American robins, with their familiar presence and distinctive song, are a common sight. Each spring, their nesting period begins, a display of natural dedication as they prepare to raise new generations. Observing their behaviors offers a glimpse into the coordinated efforts of avian reproduction, from nest construction to nurturing their young.
The Female’s Primary Role
The female American robin undertakes the primary responsibility for building the nest and incubating the eggs. She constructs a cup-shaped nest from twigs and grasses, reinforcing it with mud and lining the interior with fine, dry grass. This process can take two to six days. Once ready, she lays three to five distinctive pale blue eggs, usually one per day.
Incubation, the process of keeping the eggs warm for development, is primarily performed by the female. She sits on the eggs for approximately 12 to 14 days, rarely leaving the nest for more than 5 to 10 minutes at a time. To maintain the optimal temperature, she utilizes a specialized brood patch, a featherless area on her belly that allows direct transfer of her body heat to the eggs. She also rotates the eggs several times daily with her bill, ensuring uniform temperature.
The Male’s Contributions
While the female robin incubates the eggs, the male robin plays a supportive role during this period. Male robins do not sit on the eggs, as they lack the specialized brood patch for incubation. Instead, his contributions focus on ensuring the safety of the nesting site and his mate.
The male defends their territory from other robins and potential predators, often using his loud songs as a territorial display. He remains close to the nest, responding quickly to alarm calls from the female. The male may also bring food to the incubating female, allowing her to remain on the nest.
Shared Parental Duties
Once robin eggs hatch, 12 to 14 days after incubation, parental duties shift to a shared effort. The naked, blind, and reddish hatchlings require constant feeding, and both parents work to provide nourishment. They forage for a protein-rich diet of insects and earthworms, making frequent trips to the nest, sometimes as many as 100 to 150 feeding visits per day.
Beyond feeding, both parents contribute to nest hygiene by removing fecal sacs, which keeps the nest clean. The female continues to brood the young, providing warmth and protection. Young robins remain in the nest for 9 to 16 days after hatching before they fledge, or leave the nest. After fledging, the young birds remain close to their parents for a few days to two weeks, receiving food and guidance. The male will take over care of the fledglings while the female prepares for a second brood.