Investigating carbohydrate-rich feed supplements and the feeding preferences of European starlings (Sturnus vulgaris)

Abstract

In the current ecological and ornithological environment in the continental United States, the European starling (Sturnus vulgaris) is one of the most common exotic bird species. After being introduced on the East Coast of the United States, the species spread rapidly across regions and ecosystems, significantly affecting the greater ecology of the nation and often disturbing local species populations. To better understand the behavior and preferences of this species, a study was devised to test the field responses of a population of European starlings in Lyon County, Kansas over a total period of 144 hours (during 48 individual observation periods) to assess and yield knowledge pertaining to their behavior and feeding patterns within a suburban environment. For this experiment, four feed alternatives (i.e., one control and three experimental) were prepared to test the impact of the utilization of carbohydrate-rich feed supplements on the degree to which the starlings would frequent a feeding location. The different feed offered to the local starlings would consist of either 300g of conventional bird feed, 200g of conventional bird feed and 100g of the supplement, 100g of conventional bird feed and 200g of the supplement, or 300g of the supplement, with the conventional bird seed acting as the control. The data suggest that the differences observed with relation to the feed alternatives were negligible, as demonstrated by the starlings preference for the different supplement concentrations (according to their feeding frequency for the four alternatives).