While birds are often seen pecking at lawns, grass is not a primary food source for most species. Their interaction with grass is nuanced, involving consumption of specific plant parts or foraging for other organisms within it. Different birds utilize grassy areas for distinct dietary needs, from direct plant consumption to hunting invertebrates.
Grass as a Dietary Component
Birds consume different parts of grass for various nutritional benefits, or they forage within grassy areas for other food sources.
Grass Seeds
Grass seeds are a common and valuable food source for many bird species. They are rich in nutrients like fats, carbohydrates, and proteins, providing an accessible, energy-dense meal, especially for smaller birds. Birds are drawn to areas with abundant grass seeds, viewing them as easy foraging grounds.
Grass Blades
Grass blades are occasionally eaten by some birds, though this is less common than seed consumption. While grass blades offer limited direct nutritional value, they can provide fiber, which aids in digestion. Some birds might also ingest small pieces of grit or dirt along with grass, which helps in grinding down harder foods in their gizzard. For certain species, consuming grass blades can also contribute to hydration.
Insects and Invertebrates
Birds frequently visit grassy areas to forage for insects and other invertebrates. Lawns contain grubs, worms, beetles, caterpillars, and spiders, which provide essential protein, particularly during breeding seasons for chick development. Freshly mowed lawns can make these insects more visible and accessible.
Common Grass-Eating Birds
Specific bird species exhibit distinct behaviors when interacting with grass as a food source, categorized by their primary method of consumption.
True Grazers
True grazers, like Canada Geese, directly consume grass blades. These birds are well-adapted to digesting plant material, and grass forms a significant part of their diet, especially in spring and summer. Canada Geese often prefer mowed lawns due to the unobstructed view they offer for spotting predators while feeding.
Seed-Eaters
Many bird species are primarily seed-eaters that frequent grassy areas. Sparrows, finches, doves, and pigeons commonly consume grass seeds. They are attracted to the abundance and accessibility of seeds on lawns, particularly newly sown ones.
Insect-Eaters
Other birds primarily forage for insects and invertebrates within the grass. American Robins are well-known for hunting earthworms and other insects on lawns. Robins prefer shorter grass for foraging, as it allows for easier movement and better visibility of prey. Starlings also frequently forage on lawns, probing the soil with their beaks to find grubs, beetles, and other invertebrates, which constitute a large portion of their diet. Their presence on a lawn can sometimes indicate an underlying insect problem, as they are effective at controlling pest populations.