Foraging Efficiency of Rural and Urban House Sparrows, <em>Passer domesticus</em>, Among Natural and Unnatural Obstacles

Urbanization may lead to food displacement for many animals. Urban birds are exposed to man-made objects that can result in variable food locations, unlike rural birds who inhabit areas where food locations are typically consistent. The introduction of unnatural obstacles may affect a sparrow's ability to find and reach food sources. Scientific studies have yet to find a significant increase in problem-solving skills related to foraging in urban versus rural birds. Our research seeks to determine the foraging efficiency of rural and urban house sparrows when exposed to obstructed food sources. Novel objects near a food source may scare birds away, but the necessity for food may overcome fear. House sparrows, Passer domesticus, are excellent model organisms to study urbanization effects because they inhabit both rural and urban environments. In our experiment, birds were habituated and trained to forage from a feeding grid. Using either natural or unnatural materials, we covered the entirety of a grid structure; food was placed in the same squares as when uncovered. Foraging efficiency was measured as the latency for a sparrow to uncover the food source and begin eating once released into the enclosure. We hypothesized that urban and rural house sparrows will differ in their foraging behavior. Therefore, we predicted that urban birds would exhibit higher foraging efficiencies when exposed to unnatural obstacles (e.g. plastic, snack wrappers) than rural birds. Regarding natural barriers (e.g. leaves, woodchips), we predicted that both urban and rural house sparrows will exhibit no behavioral differences. This study will provide insights into the foraging habits and, therefore, the survival of sparrows in an increasingly urbanized world. By identifying differences between rural and urban house sparrows' foraging strategies, the effects of urbanization on animal behaviors will be better understood.