American Robins are associated with warm weather and earthworms. However, many do not migrate south for the winter, instead remaining in colder climates. These birds adapt their behavior and diet to survive the challenging winter months. Their winter food sources differ significantly from their spring and summer diets, which primarily consist of insects and worms.
Natural Winter Foods
During winter, when insects and earthworms become scarce or inaccessible due to frozen ground, American Robins primarily shift their diet to fruits and berries. This change is crucial as fruit provides the high calorie and sugar content necessary to fuel their metabolism and generate body heat in cold temperatures. Common natural berry sources include sumac, holly, juniper, viburnum, dogwood, and even the berries of poison ivy. These fruits often persist on shrubs, trees, and vines throughout the winter, providing a sustained food supply.
While fruit constitutes a large portion of their winter diet, robins still seek out protein when available. They may access dormant insects and insect larvae hidden under leaf litter or in sheltered areas. On warmer winter days, earthworms can sometimes become accessible in unfrozen ground, and robins will readily forage for these invertebrates. This opportunistic feeding helps them endure harsh conditions.
How Robins Forage for Winter Meals
Robins adapt their foraging strategies in winter. Unlike their familiar spring behavior of pulling earthworms from lawns, winter foraging often involves more arboreal activity. Robins form nomadic flocks, sometimes numbering in the hundreds or even thousands, and travel in search of abundant fruit-bearing trees and shrubs. These flocks will descend on a food source, consuming berries until the supply is depleted before moving to a new location.
Their sharp eyesight allows them to spot shriveled berries on bushes, and their beaks are suited for probing leaf litter for any accessible insects. While they are typically ground feeders, the scarcity of ground-level food in winter compels them to forage higher in vegetation. Their movements are dictated by food availability.
Providing Supplemental Winter Food
For individuals interested in assisting overwintering robins, offering supplemental food can provide a valuable energy boost. Robins do not typically eat birdseed, as their beaks are not designed for cracking seeds and their digestive systems are not suited for them. Instead, high-protein options like live or dried mealworms are particularly beneficial, serving as a substitute for their preferred insect diet. Soaking dried mealworms in water can also provide valuable moisture.
Chopped fruits are also readily accepted, including apple slices, raisins, cranberries, blueberries, strawberries, and cherries. Suet, especially varieties mixed with fruit or bugs, can offer high-calorie fat for energy. These foods should be placed on flat platforms, large trays, or directly on the ground, as robins are natural ground feeders and often do not visit traditional hanging feeders. Maintaining clean feeding stations is important to prevent the spread of disease, with feeders needing cleaning every two weeks using a diluted bleach solution. Providing fresh, unfrozen water is also beneficial, as birds need hydration even in cold weather.