Color vision and spectral sensitivity in tunas and marlins.

To determine the presence of color vision in tunas and marlins, S-potentials were recorded from the isolated retinae of yellowfin tuna, bigeye tuna, albacore, striped marlin, Pacific blue marlin, and black marlin. No chromaticity type S-potential was recorded. This finding indicates that these fishes are probably color-blind. The distribution of relative amplitude at each stimulus wavelength obtained from the records showed that the maximum sensitivity is at wavelengths between 492 and 522nm in albacore and between 458 and 492nm but closer to 492nm in the others.