Roosters don’t need to set an alarm to tell them when it’s time to crow — their internal circadian clock lets them anticipate sunrise with remarkable accuracy. To us sleepy humans, it may seem like they all start crowing at once. But scientists have found that roosters follow a strict social

Los vuelvepiedras rojizos ( Arenaria interpres) destacan sobre las aves playeras. Al emprender el vuelo, el vuelvepiedras despliega un vívido e inconfundible patrón de franjas oscuras y claras a lo largo de sus alas y cola. Y ese parloteo tan cómico es único en su tipo. A diferencia de la mayoría de

Hudsonian Godwits are tough birds to find, and they were once thought extinct due to overhunting. After nesting at sites scattered in the High Arctic, they migrate south on a route that takes them over the ocean from Canada to South America. In spring, they head north through the Great Plains

In August 2008, Kasatochi Island erupted in the middle of auklet breeding season, burying tens of thousands of chicks in hot ash. At first, the auklets’ future on the island appeared bleak. But in just a few years, the birds had returned in force. Thousands nested within the innumerable chambers

Beaks suited for opening tough, hard seeds — thick, conical beaks — evolved in more than one lineage of birds. Rose-breasted Grosbeaks are related to cardinals, which also have powerful beaks. Evening Grosbeaks belong to the finch family, which includes goldfinches and crossbills — an entire family

We make it a habit to detail the broad and beautiful spectrum of bird colors, but iridescent feathers are undoubtedly among the most mesmerizing. When sunlight hits the Bufflehead’s dark head feathers at the right angle, their colors transform into shades of the rainbow, from deep violet to green

Ross’s Geese and Snow Geese are both white-bodied waterfowl with black wingtips that can be difficult to tell apart. The pair are a great example of what science calls sister species, which occur when a portion of one species takes an evolutionary step away from the rest, resulting in a species

Found in the Sierra Madre, the Arizona Woodpecker has a special connection to the mountain range. Sharing mid-elevation pine and oaks with fellow border straddlers, these small brown birds with white and brown cheeks stand out from other Woodpeckers with their heavily marked white underparts

La forma en que algunas aves sacuden, agitan o despliegan la cola puede ser muy característica. Una cola que se sacude o se despliega con rapidez puede sugerirle a un depredador que el ave está especialmente alerta o que no será fácil de atrapar, y al mismo tiempo, puede advertir al resto de la

Swainson’s Hawks make an incredible journey every year, migrating 12,000 miles round-trip from North America’s prairies to Argentina’s pampas. What makes them truly unique is their diet. Most hawks hunt rodents and reptiles, but Swainson’s Hawks switch to insects, feasting on grasshoppers and