What do birds eat? A trophic and taxonomic analysis of breeding bird diets in North America based on literature citations

Bird populations are declining throughout North America, especially among Neotropical migrants and grassland birds.  Poor habitat quality is one cause of such declines. Because 96% of all terrestrial bird species rear young on insects, we can restore breeding habitats by planting the plants that produce the insects birds prefer. Here I report data on breeding bird diets from an in-depth literature review of past studies of breeding bird diets. I also compare the quality of these data to data generated from images of birds carrying insects to the nest.