Indigo Bunting: Birdwatching Guide & Facts

With their striking blue plumage, male Indigo Buntings are a summer favorite amongst birders. They delight the air with their songs, sitting proudly on their perches. Whether you spot an Indigo Bunting on the roadside, out in the field, or your backyard, it is always a memorable experience. 

In this birdwatching guide, you’ll learn where Indigo buntings are, how to identify them, and tips for attracting them to your backyard. We’ll also explore what makes them so unique, other than their lovely blue feathers, of course.

Indigo Bunting Identification

Indigo buntings (Passerina cyanea) are small, sparrow-sized birds in the Cardinalidae or Cardinal family. Like other cardinal family members, they have a short tail and a conical bill. 

The male Indigo Bunting is easy to identify during breeding season with his dark blue plumage from head to tail. The head has slightly darker blue feathers than the rest of the body. The wings are black and blue.

The non-breeding male is less noticeable and takes on more brown plumage on his head, back, and belly. While molting, he can have patchy areas of brown and blue. 

The immature male and female are less conspicuous, with dark brown feathers above and pale tan below. They have faint sparrow-like streaks on the chest. Females stay more camouflaged to help protect their young, which they predominantly rear.  

What do Indigo Buntings Sound Like?

One of the easiest ways to spot an Indigo Bunting is by listening for their song in their preferred habitat. The males like to perch on top of tall grass or shrubs and loudly sing their rapid and excited song. Once you hear it, you’ll soon spot the little bird nearby, perched on a branch above the shrubby undergrowth where the female hides. 

I recommend listening closely to their song on Audubon to familiarize yourself with its pattern and pitch. That way, when you hear it out in the field, you’ll quickly recognize and locate the Indigo Bunting. 

Range and Habitat

In the spring, Indigo Buntings migrate across the Gulf of Mexico and the Great Plains states to breed throughout the Central and Eastern United States. Their range extends from Eastern North Dakota down to Eastern Texas all the way over to the East Coast. The Indigo Bunting is also found in parts of the Southwest, from Southern Colorado over to Southern California. 

The Indigo Bunting is abundant and widespread, making them easy to find if you know where to look. For breeding and nesting, they prefer brushy and weedy edges, such as roadside, fields, and forest edges. 

You can find them in orchards, meadows bordering a forest, railroad or powerline clearings within a forest, swamp and wetland edges, and woodland clearings. In their western range, they are most often found near streams. 

During migration, they travel in flocks, foraging in open lawns, grasslands, and fields. They migrate to their non-breeding grounds from September to mid-November. 

Indigo Buntings winter in southern Florida, southern Mexico, Central America, the Caribbean Islands, and northern South America. In these areas, they prefer brushy habitats, such as forest undergrowth, weedy fields, and woodland edges.

How to Attract an Indigo Bunting to Your Backyard 

The best way to attract Indigo Buntings to your backyard is to provide (or maintain) their preferred habitat. This means leaving an area of weeds and shrubs to nest in. 

They especially love thistles, tall grass seeds, and insects. In the summer, their diet consists mostly of spiders, beetles, and caterpillars. As such, it’s important to not use pesticides in your yard to ensure they have plenty of insects to eat (which will help the other birds visiting your backyard too).  

You can attract the Indigo Bunting with a bird feeder, but they won’t stick around unless you have shrubby undergrowth. Otherwise, they may enjoy your mealworms and sunflower and nyjer seeds while passing through during their spring and fall migration.

Interesting Facts About the Indigo Bunting 

The male Indigo Bunting is well known for his beautiful blue plumage, but this isn’t the only unique feature these birds have. These birds migrate at night, guided by the stars. And, in fact, their feathers aren’t really blue…

Star Navigation 

In 1967, a research study showed that Indigo Buntings depend on constellations to orient them as they migrate at night. As migration season approaches, they become more active at night. When they migrate, these birds are highly active from dusk to just before sunrise, using the stars to navigate through the dark. 

While it’s still not fully understood how Indigo Buntings or other night-time migrators use the stars for guidance, it’s thought that they start learning as early as nestlings. It’s proposed that they start studying the night sky before they can fly, and they instinctively know the direction to head when the season starts to shift. 

According to Cornell Lab All About Birds, “The birds [Indigo Buntings] possess an internal clock that enables them to continually adjust their angle of orientation to a star—even as that star moves through the night sky.” 

Plumage Color 

Surprisingly, the male Indigo Bunting isn’t actually blue. Their feathers don’t have blue pigment. Rather, their feathers appear dark blue due to microscopic structures that refract and reflect blue light. This interesting fact isn’t excluded to Indigo Buntings; all blue birds lack blue pigment. 

While their feathers don’t have any blue pigment, they still have the pigment melanin. This pigment has a brown-black hue, which is easily apparent in non-breeding males and females. 

You can even see this pigment in one of the male Indigo Bunting’s “blue” feathers. If you hold up the feather towards the light, the brown-black hues are illuminated. This is because the light is behind the feather; when the light hits the feather from the front, it appears blue. 

The Beautiful and Fascinating Indigo Bunting 

Whether you’re a seasoned birder or a novice, the Indigo Bunting is a prize to see. No matter how many years you witness them breed or pass through, they always invoke a sense of awe, especially when their blue feathers shine in the bright summer light. 

Now that you’ve learned how to identify the Indigo Bunting and know where to find them, it’s only a matter of time before you spot one out in the field. Remember to listen to their excited warbling song. Once you spot one, you can impress your fellow birdwatchers with your knowledge about this bird, such as their star navigation and “blue” feathers. 

Hopefully, on your next springtime birdwatching adventure, you’ll see the beautiful and fascinating Indigo Bunting. In the meantime, check out our other blogs, such as The 8 Species of Buntings in North America or The Splendid Steller’s Jay.