Habitat drivers of Barn Swallow (Hirundo rustica) feeding behaviour and breeding productivity

Barn Swallows Hirundo rustica belong to a declining guild of birds, and much remains unknown about the causes of these declines. Research in Europe has shown that pastures, hay fields, and livestock benefit Barn Swallow populations, and this study aimed to determine whether similar trends are found in a North American context. We studied this in two ways, first, by examining breeding productivity in three different habitats and then by examining how much they fed over certain types of fields. Breeding productivity parameters of swallows were largely similar although there were some differences, with higher fledging success in crop habitat and a higher proportion of intermediate nests in non-agricultural habitat in one of the years, however the overall picture suggests that non-agricultural, crop, and livestock are largely similar to one another, unlike what was found in European studies. Weather and manure management may have a greater impact on breeding productivity and warrant future research. We also found no difference in Barn Swallow feeding over grassland set-aside and cultivated fields, though the insect communities were different.