Confinement cattle-feeding operations have been associated with large populations of starlings (Sturnus vulgaris) during the winter months. Starlings can eat nearly 1 kg each of feed per month (Besser et al. 1968). In the first of our 2 studies, we evaluated feed selection and feed depredation by starlings using 5 concentrate-based cattle finishing diets. Four diets evaluated were in traditional meal-type form, and 1 diet was an extruded pellet. We placed rations into a section of the feed trough that we made accessible to starlings but not to cattle. Of the original 13.6 kg of steam-flaked corn and alfalfa hay ration placed into the feed trough at 0750 hours, only 1.9 kg (P \u3c 0.05) of residual feed was recovered after starlings returned to their evening roost. Starlings preferentially selected steam-flaked corn (i.e., starch), thereby concentrating the crude protein and crude fiber fractions (P \u3c 0.04) in residual feed. We observed similar trends for feed disappearance for the other meal-type rations. However, crude protein content was similar (P ≥ 0.10) between fresh and residual feed for dry-rolled corn and alfalfa hay diet and for steam-flaked corn and corn silage diet. Quantity and chemical composition between the fresh and residual extruded pellets were similar (P ≥ 0.57). In Experiment 2, the amount of feed delivered increased 36% for cattle (n = 13) that were fed traditional meal-type ration compared to cattle (n = 13) that were fed extruded pellets during a period of severe starling infestation. Following seasonal dispersal of starlings in early March, feed deliveries of traditional meal-type ration decreased to prestarling levels, while feed deliveries of extruded pellets remained unchanged. Starlings consumed 2,327 kg of feed from troughs with a total value of 563throughoutaperiodof47days,increasingdailycostofproductionbyapproximately0.92 per feedlot animal
