Audience effects are described as the sensitivity to the presence and nature of recipients. When an animal gives a vocal signal, the signal can be received by intended audiences, those who are the target of the signal such as conspecifics, and/or unintended audiences, such as predators. A signaler can vary the properties of their signal, the frequency, and type depending on the perceived audience. Audience effects demonstrate that first, signallers have volitional control over signal production and second, signallers are aware of receivers' perceptual states and can modify their signals accordingly. Tying back to other themes, audience effects may show that signallers can alter the referential and affective properties of their signals.
Examples: