Quick Answer
Yes, cardinals can and do breed in August. The breeding season for cardinals typically runs from March through September, with most nesting activity happening between May and August. As summer winds down in August, some late nestings may occur, especially for younger birds that are breeding for the first time that year. Cardinals are prolific breeders and can raise multiple broods in a single breeding season.
Overview of Cardinal Breeding
The northern cardinal (Cardinalis cardinalis) is a year-round resident across much of eastern North America. Its breeding range extends from southern Canada down through the eastern and central United States to the Gulf Coast. Cardinals are non-migratory, remaining on their breeding grounds throughout the year.
Cardinals reach sexual maturity and begin breeding at around one year of age. The male cardinal uses its brilliant red plumage and songs to attract a mate. Once paired, the breeding couple remains monogamous and may mate for life, often raising multiple broods together over several breeding seasons.
The cardinal’s breeding season typically runs from March through September, though exact timing varies across their range. In southern areas, cardinals may start nesting as early as late February, while northern cardinals usually begin nesting in April or May. Most nesting activity peaks between May and August.
Why Cardinals Breed in August
There are a few key reasons why cardinals continue breeding into August:
– Extended breeding season – Cardinals can raise multiple broods in a single season. After successfully fledging one or more broods earlier in summer, adults may build new nests and breed again in August.
– Late nesters – Younger birds breeding for the first time often nest later in the season. These novice breeders may just be getting started with their first brood in August.
– Re-nesting attempts – Cardinals will re-nest after a failed breeding attempt. Loss of eggs or young prompts the parents to try again, potentially extending nesting into August.
– Sufficient food supplies – Late summer insect abundance and ample seed and berry crops allow cardinals to continue breeding. As long as food remains available, they can provision more broods.
– Mild summer weather – If temperatures remain comfortable and rain is adequate, cardinals may take advantage of benign conditions to raise additional broods.
Cardinal Nesting Biology
When breeding in August, cardinals go through the same nesting process as earlier in summer:
– Nest building – The female cardinal builds a new cup-shaped nest out of twigs, bark strips, vines, and grasses. It is constructed in a shrub, small tree, or dense tangle of vegetation.
– Egg laying – Once the nest is complete, the female lays 1-4 pale bluish or greenish eggs, sometimes speckled with brown. The eggs are laid one per day.
– Incubation – The female incubates the eggs for 11-13 days before they hatch. The male may occasionally relieve her. Incubation during hot August weather helps regulate egg temperature.
– Nestlings – Both parents feed the naked, helpless nestlings regurgitated insects and seeds. Nestlings fledge at 9-11 days old.
– Fledglings – The fledged young remain dependent on the care of both parents for 2-3 weeks. The adults continue bringing them food as they learn to forage.
How Cardinals Care for Late Broods
Raising young in August takes extra effort on the part of cardinal parents. They use various strategies to help late broods thrive:
– Finding nutrient-rich foods – Cardinals seek out energy-dense seeds and fat-rich insects to provision growing nestlings. Popular foods include sunflower seeds, berries, beetles, cicadas, and caterpillars.
– Feeding fledglings – Adults aggressively defend foraging territories and maintain reliable food sources to satisfy the appetites of their recently fledged young.
– Keeping nests cool – On hot days, incubating or brooding females may leave the nest for longer periods. Males brings food and stand guard over nests in the female’s absence.
– Nest placement – Nest sites with shade or cooling breezes help prevent overheating. Nest heights tend to increase later in summer to access cooler microclimates.
– Adjusting routines – Adults may shift their activity patterns on scorching afternoons, foraging more actively at dawn, dusk, or overnight when temperatures are cooler.
Challenges for Late Broods
Breeding in August can be risky for cardinals. Some challenges they may face include:
– Hot temperatures – Excessive heat takes a toll on eggs, nestlings, and even adult cardinals. Cool microhabitats help reduce overheating risk.
– Dwindling food supplies – As summer wanes, preferred foods like berries and caterpillars become less abundant. Adults work harder to find sufficient nutrition.
– Hungry predators – With juvenile predators on the prowl and migrant raptors passing through, nests suffer heavy losses in late summer. Watchful parents provide the best defense.
– Lack of experience – Younger birds breeding for the first time make mistakes and lose nests at higher rates. With experience, their breeding success improves.
– Shortened season – Late nests have a tighter timeline to fledge before cold weather returns. Nestlings may not fully develop if parents can’t adequately provision them.
Typical Timeline for August Cardinal Breeding
Here is an approximate timeline for the cardinal breeding process during August:
Early August | Nest building begins |
Mid-August | Eggs laid (incubation lasts 11-13 days) |
Late August | Nestlings hatch and are fed by parents (fledging at 9-11 days) |
End of August | Fledglings leave nest but still dependent on parental care |
This schedule allows fledglings to become independent before cold temperatures arrive in autumn. However, the timeline may vary based on geography, weather, and other factors.
Signs Cardinals Are Breeding in August
Here are some clues that cardinals in your area may be breeding in August:
– Adults carrying nesting material like twigs, bark, and grasses, often disappearing into dense vegetation
– Female cardinals making frequent trips to and from a nest, especially if carrying food
– Males perched near nests, singing and chasing away intruders
– Aggressive behavior and territorial disputes between males
– Distressed alarm calls from adults signaling predators near a nest
– Young begging calls coming from a nest, indicating nestlings are present
– Recently fledged juveniles following adults and begging noisily for food
– Adults actively provisioning fledglings for several weeks after young leave the nest
– Males continuing to court females with song and displays, or multiple females visiting a single male
Supporting Late-Summer Cardinal Nesting
You can help encourage cardinals that are breeding in your area during August by:
– Providing a source of fresh water for drinking and bathing
– Landscaping with dense native shrubs and small trees that offer nesting sites
– Avoiding pruning or removal of potential nesting habitat during nesting season
– Letting some areas of the yard grow more natural with tall grasses and vegetation
– Supplying bird feeders with nutritious foods like sunflower seeds, suet, and mealworms
– Minimizing the use of pesticides that reduce insect prey for nestlings
– Keeping pet cats indoors to protect nests from predation
– Installing nest boxes suited for cardinals in optimal habitat
– Reporting any color-banded cardinals seen to researchers monitoring local populations
Frequently Asked Questions
Why do cardinals have such a long breeding season?
Cardinals are able to extend their breeding season over many months because they inhabit relatively mild climates year-round. This allows them to take advantage of abundant food supplies through the summer to raise multiple broods. Their sturdy nests and willingness to re-nest also promotes longer breeding.
Do both male and female cardinals build the nest?
No, only the female cardinal builds the nest. However, the male may accompany her and stand guard as she gathers materials. The male’s bright coloration could attract predators, so keeping watch allows her to nest-build with fewer disruptions.
How do the adults keep late nests cool in summer?
Cardinals use nest placement and construction to help regulate temperature. They may situate nests in cooler microclimates with more shade or airflow. On hot days, adults stand guard over nests so the brooding female can take longer breaks to cool off. The outer nest shell provides insulation while allowing air to flow through the inner cup.
Why don’t young cardinals breed their first summer?
Young cardinals don’t reach full adult plumage and sexual maturity until after their first winter. They use this time to learn critical skills like foraging and avoiding predators. Waiting until the following spring ensures young birds have the abilities and energy reserves needed for successful breeding.
How can I offer extra support for late cardinal nests?
Providing a reliable source of water helps cardinals keep nestlings hydrated and cool. Suet, mealworms, and seed blends offer nutritious foods for overworked adults provisioning demanding fledglings. Leaving unmown areas with dense cover gives hiding fledglings safe foraging spots. Turning off outdoor lights at night reduces disorientation. Avoid pruning near active nests.
Conclusion
August represents the winding down of the breeding season for many cardinal pairs, but it can also be a busy period for younger birds and re-nesting adults. Sustained food availability, amenable weather, quality nesting sites, and attenuated care from the parents are keys to success when undertaking the huge energy demands of late summer nesting. Supportive conditions allow cardinals to take advantage of this final opportunity to raise one more brood before autumn arrives. With good planning, these late-season cardinal families can thrive.