Comparison of two models for estimating mortality from baitings with Compound DRC-1339 Concentrate avicide

► We compared two quantitative approaches for assessing DRC-1339 baiting of blackbirds. ► Semi-mechanistic models produced mortality estimates 29% lower than linear models. ► Semi-mechanistic models estimated over twice as much bait was eaten per feeding bout. ► Variance in mortality among species was much greater for linear models. ► Semi-mechanistic models estimated lower mortality during periods of colder weather.