472, DOI: 10.1016/S0003-3472(85)80119-6.

Juvenile coho salmon, Oncorhynchus kisutch, were tested for responses to water conditioned by conspecifics in two-choice tanks. The fish preferred water conditioned by unfamiliar non-siblings over blank water, but preferred water conditioned by both familiar and unfamiliar siblings over non-siblings. These preferences suggest that coho salmon recognize their siblings by matching the phenotype of their tank-mates with unfamiliar conspecifics, and that chemical cues are sufficient for recognition.

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