The American Robin (Turdus migratorius) is one of North America’s most recognizable songbirds and is classified as an opportunistic omnivore. This flexibility allows the species to thrive in diverse habitats, from woodlands to suburban lawns. A robin’s diet changes significantly based on the season and its stage of life, adapting to the availability of different food sources throughout the year. This adaptability is a major factor in the bird’s widespread distribution.
The Primary Diet of Ground-Foraging
The most iconic image of the robin is the robin’s stop-and-go foraging behavior on open lawns, searching for soft-bodied invertebrates. This protein-rich, ground-foraging diet is the primary food source during the spring and summer breeding season, sometimes making up 90% of the robin’s intake. Earthworms are a staple, often located by sight as the bird cocks its head to visually pinpoint the prey.
The robin consumes a wide array of insects and other small creatures. The protein and fat content from these animals is necessary for the energy demands of nesting and chick-rearing. Other soft-bodied prey includes:
- Beetle grubs
- Caterpillars
- Grasshoppers
- True bugs
- Flies
- Snails
- Spiders
- Millipedes and centipedes
Seasonal Shifts to Fruits and Berries
When the weather turns cooler and the ground freezes, robins transition away from their invertebrate-heavy diet because insects and worms become scarce. Beginning in late summer, and through the fall and winter, the diet shifts to plant-based foods for sustenance. This change provides energy and hydration when ground foraging is difficult.
Wild fruits and berries become the majority of their diet, sometimes accounting for 60% or more of their total intake. Robins show a preference for those in the rose family, such as wild cherries and plums. Specific winter-hardy fruits include holly, juniper, sumac, and the berries of dogwood and crabapple species. These fruits provide the carbohydrates and lipids needed to help the robins survive colder temperatures. The birds may also occasionally consume seed pulp, but they generally cannot digest larger, hard-shelled seeds.
The Specialized Diet of Nestlings
The dietary requirements of American Robin nestlings are specialized for rapid growth. For the first few days after hatching, parent birds deliver small, soft-bodied insects and earthworms. This diet is almost exclusively high-protein invertebrates, which fuel the astonishing growth rate of the young birds.
The parents, both male and female, will feed the nestlings up to a hundred times in a single day. They quickly move from giving partially digested food to delivering whole earthworms and large insects. The rich protein content enables the nestlings to reach the size of their parents and fledge the nest in as little as two weeks. Fruit is not a major part of the nestling diet, as high-protein animal matter is the priority for development.
Harmful Foods to Avoid
It is important to know which common human foods are inappropriate or harmful for robins. Foods with low nutritional value, such as bread, should be avoided, as they fill the bird’s stomach without providing necessary energy. Birds cannot properly digest milk, which can cause digestive distress and illness.
Large, hard bird seeds are difficult for robins to crack and can pose a choking hazard. Highly toxic substances for birds include caffeine (found in coffee or tea) and theobromine (found in chocolate). Safe alternatives for supplementary feeding include live or dried mealworms, which provide a protein boost. Small pieces of fresh, cut fruit like apples or berries can also be offered, but they should be raw and unsalted.