Identity and characteristics of feathers used as lining in Tree Swallow (Tachycineta bicolor) nests in Indiana and Ohio

Nest building represents an important part of parental investment and can significantly impact reproductive success in many bird species. Tree Swallows (Tachycineta bicolor) are secondary cavity nesters that readily accept nest boxes and construct basic grass nest cups lined with molted feathers from other bird species. We identified and described the characteristics of the feathers used as nesting materials by Tree Swallows in 4 different habitats in Indiana and Ohio. We monitored 41 nest boxes in 2017 and 53 nest boxes in 2018. After chicks fledged, we collected feathers from nests, counted them, and characterized them by size, color, and type. Brown, medium length (5–10 cm), and contour feathers were significantly more common than other types of feathers. We compared the prevalence and characteristics of feathers in nests across different habitat types, with results showing that nests located near lakes had significantly more feathers than those in agricultural habitats. We identifie...