Unlike many other birds, northern cardinals are permanent residents in their range, staying put even through cold winters. You can spot these bright red birds throughout the year in much of North America, especially in the eastern United States and parts of Canada. But why don’t cardinals migrate? Their behavior is a fascinating blend of biology, adaptability, and evolutionary strategy.
Cardinals Are Well-Adapted to Winter
One reason cardinals don’t need to migrate is that they are well-suited to withstand colder climates. Their dense feathers provide insulation against winter temperatures, helping them conserve body heat. Cardinals are also larger than many migratory songbirds, and this extra body mass helps them retain warmth. This natural adaptation allows them to stay comfortable and active even in snowy conditions.
Access to Year-Round Food Sources
Cardinals primarily eat seeds, berries, and fruit, which are more readily available year-round compared to other food sources like insects. While food availability can decrease in winter, cardinals can still find enough seeds and berries in their habitats to sustain themselves. They also take advantage of backyard bird feeders, which provide an additional, reliable source of food during the colder months.
Cardinals have even adapted their feeding habits to winter, fluffing up their feathers and conserving energy by feeding during the warmest parts of the day when food sources are more accessible.
Territorial Behavior and Strong Site Fidelity
Cardinals are highly territorial birds, especially during the breeding season. Both males and females are known to defend their established territories fiercely, chasing away intruders to maintain control of their space. This strong attachment to a specific area, known as site fidelity, reduces their motivation to migrate because they have already invested time and energy in claiming and defending their territory.
Males in particular often stay in one area to ensure a steady territory for mating, which further reinforces their tendency to remain year-round residents. This behavior benefits cardinals by giving them an established territory for breeding come spring.
Evolutionary Strategy: Saving Energy by Staying Put
Migration is a physically demanding and risky activity. Birds that migrate face numerous dangers, including exhaustion, predation, and unpredictable weather. By staying put, cardinals conserve energy, avoid the hazards of migration, and maintain access to familiar food sources and shelter. This evolutionary strategy has paid off, as cardinals have become widespread and successful, expanding their range over time.
Cardinals Rely on Dense Vegetation for Winter Shelter
Cardinals are non-migratory in part because they use dense vegetation for shelter. They roost in evergreen trees and thick shrubs, which provide warmth, camouflage, and wind protection during winter. These shelters offer cardinals a safe place to rest, which is crucial for surviving cold nights and extreme weather.
The Expansion of Cardinals’ Range
Interestingly, cardinals’ range has actually expanded northward in recent decades, partly due to climate change and the increase in backyard bird feeders, which provide a reliable winter food source. This expansion reflects their adaptability and ability to thrive in colder climates, reinforcing their status as a non-migratory bird.
A Resilient, Year-Round Presence
In summary, cardinals stay put because they’re physically adapted to colder weather, have a steady food supply, and benefit from defending a familiar territory. Their resilience and resourcefulness allow them to endure winter and thrive without needing to migrate. As a result, they bring beauty and color to landscapes throughout the year, making them a beloved presence in gardens and winter scenes.
By not migrating, cardinals demonstrate the adaptability that makes them such a successful and beloved bird species.