Expected probability of detection (a) as a function of the scaled budget <i>B</i>′, with <i>c</i>′ = 0.5, when detection rate is assumed to be variable (solid line, θ = 1.5) compared to when it is assumed to be constant (dashed line).

<p>Likelihood that the failed-detection probability <i>Q</i> is less than the prescribed value <i>Qc</i> (b) as a function of the scaled budget <i>B</i>′, with θ = 1.5 and <i>c</i>′ = 0.5, when detection rate is assumed to be variable (solid lines) compared to when it is assumed to be constant (dashed line).