Northern cardinals are a common presence in North American backyards, known for their striking appearance. The male cardinal boasts vibrant red plumage, while the female displays a more subdued reddish-brown coloration with hints of red. These birds are widespread across the continent. This article explores the timing of when their young are born and how they develop.
Cardinal Breeding Season
Northern cardinals begin breeding in early spring, often in March or April. Warmer temperatures and increasing daylight hours serve as environmental cues that trigger this season. The breeding period can extend well into the summer, sometimes lasting through September. A primary indicator that the breeding season is underway is the male cardinal’s distinctive song, which he uses to defend his territory and attract a mate. Courtship feeding, where the male offers food to the female, is another early sign of pair formation.
From Egg to Fledgling
Nest building is primarily undertaken by the female cardinal, though the male may assist by bringing materials. Nests are cup-shaped and constructed in dense shrubs, small trees, or vine tangles, usually positioned between 3 to 10 feet off the ground. These structures are woven from twigs, grass, bark strips, leaves, and rootlets, taking 3 to 9 days to complete. Cardinals do not reuse their nests for subsequent broods.
Once the nest is ready, the female lays a clutch of two to five eggs, with three to four eggs being common. She lays one egg per day. These eggs are grayish-white, buffy white, or greenish-white, marked with brown, gray, or purplish speckles. The incubation period lasts 11 to 13 days, with the female performing most of the incubation. The male often brings food to the incubating female.
Upon hatching, baby cardinals are altricial, meaning they are born blind, naked, and helpless, with only sparse grayish down feathers. They develop rapidly. The nestling period, during which the young remain in the nest, spans 7 to 13 days, with 9 to 11 days being a common timeframe. Both parents feed the nestlings, primarily providing them with insects.
Fledging occurs when young cardinals leave the nest, 9 to 11 days after hatching. Fledglings are still mostly covered in brown-gray feathers and lack the vibrant red of adult males. Their crest, a distinguishing feature, begins to develop around 10 days after hatching. Even after leaving the nest, fledglings remain dependent on their parents for several weeks, for 25 to 56 days, for continued feeding and protection. The male cardinal may take on the primary role of feeding the fledglings, allowing the female to begin preparations for another nesting attempt.
Multiple Broods
Northern cardinals are prolific breeders, raising multiple broods within a single breeding season. A pair commonly has two to three broods per year, and occasionally even four. Short incubation and nestling periods contribute to raising successive broods. If a first brood is successful, the female may initiate a new nest soon after, while the male continues to care for the recently fledged young. This reproductive strategy allows young cardinals to be observed throughout the spring and summer months.