Cardinals are a familiar sight with their bright red plumage and loud songs. As backyard birds, many people enjoy watching cardinals visit bird feeders and build nests. Understanding how cardinals reproduce and raise their young provides insight into their breeding biology.
When is cardinal breeding season?
The breeding season for cardinals occurs during the spring and summer months. In most parts of their range, cardinals start nesting activities in March and may continue through September. The exact timing varies by location and weather conditions each year.
Cardinals are opportunistic breeders. This means they can raise multiple broods in a single breeding season if conditions allow. The first brood is often completed by late April or May. After this, mature cardinals may go on to build a new nest and raise 2-3 broods total in a season.
The length of cardinal breeding season enables them to maximize reproductive success when food is abundant. It also gives cardinals more opportunities to re-nest if a nest fails early in the season due to predation or bad weather.
How do cardinals build nests?
Female cardinals take the lead in choosing nest sites and building the nests. They often construct nests 5-10 feet off the ground in thick vegetation. Common nest sites include dense shrubs, small trees, vines, and brushy areas.
Cardinals build a cup-shaped nest structure 3-4 inches across and 2-3 inches high. They weave the nest using grasses, twigs, bark strips, and other plant materials. The inner part of the nest is then lined with softer stuff like fine grass, pine needles, or animal hair.
Nest building takes 3-9 days to complete. The female cardinal does most of the construction, while the male may bring some material. The male stays nearby to guard the female while she builds the nest.
How many eggs do cardinals lay?
A clutch of cardinal eggs usually contains 3-4 eggs. The eggs are oval, about 1 inch long, and pale white or greenish-white with brown speckles.
The female lays one egg per day until the clutch is complete. She begins incubating the eggs after the second to last egg is laid. This helps synchronize hatching of the chicks.
In the case of second or third broods, the clutch size may be slightly smaller with 2-3 eggs. Larger clutches early in the season improve the chances some offspring will survive.
How long do cardinal eggs take to hatch?
Incubation lasts 11-13 days for cardinal eggs. The female cardinal incubates the eggs, only leaving the nest for short periods to eat and drink. She may be brought food by the male during this time.
Towards the end of incubation, the shells begin to fracture. The chicks use their egg tooth, a temporary projection on their beak, to start breaking out.
Hatching of the eggs is staggered over 12-48 hours. This results in chicks of varied sizes in the same brood. The older chicks are initially larger but the younger ones catch up quickly with sufficient food.
How are cardinal chicks fed?
Both parents share duties feeding the nestlings. They provide the chicks with regurgitated food consisting of insects, fruit, seeds, and other high protein items. Feeding happens frequently, sometimes over a dozen times per hour.
Cardinal chicks grow rapidly on this nutritious diet. Their eyes open by the third day. Pin feathers start emerging by day 5. And the chicks are fully feathered by 2 weeks old.
The nestlings are brooded by the female for warmth until about 5 days old. After this, she relies on the insulation of their growing feathers to help regulate their body temperature.
When do cardinal chicks leave the nest?
Cardinal chicks fledge from the nest about 9-11 days after hatching. At this stage, they can flutter short distances but still depend on their parents for another 2-3 weeks.
The fledglings follow their parents around begging to be fed as they learn to forage on their own. Male cardinals may take over much of the feeding duties at this stage to allow the female to start a new nest.
By 3-4 weeks out of the nest, the juvenile cardinals disperse to establish their own territories. Young females reach sexual maturity by the end of their first summer. Males take a bit longer to attain their full bright plumage and may not successfully breed until their second year.
Do cardinals mate for life?
Cardinals are socially monogamous and mate with the same partner each breeding season. Pairs remain together on their breeding territory year-round and often mate for multiple seasons.
However, cardinals are only genetically monogamous about 40% of the time. Extra-pair copulations are common, meaning the female may mate with a different male besides her social partner.
Even with these cases of infidelity, the male still contributes substantial parental care. About 70-90% of offspring are sired by the resident social mate according to DNA studies.
How many broods do cardinals raise per year?
Cardinals commonly raise 2-3 broods per breeding season. After fledging their first brood in April/May, the pair starts the process again for another brood.
Second and third broods follow the same timeline but are initiated 4-6 weeks after the previous nesting attempt. In warmer climates, cardinals may even fit in a very late nesting try.
Factors like food availability, habitat quality, and population density influence the number of broods possible. Raising multiple broods each season allows cardinals to replenish populations and offset any nest losses.
Do male and female cardinals build nests?
Female cardinals take the lead in nest site selection and construction. The male may contribute by bringing some nesting material, but the female does the majority of the actual building.
This division of labor is seen in most bird species. Females invest more energy into producing and laying eggs. So males compensate by assisting with nest construction and feeding duties.
The male cardinal’s role is to stand guard while the female builds. His bright coloration helps camouflage and conceal her from potential predators during her vulnerable nesting stage.
What materials do cardinals use to build nests?
Cardinals construct their nests using a variety of plant materials:
- Grass – Provides a framework for the nest structure
- Small twigs – Adds stability
- Tree bark – Used for binding the nest
- Vine tendrils – Helps weave the nest cup shape
- Pine needles – Offers a soft lining
- Animal hair – Insulates the eggs
Collecting suitable nesting materials requires some selective effort by the breeding pair. Cardinals often return to the same nesting territory, so may add onto an old nest from a prior year.
Where do cardinals build their nests?
Cardinals nest in trees and shrubs 5-10 feet above ground. Typical nest sites include:
- Dense evergreen shrubs
- Tangled vines
- Low branches of conifers
- Thorny vegetation like rose bushes
- Briar thickets
- Small saplings
Ideal nest sites offer concealment from predators and protection from the elements. Cardinals favor nesting in thick cover near edges, openings, or water sources where food is abundant.
Do cardinals use the same nest for multiple broods?
Cardinals typically build a new nest for each brood in a season rather than reusing the same one.
Old nests often degrade and collapse by the time the next brood starts. Also, parasites and pathogens accumulate over time, increasing the chance of disease transmission.
However, cardinals may repair and refresh an existing nest from earlier in the year to save time and energy. This is more likely for late summer nesting attempts when fewer materials are readily available.
How many broods of cardinals are there each year?
The number of broods a cardinal pair raises per breeding season depends on several factors:
- Food availability – Abundant food resources enable more frequent nesting
- Weather – Favorable spring and summer conditions extend breeding season
- Habitat quality – Better territories support larger broods
- Experience of the pair – Older birds tend to fledge more broods
In optimal conditions, cardinals may raise up to 3-4 broods. However, 2-3 is more common in most areas. First broods are larger, while late nests may only have 2-3 eggs.
Typical brood timeline:
| First brood | March – May |
| Second brood | May – July |
| Third brood | July – September |
Raising multiple broods each season allows cardinals to maintain high productivity even if some nests fail due to predators, weather, or other factors.
How often do cardinals lay eggs?
Cardinal pairs can raise multiple broods each breeding season. They typically lay eggs in a successive pattern:
- First nest: 3-4 eggs laid in March/April
- Second nest: 3 eggs laid 4-6 weeks after first brood fledges
- Third nest: 2-3 eggs laid 4-6 weeks after second brood fledges
The egg-laying intervals allow sufficient time for incubating, raising hatchlings, and re-nesting between broods. Larger clutches early in the season help ensure offspring success.
In warmer climates, cardinals may lay eggs nearly year-round. But most populations lack food supplies to support continuous breeding. Instead they maximize reproductive success within the spring/summer season.
How often do cardinal parents feed their young?
Cardinal parents deliver food to the nestlings very frequently to meet the high demands of their rapid growth. Some key facts about cardinal feeding habits:
- Both parents feed the chicks
- Nestlings can be fed over a dozen times per hour
- Feeding rate increases as the chicks grow
- Parents may remove fecal sacs to keep nest clean
- Chicks beg and jostle for position during feedings
The constant feedings provide a diet rich in insects, fruit pulp, seeds, and protein to fuel the nestling’s development. By 2 weeks old, the chicks are fully feathered and nearly equal the size of the adults.
What do baby cardinals eat?
The diet of nestling cardinals depends on the food sources available, but typically includes:
- Insects – Caterpillars, spiders, beetles, grasshoppers
- Fruit – Berries, pulpy fruits
- Seeds – Variety of wild seeds
- Protein – Eggs, tree sap
The adult cardinals deliver pre-digested food to the chicks by regurgitating it directly into their mouths. This soft, high calorie diet allows rapid growth.
As the nestlings near fledging age, the parents start bringing seeds and fruits intact to encourage the chicks to practice handling real food items.
How do baby cardinals learn to fly?
Cardinal chicks go through a staged process as they learn to fly and become independent:
- Leave the nest (fledge): Around 9-11 days old the chicks take short fluttering hops out of the nest, encouraged by the parents
- Strengthen flight: Over the next 2 weeks, the fledglings build flight skills by exercising their wings while still under parental care
- Forage skills: Parents teach fledglings to identify foods and feed on their own
- Independence: By 3-4 weeks after fledging the young are independent and disperse to their own territories
This gradual progression from nest to flying free allows cardinals to master the complex physical skills and behaviors required for survival.
What is a group of cardinals called?
Cardinals do not have special collective nouns like some other bird species. Some potential group names could be:
- A choir of cardinals
- A creation of cardinals
- A flash of cardinals
- A college of cardinals
These describe the traits cardinals exhibit when feeding or socializing in groups, such as their bright coloration, musical vocalizations, and associations with academic institutes whose sports teams use the cardinal mascot.
Why are male and female cardinals different colors?
Male and female cardinals show distinct plumage differences known as sexual dimorphism:
- Males – Vibrant red feathers across most of the body and face
- Females – Buff brown overall with reddish tinges on wings, tail, and crest
This divergence in appearance relates to their reproductive strategies and roles. The bright coloration of males advertises their fitness. Females are more camouflaged while incubating eggs.
The distinct plumage also aids cardinals in selecting proper mates of their own species and sex. Male red color even correlates to higher feeding rates and paternal care for offspring.
How long do cardinals live?
Cardinals have an average lifespan of 1-2 years in the wild. However, banded birds have been recaptured up to 15 years old. Some key factors influence longevity:
- Predators – Nestlings and fledglings have high mortality
- Harsh weather – Especially winter temperatures in northern climates
- Disease – Salmonellosis, avian pox, mites
- Abundant food and mild weather allow higher survival
In captivity, northern cardinals may live over 20 years with ideal conditions and care. But average lifespans are shorter for wild cardinals exposed to environmental pressures.
Conclusion
Understanding the breeding biology and reproductive strategies of cardinals provides insight into the natural history of these popular songbirds. Key highlights include:
- Cardinals breed during spring and summer, raising 2-3 broods per season
- Females build cup-shaped nests and lay clutches of 3-4 eggs
- Both parents incubate eggs and feed nestlings frequently
- Chicks fledge from the nest at 9-11 days old
- Pairs often mate for life, but extra-pair mating is common
- Bright male plumage and drab female appearance relate to reproductive roles
Cardinals exhibit adaptations enabling them to thrive across varied environments. Their vibrant colors and singing add splashes of life through the seasons for us to enjoy.
