Do coral reef fish learn to avoid unpalatable prey using visual cues?

► Coral reef fish (blueheads) can learn to avoid unpalatable prey on the basis of prey colour alone. ► Learned avoidance was dependent on colour; fish were unable to avoid some colours. ► Fish rapidly learned to overcome a strong pre-existing bias against red prey. ► There was no difference in the ability of fish to avoid prey on the basis of colour or pattern. ► Blueheads continually assess and adapt to prey palatability using visual cues.