Even in winter, some birds — including Black-capped Chickadees, House Finches, and American Robins — greet the sunrise with song. We normally hear the dawn chorus in springtime, when birds sing to define territory and attract mates. But birds don’t breed by warmth alone. Day length is a far more reliable spark than weather. We know that photo-receptors in birds’ brains sense the increasing light. It triggers the production of hormones, which helps bring on the breeding season. Our early birds aren’t breeding in February. But they’re warming up. Learn more at BirdNote.org.

Black Rails are marsh-inhabiting birds, more often heard than seen. Many Black Rails nest in marshes along the Atlantic seaboard and in the Midwest. But in winter they concentrate in the coastal marshes of East Texas, Louisiana, and Florida, areas that face many threats. US populations of Black Rails have declined greatly. In recent decades, the enactment of laws protecting wetlands has improved the bird's prospects. Still, the Black Rail remains on American Bird Conservancy's "red list." Learn more at BirdNote.org.

When Chidi Paige moved from Nigeria to the U.S., she began running a youth STEM program and had to teach lessons on bird identification. She was in for a challenge: she had to learn the local bird species quickly. On a birding trip, she spotted a Yellow Warbler in a pine tree. The beautiful warbler got Chidi hooked on birding. She has designed several games to make learning bird identification fun for kids. Learn more at BirdNote.org.

In the 1990s, train engineers in Japan built trains able to travel nearly 170 miles per hour. The problem was that when the trains exited a tunnel, the air in front of their bullet-shaped noses expanded rapidly, creating a loud “tunnel boom.” The chief engineer, a birder, looked to the shape of a kingfisher’s bill to design long, narrow train noses that parted the air. The trains became both quieter and more efficient. Learn more at BirdNote.org.

Flapping with deep, slow wing-motion, a Short-eared Owl appears almost to float above the ground. This owl has an extensive world range, including North and South America, Europe, and Asia. Still, it's declining, due to development, agriculture, and overgrazing. American Bird Conservancy and Partners in Flight consider this bird at-risk. But the federal Conservation and Wetland Reserve Programs are showing promise for Short-eared Owls, by preserving large blocks of habitat. Let your elected representatives know that you support these programs! Learn more at BirdNote.org.

On a winter morning in Costa Rica, a colorful choir welcomes the day. A pair of Bay Wrens sings a brisk duet just before sunrise. Perched in the upper canopy of the tropical lowland forest, a group of Keel-billed Toucans calls out. In a nearby tree, Purple-throated Fruitcrows (like this one) add their voices to the chorus. Then a male Montezuma Oropendola belts out an electrifying series of notes — one of the most distinctive voices in the tropics. Finally, a Bright-rumped Attila calls from its perch. Learn more at BirdNote.org.

This show pairs birds that make sounds on opposite extremes: the highest-pitched bird, the Black Jacobin hummingbird, duets with the Southern Cassowary, one of the lowest-pitched birds. The faint, buzzy song of the Grasshopper Sparrow joins the voice of the White Bellbird, the loudest bird in the world.

This show was produced by World According to Sound. BirdNote and World According to Sound are teaming up for an immersive, 70-minute, virtual event about the sounds of birds. Learn more at BirdNote.org.

A tube of black oil sunflower seeds isn’t “natural”…and neither is a suet cake. Yet as soon as you hang them up, the neighborhood birds, like these female finches, find them. Those grosbeaks at your feeder probably never ate sunflower seeds in nature. Sunflowers grow in open plains, while grosbeaks live in forests. But birds have a substantial capacity to learn, either by action or by witnessing other birds at a feeder. Learn more at BirdNote.org.

A typical bird nest will have maybe four to six eggs neatly arranged by the parent to hunker down on. But in one Rhea nest, you may find between 50 and 80 eggs! And they’re not all from the same set of parents. Male Rheas mate with several females and then build a single nest on the ground to hold all the eggs from each of them. Learn more at BirdNote.org.

Rosemary Mosco was drawn to birds as a shy child, because they rewarded patience. In college, she struggled to connect with her classes in anthropology. She began volunteering with a group in Toronto that tries to stop birds from hitting windows. At the same time, she created a cartoon about a lonely bird that befriends the moon and flies around the city having adventures. She now combines art and science as a cartoonist and science writer. Learn more at BirdNote.org.